From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 7C35B6BB41; Fri, 12 Jan 2024 14:04:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2176D1FB; Fri, 12 Jan 2024 06:05:16 -0800 (PST) Received: from [10.1.197.1] (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E21A93F5A1; Fri, 12 Jan 2024 06:04:26 -0800 (PST) Message-ID: <2c920dda-fdd3-436a-85cc-ead018f28ee4@arm.com> Date: Fri, 12 Jan 2024 14:04:25 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 7/7] coresight: config: Add preloaded configuration Content-Language: en-US To: Linu Cherian , mike.leach@linaro.org, james.clark@arm.com, leo.yan@linaro.org Cc: linux-arm-kernel@lists.infradead.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, devicetree@vger.kernel.org, sgoutham@marvell.com, gcherian@marvell.com References: <20240105055840.1977897-1-lcherian@marvell.com> <20240105055840.1977897-8-lcherian@marvell.com> From: Suzuki K Poulose In-Reply-To: <20240105055840.1977897-8-lcherian@marvell.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 05/01/2024 05:58, 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 to be > programmed as below. > > $cd /config/cs-syscfg/features/gen_etrig/params > $echo > address/value > > Signed-off-by: Linu Cherian > --- > Changelog from v5: > * No changes > > drivers/hwtracing/coresight/Makefile | 2 +- > .../coresight/coresight-cfg-preload.c | 2 + > .../coresight/coresight-cfg-preload.h | 2 + > .../hwtracing/coresight/coresight-cfg-pstop.c | 83 +++++++++++++++++++ > 4 files changed, 88 insertions(+), 1 deletion(-) > create mode 100644 drivers/hwtracing/coresight/coresight-cfg-pstop.c > > diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile > index 995d3b2c76df..68b15c8d9462 100644 > --- a/drivers/hwtracing/coresight/Makefile > +++ b/drivers/hwtracing/coresight/Makefile > @@ -5,7 +5,7 @@ > obj-$(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-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..037d6773fab8 > --- /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 = 0x0, > + }, > +}; > + > +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", Since this is actually generic, i.e., Stop trace on a Kernel address, we could rename this ? Or why don't we pre-populate the address of "panic" at load time. That way the user doesn't have to figure out the kernel address (e.g., if KASLR is enabled) Suzuki > + .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) */