Commit fb6fb072 authored Oct 28, 2023 by Anshuman Khandual Committed by Junhao He Oct 28, 2023

coresight: trbe: Add a representative coresight_platform_data for TRBE

maillist inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8BOB3
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux.git/commit/?h=next&id=4817af577b82adedcabbb4463e77ab2afe6d37b0



--------------------------------

TRBE coresight devices do not need regular connections information, as the
paths get built between all percpu source and their respective percpu sink
devices. Please refer 'commit 2cd87a7b ("coresight: core: Add support
for dedicated percpu sinks")' which added support for percpu sink devices.

coresight_register() expect device connections via the platform_data. TRBE
devices do not have any graph connections and thus is empty. With upcoming
ACPI support for TRBE, we do not get a real acpi_device and thus
coresight_get_platform_dat() will end up in failures. Hence this allocates
a zeroed coresight_platform_data structure and assigns that back into the
device.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230829135405.1159449-2-anshuman.khandual@arm.com


Signed-off-by: Junhao He <hejunhao3@huawei.com>

parent eb6153f2

drivers/hwtracing/coresight/coresight-trbe.c

+12 −2

Original line number	Diff line number	Diff line
		@@ -947,8 +947,18 @@ static void arm_trbe_register_coresight_cpu(struct trbe_drvdata *drvdata, int cp
		desc.name = devm_kasprintf(dev, GFP_KERNEL, "trbe%d", cpu);
		if (!desc.name)
		goto cpu_clear;

		desc.pdata = coresight_get_platform_data(dev);
		/*
		* TRBE coresight devices do not need regular connections
		* information, as the paths get built between all percpu
		* source and their respective percpu sink devices. Though
		* coresight_register() expect device connections via the
		* platform_data, which TRBE devices do not have. As they
		* are not real ACPI devices, coresight_get_platform_data()
		* ends up failing. Instead let's allocate a dummy zeroed
		* coresight_platform_data structure and assign that back
		* into the device for that purpose.
		*/
		desc.pdata = devm_kzalloc(dev, sizeof(*desc.pdata), GFP_KERNEL);
		if (IS_ERR(desc.pdata))
		goto cpu_clear;