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@arm.com Cc: Will Deacon will@kernel.org Cc: Mark Rutland mark.rutland@arm.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com --- 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 bd68e1b7f29f..4d537d56eb84 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 72454bef2a70..845683ca7c64 100644 --- a/drivers/perf/arm_pmu_acpi.c +++ b/drivers/perf/arm_pmu_acpi.c @@ -164,6 +164,40 @@ 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; @@ -399,6 +433,7 @@ 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 a0801f68762b..143fbc10ecfe 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__ */