Creates an system management API to allow complex configurations and features to be programmed into a CoreSight infrastructure.

A feature is defined as a programming set for a device or class of devices.

A configuration is a set of features across the system that are enabled for a trace session.

The API will manage system wide configuration, and allow complex programmed features to be added to individual device instances, and provide for system wide configuration selection on trace capture operations.

This patch creates the initial data object and the initial API for loading configurations and features.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- drivers/hwtracing/coresight/Makefile | 2 +- .../hwtracing/coresight/coresight-config.h | 142 +++++++++++++ drivers/hwtracing/coresight/coresight-core.c | 12 +- .../hwtracing/coresight/coresight-etm-perf.c | 2 +- .../hwtracing/coresight/coresight-etm-perf.h | 2 +- .../hwtracing/coresight/coresight-syscfg.c | 199 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 46 ++++ 7 files changed, 401 insertions(+), 4 deletions(-) create mode 100644 drivers/hwtracing/coresight/coresight-config.h create mode 100644 drivers/hwtracing/coresight/coresight-syscfg.c create mode 100644 drivers/hwtracing/coresight/coresight-syscfg.h

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index d60816509755..3d037f17aade 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -4,7 +4,7 @@ # obj-$(CONFIG_CORESIGHT) += coresight.o coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \ - coresight-sysfs.o + coresight-sysfs.o coresight-syscfg.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \ coresight-tmc-etr.o diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h new file mode 100644 index 000000000000..21aa7464dcdc --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -0,0 +1,142 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2020 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#ifndef _CORESIGHT_CORESIGHT_CONFIG_H +#define _CORESIGHT_CORESIGHT_CONFIG_H + +#include <linux/coresight.h> +#include <linux/types.h> + +/* CoreSight Configuration Management - component and system wide configuration */ + +/* + * Register type flags for register value descriptor: + * describe how the value is interpreted, and handled. + */ +#define CS_CFG_REG_TYPE_STD 0x80 /* reg is standard reg */ +#define CS_CFG_REG_TYPE_RESOURCE 0x40 /* reg is a resource */ +#define CS_CFG_REG_TYPE_VAL_PARAM 0x08 /* reg value uses param */ +#define CS_CFG_REG_TYPE_VAL_MASK 0x04 /* reg value bit masked */ +#define CS_CFG_REG_TYPE_VAL_64BIT 0x02 /* reg value 64 bit */ +#define CS_CFG_REG_TYPE_VAL_SAVE 0x01 /* reg value save on disable */ + +/* + * flags defining what device class a feature will match to when processing a + * system configuration - used by config data and devices. + */ +#define CS_CFG_MATCH_CLASS_SRC_ALL 0x0001 /* match any source */ +#define CS_CFG_MATCH_CLASS_SRC_ETM4 0x0002 /* match any ETMv4 device */ + +/* flags defining device instance matching - used in config match desc data. */ +#define CS_CFG_MATCH_INST_ANY 0x80000000 /* any instance of a class */ + +/* + * Limit number of presets in a configuration + * This is related to the number of bits (4) we use to select the preset on + * the perf command line. Preset 0 is always none selected. + * See PMU_FORMAT_ATTR(preset, "config:0-3") in coresight-etm-perf.c + */ +#define CS_CFG_CONFIG_PRESET_MAX 15 + +/** + * Parameter descriptor for a device feature. + * + * @name: Name of parameter. + * @value: Initial or default value. + */ +struct cscfg_parameter_desc { + const char *name; + u64 value; +}; + +/** + * Representation of register value and a descriptor of register usage. + * + * Used as a descriptor in the feature descriptors. + * Used as a value in when in a feature loading into a csdev. + * + * Supports full 64 bit register value, or 32 bit value with optional mask + * value. + * + * @type: define register usage and interpretation. + * @offset: the address offset for register in the hardware device (per device specification). + * @hw_info: optional hardware device type specific information. (ETM / CTI specific etc) + * @val64: 64 bit value. + * @val32: 32 bit value. + * @mask32: 32 bit mask when using 32 bit value to access device register - if mask type. + * @param_idx: parameter index value into parameter array if param type. + */ +struct cscfg_regval_desc { + struct { + u32 type:8; + u32 offset:12; + u32 hw_info:12; + }; + union { + u64 val64; + struct { + u32 val32; + u32 mask32; + }; + u32 param_idx; + }; +}; + +/** + * Device feature descriptor - combination of registers and parameters to + * program a device to implement a specific complex function. + * + * @name: feature name. + * @description: brief description of the feature. + * @item: List entry. + * @match_flags: matching information if loading into a device + * @nr_params: number of parameters used. + * @params_desc: array of parameters used. + * @nr_regs: number of registers used. + * @regs_desc: array of registers used. + */ +struct cscfg_feature_desc { + const char *name; + const char *description; + struct list_head item; + u32 match_flags; + int nr_params; + struct cscfg_parameter_desc *params_desc; + int nr_regs; + struct cscfg_regval_desc *regs_desc; +}; + +/** + * Configuration descriptor - describes selectable system configuration. + * + * A configuration describes device features in use, and may provide preset + * values for the parameters in those features. + * + * A single set of presets is the sum of the parameters declared by + * all the features in use - this value is @nr_total_params. + * + * @name: name of the configuration - used for selection. + * @description: description of the purpose of the configuration. + * @item: list entry. + * @nr_feat_refs: Number of features used in this configuration. + * @feat_ref_names: references to features used in this configuration. + * @nr_presets: Number of sets of presets supplied by this configuration. + * @nr_total_params: Sum of all parameters declared by used features + * @presets: Array of preset values. + * + */ +struct cscfg_config_desc { + const char *name; + const char *description; + struct list_head item; + int nr_feat_refs; + const char **feat_ref_names; + int nr_presets; + int nr_total_params; + const u64 *presets; /* nr_presets * nr_total_params */ +}; + +#endif /* _CORESIGHT_CORESIGHT_CONFIG_H */ diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index ca75b0b54e1f..868785983c79 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -21,6 +21,7 @@

#include "coresight-etm-perf.h" #include "coresight-priv.h" +#include "coresight-syscfg.h"

static DEFINE_MUTEX(coresight_mutex); static DEFINE_PER_CPU(struct coresight_device *, csdev_sink); @@ -1764,13 +1765,22 @@ static int __init coresight_init(void)

ret = etm_perf_init(); if (ret) - bus_unregister(&coresight_bustype); + goto exit_bus_unregister;

+ /* initialise the coresight syscfg API */ + ret = cscfg_init(); + if (!ret) + return 0; + + etm_perf_exit(); +exit_bus_unregister: + bus_unregister(&coresight_bustype); return ret; }

static void __exit coresight_exit(void) { + cscfg_exit(); etm_perf_exit(); bus_unregister(&coresight_bustype); } diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index f123c26b9f54..15310c72f89f 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -748,7 +748,7 @@ int __init etm_perf_init(void) return ret; }

-void __exit etm_perf_exit(void) +void etm_perf_exit(void) { perf_pmu_unregister(&etm_pmu); } diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h index 3e4f2ad5e193..29d90dfeba31 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.h +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h @@ -83,6 +83,6 @@ static inline void *etm_perf_sink_config(struct perf_output_handle *handle) #endif /* CONFIG_CORESIGHT */

int __init etm_perf_init(void); -void __exit etm_perf_exit(void); +void etm_perf_exit(void);

#endif diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c new file mode 100644 index 000000000000..417db3f92c2f --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include <linux/platform_device.h> + +#include "coresight-config.h" +#include "coresight-syscfg.h" + +/* + * cscfg_ API manages configurations and features for the entire coresight + * infrastructure. + * + * It allows the loading of configurations and features, and loads these into + * coresight devices as appropriate. + */ + +/* protect the cscsg_data and device */ +static DEFINE_MUTEX(cscfg_mutex); + +/* only one of these */ +static struct cscfg_manager *cscfg_mgr; + +/* load features and configuations into the lists */ + +/* check feature list for a named feature - call with mutex locked. */ +static bool cscfg_match_list_feat(const char *name) +{ + struct cscfg_feature_desc *feat_desc; + + list_for_each_entry(feat_desc, &cscfg_mgr->feat_desc_list, item) { + if (strcmp(feat_desc->name, name) == 0) + return true; + } + return false; +} + +/* check all feat needed for cfg are in the list - call with mutex locked. */ +static int cscfg_check_feat_for_cfg(struct cscfg_config_desc *config_desc) +{ + int i; + + for (i = 0; i < config_desc->nr_feat_refs; i++) + if (!cscfg_match_list_feat(config_desc->feat_ref_names[i])) + return -EINVAL; + return 0; +} + +/* + * load feature - add to feature list. + */ +static int cscfg_load_feat(struct cscfg_feature_desc *feat_desc) +{ + list_add(&feat_desc->item, &cscfg_mgr->feat_desc_list); + + return 0; +} + +/* + * load config into the system - validate used features exist then add to + * config list. + */ +static int cscfg_load_config(struct cscfg_config_desc *config_desc) +{ + int err; + + /* validate features are present */ + err = cscfg_check_feat_for_cfg(config_desc); + if (err) + return err; + + list_add(&config_desc->item, &cscfg_mgr->config_desc_list); + return 0; +} + +/** + * cscfg_load_config_sets - API function to load feature and config sets. + * + * Take a 0 terminated array of feature descriptors and/or configuration + * descriptors and load into the system. + * Features are loaded first to ensure configuration dependencies can be met. + * + * @config_descs: 0 terminated array of configuration descriptors. + * @feat_descs: 0 terminated array of feature descriptors. + */ +int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, + struct cscfg_feature_desc **feat_descs) +{ + int err, i = 0; + + mutex_lock(&cscfg_mutex); + + /* load features first */ + if (feat_descs) { + while (feat_descs[i]) { + err = cscfg_load_feat(feat_descs[i]); + if (err) { + pr_err("coresight-syscfg: Failed to load feature %s\n", + feat_descs[i]->name); + goto exit_unlock; + } + i++; + } + } + + /* next any configurations to check feature dependencies */ + i = 0; + if (config_descs) { + while (config_descs[i]) { + err = cscfg_load_config(config_descs[i]); + if (err) { + pr_err("coresight-syscfg: Failed to load configuration %s\n", + config_descs[i]->name); + goto exit_unlock; + } + i++; + } + } + +exit_unlock: + mutex_unlock(&cscfg_mutex); + return err; +} +EXPORT_SYMBOL_GPL(cscfg_load_config_sets); + +/* Initialise system configuration management device. */ + +struct device *cscfg_device(void) +{ + return cscfg_mgr ? &cscfg_mgr->dev : NULL; +} + +/* Must have a release function or the kernel will complain on module unload */ +static void cscfg_dev_release(struct device *dev) +{ + kfree(cscfg_mgr); + cscfg_mgr = NULL; +} + +/* a device is needed to "own" some kernel elements such as sysfs entries. */ +static int cscfg_create_device(void) +{ + struct device *dev; + int err = -ENOMEM; + + mutex_lock(&cscfg_mutex); + if (cscfg_mgr) { + err = -EINVAL; + goto create_dev_exit_unlock; + } + + cscfg_mgr = kzalloc(sizeof(struct cscfg_manager), GFP_KERNEL); + if (!cscfg_mgr) + goto create_dev_exit_unlock; + + /* setup the device */ + dev = cscfg_device(); + dev->release = cscfg_dev_release; + dev->init_name = "cs_system_cfg"; + + err = device_register(dev); + if (err) + cscfg_dev_release(dev); + +create_dev_exit_unlock: + mutex_unlock(&cscfg_mutex); + return err; +} + +static void cscfg_clear_device(void) +{ + mutex_lock(&cscfg_mutex); + device_unregister(cscfg_device()); + mutex_unlock(&cscfg_mutex); +} + +/* Initialise system config management API device */ +int __init cscfg_init(void) +{ + int err = 0; + + err = cscfg_create_device(); + if (err) + return err; + + INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); + INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); + INIT_LIST_HEAD(&cscfg_mgr->config_desc_list); + + dev_info(cscfg_device(), "CoreSight Configuration manager initialised"); + return 0; +} + +void cscfg_exit(void) +{ + cscfg_clear_device(); +} diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h new file mode 100644 index 000000000000..18be9b58cd0b --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Coresight system configuration driver. + */ + +#ifndef CORESIGHT_SYSCFG_H +#define CORESIGHT_SYSCFG_H + +#include <linux/coresight.h> +#include <linux/device.h> + +#include "coresight-config.h" + +/** + * System configuration manager device. + * + * Contains lists of the loaded configurations and features, plus a list of CoreSight devices + * registered with the system as supporting configuration management. + * + * Need a device to 'own' some coresight system wide sysfs entries in + * perf events, configfs etc. + * + * @dev: The device. + * @csdev_desc_list: List of coresight devices registered with the configuration manager. + * @feat_desc_list: List of feature descriptors to load into registered devices. + * @config_desc_list: List of system configuration descriptors to load into registered devices. + */ +struct cscfg_manager { + struct device dev; + struct list_head csdev_desc_list; + struct list_head feat_desc_list; + struct list_head config_desc_list; +}; + +/* get reference to dev in cscfg_manager */ +struct device *cscfg_device(void); + +/* internal core operations for cscfg */ +int __init cscfg_init(void); +void cscfg_exit(void); + +/* syscfg manager external API */ +int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, + struct cscfg_feature_desc **feat_descs); + +#endif /* CORESIGHT_SYSCFG_H */

Adds a set of generic support functions that allow devices to set and save features values on the device, and enable and disable configurations.

Additional functions for other common operations including feature reset.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- drivers/hwtracing/coresight/Makefile | 2 +- .../hwtracing/coresight/coresight-config.c | 275 ++++++++++++++++++ .../hwtracing/coresight/coresight-config.h | 9 + .../hwtracing/coresight/coresight-syscfg.c | 3 +- 4 files changed, 287 insertions(+), 2 deletions(-) create mode 100644 drivers/hwtracing/coresight/coresight-config.c

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index 3d037f17aade..63ecfc3cf66d 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -4,7 +4,7 @@ # obj-$(CONFIG_CORESIGHT) += coresight.o coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \ - coresight-sysfs.o coresight-syscfg.o + coresight-sysfs.o coresight-syscfg.o coresight-config.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \ coresight-tmc-etr.o diff --git a/drivers/hwtracing/coresight/coresight-config.c b/drivers/hwtracing/coresight/coresight-config.c new file mode 100644 index 000000000000..3c501e027bc0 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-config.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(C) 2020 Linaro Limited. All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include <linux/sysfs.h> +#include "coresight-config.h" +#include "coresight-priv.h" + +/* + * This provides a set of generic functions that operate on configurations + * and features to manage the handling of parameters, the programming and + * saving of registers used by features on devices. + */ + +/* + * Write the value held in the register structure into the driver internal memory + * location. + */ +static void cscfg_set_reg(struct cscfg_regval_csdev *reg_csdev) +{ + u32 *p_val32 = (u32 *)reg_csdev->driver_regval; + u32 tmp32 = reg_csdev->reg_desc.val32; + + if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT) { + *((u64 *)reg_csdev->driver_regval) = reg_csdev->reg_desc.val64; + return; + } + + if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_MASK) { + tmp32 = *p_val32; + tmp32 &= ~reg_csdev->reg_desc.mask32; + tmp32 |= reg_csdev->reg_desc.val32 & reg_csdev->reg_desc.mask32; + } + *p_val32 = tmp32; +} + +/* + * Read the driver value into the reg if this is marked as one we want to save. + */ +static void cscfg_save_reg(struct cscfg_regval_csdev *reg_csdev) +{ + if (!(reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_SAVE)) + return; + if (reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT) + reg_csdev->reg_desc.val64 = *(u64 *)(reg_csdev->driver_regval); + else + reg_csdev->reg_desc.val32 = *(u32 *)(reg_csdev->driver_regval); +} + +/* + * Some register values are set from parameters. Initialise these registers + * from the current parameter values. + */ +static void cscfg_init_reg_param(struct cscfg_feature_csdev *feat_csdev, + struct cscfg_regval_desc *reg_desc, + struct cscfg_regval_csdev *reg_csdev) +{ + struct cscfg_parameter_csdev *param_csdev; + + /* for param, load routines have validated the index */ + param_csdev = &feat_csdev->params_csdev[reg_desc->param_idx]; + param_csdev->reg_csdev = reg_csdev; + param_csdev->val64 = reg_csdev->reg_desc.type & CS_CFG_REG_TYPE_VAL_64BIT; + + if (param_csdev->val64) + reg_csdev->reg_desc.val64 = param_csdev->current_value; + else + reg_csdev->reg_desc.val32 = (u32)param_csdev->current_value; +} + +/* set values into the driver locations referenced in cscfg_reg_csdev */ +static int cscfg_set_on_enable(struct cscfg_feature_csdev *feat_csdev) +{ + int i; + + spin_lock(feat_csdev->drv_spinlock); + for (i = 0; i < feat_csdev->nr_regs; i++) + cscfg_set_reg(&feat_csdev->regs_csdev[i]); + spin_unlock(feat_csdev->drv_spinlock); + dev_dbg(&feat_csdev->csdev->dev, "Feature %s: %s", + feat_csdev->feat_desc->name, "set on enable"); + return 0; +} + +/* copy back values from the driver locations referenced in cscfg_reg_csdev */ +static void cscfg_save_on_disable(struct cscfg_feature_csdev *feat_csdev) +{ + int i; + + spin_lock(feat_csdev->drv_spinlock); + for (i = 0; i < feat_csdev->nr_regs; i++) + cscfg_save_reg(&feat_csdev->regs_csdev[i]); + spin_unlock(feat_csdev->drv_spinlock); + dev_dbg(&feat_csdev->csdev->dev, "Feature %s: %s", + feat_csdev->feat_desc->name, "save on disable"); +} + +/* default reset - restore default values */ +void cscfg_reset_feat(struct cscfg_feature_csdev *feat_csdev) +{ + struct cscfg_regval_desc *reg_desc; + struct cscfg_regval_csdev *reg_csdev; + int i; + + /* + * set the default values for all parameters and regs from the + * relevant static descriptors. + */ + for (i = 0; i < feat_csdev->nr_params; i++) + feat_csdev->params_csdev[i].current_value = + feat_csdev->feat_desc->params_desc[i].value; + + for (i = 0; i < feat_csdev->nr_regs; i++) { + reg_desc = &feat_csdev->feat_desc->regs_desc[i]; + reg_csdev = &feat_csdev->regs_csdev[i]; + reg_csdev->reg_desc.type = reg_desc->type; + + /* check if reg set from a parameter otherwise desc default */ + if (reg_desc->type & CS_CFG_REG_TYPE_VAL_PARAM) + cscfg_init_reg_param(feat_csdev, reg_desc, reg_csdev); + else + /* + * for normal values the union between val64 & val32 + mask32 + * allows us to init using the 64 bit value + */ + reg_csdev->reg_desc.val64 = reg_desc->val64; + } +} + +/* + * For the selected presets, we set the register associated with the parameter, to + * the value of the preset index associated with the parameter. + */ +static int cscfg_update_presets(struct cscfg_config_csdev *config_csdev, int preset) +{ + int i, j, val_idx = 0, nr_cfg_params; + struct cscfg_parameter_csdev *param_csdev; + struct cscfg_feature_csdev *feat_csdev; + const struct cscfg_config_desc *config_desc = config_csdev->config_desc; + const char *name; + const u64 *preset_base; + u64 val; + + /* preset in range 1 to nr_presets */ + if (preset < 1 || preset > config_desc->nr_presets) + return -EINVAL; + /* + * Go through the array of features, assigning preset values to + * feature parameters in the order they appear. + * There should be precisely the same number of preset values as the + * sum of number of parameters over all the features - but we will + * ensure there is no overrun. + */ + nr_cfg_params = config_desc->nr_total_params; + preset_base = &config_desc->presets[(preset - 1) * nr_cfg_params]; + for (i = 0; i < config_csdev->nr_feat; i++) { + feat_csdev = config_csdev->feats_csdev[i]; + if (!feat_csdev->nr_params) + continue; + + for (j = 0; j < feat_csdev->nr_params; j++) { + param_csdev = &feat_csdev->params_csdev[j]; + name = feat_csdev->feat_desc->params_desc[j].name; + val = preset_base[val_idx++]; + if (param_csdev->val64) { + dev_dbg(&config_csdev->csdev->dev, + "set param %s (%lld)", name, val); + param_csdev->reg_csdev->reg_desc.val64 = val; + } else { + param_csdev->reg_csdev->reg_desc.val32 = (u32)val; + dev_dbg(&config_csdev->csdev->dev, + "set param %s (%d)", name, (u32)val); + } + } + + /* exit early if all params filled */ + if (val_idx >= nr_cfg_params) + break; + } + return 0; +} + +/* + * if we are not using a preset, then need to update the feature params + * with current values. This sets the register associated with the parameter + * with the current value of that parameter. + */ +static int cscfg_update_curr_params(struct cscfg_config_csdev *config_csdev) +{ + int i, j; + struct cscfg_feature_csdev *feat_csdev; + struct cscfg_parameter_csdev *param_csdev; + const char *name; + u64 val; + + for (i = 0; i < config_csdev->nr_feat; i++) { + feat_csdev = config_csdev->feats_csdev[i]; + if (!feat_csdev->nr_params) + continue; + for (j = 0; j < feat_csdev->nr_params; j++) { + param_csdev = &feat_csdev->params_csdev[j]; + name = feat_csdev->feat_desc->params_desc[j].name; + val = param_csdev->current_value; + if (param_csdev->val64) { + dev_dbg(&config_csdev->csdev->dev, + "set param %s (%lld)", name, val); + param_csdev->reg_csdev->reg_desc.val64 = val; + } else { + param_csdev->reg_csdev->reg_desc.val32 = (u32)val; + dev_dbg(&config_csdev->csdev->dev, + "set param %s (%d)", name, (u32)val); + } + } + } + return 0; +} + +/* + * Configuration values will be programmed into the driver locations if enabling, or read + * from relevant locations on disable. + */ +static int cscfg_prog_config(struct cscfg_config_csdev *config_csdev, bool enable) +{ + int i, err = 0; + struct cscfg_feature_csdev *feat_csdev; + struct coresight_device *csdev; + + for (i = 0; i < config_csdev->nr_feat; i++) { + feat_csdev = config_csdev->feats_csdev[i]; + csdev = feat_csdev->csdev; + dev_dbg(&csdev->dev, "cfg %s; %s feature:%s", config_csdev->config_desc->name, + enable ? "enable" : "disable", feat_csdev->feat_desc->name); + + if (enable) + err = cscfg_set_on_enable(feat_csdev); + else + cscfg_save_on_disable(feat_csdev); + + if (err) + break; + } + return err; +} + +/* + * Enable configuration for the device. Will result in the internal driver data + * being updated ready for programming into the device. + * + * @config_csdev: config_csdev to set. + * @preset: preset values to use - 0 for default. + */ +int cscfg_csdev_enable_config(struct cscfg_config_csdev *config_csdev, int preset) +{ + int err = 0; + + if (preset) + err = cscfg_update_presets(config_csdev, preset); + else + err = cscfg_update_curr_params(config_csdev); + if (!err) + err = cscfg_prog_config(config_csdev, true); + if (!err) + config_csdev->enabled = true; + return err; +} + +void cscfg_csdev_disable_config(struct cscfg_config_csdev *config_csdev) +{ + if (config_csdev->enabled) { + cscfg_prog_config(config_csdev, false); + config_csdev->enabled = false; + } +} diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 685fb46ce893..5a39cbbc38a4 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -237,4 +237,13 @@ struct cscfg_csdev_feat_ops { struct cscfg_feature_csdev *feat_csdev); };

+/* coresight config helper functions*/ + +/* enable / disable config on a device - called with appropriate locks set.*/ +int cscfg_csdev_enable_config(struct cscfg_config_csdev *config_csdev, int preset); +void cscfg_csdev_disable_config(struct cscfg_config_csdev *config_csdev); + +/* reset a feature to default values */ +void cscfg_reset_feat(struct cscfg_feature_csdev *feat_csdev); + #endif /* _CORESIGHT_CORESIGHT_CONFIG_H */ diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index e93e62c1efbb..c7f48d6b48f5 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -190,9 +190,10 @@ static int cscfg_load_feat_csdev(struct coresight_device *csdev, if (err) return err;

- /* add to internal csdev feature list */ + /* add to internal csdev feature list & initialise using reset call */ mutex_lock(&cscfg_csdev_mutex); list_add(&feat_csdev->node, &csdev->feature_csdev_list); + cscfg_reset_feat(feat_csdev); mutex_unlock(&cscfg_csdev_mutex);

return 0;

Configurations are first activated, then when any coresight device is enabled, the active configurations are checked and any matching one is enabled.

This patch provides the activation / enable API.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- .../hwtracing/coresight/coresight-config.h | 2 + .../hwtracing/coresight/coresight-syscfg.c | 172 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 8 + include/linux/coresight.h | 2 + 4 files changed, 184 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 0667581822c1..25eb6c632692 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -127,6 +127,7 @@ struct cscfg_feature_desc { * @nr_total_params: Sum of all parameters declared by used features * @presets: Array of preset values. * @event_ea: Extended attribute for perf event value + * @active_cnt: ref count for activate on this configuration. * */ struct cscfg_config_desc { @@ -139,6 +140,7 @@ struct cscfg_config_desc { int nr_total_params; const u64 *presets; /* nr_presets * nr_total_params */ struct dev_ext_attribute *event_ea; + atomic_t active_cnt; };

/** diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index e35f8c0ac2f8..b234e45c153f 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -283,6 +283,7 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return err;

list_add(&config_desc->item, &cscfg_mgr->config_desc_list); + atomic_set(&config_desc->active_cnt, 0); return 0; }

@@ -468,6 +469,176 @@ void cscfg_unregister_csdev(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);

+/** + * cscfg_csdev_reset_feats - reset features for a CoreSight device. + * + * Resets all parameters and register values for any features loaded + * into @csdev to their default values. + * + * @csdev: The CoreSight device. + */ +void cscfg_csdev_reset_feats(struct coresight_device *csdev) +{ + struct cscfg_feature_csdev *feat_csdev; + + mutex_lock(&cscfg_csdev_mutex); + if (list_empty(&csdev->feature_csdev_list)) + goto unlock_exit; + + list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node) + cscfg_reset_feat(feat_csdev); + +unlock_exit: + mutex_unlock(&cscfg_csdev_mutex); +} +EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats); + +/** + * cscfg_activate_config - Mark a configuration descriptor as active. + * + * This will be seen when csdev devices are enabled in the system. + * Only activated configurations can be enabled on individual devices. + * Activation protects the configuration from alteration or removal while + * active. + * + * Selection by hash value - generated from the configuration name when it + * was loaded and added to the cs_etm/configurations file system for selection + * by perf. + * + * Increments the configuration descriptor active count and the global active + * count. + * + * @cfg_hash: Hash value of the selected configuration name. + */ +int cscfg_activate_config(unsigned long cfg_hash) +{ + struct cscfg_config_desc *config_desc; + int err = -EINVAL; + + mutex_lock(&cscfg_mutex); + + list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) { + if ((unsigned long)config_desc->event_ea->var == cfg_hash) { + /* + * increment the global active count - control changes to + * active configurations + */ + atomic_inc(&cscfg_mgr->sys_active_cnt); + + /* + * mark the descriptor as active so enable config on a + * device instance will use it + */ + atomic_inc(&config_desc->active_cnt); + + err = 0; + dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name); + break; + } + } + mutex_unlock(&cscfg_mutex); + + return err; +} +EXPORT_SYMBOL_GPL(cscfg_activate_config); + +/** + * cscfg_deactivate_config - Mark a config descriptor as inactive. + * + * Decrement the configuration and global active counts. + * + * @cfg_hash: Hash value of the selected configuration name. + */ +void cscfg_deactivate_config(unsigned long cfg_hash) +{ + struct cscfg_config_desc *config_desc; + + mutex_lock(&cscfg_mutex); + + list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) { + if ((unsigned long)config_desc->event_ea->var == cfg_hash) { + atomic_dec(&config_desc->active_cnt); + atomic_dec(&cscfg_mgr->sys_active_cnt); + dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name); + break; + } + } + mutex_unlock(&cscfg_mutex); +} +EXPORT_SYMBOL_GPL(cscfg_deactivate_config); + +/** + * cscfg_csdev_enable_active_config - Enable matching active configuration for device. + * + * Enables the configuration selected by @cfg_hash if the configuration is supported + * on the device and has been activated. + * + * If active and supported the CoreSight device @csdev will be programmed with the + * configuration, using @preset parameters. + * + * Should be called before driver hardware enable for the requested device, prior to + * programming and enabling the physical hardware. + * + * @csdev: CoreSight device to program. + * @cfg_hash: Selector for the configuration. + * @preset: Preset parameter values to use, 0 for current / default values. + */ +int cscfg_csdev_enable_active_config(struct coresight_device *csdev, + unsigned long cfg_hash, int preset) +{ + struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item; + const struct cscfg_config_desc *config_desc; + int err = 0; + + /* quickly check global count */ + if (!atomic_read(&cscfg_mgr->sys_active_cnt)) + return 0; + + mutex_lock(&cscfg_csdev_mutex); + list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) { + config_desc = config_csdev_item->config_desc; + if ((atomic_read(&config_desc->active_cnt)) && + ((unsigned long)config_desc->event_ea->var == cfg_hash)) { + config_csdev_active = config_csdev_item; + break; + } + } + if (config_csdev_active) { + err = cscfg_csdev_enable_config(config_csdev_active, preset); + if (!err) + csdev->active_cscfg_ctxt = (void *)config_csdev_active; + } + mutex_unlock(&cscfg_csdev_mutex); + return err; +} +EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config); + +/** + * cscfg_csdev_disable_active_config - disable an active config on the device. + * + * Disables the active configuration on the CoreSight device @csdev. + * Disable will save the values of any registers marked in the configurations + * as save on disable. + * + * Should be called after driver hardware disable for the requested device, + * after disabling the physical hardware and reading back registers. + * + * @csdev: The CoreSight device. + */ +void cscfg_csdev_disable_active_config(struct coresight_device *csdev) +{ + struct cscfg_config_csdev *config_csdev; + + mutex_lock(&cscfg_csdev_mutex); + config_csdev = (struct cscfg_config_csdev *)csdev->active_cscfg_ctxt; + if (config_csdev) { + cscfg_csdev_disable_config(config_csdev); + csdev->active_cscfg_ctxt = NULL; + } + mutex_unlock(&cscfg_csdev_mutex); +} +EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config); + /* Initialise system configuration management device. */

struct device *cscfg_device(void) @@ -536,6 +707,7 @@ int __init cscfg_init(void) INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list); + atomic_set(&cscfg_mgr->sys_active_cnt, 0);

dev_info(cscfg_device(), "CoreSight Configuration manager initialised"); return 0; diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 5bcae3b374c6..a52775890670 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -24,12 +24,14 @@ * @csdev_desc_list: List of coresight devices registered with the configuration manager. * @feat_desc_list: List of feature descriptors to load into registered devices. * @config_desc_list: List of system configuration descriptors to load into registered devices. + * @sys_active_cnt: Total number of active config descriptor references. */ struct cscfg_manager { struct device dev; struct list_head csdev_desc_list; struct list_head feat_desc_list; struct list_head config_desc_list; + atomic_t sys_active_cnt; };

/* get reference to dev in cscfg_manager */ @@ -61,5 +63,11 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags, struct cscfg_csdev_feat_ops *ops); void cscfg_unregister_csdev(struct coresight_device *csdev); +int cscfg_activate_config(unsigned long cfg_hash); +void cscfg_deactivate_config(unsigned long cfg_hash); +void cscfg_csdev_reset_feats(struct coresight_device *csdev); +int cscfg_csdev_enable_active_config(struct coresight_device *csdev, + unsigned long cfg_hash, int preset); +void cscfg_csdev_disable_active_config(struct coresight_device *csdev);

#endif /* CORESIGHT_SYSCFG_H */ diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 6fb516e1b22e..a348049ee08b 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -222,6 +222,7 @@ struct coresight_sysfs_link { * @has_conns_grp: Have added a "connections" group for sysfs links. * @feature_csdev_list: List of complex feature programming added to the device. * @config_csdev_list: List of system configurations added to the device. + * @active_cscfg_ctxt: Context information for current active system configuration. */ struct coresight_device { struct coresight_platform_data *pdata; @@ -246,6 +247,7 @@ struct coresight_device { /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list; + void *active_cscfg_ctxt; };

/*

Adds in handlers to allow the ETMv4 to use the complex configuration support. Features and configurations can be loaded and selected in the device.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- drivers/hwtracing/coresight/Makefile | 3 +- .../hwtracing/coresight/coresight-etm4x-cfg.c | 182 ++++++++++++++++++ .../hwtracing/coresight/coresight-etm4x-cfg.h | 15 ++ .../coresight/coresight-etm4x-core.c | 38 +++- .../coresight/coresight-etm4x-sysfs.c | 3 + 5 files changed, 238 insertions(+), 3 deletions(-) create mode 100644 drivers/hwtracing/coresight/coresight-etm4x-cfg.c create mode 100644 drivers/hwtracing/coresight/coresight-etm4x-cfg.h

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index 63ecfc3cf66d..9420d33b23ac 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -16,7 +16,8 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm3x-y := coresight-etm3x-core.o coresight-etm-cp14.o \ coresight-etm3x-sysfs.o obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o -coresight-etm4x-y := coresight-etm4x-core.o coresight-etm4x-sysfs.o +coresight-etm4x-y := coresight-etm4x-core.o coresight-etm4x-sysfs.o \ + coresight-etm4x-cfg.o obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o diff --git a/drivers/hwtracing/coresight/coresight-etm4x-cfg.c b/drivers/hwtracing/coresight/coresight-etm4x-cfg.c new file mode 100644 index 000000000000..d2ea903231b2 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-etm4x-cfg.c @@ -0,0 +1,182 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(C) 2020 Linaro Limited. All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include "coresight-etm4x.h" +#include "coresight-etm4x-cfg.h" +#include "coresight-priv.h" +#include "coresight-syscfg.h" + +/* defines to associate register IDs with driver data locations */ +#define CHECKREG(cval, elem) \ + { \ + if (offset == cval) { \ + reg_csdev->driver_regval = &drvcfg->elem; \ + err = 0; \ + break; \ + } \ + } + +#define CHECKREGIDX(cval, elem, off_idx, mask) \ + { \ + if (mask == cval) { \ + reg_csdev->driver_regval = &drvcfg->elem[off_idx]; \ + err = 0; \ + break; \ + } \ + } + +/** + * etm4_cfg_map_reg_offset - validate and map the register offset into a + * location in the driver config struct. + * + * Limits the number of registers that can be accessed and programmed in + * features, to those which are used to control the trace capture parameters. + * + * Omits or limits access to those which the driver must use exclusively. + * + * Invalid offsets will result in fail code return and feature load failure. + * + * @drvdata: driver data to map into. + * @reg: register to map. + * @offset: device offset for the register + */ +static int etm4_cfg_map_reg_offset(struct etmv4_drvdata *drvdata, + struct cscfg_regval_csdev *reg_csdev, u32 offset) +{ + int err = -EINVAL, idx; + struct etmv4_config *drvcfg = &drvdata->config; + u32 off_mask; + + if (((offset >= TRCEVENTCTL0R) && (offset <= TRCVIPCSSCTLR)) || + ((offset >= TRCSEQRSTEVR) && (offset <= TRCEXTINSELR)) || + ((offset >= TRCCIDCCTLR0) && (offset <= TRCVMIDCCTLR1))) { + do { + CHECKREG(TRCEVENTCTL0R, eventctrl0); + CHECKREG(TRCEVENTCTL1R, eventctrl1); + CHECKREG(TRCSTALLCTLR, stall_ctrl); + CHECKREG(TRCTSCTLR, ts_ctrl); + CHECKREG(TRCSYNCPR, syncfreq); + CHECKREG(TRCCCCTLR, ccctlr); + CHECKREG(TRCBBCTLR, bb_ctrl); + CHECKREG(TRCVICTLR, vinst_ctrl); + CHECKREG(TRCVIIECTLR, viiectlr); + CHECKREG(TRCVISSCTLR, vissctlr); + CHECKREG(TRCVIPCSSCTLR, vipcssctlr); + CHECKREG(TRCSEQRSTEVR, seq_rst); + CHECKREG(TRCSEQSTR, seq_state); + CHECKREG(TRCEXTINSELR, ext_inp); + CHECKREG(TRCCIDCCTLR0, ctxid_mask0); + CHECKREG(TRCCIDCCTLR1, ctxid_mask1); + CHECKREG(TRCVMIDCCTLR0, vmid_mask0); + CHECKREG(TRCVMIDCCTLR1, vmid_mask1); + } while (0); + } else if ((offset & GENMASK(11, 4)) == TRCSEQEVRn(0)) { + /* sequencer state control registers */ + idx = (offset & GENMASK(3, 0)) / 4; + if (idx < ETM_MAX_SEQ_STATES) { + reg_csdev->driver_regval = &drvcfg->seq_ctrl[idx]; + err = 0; + } + } else if ((offset >= TRCSSCCRn(0)) && (offset <= TRCSSPCICRn(7))) { + /* 32 bit, 8 off indexed register sets */ + idx = (offset & GENMASK(4, 0)) / 4; + off_mask = (offset & GENMASK(11, 5)); + do { + CHECKREGIDX(TRCSSCCRn(0), ss_ctrl, idx, off_mask); + CHECKREGIDX(TRCSSCSRn(0), ss_status, idx, off_mask); + CHECKREGIDX(TRCSSPCICRn(0), ss_pe_cmp, idx, off_mask); + } while (0); + } else if ((offset >= TRCCIDCVRn(0)) && (offset <= TRCVMIDCVRn(7))) { + /* 64 bit, 8 off indexed register sets */ + idx = (offset & GENMASK(5, 0)) / 8; + off_mask = (offset & GENMASK(11, 6)); + do { + CHECKREGIDX(TRCCIDCVRn(0), ctxid_pid, idx, off_mask); + CHECKREGIDX(TRCVMIDCVRn(0), vmid_val, idx, off_mask); + } while (0); + } else if ((offset >= TRCRSCTLRn(2)) && + (offset <= TRCRSCTLRn((ETM_MAX_RES_SEL - 1)))) { + /* 32 bit resource selection regs, 32 off, skip fixed 0,1 */ + idx = (offset & GENMASK(6, 0)) / 4; + if (idx < ETM_MAX_RES_SEL) { + reg_csdev->driver_regval = &drvcfg->res_ctrl[idx]; + err = 0; + } + } else if ((offset >= TRCACVRn(0)) && + (offset <= TRCACATRn((ETM_MAX_SINGLE_ADDR_CMP - 1)))) { + /* 64 bit addr cmp regs, 16 off */ + idx = (offset & GENMASK(6, 0)) / 8; + off_mask = offset & GENMASK(11, 7); + do { + CHECKREGIDX(TRCACVRn(0), addr_val, idx, off_mask); + CHECKREGIDX(TRCACATRn(0), addr_acc, idx, off_mask); + } while (0); + } else if ((offset >= TRCCNTRLDVRn(0)) && + (offset <= TRCCNTVRn((ETMv4_MAX_CNTR - 1)))) { + /* 32 bit counter regs, 4 off (ETMv4_MAX_CNTR - 1) */ + idx = (offset & GENMASK(3, 0)) / 4; + off_mask = offset & GENMASK(11, 4); + do { + CHECKREGIDX(TRCCNTRLDVRn(0), cntrldvr, idx, off_mask); + CHECKREGIDX(TRCCNTCTLRn(0), cntr_ctrl, idx, off_mask); + CHECKREGIDX(TRCCNTVRn(0), cntr_val, idx, off_mask); + } while (0); + } + return err; +} + +/** + * etm4_cfg_load_feature - load a feature into a device instance. + * + * @csdev: An ETMv4 CoreSight device. + * @feat: The feature to be loaded. + * + * The function will load a feature instance into the device, checking that + * the register definitions are valid for the device. + * + * Parameter and register definitions will be converted into internal + * structures that are used to set the values in the driver when the + * feature is enabled for the device. + * + * The feature spinlock pointer is initialised to the same spinlock + * that the driver uses to protect the internal register values. + */ +static int etm4_cfg_load_feature(struct coresight_device *csdev, + struct cscfg_feature_csdev *feat_csdev) +{ + struct device *dev = csdev->dev.parent; + struct etmv4_drvdata *drvdata = dev_get_drvdata(dev); + const struct cscfg_feature_desc *feat_desc = feat_csdev->feat_desc; + u32 offset; + int i = 0, err = 0; + + /* + * essential we set the device spinlock - this is used in the generic + * programming routines when copying values into the drvdata structures + * via the pointers setup in etm4_cfg_map_reg_offset(). + */ + feat_csdev->drv_spinlock = &drvdata->spinlock; + + /* process the register descriptions */ + for (i = 0; i < feat_csdev->nr_regs && !err; i++) { + offset = feat_desc->regs_desc[i].offset; + err = etm4_cfg_map_reg_offset(drvdata, &feat_csdev->regs_csdev[i], offset); + } + return err; +} + +/* match information when loading configurations */ +#define CS_CFG_ETM4_MATCH_FLAGS (CS_CFG_MATCH_CLASS_SRC_ALL | \ + CS_CFG_MATCH_CLASS_SRC_ETM4) + +int etm4_cscfg_register(struct coresight_device *csdev) +{ + struct cscfg_csdev_feat_ops ops; + + ops.load_feat = &etm4_cfg_load_feature; + + return cscfg_register_csdev(csdev, CS_CFG_ETM4_MATCH_FLAGS, &ops); +} diff --git a/drivers/hwtracing/coresight/coresight-etm4x-cfg.h b/drivers/hwtracing/coresight/coresight-etm4x-cfg.h new file mode 100644 index 000000000000..a204ad9a4792 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-etm4x-cfg.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2014-2020, The Linux Foundation. All rights reserved. + */ + +#ifndef _CORESIGHT_ETM4X_CFG_H +#define _CORESIGHT_ETM4X_CFG_H + +#include "coresight-config.h" +#include "coresight-etm4x.h" + +/* ETMv4 specific config functions */ +int etm4_cscfg_register(struct coresight_device *csdev); + +#endif /* CORESIGHT_ETM4X_CFG_H */ diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index efb84ced83dd..94f10910d20d 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -39,6 +39,8 @@

#include "coresight-etm4x.h" #include "coresight-etm-perf.h" +#include "coresight-etm4x-cfg.h" +#include "coresight-syscfg.h"

static int boot_enable; module_param(boot_enable, int, 0444); @@ -561,12 +563,15 @@ static int etm4_config_timestamp_event(struct etmv4_drvdata *drvdata) return ret; }

-static int etm4_parse_event_config(struct etmv4_drvdata *drvdata, +static int etm4_parse_event_config(struct coresight_device *csdev, struct perf_event *event) { int ret = 0; + struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); struct etmv4_config *config = &drvdata->config; struct perf_event_attr *attr = &event->attr; + unsigned long cfg_hash; + int preset;

if (!attr) { ret = -EINVAL; @@ -637,6 +642,20 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata, /* bit[12], Return stack enable bit */ config->cfg |= BIT(12);

+ /* + * Set any selected configuration and preset. + * + * This extracts the values of PMU_FORMAT_ATTR(configid) and PMU_FORMAT_ATTR(preset) + * in the perf attributes defined in coresight-etm-perf.c. + * configid uses bits 63:32 of attr->config2, preset uses bits 3:0 of attr->config. + * A zero configid means no configuration active, preset = 0 means no preset selected. + */ + if (attr->config2 & GENMASK_ULL(63, 32)) { + cfg_hash = (u32)(attr->config2 >> 32); + preset = attr->config & 0xF; + ret = cscfg_csdev_enable_active_config(csdev, cfg_hash, preset); + } + out: return ret; } @@ -653,7 +672,7 @@ static int etm4_enable_perf(struct coresight_device *csdev, }

/* Configure the tracer based on the session's specifics */ - ret = etm4_parse_event_config(drvdata, event); + ret = etm4_parse_event_config(csdev, event); if (ret) goto out; /* And enable it */ @@ -799,11 +818,18 @@ static int etm4_disable_perf(struct coresight_device *csdev, u32 control; struct etm_filters *filters = event->hw.addr_filters; struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + struct perf_event_attr *attr = &event->attr;

if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) return -EINVAL;

etm4_disable_hw(drvdata); + /* + * The config_id occupies bits 63:32 of the config2 perf event attr + * field. If this is non-zero then we will have enabled a config. + */ + if (attr->config2 & GENMASK_ULL(63, 32)) + cscfg_csdev_disable_active_config(csdev);

/* * Check if the start/stop logic was active when the unit was stopped. @@ -1944,6 +1970,13 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid) return ret; }

+ /* register with config infrastructure & load any current features */ + ret = etm4_cscfg_register(drvdata->csdev); + if (ret) { + coresight_unregister(drvdata->csdev); + return ret; + } + etmdrvdata[drvdata->cpu] = drvdata;

dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n", @@ -2030,6 +2063,7 @@ static int __exit etm4_remove_dev(struct etmv4_drvdata *drvdata)

cpus_read_unlock();

+ cscfg_unregister_csdev(drvdata->csdev); coresight_unregister(drvdata->csdev);

return 0; diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c index 007bad9e7ad8..a0640fa5c55b 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c @@ -9,6 +9,7 @@ #include <linux/sysfs.h> #include "coresight-etm4x.h" #include "coresight-priv.h" +#include "coresight-syscfg.h"

static int etm4_set_mode_exclude(struct etmv4_drvdata *drvdata, bool exclude) { @@ -269,6 +270,8 @@ static ssize_t reset_store(struct device *dev,

spin_unlock(&drvdata->spinlock);

+ cscfg_csdev_reset_feats(to_coresight_device(dev)); + return size; } static DEVICE_ATTR_WO(reset);

Adds configfs subsystem and attributes to the configuration manager to enable the listing of loaded configurations and features.

The default values of feature parameters can be accessed and altered from these attributes to affect all installed devices using the feature.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- drivers/hwtracing/coresight/Makefile | 3 +- .../coresight/coresight-syscfg-configfs.c | 396 ++++++++++++++++++ .../coresight/coresight-syscfg-configfs.h | 45 ++ .../hwtracing/coresight/coresight-syscfg.c | 76 ++++ .../hwtracing/coresight/coresight-syscfg.h | 7 + 5 files changed, 526 insertions(+), 1 deletion(-) create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.c create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.h

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index ad44f0fe3069..b6c4a48140ec 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -5,7 +5,8 @@ obj-$(CONFIG_CORESIGHT) += coresight.o coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \ coresight-sysfs.o coresight-syscfg.o coresight-config.o \ - coresight-cfg-preload.o coresight-cfg-afdo.o + coresight-cfg-preload.o coresight-cfg-afdo.o \ + coresight-syscfg-configfs.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \ coresight-tmc-etr.o diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c new file mode 100644 index 000000000000..c547816b9000 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c @@ -0,0 +1,396 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include <linux/configfs.h> + +#include "coresight-syscfg-configfs.h" + +/* create a default ci_type. */ +static inline struct config_item_type *cscfg_create_ci_type(void) +{ + struct config_item_type *ci_type; + + ci_type = devm_kzalloc(cscfg_device(), sizeof(*ci_type), GFP_KERNEL); + if (ci_type) + ci_type->ct_owner = THIS_MODULE; + + return ci_type; +} + +/* configurations sub-group */ + +/* attributes for the config view group */ +static ssize_t cscfg_cfg_description_show(struct config_item *item, char *page) +{ + struct cscfg_fs_config *fs_config = container_of(to_config_group(item), + struct cscfg_fs_config, group); + + return scnprintf(page, PAGE_SIZE, "%s", fs_config->config_desc->description); +} +CONFIGFS_ATTR_RO(cscfg_cfg_, description); + +static ssize_t cscfg_cfg_feature_refs_show(struct config_item *item, char *page) +{ + struct cscfg_fs_config *fs_config = container_of(to_config_group(item), + struct cscfg_fs_config, group); + const struct cscfg_config_desc *config_desc = fs_config->config_desc; + ssize_t ch_used = 0; + int i; + + for (i = 0; i < config_desc->nr_feat_refs; i++) + ch_used += scnprintf(page + ch_used, PAGE_SIZE - ch_used, + "%s\n", config_desc->feat_ref_names[i]); + return ch_used; +} +CONFIGFS_ATTR_RO(cscfg_cfg_, feature_refs); + +/* list preset values in order of features and params */ +static ssize_t cscfg_cfg_values_show(struct config_item *item, char *page) +{ + const struct cscfg_feature_desc *feat_desc; + const struct cscfg_config_desc *config_desc; + struct cscfg_fs_preset *fs_preset; + int i, j, val_idx, preset_idx; + ssize_t used = 0; + + fs_preset = container_of(to_config_group(item), struct cscfg_fs_preset, group); + config_desc = fs_preset->config_desc; + + if (!config_desc->nr_presets) + return 0; + + preset_idx = fs_preset->preset_num - 1; + + /* start index on the correct array line */ + val_idx = config_desc->nr_total_params * preset_idx; + + /* + * A set of presets is the sum of all params in used features, + * in order of declaration of features and params in the features + */ + for (i = 0; i < config_desc->nr_feat_refs; i++) { + feat_desc = cscfg_get_named_feat_desc(config_desc->feat_ref_names[i]); + for (j = 0; j < feat_desc->nr_params; j++) { + used += scnprintf(page + used, PAGE_SIZE - used, + "%s.%s = 0x%llx ", + feat_desc->name, + feat_desc->params_desc[j].name, + config_desc->presets[val_idx++]); + } + } + used += scnprintf(page + used, PAGE_SIZE - used, "\n"); + + return used; +} +CONFIGFS_ATTR_RO(cscfg_cfg_, values); + +static struct configfs_attribute *cscfg_config_view_attrs[] = { + &cscfg_cfg_attr_description, + &cscfg_cfg_attr_feature_refs, + NULL, +}; + +static struct config_item_type cscfg_config_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_config_view_attrs, +}; + +static struct configfs_attribute *cscfg_config_preset_attrs[] = { + &cscfg_cfg_attr_values, + NULL, +}; + +static struct config_item_type cscfg_config_preset_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_config_preset_attrs, +}; + +static int cscfg_add_preset_groups(struct cscfg_fs_config *cfg_view) +{ + int preset_num; + struct cscfg_fs_preset *cfg_fs_preset; + struct cscfg_config_desc *config_desc = cfg_view->config_desc; + char name[CONFIGFS_ITEM_NAME_LEN]; + + if (!config_desc->nr_presets) + return 0; + + for (preset_num = 1; preset_num <= config_desc->nr_presets; preset_num++) { + cfg_fs_preset = devm_kzalloc(cscfg_device(), + sizeof(struct cscfg_fs_preset), GFP_KERNEL); + + if (!cfg_fs_preset) + return -ENOMEM; + + snprintf(name, CONFIGFS_ITEM_NAME_LEN, "preset%d", preset_num); + cfg_fs_preset->preset_num = preset_num; + cfg_fs_preset->config_desc = cfg_view->config_desc; + config_group_init_type_name(&cfg_fs_preset->group, name, + &cscfg_config_preset_type); + configfs_add_default_group(&cfg_fs_preset->group, &cfg_view->group); + } + return 0; +} + +static struct config_group *cscfg_create_config_group(struct cscfg_config_desc *config_desc) +{ + struct cscfg_fs_config *cfg_view; + struct device *dev = cscfg_device(); + int err; + + if (!dev) + return ERR_PTR(-EINVAL); + + cfg_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_config), GFP_KERNEL); + if (!cfg_view) + return ERR_PTR(-ENOMEM); + + cfg_view->config_desc = config_desc; + config_group_init_type_name(&cfg_view->group, config_desc->name, &cscfg_config_view_type); + + /* add in a preset<n> dir for each preset */ + err = cscfg_add_preset_groups(cfg_view); + if (err) + return ERR_PTR(err); + + return &cfg_view->group; +} + +/* attributes for features view */ + +static ssize_t cscfg_feat_description_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + + return scnprintf(page, PAGE_SIZE, "%s", fs_feat->feat_desc->description); +} +CONFIGFS_ATTR_RO(cscfg_feat_, description); + +static ssize_t cscfg_feat_matches_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + u32 match_flags = fs_feat->feat_desc->match_flags; + int used = 0; + + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ALL) + used = scnprintf(page, PAGE_SIZE, "SRC_ALL "); + + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ETM4) + used += scnprintf(page + used, PAGE_SIZE - used, "SRC_ETMV4 "); + + used += scnprintf(page + used, PAGE_SIZE - used, "\n"); + return used; +} +CONFIGFS_ATTR_RO(cscfg_feat_, matches); + +static ssize_t cscfg_feat_nr_params_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + + return scnprintf(page, PAGE_SIZE, "%d\n", fs_feat->feat_desc->nr_params); +} +CONFIGFS_ATTR_RO(cscfg_feat_, nr_params); + +/* base feature desc attrib structures */ +static struct configfs_attribute *cscfg_feature_view_attrs[] = { + &cscfg_feat_attr_description, + &cscfg_feat_attr_matches, + &cscfg_feat_attr_nr_params, + NULL, +}; + +static struct config_item_type cscfg_feature_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_feature_view_attrs, +}; + +static ssize_t cscfg_param_value_show(struct config_item *item, char *page) +{ + struct cscfg_fs_param *param_item = container_of(to_config_group(item), + struct cscfg_fs_param, group); + u64 value = param_item->feat_desc->params_desc[param_item->param_idx].value; + + return scnprintf(page, PAGE_SIZE, "0x%llx\n", value); +} + +static ssize_t cscfg_param_value_store(struct config_item *item, + const char *page, size_t size) +{ + struct cscfg_fs_param *param_item = container_of(to_config_group(item), + struct cscfg_fs_param, group); + struct cscfg_feature_desc *feat_desc = param_item->feat_desc; + int param_idx = param_item->param_idx; + u64 value; + int err; + + err = kstrtoull(page, 0, &value); + if (!err) + err = cscfg_update_feat_param_val(feat_desc, param_idx, value); + + return err ? err : size; +} +CONFIGFS_ATTR(cscfg_param_, value); + +static struct configfs_attribute *cscfg_param_view_attrs[] = { + &cscfg_param_attr_value, + NULL, +}; + +static struct config_item_type cscfg_param_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_param_view_attrs, +}; + +/* + * configfs has far less functionality provided to add attributes dynamically than sysfs, + * and the show and store fns pass the enclosing config_item so the actual attribute cannot + * be determined. Therefore we add each item as a group directory, with a value attribute. + */ +static int cscfg_create_params_group_items(struct cscfg_feature_desc *feat_desc, + struct config_group *params_group) +{ + struct device *dev = cscfg_device(); + struct cscfg_fs_param *param_item; + int i; + + /* parameter items - as groups with default_value attribute */ + for (i = 0; i < feat_desc->nr_params; i++) { + param_item = devm_kzalloc(dev, sizeof(struct cscfg_fs_param), GFP_KERNEL); + if (!param_item) + return -ENOMEM; + param_item->feat_desc = feat_desc; + param_item->param_idx = i; + config_group_init_type_name(&param_item->group, + feat_desc->params_desc[i].name, + &cscfg_param_view_type); + configfs_add_default_group(&param_item->group, params_group); + } + return 0; +} + +static struct config_group *cscfg_create_feature_group(struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_fs_feature *feat_view; + struct config_item_type *params_group_type; + struct config_group *params_group = NULL; + struct device *dev = cscfg_device(); + int item_err; + + if (!dev) + return ERR_PTR(-EINVAL); + + feat_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_feature), GFP_KERNEL); + if (!feat_view) + return ERR_PTR(-ENOMEM); + + if (feat_desc->nr_params) { + params_group = devm_kzalloc(dev, sizeof(struct config_group), GFP_KERNEL); + if (!params_group) + return ERR_PTR(-ENOMEM); + + params_group_type = cscfg_create_ci_type(); + if (!params_group_type) + return ERR_PTR(-ENOMEM); + } + + feat_view->feat_desc = feat_desc; + config_group_init_type_name(&feat_view->group, + feat_desc->name, + &cscfg_feature_view_type); + if (params_group) { + config_group_init_type_name(params_group, "params", params_group_type); + configfs_add_default_group(params_group, &feat_view->group); + item_err = cscfg_create_params_group_items(feat_desc, params_group); + if (item_err) + return ERR_PTR(item_err); + } + return &feat_view->group; +} + +static struct config_item_type cscfg_configs_type = { + .ct_owner = THIS_MODULE, +}; + +static struct config_group cscfg_configs_grp = { + .cg_item = { + .ci_namebuf = "configurations", + .ci_type = &cscfg_configs_type, + }, +}; + +/* add configuration to configurations group */ +int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc) +{ + struct config_group *new_group; + int err; + + new_group = cscfg_create_config_group(config_desc); + if (IS_ERR(new_group)) + return PTR_ERR(new_group); + err = configfs_register_group(&cscfg_configs_grp, new_group); + return err; +} + +static struct config_item_type cscfg_features_type = { + .ct_owner = THIS_MODULE, +}; + +static struct config_group cscfg_features_grp = { + .cg_item = { + .ci_namebuf = "features", + .ci_type = &cscfg_features_type, + }, +}; + +/* add feature to features group */ +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc) +{ + struct config_group *new_group; + int err; + + new_group = cscfg_create_feature_group(feat_desc); + if (IS_ERR(new_group)) + return PTR_ERR(new_group); + err = configfs_register_group(&cscfg_features_grp, new_group); + return err; +} + +int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr) +{ + struct configfs_subsystem *subsys; + struct config_item_type *ci_type; + + if (!cscfg_mgr) + return -EINVAL; + + ci_type = cscfg_create_ci_type(); + if (!ci_type) + return -ENOMEM; + + subsys = &cscfg_mgr->cfgfs_subsys; + config_item_set_name(&subsys->su_group.cg_item, CSCFG_FS_SUBSYS_NAME); + subsys->su_group.cg_item.ci_type = ci_type; + + config_group_init(&subsys->su_group); + mutex_init(&subsys->su_mutex); + + /* Add default groups to subsystem */ + config_group_init(&cscfg_configs_grp); + configfs_add_default_group(&cscfg_configs_grp, &subsys->su_group); + + config_group_init(&cscfg_features_grp); + configfs_add_default_group(&cscfg_features_grp, &subsys->su_group); + + return configfs_register_subsystem(subsys); +} + +void cscfg_configfs_release(struct cscfg_manager *cscfg_mgr) +{ + configfs_unregister_subsystem(&cscfg_mgr->cfgfs_subsys); +} diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.h b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h new file mode 100644 index 000000000000..7d6ffe35ca4c --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Coresight system configuration driver - support for configfs. + */ + +#ifndef CORESIGHT_SYSCFG_CONFIGFS_H +#define CORESIGHT_SYSCFG_CONFIGFS_H + +#include <linux/configfs.h> +#include "coresight-syscfg.h" + +#define CSCFG_FS_SUBSYS_NAME "cs-syscfg" + +/* container for configuration view */ +struct cscfg_fs_config { + struct cscfg_config_desc *config_desc; + struct config_group group; +}; + +/* container for feature view */ +struct cscfg_fs_feature { + struct cscfg_feature_desc *feat_desc; + struct config_group group; +}; + +/* container for parameter view */ +struct cscfg_fs_param { + int param_idx; + struct cscfg_feature_desc *feat_desc; + struct config_group group; +}; + +/* container for preset view */ +struct cscfg_fs_preset { + int preset_num; + struct cscfg_config_desc *config_desc; + struct config_group group; +}; + +int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr); +void cscfg_configfs_release(struct cscfg_manager *cscfg_mgr); +int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc); +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc); + +#endif /* CORESIGHT_SYSCFG_CONFIGFS_H */ diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index 41f742190639..180202402eb5 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -9,6 +9,7 @@ #include "coresight-config.h" #include "coresight-etm-perf.h" #include "coresight-syscfg.h" +#include "coresight-syscfg-configfs.h"

/* * cscfg_ API manages configurations and features for the entire coresight @@ -287,6 +288,72 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return 0; }

+/* get a feature descriptor by name */ +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name) +{ + const struct cscfg_feature_desc *feat_desc = NULL, *feat_desc_item; + + mutex_lock(&cscfg_mutex); + + list_for_each_entry(feat_desc_item, &cscfg_mgr->feat_desc_list, item) { + if (strcmp(feat_desc_item->name, name) == 0) { + feat_desc = feat_desc_item; + break; + } + } + + mutex_unlock(&cscfg_mutex); + return feat_desc; +} + +/* called with cscfg_mutex held */ +static struct cscfg_feature_csdev * +cscfg_csdev_get_feat_from_desc(struct coresight_device *csdev, + struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_feature_csdev *feat_csdev; + + list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node) { + if (feat_csdev->feat_desc == feat_desc) + return feat_csdev; + } + return NULL; +} + +int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc, + int param_idx, u64 value) +{ + int err = 0; + struct cscfg_feature_csdev *feat_csdev; + struct cscfg_registered_csdev *csdev_item; + + mutex_lock(&cscfg_mutex); + + /* check if any config active & return busy */ + if (atomic_read(&cscfg_mgr->sys_active_cnt)) { + err = -EBUSY; + goto unlock_exit; + } + + /* set the value */ + if ((param_idx < 0) || (param_idx >= feat_desc->nr_params)) { + err = -EINVAL; + goto unlock_exit; + } + feat_desc->params_desc[param_idx].value = value; + + /* update loaded instances.*/ + list_for_each_entry(csdev_item, &cscfg_mgr->csdev_desc_list, item) { + feat_csdev = cscfg_csdev_get_feat_from_desc(csdev_item->csdev, feat_desc); + if (feat_csdev) + feat_csdev->params_csdev[param_idx].current_value = value; + } + +unlock_exit: + mutex_unlock(&cscfg_mutex); + return err; +} + /** * cscfg_load_config_sets - API function to load feature and config sets. * @@ -308,6 +375,8 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, if (feat_descs) { while (feat_descs[i]) { err = cscfg_load_feat(feat_descs[i]); + if (!err) + err = cscfg_configfs_add_feature(feat_descs[i]); if (err) { pr_err("coresight-syscfg: Failed to load feature %s\n", feat_descs[i]->name); @@ -322,6 +391,8 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, if (config_descs) { while (config_descs[i]) { err = cscfg_load_config(config_descs[i]); + if (!err) + err = cscfg_configfs_add_config(config_descs[i]); if (err) { pr_err("coresight-syscfg: Failed to load configuration %s\n", config_descs[i]->name); @@ -691,6 +762,7 @@ static void cscfg_clear_device(void) list_for_each_entry(cfg_desc, &cscfg_mgr->config_desc_list, item) { etm_perf_del_symlink_cscfg(cfg_desc); } + cscfg_configfs_release(cscfg_mgr); device_unregister(cscfg_device()); mutex_unlock(&cscfg_mutex); } @@ -704,6 +776,10 @@ int __init cscfg_init(void) if (err) return err;

+ err = cscfg_configfs_init(cscfg_mgr); + if (err) + goto exit_err; + INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list); diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 7bb8c8e497ba..8d018efd6ead 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -6,6 +6,7 @@ #ifndef CORESIGHT_SYSCFG_H #define CORESIGHT_SYSCFG_H

+#include <linux/configfs.h> #include <linux/coresight.h> #include <linux/device.h>

@@ -25,6 +26,7 @@ * @feat_desc_list: List of feature descriptors to load into registered devices. * @config_desc_list: List of system configuration descriptors to load into registered devices. * @sys_active_cnt: Total number of active config descriptor references. + * @cfgfs_subsys: configfs subsystem used to manage configurations. */ struct cscfg_manager { struct device dev; @@ -32,6 +34,7 @@ struct cscfg_manager { struct list_head feat_desc_list; struct list_head config_desc_list; atomic_t sys_active_cnt; + struct configfs_subsystem cfgfs_subsys; };

/* get reference to dev in cscfg_manager */ @@ -57,6 +60,10 @@ struct cscfg_registered_csdev { int __init cscfg_init(void); void cscfg_exit(void); int cscfg_preload(void); +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name); +int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc, + int param_idx, u64 value); +

/* syscfg manager external API */ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,

Hi Branislav,

On Thu, 10 Jun 2021 at 05:05, Branislav Rankov branislav.rankov@arm.com wrote:

On 4/14/21 8:18 PM, Mike Leach wrote:

...

Configurations are first activated, then when any coresight device is enabled, the active configurations are checked and any matching one is enabled.

This patch provides the activation / enable API.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org

---

.../hwtracing/coresight/coresight-config.h | 2 + .../hwtracing/coresight/coresight-syscfg.c | 172 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 8 + include/linux/coresight.h | 2 + 4 files changed, 184 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 0667581822c1..25eb6c632692 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -127,6 +127,7 @@ struct cscfg_feature_desc {

• @nr_total_params: Sum of all parameters declared by used features
• @presets: Array of preset values.
• @event_ea: Extended attribute for perf event value

• • @active_cnt: ref count for activate on this configuration.
  */ struct cscfg_config_desc {

@@ -139,6 +140,7 @@ struct cscfg_config_desc { int nr_total_params; const u64 *presets; /* nr_presets * nr_total_params */ struct dev_ext_attribute *event_ea;

• atomic_t active_cnt;
  

  };

  /**

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index e35f8c0ac2f8..b234e45c153f 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -283,6 +283,7 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return err;

  list_add(&config_desc->item, &cscfg_mgr->config_desc_list);

• atomic_set(&config_desc->active_cnt, 0);
  return 0;
  

  }

@@ -468,6 +469,176 @@ void cscfg_unregister_csdev(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);

+/**

• • cscfg_csdev_reset_feats - reset features for a CoreSight device.
• • Resets all parameters and register values for any features loaded
• • into @csdev to their default values.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_reset_feats(struct coresight_device *csdev) +{

• struct cscfg_feature_csdev *feat_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• if (list_empty(&csdev->feature_csdev_list))
  

•         goto unlock_exit;
  

• list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node)
  

•         cscfg_reset_feat(feat_csdev);
  

+unlock_exit:

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats);

+/**

• • cscfg_activate_config - Mark a configuration descriptor as active.
• • This will be seen when csdev devices are enabled in the system.
• • Only activated configurations can be enabled on individual devices.
• • Activation protects the configuration from alteration or removal while
• • active.
• • Selection by hash value - generated from the configuration name when it
• • was loaded and added to the cs_etm/configurations file system for selection
• • by perf.
• • Increments the configuration descriptor active count and the global active
• • count.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+int cscfg_activate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• int err = -EINVAL;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 /*
  

•                  * increment the global active count - control changes to
  

•                  * active configurations
  

•                  */
  

•                 atomic_inc(&cscfg_mgr->sys_active_cnt);
  

•                 /*
  

•                  * mark the descriptor as active so enable config on a
  

•                  * device instance will use it
  

•                  */
  

•                 atomic_inc(&config_desc->active_cnt);
  

•                 err = 0;
  

•                 dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_activate_config);

+/**

• • cscfg_deactivate_config - Mark a config descriptor as inactive.
• • Decrement the configuration and global active counts.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+void cscfg_deactivate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 atomic_dec(&config_desc->active_cnt);
  

•                 atomic_dec(&cscfg_mgr->sys_active_cnt);
  

•                 dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_deactivate_config);

+/**

• • cscfg_csdev_enable_active_config - Enable matching active configuration for device.
• • Enables the configuration selected by @cfg_hash if the configuration is supported
• • on the device and has been activated.
• • If active and supported the CoreSight device @csdev will be programmed with the
• • configuration, using @preset parameters.
• • Should be called before driver hardware enable for the requested device, prior to
• • programming and enabling the physical hardware.
• • @csdev: CoreSight device to program.
• • @cfg_hash: Selector for the configuration.
• • @preset: Preset parameter values to use, 0 for current / default values.
• */

+int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset)
  

+{

• struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item;
  

• const struct cscfg_config_desc *config_desc;
  

• int err = 0;
  

• /* quickly check global count */
  

• if (!atomic_read(&cscfg_mgr->sys_active_cnt))
  

•         return 0;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) {
  

•         config_desc = config_csdev_item->config_desc;
  

•         if ((atomic_read(&config_desc->active_cnt)) &&
  

•             ((unsigned long)config_desc->event_ea->var == cfg_hash)) {
  

•                 config_csdev_active = config_csdev_item;
  

•                 break;
  

•         }
  

• }
  

• if (config_csdev_active) {
  

•         err = cscfg_csdev_enable_config(config_csdev_active, preset);
  

•         if (!err)
  

•                 csdev->active_cscfg_ctxt = (void *)config_csdev_active;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config);

+/**

• • cscfg_csdev_disable_active_config - disable an active config on the device.
• • Disables the active configuration on the CoreSight device @csdev.
• • Disable will save the values of any registers marked in the configurations
• • as save on disable.
• • Should be called after driver hardware disable for the requested device,
• • after disabling the physical hardware and reading back registers.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev) +{

• struct cscfg_config_csdev *config_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

This line seems to cause a bug report when the kernel is compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y

I have tested this by applying the series to 5.10 kernel on Dragonboard 845c.

It only happens when strobing is used.

Thanks for reporting this. Unfortunately Mike is away and likely won't be able to look at this in time for the merge window. As such I backed out the complex configuration feature from the next branch but that code is still available on next-complex-configuration.

Thanks, Mathieu

The report is this:

[13431.885395] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 [13431.893919] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 3525, name: perf [13431.901882] CPU: 0 PID: 3525 Comm: perf Tainted: G W 5.10.0-rc5-17282-g923b456a55fb #124 [13431.911436] Hardware name: Thundercomm Dragonboard 845c (DT) [13431.917450] Call trace: [13431.919938] dump_backtrace+0x0/0x1a0 [13431.923644] show_stack+0x18/0x68 [13431.927008] dump_stack+0xd0/0x12c [13431.930444] ___might_sleep+0xf0/0x130 [13431.934228] __might_sleep+0x54/0x90 [13431.937945] mutex_lock+0x28/0x80 [13431.941468] cscfg_csdev_disable_active_config+0x24/0x50 [13431.946952] etm4_disable+0xf0/0x100 [13431.950571] etm_event_stop+0xb8/0x130 [13431.954380] etm_event_del+0x14/0x20 [13431.958008] event_sched_out.isra.0+0x84/0x1c8 [13431.962496] group_sched_out.part.0+0x44/0xc8 [13431.967010] __perf_event_disable+0xe4/0x198 [13431.971549] event_function+0x8c/0xe8 [13431.975256] remote_function+0x64/0x78 [13431.979161] generic_exec_single+0xa0/0x100 [13431.983876] smp_call_function_single+0x158/0x1d8 [13431.988629] event_function_call+0x128/0x138 [13431.992942] _perf_event_disable+0x48/0x70 [13431.997082] perf_event_for_each_child+0x3c/0x90 [13432.001751] _perf_ioctl+0x198/0x4a8 [13432.005359] perf_ioctl+0x4c/0x78 [13432.008715] __arm64_sys_ioctl+0xa8/0xf0 [13432.012835] el0_svc_common.constprop.0+0x78/0x1a0 [13432.017767] do_el0_svc+0x24/0x90 [13432.021616] el0_sync_handler+0x160/0x168 [13432.025670] el0_sync+0x174/0x180

...

• config_csdev = (struct cscfg_config_csdev *)csdev->active_cscfg_ctxt;
  

• if (config_csdev) {
  

•         cscfg_csdev_disable_config(config_csdev);
  

•         csdev->active_cscfg_ctxt = NULL;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config);

• /* Initialise system configuration management device. */

  struct device *cscfg_device(void)

@@ -536,6 +707,7 @@ int __init cscfg_init(void) INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list);

• atomic_set(&cscfg_mgr->sys_active_cnt, 0);
  
  dev_info(cscfg_device(), "CoreSight Configuration manager initialised");
  return 0;
  

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 5bcae3b374c6..a52775890670 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -24,12 +24,14 @@

• @csdev_desc_list: List of coresight devices registered with the configuration manager.
• @feat_desc_list: List of feature descriptors to load into registered devices.
• @config_desc_list: List of system configuration descriptors to load into registered devices.

• • @sys_active_cnt: Total number of active config descriptor references.

  */ struct cscfg_manager { struct device dev; struct list_head csdev_desc_list; struct list_head feat_desc_list; struct list_head config_desc_list;

• atomic_t sys_active_cnt;
  

  };

  /* get reference to dev in cscfg_manager */

@@ -61,5 +63,11 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags, struct cscfg_csdev_feat_ops *ops); void cscfg_unregister_csdev(struct coresight_device *csdev); +int cscfg_activate_config(unsigned long cfg_hash); +void cscfg_deactivate_config(unsigned long cfg_hash); +void cscfg_csdev_reset_feats(struct coresight_device *csdev); +int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset);
  

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev);

#endif /* CORESIGHT_SYSCFG_H */ diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 6fb516e1b22e..a348049ee08b 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -222,6 +222,7 @@ struct coresight_sysfs_link {

• @has_conns_grp: Have added a "connections" group for sysfs links.
• @feature_csdev_list: List of complex feature programming added to the device.
• @config_csdev_list: List of system configurations added to the device.

• • @active_cscfg_ctxt: Context information for current active system configuration.
  */ struct coresight_device { struct coresight_platform_data *pdata;

@@ -246,6 +247,7 @@ struct coresight_device { /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list;

• void *active_cscfg_ctxt;
  

  };

  /*

On 25/06/2021 15:37, Mike Leach wrote:

HI Branislav, Mathieu,

I have started to look into this as a top priority.

However, when I enable the CONFIG_DEBUG_ option my board fails to boot at all. (Dragonboard DB410c), so the resolution make take a little time.

At this point I am assuming that the mutex will need to be replaced by a spinlock - so a re-design + v8 set may well be required.

Or may be a refcount on the "config" instance may work too ? i.e, when the config is loaded onto a device, a refcount could be taken on the config and dropped on unload.

Whoever drops it to zero could release it.

Thoughts ?

Suzuki

Regards

Mike

On Mon, 14 Jun 2021 at 18:03, Mathieu Poirier mathieu.poirier@linaro.org wrote:

...

Hi Branislav,

On Thu, 10 Jun 2021 at 05:05, Branislav Rankov branislav.rankov@arm.com wrote:

...

On 4/14/21 8:18 PM, Mike Leach wrote:

...

Configurations are first activated, then when any coresight device is enabled, the active configurations are checked and any matching one is enabled.

This patch provides the activation / enable API.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org

---

.../hwtracing/coresight/coresight-config.h | 2 + .../hwtracing/coresight/coresight-syscfg.c | 172 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 8 + include/linux/coresight.h | 2 + 4 files changed, 184 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 0667581822c1..25eb6c632692 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -127,6 +127,7 @@ struct cscfg_feature_desc { * @nr_total_params: Sum of all parameters declared by used features * @presets: Array of preset values. * @event_ea: Extended attribute for perf event value

• • @active_cnt: ref count for activate on this configuration.
    */
  struct cscfg_config_desc {

@@ -139,6 +140,7 @@ struct cscfg_config_desc { int nr_total_params; const u64 *presets; /* nr_presets * nr_total_params */ struct dev_ext_attribute *event_ea;

• atomic_t active_cnt;
  

  };

  /**

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index e35f8c0ac2f8..b234e45c153f 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -283,6 +283,7 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return err;

   list_add(&config_desc->item, &cscfg_mgr->config_desc_list);

• atomic_set(&config_desc->active_cnt, 0);
   return 0;
  

  }

@@ -468,6 +469,176 @@ void cscfg_unregister_csdev(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);

+/**

• • cscfg_csdev_reset_feats - reset features for a CoreSight device.
• • Resets all parameters and register values for any features loaded
• • into @csdev to their default values.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_reset_feats(struct coresight_device *csdev) +{

• struct cscfg_feature_csdev *feat_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• if (list_empty(&csdev->feature_csdev_list))
  

•         goto unlock_exit;
  

• list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node)
  

•         cscfg_reset_feat(feat_csdev);
  

+unlock_exit:

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats);

+/**

• • cscfg_activate_config - Mark a configuration descriptor as active.
• • This will be seen when csdev devices are enabled in the system.
• • Only activated configurations can be enabled on individual devices.
• • Activation protects the configuration from alteration or removal while
• • active.
• • Selection by hash value - generated from the configuration name when it
• • was loaded and added to the cs_etm/configurations file system for selection
• • by perf.
• • Increments the configuration descriptor active count and the global active
• • count.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+int cscfg_activate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• int err = -EINVAL;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 /*
  

•                  * increment the global active count - control changes to
  

•                  * active configurations
  

•                  */
  

•                 atomic_inc(&cscfg_mgr->sys_active_cnt);
  

•                 /*
  

•                  * mark the descriptor as active so enable config on a
  

•                  * device instance will use it
  

•                  */
  

•                 atomic_inc(&config_desc->active_cnt);
  

•                 err = 0;
  

•                 dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_activate_config);

+/**

• • cscfg_deactivate_config - Mark a config descriptor as inactive.
• • Decrement the configuration and global active counts.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+void cscfg_deactivate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 atomic_dec(&config_desc->active_cnt);
  

•                 atomic_dec(&cscfg_mgr->sys_active_cnt);
  

•                 dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_deactivate_config);

+/**

• • cscfg_csdev_enable_active_config - Enable matching active configuration for device.
• • Enables the configuration selected by @cfg_hash if the configuration is supported
• • on the device and has been activated.
• • If active and supported the CoreSight device @csdev will be programmed with the
• • configuration, using @preset parameters.
• • Should be called before driver hardware enable for the requested device, prior to
• • programming and enabling the physical hardware.
• • @csdev: CoreSight device to program.
• • @cfg_hash: Selector for the configuration.
• • @preset: Preset parameter values to use, 0 for current / default values.
• */

+int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset)
  

+{

• struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item;
  

• const struct cscfg_config_desc *config_desc;
  

• int err = 0;
  

• /* quickly check global count */
  

• if (!atomic_read(&cscfg_mgr->sys_active_cnt))
  

•         return 0;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) {
  

•         config_desc = config_csdev_item->config_desc;
  

•         if ((atomic_read(&config_desc->active_cnt)) &&
  

•             ((unsigned long)config_desc->event_ea->var == cfg_hash)) {
  

•                 config_csdev_active = config_csdev_item;
  

•                 break;
  

•         }
  

• }
  

• if (config_csdev_active) {
  

•         err = cscfg_csdev_enable_config(config_csdev_active, preset);
  

•         if (!err)
  

•                 csdev->active_cscfg_ctxt = (void *)config_csdev_active;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config);

+/**

• • cscfg_csdev_disable_active_config - disable an active config on the device.
• • Disables the active configuration on the CoreSight device @csdev.
• • Disable will save the values of any registers marked in the configurations
• • as save on disable.
• • Should be called after driver hardware disable for the requested device,
• • after disabling the physical hardware and reading back registers.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev) +{

• struct cscfg_config_csdev *config_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

This line seems to cause a bug report when the kernel is compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y

I have tested this by applying the series to 5.10 kernel on Dragonboard 845c.

It only happens when strobing is used.

Thanks for reporting this. Unfortunately Mike is away and likely won't be able to look at this in time for the merge window. As such I backed out the complex configuration feature from the next branch but that code is still available on next-complex-configuration.

Thanks, Mathieu

...

The report is this:

[13431.885395] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 [13431.893919] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 3525, name: perf [13431.901882] CPU: 0 PID: 3525 Comm: perf Tainted: G W 5.10.0-rc5-17282-g923b456a55fb #124 [13431.911436] Hardware name: Thundercomm Dragonboard 845c (DT) [13431.917450] Call trace: [13431.919938] dump_backtrace+0x0/0x1a0 [13431.923644] show_stack+0x18/0x68 [13431.927008] dump_stack+0xd0/0x12c [13431.930444] ___might_sleep+0xf0/0x130 [13431.934228] __might_sleep+0x54/0x90 [13431.937945] mutex_lock+0x28/0x80 [13431.941468] cscfg_csdev_disable_active_config+0x24/0x50 [13431.946952] etm4_disable+0xf0/0x100 [13431.950571] etm_event_stop+0xb8/0x130 [13431.954380] etm_event_del+0x14/0x20 [13431.958008] event_sched_out.isra.0+0x84/0x1c8 [13431.962496] group_sched_out.part.0+0x44/0xc8 [13431.967010] __perf_event_disable+0xe4/0x198 [13431.971549] event_function+0x8c/0xe8 [13431.975256] remote_function+0x64/0x78 [13431.979161] generic_exec_single+0xa0/0x100 [13431.983876] smp_call_function_single+0x158/0x1d8 [13431.988629] event_function_call+0x128/0x138 [13431.992942] _perf_event_disable+0x48/0x70 [13431.997082] perf_event_for_each_child+0x3c/0x90 [13432.001751] _perf_ioctl+0x198/0x4a8 [13432.005359] perf_ioctl+0x4c/0x78 [13432.008715] __arm64_sys_ioctl+0xa8/0xf0 [13432.012835] el0_svc_common.constprop.0+0x78/0x1a0 [13432.017767] do_el0_svc+0x24/0x90 [13432.021616] el0_sync_handler+0x160/0x168 [13432.025670] el0_sync+0x174/0x180

...

• config_csdev = (struct cscfg_config_csdev *)csdev->active_cscfg_ctxt;
  

• if (config_csdev) {
  

•         cscfg_csdev_disable_config(config_csdev);
  

•         csdev->active_cscfg_ctxt = NULL;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config);

• /* Initialise system configuration management device. */

  struct device *cscfg_device(void)

@@ -536,6 +707,7 @@ int __init cscfg_init(void) INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list);

• atomic_set(&cscfg_mgr->sys_active_cnt, 0);
  
   dev_info(cscfg_device(), "CoreSight Configuration manager initialised");
   return 0;
  

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 5bcae3b374c6..a52775890670 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -24,12 +24,14 @@ * @csdev_desc_list: List of coresight devices registered with the configuration manager. * @feat_desc_list: List of feature descriptors to load into registered devices. * @config_desc_list: List of system configuration descriptors to load into registered devices.

• • @sys_active_cnt: Total number of active config descriptor references. */

  struct cscfg_manager { struct device dev; struct list_head csdev_desc_list; struct list_head feat_desc_list; struct list_head config_desc_list;

• atomic_t sys_active_cnt;
  

  };

  /* get reference to dev in cscfg_manager */

@@ -61,5 +63,11 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags, struct cscfg_csdev_feat_ops *ops); void cscfg_unregister_csdev(struct coresight_device *csdev); +int cscfg_activate_config(unsigned long cfg_hash); +void cscfg_deactivate_config(unsigned long cfg_hash); +void cscfg_csdev_reset_feats(struct coresight_device *csdev); +int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset);
  

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev);

#endif /* CORESIGHT_SYSCFG_H */ diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 6fb516e1b22e..a348049ee08b 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -222,6 +222,7 @@ struct coresight_sysfs_link { * @has_conns_grp: Have added a "connections" group for sysfs links. * @feature_csdev_list: List of complex feature programming added to the device. * @config_csdev_list: List of system configurations added to the device.

• • @active_cscfg_ctxt: Context information for current active system configuration. */
  struct coresight_device { struct coresight_platform_data *pdata;

@@ -246,6 +247,7 @@ struct coresight_device { /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list;

• void *active_cscfg_ctxt;
  

  };

  /*

On Fri, Jun 25, 2021 at 03:37:16PM +0100, Mike Leach wrote:

HI Branislav, Mathieu,

I have started to look into this as a top priority.

Perfect.

There was also a report from a build bot realted to an undefined reference to config_group_init_type_name(). Please see if there is something to do on that one as well - I haven't had the opportunity to look at the report.

Thanks, Mathieu

However, when I enable the CONFIG_DEBUG_ option my board fails to boot at all. (Dragonboard DB410c), so the resolution make take a little time.

At this point I am assuming that the mutex will need to be replaced by a spinlock - so a re-design + v8 set may well be required.

Regards

Mike

On Mon, 14 Jun 2021 at 18:03, Mathieu Poirier mathieu.poirier@linaro.org wrote:

...

Hi Branislav,

On Thu, 10 Jun 2021 at 05:05, Branislav Rankov branislav.rankov@arm.com wrote:

...

On 4/14/21 8:18 PM, Mike Leach wrote:

...

Configurations are first activated, then when any coresight device is enabled, the active configurations are checked and any matching one is enabled.

This patch provides the activation / enable API.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org

---

.../hwtracing/coresight/coresight-config.h | 2 + .../hwtracing/coresight/coresight-syscfg.c | 172 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 8 + include/linux/coresight.h | 2 + 4 files changed, 184 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 0667581822c1..25eb6c632692 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -127,6 +127,7 @@ struct cscfg_feature_desc {

• @nr_total_params: Sum of all parameters declared by used features
• @presets: Array of preset values.
• @event_ea: Extended attribute for perf event value

• • @active_cnt: ref count for activate on this configuration.
  */ struct cscfg_config_desc {

@@ -139,6 +140,7 @@ struct cscfg_config_desc { int nr_total_params; const u64 *presets; /* nr_presets * nr_total_params */ struct dev_ext_attribute *event_ea;

• atomic_t active_cnt;
  

  };

  /**

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index e35f8c0ac2f8..b234e45c153f 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -283,6 +283,7 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return err;

  list_add(&config_desc->item, &cscfg_mgr->config_desc_list);

• atomic_set(&config_desc->active_cnt, 0);
  return 0;
  

  }

@@ -468,6 +469,176 @@ void cscfg_unregister_csdev(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);

+/**

• • cscfg_csdev_reset_feats - reset features for a CoreSight device.
• • Resets all parameters and register values for any features loaded
• • into @csdev to their default values.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_reset_feats(struct coresight_device *csdev) +{

• struct cscfg_feature_csdev *feat_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• if (list_empty(&csdev->feature_csdev_list))
  

•         goto unlock_exit;
  

• list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node)
  

•         cscfg_reset_feat(feat_csdev);
  

+unlock_exit:

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats);

+/**

• • cscfg_activate_config - Mark a configuration descriptor as active.
• • This will be seen when csdev devices are enabled in the system.
• • Only activated configurations can be enabled on individual devices.
• • Activation protects the configuration from alteration or removal while
• • active.
• • Selection by hash value - generated from the configuration name when it
• • was loaded and added to the cs_etm/configurations file system for selection
• • by perf.
• • Increments the configuration descriptor active count and the global active
• • count.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+int cscfg_activate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• int err = -EINVAL;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 /*
  

•                  * increment the global active count - control changes to
  

•                  * active configurations
  

•                  */
  

•                 atomic_inc(&cscfg_mgr->sys_active_cnt);
  

•                 /*
  

•                  * mark the descriptor as active so enable config on a
  

•                  * device instance will use it
  

•                  */
  

•                 atomic_inc(&config_desc->active_cnt);
  

•                 err = 0;
  

•                 dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_activate_config);

+/**

• • cscfg_deactivate_config - Mark a config descriptor as inactive.
• • Decrement the configuration and global active counts.
• • @cfg_hash: Hash value of the selected configuration name.
• */

+void cscfg_deactivate_config(unsigned long cfg_hash) +{

• struct cscfg_config_desc *config_desc;
  

• mutex_lock(&cscfg_mutex);
  

• list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
  

•         if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
  

•                 atomic_dec(&config_desc->active_cnt);
  

•                 atomic_dec(&cscfg_mgr->sys_active_cnt);
  

•                 dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
  

•                 break;
  

•         }
  

• }
  

• mutex_unlock(&cscfg_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_deactivate_config);

+/**

• • cscfg_csdev_enable_active_config - Enable matching active configuration for device.
• • Enables the configuration selected by @cfg_hash if the configuration is supported
• • on the device and has been activated.
• • If active and supported the CoreSight device @csdev will be programmed with the
• • configuration, using @preset parameters.
• • Should be called before driver hardware enable for the requested device, prior to
• • programming and enabling the physical hardware.
• • @csdev: CoreSight device to program.
• • @cfg_hash: Selector for the configuration.
• • @preset: Preset parameter values to use, 0 for current / default values.
• */

+int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset)
  

+{

• struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item;
  

• const struct cscfg_config_desc *config_desc;
  

• int err = 0;
  

• /* quickly check global count */
  

• if (!atomic_read(&cscfg_mgr->sys_active_cnt))
  

•         return 0;
  

• mutex_lock(&cscfg_csdev_mutex);
  

• list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) {
  

•         config_desc = config_csdev_item->config_desc;
  

•         if ((atomic_read(&config_desc->active_cnt)) &&
  

•             ((unsigned long)config_desc->event_ea->var == cfg_hash)) {
  

•                 config_csdev_active = config_csdev_item;
  

•                 break;
  

•         }
  

• }
  

• if (config_csdev_active) {
  

•         err = cscfg_csdev_enable_config(config_csdev_active, preset);
  

•         if (!err)
  

•                 csdev->active_cscfg_ctxt = (void *)config_csdev_active;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

• return err;
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config);

+/**

• • cscfg_csdev_disable_active_config - disable an active config on the device.
• • Disables the active configuration on the CoreSight device @csdev.
• • Disable will save the values of any registers marked in the configurations
• • as save on disable.
• • Should be called after driver hardware disable for the requested device,
• • after disabling the physical hardware and reading back registers.
• • @csdev: The CoreSight device.
• */

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev) +{

• struct cscfg_config_csdev *config_csdev;
  

• mutex_lock(&cscfg_csdev_mutex);
  

This line seems to cause a bug report when the kernel is compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y

I have tested this by applying the series to 5.10 kernel on Dragonboard 845c.

It only happens when strobing is used.

Thanks for reporting this. Unfortunately Mike is away and likely won't be able to look at this in time for the merge window. As such I backed out the complex configuration feature from the next branch but that code is still available on next-complex-configuration.

Thanks, Mathieu

...

The report is this:

[13431.885395] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283 [13431.893919] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 3525, name: perf [13431.901882] CPU: 0 PID: 3525 Comm: perf Tainted: G W 5.10.0-rc5-17282-g923b456a55fb #124 [13431.911436] Hardware name: Thundercomm Dragonboard 845c (DT) [13431.917450] Call trace: [13431.919938] dump_backtrace+0x0/0x1a0 [13431.923644] show_stack+0x18/0x68 [13431.927008] dump_stack+0xd0/0x12c [13431.930444] ___might_sleep+0xf0/0x130 [13431.934228] __might_sleep+0x54/0x90 [13431.937945] mutex_lock+0x28/0x80 [13431.941468] cscfg_csdev_disable_active_config+0x24/0x50 [13431.946952] etm4_disable+0xf0/0x100 [13431.950571] etm_event_stop+0xb8/0x130 [13431.954380] etm_event_del+0x14/0x20 [13431.958008] event_sched_out.isra.0+0x84/0x1c8 [13431.962496] group_sched_out.part.0+0x44/0xc8 [13431.967010] __perf_event_disable+0xe4/0x198 [13431.971549] event_function+0x8c/0xe8 [13431.975256] remote_function+0x64/0x78 [13431.979161] generic_exec_single+0xa0/0x100 [13431.983876] smp_call_function_single+0x158/0x1d8 [13431.988629] event_function_call+0x128/0x138 [13431.992942] _perf_event_disable+0x48/0x70 [13431.997082] perf_event_for_each_child+0x3c/0x90 [13432.001751] _perf_ioctl+0x198/0x4a8 [13432.005359] perf_ioctl+0x4c/0x78 [13432.008715] __arm64_sys_ioctl+0xa8/0xf0 [13432.012835] el0_svc_common.constprop.0+0x78/0x1a0 [13432.017767] do_el0_svc+0x24/0x90 [13432.021616] el0_sync_handler+0x160/0x168 [13432.025670] el0_sync+0x174/0x180

...

• config_csdev = (struct cscfg_config_csdev *)csdev->active_cscfg_ctxt;
  

• if (config_csdev) {
  

•         cscfg_csdev_disable_config(config_csdev);
  

•         csdev->active_cscfg_ctxt = NULL;
  

• }
  

• mutex_unlock(&cscfg_csdev_mutex);
  

+} +EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config);

• /* Initialise system configuration management device. */

  struct device *cscfg_device(void)

@@ -536,6 +707,7 @@ int __init cscfg_init(void) INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list);

• atomic_set(&cscfg_mgr->sys_active_cnt, 0);
  
  dev_info(cscfg_device(), "CoreSight Configuration manager initialised");
  return 0;
  

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 5bcae3b374c6..a52775890670 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -24,12 +24,14 @@

• @csdev_desc_list: List of coresight devices registered with the configuration manager.
• @feat_desc_list: List of feature descriptors to load into registered devices.
• @config_desc_list: List of system configuration descriptors to load into registered devices.

• • @sys_active_cnt: Total number of active config descriptor references.

  */ struct cscfg_manager { struct device dev; struct list_head csdev_desc_list; struct list_head feat_desc_list; struct list_head config_desc_list;

• atomic_t sys_active_cnt;
  

  };

  /* get reference to dev in cscfg_manager */

@@ -61,5 +63,11 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags, struct cscfg_csdev_feat_ops *ops); void cscfg_unregister_csdev(struct coresight_device *csdev); +int cscfg_activate_config(unsigned long cfg_hash); +void cscfg_deactivate_config(unsigned long cfg_hash); +void cscfg_csdev_reset_feats(struct coresight_device *csdev); +int cscfg_csdev_enable_active_config(struct coresight_device *csdev,

•                              unsigned long cfg_hash, int preset);
  

+void cscfg_csdev_disable_active_config(struct coresight_device *csdev);

#endif /* CORESIGHT_SYSCFG_H */ diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 6fb516e1b22e..a348049ee08b 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -222,6 +222,7 @@ struct coresight_sysfs_link {

• @has_conns_grp: Have added a "connections" group for sysfs links.
• @feature_csdev_list: List of complex feature programming added to the device.
• @config_csdev_list: List of system configurations added to the device.

• • @active_cscfg_ctxt: Context information for current active system configuration.
  */ struct coresight_device { struct coresight_platform_data *pdata;

@@ -246,6 +247,7 @@ struct coresight_device { /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list;

• void *active_cscfg_ctxt;
  

  };

  /*

-- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK