Add in functionality to allow load via configfs.
Define a binary file format and provide a reader for that format that will create and populate configuration and feature structures use by the driver infrastructure.
Adds API to access new functionality.
Signed-off-by: Mike Leach mike.leach@linaro.org --- drivers/hwtracing/coresight/Makefile | 2 +- .../coresight/coresight-config-file.c | 520 ++++++++++++++++++ .../coresight/coresight-config-file.h | 139 +++++ .../hwtracing/coresight/coresight-config.h | 15 + .../hwtracing/coresight/coresight-syscfg.h | 1 + 5 files changed, 676 insertions(+), 1 deletion(-) create mode 100644 drivers/hwtracing/coresight/coresight-config-file.c create mode 100644 drivers/hwtracing/coresight/coresight-config-file.h
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index b6c4a48140ec..5de2bb79f4ac 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -6,7 +6,7 @@ obj-$(CONFIG_CORESIGHT) += coresight.o coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \ coresight-sysfs.o coresight-syscfg.o coresight-config.o \ coresight-cfg-preload.o coresight-cfg-afdo.o \ - coresight-syscfg-configfs.o + coresight-syscfg-configfs.o coresight-config-file.o obj-$(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-file.c b/drivers/hwtracing/coresight/coresight-config-file.c new file mode 100644 index 000000000000..be11261e3a14 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-config-file.c @@ -0,0 +1,520 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include "coresight-config.h" +#include "coresight-config-file.h" + +#define cscfg_extract_u64(val64) { \ + val64 = *(u64 *)(buffer + used); \ + used += sizeof(u64); \ + } + +#define cscfg_extract_u32(val32) { \ + val32 = *(u32 *)(buffer + used); \ + used += sizeof(u32); \ + } + +#define cscfg_extract_u16(val16) { \ + val16 = *(u16 *)(buffer + used); \ + used += sizeof(u16); \ + } + +#define cscfg_extract_u8(val8) { \ + val8 = *(buffer + used); \ + used++; \ + } + +static int cscfg_file_read_hdr(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_file_header *hdr) +{ + /* file header always at the start of the buffer */ + int used = 0; + + if (buflen < sizeof(struct cscfg_file_header)) + return -EINVAL; + + cscfg_extract_u32(hdr->magic_version); + if (hdr->magic_version != CSCFG_FILE_MAGIC_VERSION) + return -EINVAL; + + cscfg_extract_u16(hdr->length); + if (hdr->length > buflen) + return -EINVAL; + + cscfg_extract_u16(hdr->nr_configs); + cscfg_extract_u16(hdr->nr_features); + + *buf_used = used; + return 0; +} + +static int cscfg_file_read_elem_hdr(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_file_elem_header *elem_hdr) +{ + int used = *buf_used; + + if ((buflen - used) < (sizeof(u16) + sizeof(u8))) + return -EINVAL; + + /* read length and check enough buffer remains for this element */ + elem_hdr->elem_length = *(u16 *)(buffer + used); + if ((buflen - used) < elem_hdr->elem_length) + return -EINVAL; + /* don't use extract fn as we update used _after_ the comparison */ + used += sizeof(u16); + + /* read type and validate */ + cscfg_extract_u8(elem_hdr->elem_type); + if ((elem_hdr->elem_type < CSCFG_FILE_ELEM_TYPE_FEAT) || + (elem_hdr->elem_type > CSCFG_FILE_ELEM_TYPE_CFG)) + return -EINVAL; + + *buf_used = used; + return 0; +} + +static int cscfg_file_read_elem_str(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_file_elem_str *elem_str) +{ + int used = *buf_used; + + if ((buflen - used) < sizeof(u16)) + return -EINVAL; + + cscfg_extract_u16(elem_str->str_len); + + if ((buflen - used) < elem_str->str_len) + return -EINVAL; + + /* check for 0 termination */ + if (buffer[used + (elem_str->str_len - 1)] != 0) + return -EINVAL; + + elem_str->str = kstrdup((char *)(buffer + used), GFP_KERNEL); + used += elem_str->str_len; + + *buf_used = used; + return 0; +} + +static int cscfg_file_alloc_desc_arrays(struct cscfg_fs_load_descs *desc_arrays, + int nr_features, int nr_configs) +{ + /* arrays are 0 terminated - nr_configs & nr_features elements */ + desc_arrays->config_descs = kcalloc(nr_configs + 1, sizeof(struct cscfg_config_desc *), + GFP_KERNEL); + if (!desc_arrays->config_descs) + return -ENOMEM; + desc_arrays->feat_descs = kcalloc(nr_features + 1, sizeof(struct cscfg_feature_desc *), + GFP_KERNEL); + if (!desc_arrays->feat_descs) + return -ENOMEM; + return 0; +} + +/* free up the data allocated to a config desc */ +static void cscfg_file_free_config_desc(struct cscfg_config_desc *config_desc) +{ + int i; + + if (!config_desc) + return; + + /* free presets */ + kfree(config_desc->presets); + + /* free feat ref strings */ + if (config_desc->nr_feat_refs) { + /* each string */ + for (i = 0; i < config_desc->nr_feat_refs; i++) + kfree(config_desc->feat_ref_names[i]); + + /* and the char * array */ + kfree(config_desc->feat_ref_names); + } + + /* next the strings */ + kfree(config_desc->name); + kfree(config_desc->description); + + /* finally the struct itself */ + kfree(config_desc); +} + +static int cscfg_file_read_elem_config(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_fs_load_descs *desc_arrays, + const int cfg_index) +{ + struct cscfg_file_elem_header elem_hdr; + struct cscfg_file_elem_str elem_str; + struct cscfg_config_desc *config_desc; + int used = *buf_used, nr_preset_vals, nr_preset_bytes, i; + int err = 0; + u64 *presets; + + /* + * read the header - if not config, then don't update buf_used + * pointer on return + */ + err = cscfg_file_read_elem_hdr(buffer, buflen, &used, &elem_hdr); + if (err) + return err; + if (elem_hdr.elem_type != CSCFG_FILE_ELEM_TYPE_CFG) + return 0; + + /* we have a config - allocate the descriptor */ + config_desc = kzalloc(sizeof(struct cscfg_config_desc), GFP_KERNEL); + if (!config_desc) + return -ENOMEM; + + /* read the name string */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + config_desc->name = elem_str.str; + + /* read the description string */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + config_desc->description = elem_str.str; + + /* read in some values */ + if ((buflen - used) < sizeof(u64)) + return -EINVAL; + cscfg_extract_u16(config_desc->nr_presets); + cscfg_extract_u32(config_desc->nr_total_params); + cscfg_extract_u16(config_desc->nr_feat_refs); + + /* read the array of 64bit presets if present */ + nr_preset_vals = config_desc->nr_total_params * config_desc->nr_presets; + if (nr_preset_vals) { + presets = kcalloc(nr_preset_vals, sizeof(u64), GFP_KERNEL); + if (!presets) + return -ENOMEM; + + nr_preset_bytes = sizeof(u64) * nr_preset_vals; + if ((buflen - used) < nr_preset_bytes) + return -EINVAL; + + memcpy(presets, (buffer + used), nr_preset_bytes); + config_desc->presets = presets; + used += nr_preset_bytes; + } + + /* read the array of feature names referenced by the config */ + if (config_desc->nr_feat_refs) { + config_desc->feat_ref_names = kcalloc(config_desc->nr_feat_refs, + sizeof(char *), GFP_KERNEL); + if (!config_desc->feat_ref_names) + return -ENOMEM; + + for (i = 0; i < config_desc->nr_feat_refs; i++) { + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + config_desc->feat_ref_names[i] = elem_str.str; + } + } + + desc_arrays->config_descs[cfg_index] = config_desc; + *buf_used = used; + return 0; +} + +/* + * Read a config name - if there is a config at this position. + * + * Reads the element header at the current position. + * If it is a configuration header (type = CSCFG_FILE_ELEM_TYPE_CFG), + * then continue and read the configuration name into @elem_str and update the + * @buf_used pointers. + * + * Otherwise return 0, without updating the used pointers. + */ +static int cscfg_file_read_elem_config_name(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_file_elem_str *elem_str) +{ + struct cscfg_file_elem_header elem_hdr; + int used = *buf_used; + int err; + + elem_str->str_len = 0; + /* + * read the header - if not config, then don't update buf_used + * pointer on return + */ + err = cscfg_file_read_elem_hdr(buffer, buflen, &used, &elem_hdr); + if (err) + return err; + if (elem_hdr.elem_type != CSCFG_FILE_ELEM_TYPE_CFG) + return 0; + + /* read the name string */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, elem_str); + if (err) + return err; + *buf_used = used; + + return 0; +} + +static int cscfg_file_read_elem_param(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_parameter_desc *param_desc) +{ + struct cscfg_file_elem_str elem_str; + int err = 0, used = *buf_used; + + /* parameter name */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + param_desc->name = elem_str.str; + + /* parameter value */ + if ((buflen - used) < sizeof(u64)) + return -EINVAL; + cscfg_extract_u64(param_desc->value); + + *buf_used = used; + return err; +} + +static void cscfg_file_free_feat_desc(struct cscfg_feature_desc *feat_desc) +{ + if (!feat_desc) + return; + + /* free up the register descriptor array */ + kfree(feat_desc->regs_desc); + + /* free up the parameters array */ + kfree(feat_desc->params_desc); + + /* name and description strings */ + kfree(feat_desc->name); + kfree(feat_desc->description); + + /* finally the struct itself */ + kfree(feat_desc); +} + +static int cscfg_file_read_elem_feature(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_fs_load_descs *desc_arrays, + const int feat_idx) +{ + struct cscfg_file_elem_header elem_hdr; + struct cscfg_file_elem_str elem_str; + struct cscfg_feature_desc *feat_desc; + struct cscfg_regval_desc *p_reg_desc; + int used = *buf_used, err, i, nr_regs_bytes; + u32 val32; + + /* allocate the feature descriptor object */ + feat_desc = kzalloc(sizeof(struct cscfg_feature_desc), GFP_KERNEL); + if (!feat_desc) + return -ENOMEM; + + /* read and check the element header */ + err = cscfg_file_read_elem_hdr(buffer, buflen, &used, &elem_hdr); + if (err) + return err; + + if (elem_hdr.elem_type != CSCFG_FILE_ELEM_TYPE_FEAT) + return -EINVAL; + + /* read the feature name */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + feat_desc->name = elem_str.str; + + /* read the description string */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, &elem_str); + if (err) + return err; + feat_desc->description = elem_str.str; + + /* + * read in some values + * [u32 value: match_flags] + * [u16 value: nr_regs] - number of registers. + * [u16 value: nr_params] - number of parameters. + */ + cscfg_extract_u32(feat_desc->match_flags); + cscfg_extract_u16(feat_desc->nr_regs); + cscfg_extract_u16(feat_desc->nr_params); + + /* register descriptors - 32 bit + 64 bit value */ + if (feat_desc->nr_regs) { + nr_regs_bytes = ((sizeof(u32) + sizeof(u64)) * feat_desc->nr_regs); + if ((buflen - used) < nr_regs_bytes) + return -EINVAL; + feat_desc->regs_desc = kcalloc(feat_desc->nr_regs, + sizeof(struct cscfg_regval_desc), GFP_KERNEL); + if (!feat_desc->regs_desc) + return -ENOMEM; + + for (i = 0; i < feat_desc->nr_regs; i++) { + cscfg_extract_u32(val32); + p_reg_desc = (struct cscfg_regval_desc *)&feat_desc->regs_desc[i]; + CSCFG_FILE_U32_TO_REG_DESC_INFO(val32, p_reg_desc); + cscfg_extract_u64(feat_desc->regs_desc[i].val64); + } + } + + /* parameter descriptors - string + 64 bit value */ + if (feat_desc->nr_params) { + feat_desc->params_desc = kcalloc(feat_desc->nr_params, + sizeof(struct cscfg_parameter_desc), GFP_KERNEL); + if (!feat_desc->params_desc) + return -ENOMEM; + for (i = 0; i < feat_desc->nr_params; i++) { + err = cscfg_file_read_elem_param(buffer, buflen, &used, + &feat_desc->params_desc[i]); + if (err) + return err; + } + } + + desc_arrays->feat_descs[feat_idx] = feat_desc; + *buf_used = used; + return 0; +} + +/* + * Read a feature name. + * + * Check the element header to ensure that a feature (type = CSCFG_FILE_ELEM_TYPE_FEAT) + * is at this position and read the following string & update @buf_used. + * + * If not a feature then return -EINVAL. + */ +static int cscfg_file_read_elem_feat_name(const u8 *buffer, const int buflen, int *buf_used, + struct cscfg_file_elem_str *elem_str) +{ + struct cscfg_file_elem_header elem_hdr; + int used = *buf_used; + int err; + + elem_str->str_len = 0; + /* + * read the header - if not feature, then don't update buf_used + * pointer on return + */ + err = cscfg_file_read_elem_hdr(buffer, buflen, &used, &elem_hdr); + if (err) + return err; + if (elem_hdr.elem_type != CSCFG_FILE_ELEM_TYPE_FEAT) + return -EINVAL; + + /* read the feature name */ + err = cscfg_file_read_elem_str(buffer, buflen, &used, elem_str); + if (err) + return err; + *buf_used = used; + + return 0; +} + +/* + * Read a buffer and create the configuration and feature + * descriptors to load into the cscfg system + */ +int cscfg_file_read_buffer(const u8 *buffer, const int buflen, + struct cscfg_fs_load_descs *desc_arrays) +{ + struct cscfg_file_header hdr; + int used = 0, err, i; + + /* read in the file header */ + err = cscfg_file_read_hdr(buffer, buflen, &used, &hdr); + if (err) + return err; + + /* allocate the memory for the descriptor pointer arrays */ + err = cscfg_file_alloc_desc_arrays(desc_arrays, hdr.nr_features, hdr.nr_configs); + if (err) + return err; + + /* read elements */ + + /* first elements are configurations */ + for (i = 0; i < hdr.nr_configs; i++) { + err = cscfg_file_read_elem_config(buffer, buflen, &used, desc_arrays, i); + if (err) + return err; + } + + /* now read and populate all the feature descriptors */ + for (i = 0; i < hdr.nr_features; i++) { + err = cscfg_file_read_elem_feature(buffer, buflen, &used, desc_arrays, i); + if (err) + return err; + } + return 0; +} + +int cscfg_file_read_buffer_first_name(const u8 *buffer, const int buflen, + const char **name) +{ + struct cscfg_file_header hdr; + struct cscfg_file_elem_str elem_str; + int used = 0, err = 0; + + *name = NULL; + + /* read in the file header */ + err = cscfg_file_read_hdr(buffer, buflen, &used, &hdr); + if (err) + return err; + + err = cscfg_file_read_elem_config_name(buffer, buflen, &used, &elem_str); + if (err) + return err; + + /* no config string - get first feature name */ + if (!elem_str.str_len) { + err = cscfg_file_read_elem_feat_name(buffer, buflen, &used, &elem_str); + if (err) + return err; + } + if (elem_str.str_len) + *name = elem_str.str; + return err; +} + +/* + * Need to free up the dynamically allocated descriptor arrays on unload + * as the memory used could be significant if many configurations are loaded + * and unloaded while the machine is operational. + * + * This frees up all the memory allocated by this file during the load process. + */ +void cscfg_file_free_load_descs(struct cscfg_fs_load_descs *desc_arrays) +{ + int i = 0; + + if (!desc_arrays) + return; + + /* free up each of the config descriptors */ + while (desc_arrays->config_descs[i]) { + cscfg_file_free_config_desc(desc_arrays->config_descs[i]); + i++; + } + + /* free up each of the feature descriptors */ + i = 0; + while (desc_arrays->feat_descs[i]) { + cscfg_file_free_feat_desc(desc_arrays->feat_descs[i]); + i++; + } + + /* finally free up the load descs pointer arrays */ + kfree(desc_arrays->config_descs); + kfree(desc_arrays->feat_descs); +} diff --git a/drivers/hwtracing/coresight/coresight-config-file.h b/drivers/hwtracing/coresight/coresight-config-file.h new file mode 100644 index 000000000000..6e8d259dfaaa --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-config-file.h @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2020-2022 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#ifndef _CORESIGHT_CORESIGHT_CONFIG_FILE_H +#define _CORESIGHT_CORESIGHT_CONFIG_FILE_H + +#include <linux/sizes.h> + +#include "coresight-config.h" + +/* + * Structures to represent configuration descriptors in a memory buffer + * to serialise to and from files + * + * File structure - for loading configuration(s) + feature(s) + * from configfs. + * + * [cscfg_file_header] - mandatory + * [CONFIG_ELEM] * [cscfg_file_header.nr_configs] - optional. + * [FEATURE_ELEM] * [cscfg_file_header.nr_features] - optional. + * + * File valid if it has both config(s) and feature(s), only config(s) + * or only feature(s). + * Invalid file if no config or features. + * + * File structure for [CONFIG_ELEM]: + * + * [cscfg_file_elem_header] - header length value to end of feature strings. + * [cscfg_file_elem_str] - name of the configuration + * [cscfg_file_elem_str] - description of configuration + * [u16 value - nr_presets] - number of sets of presets supplied + * [u32 value - nr_total_params] - total of all params in referenced features + * [u16 value - nr_feat_refs] - number of features selected by this configuration + * [u64 values] * (nr_presets * nr_total_params) + * [cscfg_file_elem_str] * nr_feat_refs - names of features selected by configuration. + * + * A configuration must reference at least one feature. + * Referenced features may be in this file, or have been loaded previously. + * + * File structure for a [FEATURE_ELEM] + * + * [cscfg_file_elem_header] - header length is total bytes to end of param structures. + * [cscfg_file_elem_str] - feature name. + * [cscfg_file_elem_str] - feature description. + * [u32 value: match_flags] + * [u16 value: nr_regs] - number of registers. + * [u16 value: nr_params] - number of parameters. + * [cscfg_regval_desc struct] * nr_regs + * [PARAM_ELEM] * nr_params + * + * File structure for [PARAM_ELEM] + * + * [cscfg_file_elem_str] - parameter name. + * [u64 value: param_value] - initial value. + */ + +/* major element types - configurations and features */ + +#define CSCFG_FILE_ELEM_TYPE_FEAT 0x1 +#define CSCFG_FILE_ELEM_TYPE_CFG 0x2 + +#define CSCFG_FILE_MAGIC_VERSION 0xC5CF0001 + +#define CSCFG_FILE_U32_TO_REG_DESC_INFO(val32, p_desc) \ + { \ + p_desc->type = (val32 >> 24) & 0xFF; \ + p_desc->offset = (val32 >> 12) & 0xFFF; \ + p_desc->hw_info = val32 & 0xFFF; \ + } + +#define CSCFG_FILE_REG_DESC_INFO_TO_U32(val32, p_desc) \ + { \ + val32 = p_desc->hw_info & 0xFFF; \ + val32 |= ((p_desc->offset & 0xFFF) << 12); \ + val32 |= ((p_desc->type & 0xFF) << 24); \ + } + +/* + * Binary attributes in configfs need a max size, as an internal buffer is declared, + * and will not be exceeded to prevent kernel OOM errors / attacks. + * + * Use a value that will reasonably cover all the usable & programmable registers in + * an ETM, the most complex device we have. + */ +#define CSCFG_FILE_MAXSIZE SZ_16K + +/* limit string sizes - used for descriptions and names. */ +#define CSCFG_FILE_STR_MAXSIZE SZ_1K + +/** + * file header. + * + * @magic_version: magic number / version for file/buffer format. + * @length : total length of all data in the buffer. + * @nr_configs : total number of configs in the buffer. + * @nr_features : total number of features in the buffer. + */ +struct cscfg_file_header { + u32 magic_version; + u16 length; + u16 nr_configs; + u16 nr_features; +}; + +/** + * element header + * + * @elem_length: total length of this element + * @elem_type : type of this element - one of CSCFG_FILE_ELEM_TYPE.. defines. + */ +struct cscfg_file_elem_header { + u16 elem_length; + u8 elem_type; +}; + +/** + * string file element. + * + * @str_len: length of string buffer including 0 terminator + * @str : string buffer - 0 terminated. + */ +struct cscfg_file_elem_str { + u16 str_len; + char *str; +}; + +/* kernel configfs needs to read the incoming file buffers to load. */ +int cscfg_file_read_buffer(const u8 *buffer, const int buflen, + struct cscfg_fs_load_descs *desc_arrays); +/* to unload we just need the first name - config or first feature */ +int cscfg_file_read_buffer_first_name(const u8 *buffer, const int buflen, + const char **name); +/* on unload we need to free up memory allocated on read */ +void cscfg_file_free_load_descs(struct cscfg_fs_load_descs *desc_arrays); + +#endif /* _CORESIGHT_CORESIGHT_CONFIG_FILE_H */ diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 6ba013975741..ad212954f99e 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -85,6 +85,21 @@ struct cscfg_regval_desc { }; };
+/** + * Dynamically loaded descriptor arrays loaded via configfs. + * + * For builtin or module loaded configurations / features these are + * statically defined at compile time. For configfs we create the arrays + * dynamically so need a structure to handle this. + * + * @config_descs: array of config descriptor pointers. + * @feat_descs: array of feature descriptor pointers. + */ +struct cscfg_fs_load_descs { + struct cscfg_config_desc **config_descs; + struct cscfg_feature_desc **feat_descs; +}; + /** * Device feature descriptor - combination of registers and parameters to * program a device to implement a specific complex function. diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 66e2db890d82..d0c9543850c0 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -79,6 +79,7 @@ struct cscfg_registered_csdev { enum cscfg_load_owner_type { CSCFG_OWNER_PRELOAD, CSCFG_OWNER_MODULE, + CSCFG_OWNER_CONFIGFS, };
/**