From 6fe5c68ee6a1aae0ef291a56001e7888de547fa2 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Tue, 4 Jul 2023 17:50:34 +0200 Subject: irqchip/gic-v3: Workaround for GIC-700 erratum 2941627 GIC700 erratum 2941627 may cause GIC-700 missing SPIs wake requests when SPIs are deactivated while targeting a sleeping CPU - ie a CPU for which the redistributor: GICR_WAKER.ProcessorSleep == 1 This runtime situation can happen if an SPI that has been activated on a core is retargeted to a different core, it becomes pending and the target core subsequently enters a power state quiescing the respective redistributor. When this situation is hit, the de-activation carried out on the core that activated the SPI (through either ICC_EOIR1_EL1 or ICC_DIR_EL1 register writes) does not trigger a wake requests for the sleeping GIC redistributor even if the SPI is pending. Work around the erratum by de-activating the SPI using the redistributor GICD_ICACTIVER register if the runtime conditions require it (ie the IRQ was retargeted between activation and de-activation). Signed-off-by: Lorenzo Pieralisi Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230704155034.148262-1-lpieralisi@kernel.org --- drivers/irqchip/irq-gic-v3.c | 62 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 61 insertions(+), 1 deletion(-) (limited to 'drivers/irqchip/irq-gic-v3.c') diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 0c6c1af9a5b7..eedfa8e9f077 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -69,6 +69,8 @@ struct gic_chip_data { static void __iomem *t241_dist_base_alias[T241_CHIPS_MAX] __read_mostly; static DEFINE_STATIC_KEY_FALSE(gic_nvidia_t241_erratum); +static DEFINE_STATIC_KEY_FALSE(gic_arm64_2941627_erratum); + static struct gic_chip_data gic_data __read_mostly; static DEFINE_STATIC_KEY_TRUE(supports_deactivate_key); @@ -592,10 +594,39 @@ static void gic_irq_nmi_teardown(struct irq_data *d) gic_irq_set_prio(d, GICD_INT_DEF_PRI); } +static bool gic_arm64_erratum_2941627_needed(struct irq_data *d) +{ + enum gic_intid_range range; + + if (!static_branch_unlikely(&gic_arm64_2941627_erratum)) + return false; + + range = get_intid_range(d); + + /* + * The workaround is needed if the IRQ is an SPI and + * the target cpu is different from the one we are + * executing on. + */ + return (range == SPI_RANGE || range == ESPI_RANGE) && + !cpumask_test_cpu(raw_smp_processor_id(), + irq_data_get_effective_affinity_mask(d)); +} + static void gic_eoi_irq(struct irq_data *d) { write_gicreg(gic_irq(d), ICC_EOIR1_EL1); isb(); + + if (gic_arm64_erratum_2941627_needed(d)) { + /* + * Make sure the GIC stream deactivate packet + * issued by ICC_EOIR1_EL1 has completed before + * deactivating through GICD_IACTIVER. + */ + dsb(sy); + gic_poke_irq(d, GICD_ICACTIVER); + } } static void gic_eoimode1_eoi_irq(struct irq_data *d) @@ -606,7 +637,11 @@ static void gic_eoimode1_eoi_irq(struct irq_data *d) */ if (gic_irq(d) >= 8192 || irqd_is_forwarded_to_vcpu(d)) return; - gic_write_dir(gic_irq(d)); + + if (!gic_arm64_erratum_2941627_needed(d)) + gic_write_dir(gic_irq(d)); + else + gic_poke_irq(d, GICD_ICACTIVER); } static int gic_set_type(struct irq_data *d, unsigned int type) @@ -1816,6 +1851,12 @@ static bool gic_enable_quirk_asr8601(void *data) return true; } +static bool gic_enable_quirk_arm64_2941627(void *data) +{ + static_branch_enable(&gic_arm64_2941627_erratum); + return true; +} + static const struct gic_quirk gic_quirks[] = { { .desc = "GICv3: Qualcomm MSM8996 broken firmware", @@ -1863,6 +1904,25 @@ static const struct gic_quirk gic_quirks[] = { .mask = 0xffffffff, .init = gic_enable_quirk_nvidia_t241, }, + { + /* + * GIC-700: 2941627 workaround - IP variant [0,1] + * + */ + .desc = "GICv3: ARM64 erratum 2941627", + .iidr = 0x0400043b, + .mask = 0xff0e0fff, + .init = gic_enable_quirk_arm64_2941627, + }, + { + /* + * GIC-700: 2941627 workaround - IP variant [2] + */ + .desc = "GICv3: ARM64 erratum 2941627", + .iidr = 0x0402043b, + .mask = 0xff0f0fff, + .init = gic_enable_quirk_arm64_2941627, + }, { } }; -- cgit v1.2.3