From 049d919168458ac54e7fad27cd156a958b042d2f Mon Sep 17 00:00:00 2001 From: Joakim Zhang Date: Tue, 25 Feb 2020 20:56:43 +0800 Subject: [PATCH 1/3] drivers/perf: fsl_imx8_ddr: Correct the CLEAR bit definition When disabling a counter from ddr_perf_event_stop(), the counter value is reset to 0 at the same time. Preserve the counter value by performing a read-modify-write of the PMU register and clearing only the enable bit. Signed-off-by: Joakim Zhang Signed-off-by: Will Deacon --- drivers/perf/fsl_imx8_ddr_perf.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c index 95dca2cb5265..90884d14f95f 100644 --- a/drivers/perf/fsl_imx8_ddr_perf.c +++ b/drivers/perf/fsl_imx8_ddr_perf.c @@ -388,9 +388,10 @@ static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config, if (enable) { /* - * must disable first, then enable again - * otherwise, cycle counter will not work - * if previous state is enabled. + * cycle counter is special which should firstly write 0 then + * write 1 into CLEAR bit to clear it. Other counters only + * need write 0 into CLEAR bit and it turns out to be 1 by + * hardware. Below enable flow is harmless for all counters. */ writel(0, pmu->base + reg); val = CNTL_EN | CNTL_CLEAR; @@ -398,7 +399,8 @@ static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config, writel(val, pmu->base + reg); } else { /* Disable counter */ - writel(0, pmu->base + reg); + val = readl_relaxed(pmu->base + reg) & CNTL_EN_MASK; + writel(val, pmu->base + reg); } } From 3ba52ad55b533760a1f65836aa0ec9d35e36bb4f Mon Sep 17 00:00:00 2001 From: luanshi Date: Wed, 26 Feb 2020 13:45:10 +0800 Subject: [PATCH 2/3] drivers/perf: arm_pmu_acpi: Fix incorrect checking of gicc pointer Fix bogus NULL checks on the return value of acpi_cpu_get_madt_gicc() by checking for a 0 'gicc->performance_interrupt' value instead. Signed-off-by: Liguang Zhang Signed-off-by: Will Deacon --- drivers/perf/arm_pmu_acpi.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c index acce8781c456..f5c7a845cd7b 100644 --- a/drivers/perf/arm_pmu_acpi.c +++ b/drivers/perf/arm_pmu_acpi.c @@ -24,8 +24,6 @@ static int arm_pmu_acpi_register_irq(int cpu) int gsi, trigger; gicc = acpi_cpu_get_madt_gicc(cpu); - if (WARN_ON(!gicc)) - return -EINVAL; gsi = gicc->performance_interrupt; @@ -64,11 +62,10 @@ static void arm_pmu_acpi_unregister_irq(int cpu) int gsi; gicc = acpi_cpu_get_madt_gicc(cpu); - if (!gicc) - return; gsi = gicc->performance_interrupt; - acpi_unregister_gsi(gsi); + if (gsi) + acpi_unregister_gsi(gsi); } #if IS_ENABLED(CONFIG_ARM_SPE_PMU) From 9abd515a6e4a5c58c6eb4d04110430325eb5f5ac Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Thu, 27 Feb 2020 09:34:47 +0100 Subject: [PATCH 3/3] arm64: context: Fix ASID limit in boot messages Since commit f88f42f853a8 ("arm64: context: Free up kernel ASIDs if KPTI is not in use"), the NUM_USER_ASIDS macro doesn't correspond to the effective number of ASIDs when KPTI is enabled. Get an accurate number of available ASIDs in an arch_initcall, once we've discovered all CPUs' capabilities and know if we still need to halve the ASID space for KPTI. Fixes: f88f42f853a8 ("arm64: context: Free up kernel ASIDs if KPTI is not in use") Reviewed-by: Vladimir Murzin Signed-off-by: Jean-Philippe Brucker Signed-off-by: Will Deacon --- arch/arm64/mm/context.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index 8ef73e89d514..d89bb22589f6 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -260,14 +260,26 @@ asmlinkage void post_ttbr_update_workaround(void) CONFIG_CAVIUM_ERRATUM_27456)); } -static int asids_init(void) +static int asids_update_limit(void) { - asid_bits = get_cpu_asid_bits(); + unsigned long num_available_asids = NUM_USER_ASIDS; + + if (arm64_kernel_unmapped_at_el0()) + num_available_asids /= 2; /* * Expect allocation after rollover to fail if we don't have at least * one more ASID than CPUs. ASID #0 is reserved for init_mm. */ - WARN_ON(NUM_USER_ASIDS - 1 <= num_possible_cpus()); + WARN_ON(num_available_asids - 1 <= num_possible_cpus()); + pr_info("ASID allocator initialised with %lu entries\n", + num_available_asids); + return 0; +} +arch_initcall(asids_update_limit); + +static int asids_init(void) +{ + asid_bits = get_cpu_asid_bits(); atomic64_set(&asid_generation, ASID_FIRST_VERSION); asid_map = kcalloc(BITS_TO_LONGS(NUM_USER_ASIDS), sizeof(*asid_map), GFP_KERNEL); @@ -282,8 +294,6 @@ static int asids_init(void) */ if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) set_kpti_asid_bits(); - - pr_info("ASID allocator initialised with %lu entries\n", NUM_USER_ASIDS); return 0; } early_initcall(asids_init);