Re: [PATCH v8 7/7] coresight: config: Add preloaded configuration

On 31/05/2024 05:27, Linu Cherian wrote:

Add a preloaded configuration for generating external trigger on address match. This can be used by CTI and ETR blocks to stop trace capture on kernel panic.

Kernel address for "panic" function is used as the default trigger address.

This new configuration is available as, /sys/kernel/config/cs-syscfg/configurations/panicstop

Reviewed-by: James Clark james.clark@arm.com

Signed-off-by: Linu Cherian lcherian@marvell.com

drivers/hwtracing/coresight/Makefile | 2 +- .../coresight/coresight-cfg-preload.c | 2 + .../coresight/coresight-cfg-preload.h | 2 + .../hwtracing/coresight/coresight-cfg-pstop.c | 83 +++++++++++++++++++ 4 files changed, 88 insertions(+), 1 deletion(-) create mode 100644 drivers/hwtracing/coresight/coresight-cfg-pstop.c

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index 4ba478211b31..46ce7f39d05f 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -25,7 +25,7 @@ subdir-ccflags-y += $(condflags) obj-$(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-cfg-pstop.o \
  

  coresight-syscfg-configfs.o coresight-trace-id.o

obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \ diff --git a/drivers/hwtracing/coresight/coresight-cfg-preload.c b/drivers/hwtracing/coresight/coresight-cfg-preload.c index e237a4edfa09..4980e68483c5 100644 --- a/drivers/hwtracing/coresight/coresight-cfg-preload.c +++ b/drivers/hwtracing/coresight/coresight-cfg-preload.c @@ -13,6 +13,7 @@ static struct cscfg_feature_desc *preload_feats[] = { #if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) &strobe_etm4x,

• &gen_etrig_etm4x,

#endif NULL }; @@ -20,6 +21,7 @@ static struct cscfg_feature_desc *preload_feats[] = { static struct cscfg_config_desc *preload_cfgs[] = { #if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) &afdo_etm4x,

• &pstop_etm4x,

#endif NULL }; diff --git a/drivers/hwtracing/coresight/coresight-cfg-preload.h b/drivers/hwtracing/coresight/coresight-cfg-preload.h index 21299e175477..291ba530a6a5 100644 --- a/drivers/hwtracing/coresight/coresight-cfg-preload.h +++ b/drivers/hwtracing/coresight/coresight-cfg-preload.h @@ -10,4 +10,6 @@ #if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) extern struct cscfg_feature_desc strobe_etm4x; extern struct cscfg_config_desc afdo_etm4x; +extern struct cscfg_feature_desc gen_etrig_etm4x; +extern struct cscfg_config_desc pstop_etm4x; #endif diff --git a/drivers/hwtracing/coresight/coresight-cfg-pstop.c b/drivers/hwtracing/coresight/coresight-cfg-pstop.c new file mode 100644 index 000000000000..c2bfbd07bfaf --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-cfg-pstop.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • Copyright(C) 2023 Marvell.
• • Based on coresight-cfg-afdo.c
• */

+#include "coresight-config.h"

+/* ETMv4 includes and features */ +#if IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) +#include "coresight-etm4x-cfg.h"

+/* preload configurations and features */

+/* preload in features for ETMv4 */

+/* panic_stop feature */ +static struct cscfg_parameter_desc gen_etrig_params[] = {

• {

• .name = "address",
  

• .value = (u64)panic,
  

• },

+};

+static struct cscfg_regval_desc gen_etrig_regs[] = {

• /* resource selector */
• {

• .type = CS_CFG_REG_TYPE_RESOURCE,
  

• .offset = TRCRSCTLRn(2),
  

• .hw_info = ETM4_CFG_RES_SEL,
  

• .val32 = 0x40001,
  

• },
• /* single address comparator */
• {

• .type = CS_CFG_REG_TYPE_RESOURCE | CS_CFG_REG_TYPE_VAL_64BIT |
  

• 	CS_CFG_REG_TYPE_VAL_PARAM,
  

• .offset =  TRCACVRn(0),
  

• .val32 = 0x0,
  

• },
• {

• .type = CS_CFG_REG_TYPE_RESOURCE,
  

• .offset = TRCACATRn(0),
  

• .val64 = 0xf00,
  

• },
• /* Driver external output[0] with comparator out */
• {

• .type = CS_CFG_REG_TYPE_RESOURCE,
  

• .offset = TRCEVENTCTL0R,
  

• .val32 = 0x2,
  

• },
• /* end of regs */

+};

+struct cscfg_feature_desc gen_etrig_etm4x = {

• .name = "gen_etrig",
• .description = "Generate external trigger on address match\n"

•        "parameter \'address\': address of kernel address\n",
  

• .match_flags = CS_CFG_MATCH_CLASS_SRC_ETM4,
• .nr_params = ARRAY_SIZE(gen_etrig_params),
• .params_desc = gen_etrig_params,
• .nr_regs = ARRAY_SIZE(gen_etrig_regs),
• .regs_desc = gen_etrig_regs,

+};

+/* create a panic stop configuration */

+/* the total number of parameters in used features */ +#define PSTOP_NR_PARAMS ARRAY_SIZE(gen_etrig_params)

+static const char *pstop_ref_names[] = {

• "gen_etrig",

+};

+struct cscfg_config_desc pstop_etm4x = {

• .name = "panicstop",
• .description = "Stop ETM on kernel panic\n",
• .nr_feat_refs = ARRAY_SIZE(pstop_ref_names),
• .feat_ref_names = pstop_ref_names,
• .nr_total_params = PSTOP_NR_PARAMS,

+};

+/* end of ETM4x configurations */ +#endif /* IS_ENABLED(CONFIG_CORESIGHT_SOURCE_ETM4X) */