Re: [PATCH 6.5 006/191] arm_pmu: acpi: Add a representative platform device for TRBE

[Thorsten Leemhuis]

On 16.10.23 10:39, Greg Kroah-Hartman wrote:
> 6.5-stable review patch.  If anyone has any objections, please let me know.
> 
> ------------------
> 
> From: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> 
> [ Upstream commit 1aa3d0274a4aac338ee45a3dfc3b17c944bcc2bc ]
> 
> ACPI TRBE does not have a HID for identification which could create and add
> a platform device into the platform bus. Also without a platform device, it
> cannot be probed and bound to a platform driver.
> 
> This creates a dummy platform device for TRBE after ascertaining that ACPI
> provides required interrupts uniformly across all cpus on the system. This
> device gets created inside drivers/perf/arm_pmu_acpi.c to accommodate TRBE
> being built as a module.
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> Link: https://lore.kernel.org/r/20230817055405.249630-3-anshuman.khandual@xxxxxxx
> Signed-off-by: Will Deacon <will@xxxxxxxxxx>
> Stable-dep-of: 4785aa802853 ("cpuidle, ACPI: Evaluate LPI arch_flags for broadcast timer")
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

Got a compiler error when using Fedora's stable kernel config and
compiling 6.5.8-rc1 for ARM64; not totally sure, but from the error msg
I suspect it's caused by the change quoted above.

"""
+ /usr/bin/make -s 'HOSTCFLAGS=-O2  -fexceptions -g
-grecord-gcc-switches -pipe -Wall -Werror=format-security
-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS
-specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong
-specs=/usr/lib/rpm/redhat/redhat-annobin-cc1
-mbranch-protection=standard -fasynchronous-unwind-tables
-fstack-clash-protection' 'HOSTLDFLAGS=-Wl,-z,relro -Wl,--as-needed
-Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld
-specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -Wl,--build-id=sha1
-specs=/usr/lib/rpm/redhat/redhat-package-notes' ARCH=arm64 'KCFLAGS= '
WITH_GCOV=0 -j4 vmlinuz.efi
drivers/perf/arm_pmu_acpi.c: In function 'arm_trbe_acpi_register_device':
drivers/perf/arm_pmu_acpi.c:164:19: error: implicit declaration of
function 'arm_acpi_register_pmu_device'; did you mean
'arm_spe_acpi_register_device'? [-Werror=implicit-function-declaration]
  164 |         int ret = arm_acpi_register_pmu_device(&trbe_dev,
ACPI_MADT_GICC_TRBE,
      |                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                   arm_spe_acpi_register_device
cc1: some warnings being treated as errors
make[4]: *** [scripts/Makefile.build:243: drivers/perf/arm_pmu_acpi.o]
Error 1
make[4]: *** Waiting for unfinished jobs....
make[3]: *** [scripts/Makefile.build:480: drivers/perf] Error 2
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [scripts/Makefile.build:480: drivers] Error 2
make[1]: ***
[/builddir/build/BUILD/kernel-6.5.8-rc1/linux-6.5.8-0.rc1.150.vanilla.fc37.aarch64/Makefile:2036:
.] Error 2
make: *** [Makefile:236: __sub-make] Error 2
"""

Full build log:
https://copr-be.cloud.fedoraproject.org/results/@kernel-vanilla/stable-rc/fedora-37-aarch64/06529454-stablerc-stablerc-releases/builder-live.log.gz

Ciao, Thorsten

> ---
>  arch/arm64/include/asm/acpi.h |  3 +++
>  drivers/perf/arm_pmu_acpi.c   | 35 +++++++++++++++++++++++++++++++++++
>  include/linux/perf/arm_pmu.h  |  1 +
>  3 files changed, 39 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
> index bd68e1b7f29f3..4d537d56eb847 100644
> --- a/arch/arm64/include/asm/acpi.h
> +++ b/arch/arm64/include/asm/acpi.h
> @@ -42,6 +42,9 @@
>  #define ACPI_MADT_GICC_SPE  (offsetof(struct acpi_madt_generic_interrupt, \
>  	spe_interrupt) + sizeof(u16))
>  
> +#define ACPI_MADT_GICC_TRBE  (offsetof(struct acpi_madt_generic_interrupt, \
> +	trbe_interrupt) + sizeof(u16))
> +
>  /* Basic configuration for ACPI */
>  #ifdef	CONFIG_ACPI
>  pgprot_t __acpi_get_mem_attribute(phys_addr_t addr);
> diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c
> index 90815ad762ebc..8baeeb369118e 100644
> --- a/drivers/perf/arm_pmu_acpi.c
> +++ b/drivers/perf/arm_pmu_acpi.c
> @@ -139,6 +139,40 @@ static inline void arm_spe_acpi_register_device(void)
>  }
>  #endif /* CONFIG_ARM_SPE_PMU */
>  
> +#if IS_ENABLED(CONFIG_CORESIGHT_TRBE)
> +static struct resource trbe_resources[] = {
> +	{
> +		/* irq */
> +		.flags          = IORESOURCE_IRQ,
> +	}
> +};
> +
> +static struct platform_device trbe_dev = {
> +	.name = ARMV8_TRBE_PDEV_NAME,
> +	.id = -1,
> +	.resource = trbe_resources,
> +	.num_resources = ARRAY_SIZE(trbe_resources)
> +};
> +
> +static u16 arm_trbe_parse_gsi(struct acpi_madt_generic_interrupt *gicc)
> +{
> +	return gicc->trbe_interrupt;
> +}
> +
> +static void arm_trbe_acpi_register_device(void)
> +{
> +	int ret = arm_acpi_register_pmu_device(&trbe_dev, ACPI_MADT_GICC_TRBE,
> +					       arm_trbe_parse_gsi);
> +	if (ret)
> +		pr_warn("ACPI: TRBE: Unable to register device\n");
> +}
> +#else
> +static inline void arm_trbe_acpi_register_device(void)
> +{
> +
> +}
> +#endif /* CONFIG_CORESIGHT_TRBE */
> +
>  static int arm_pmu_acpi_parse_irqs(void)
>  {
>  	int irq, cpu, irq_cpu, err;
> @@ -374,6 +408,7 @@ static int arm_pmu_acpi_init(void)
>  		return 0;
>  
>  	arm_spe_acpi_register_device();
> +	arm_trbe_acpi_register_device();
>  
>  	return 0;
>  }
> diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
> index a0801f68762bf..143fbc10ecfe0 100644
> --- a/include/linux/perf/arm_pmu.h
> +++ b/include/linux/perf/arm_pmu.h
> @@ -187,5 +187,6 @@ void armpmu_free_irq(int irq, int cpu);
>  #endif /* CONFIG_ARM_PMU */
>  
>  #define ARMV8_SPE_PDEV_NAME "arm,spe-v1"
> +#define ARMV8_TRBE_PDEV_NAME "arm,trbe"
>  
>  #endif /* __ARM_PMU_H__ */