diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/irqchip/irq-gic.c | 183 |
1 files changed, 169 insertions, 14 deletions
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c index 25a7ad3a8aaa..a315b5859764 100644 --- a/drivers/irqchip/irq-gic.c +++ b/drivers/irqchip/irq-gic.c @@ -41,6 +41,7 @@ #include <linux/irqchip.h> #include <linux/irqchip/chained_irq.h> #include <linux/irqchip/arm-gic.h> +#include <linux/ratelimit.h> #include <asm/cputype.h> #include <asm/irq.h> @@ -63,6 +64,10 @@ static void gic_check_cpu_features(void) #define gic_check_cpu_features() do { } while(0) #endif +#ifndef SMP_IPI_FIQ_MASK +#define SMP_IPI_FIQ_MASK 0 +#endif + union gic_base { void __iomem *common_base; void __percpu * __iomem *percpu_base; @@ -83,6 +88,7 @@ struct gic_chip_data { #endif struct irq_domain *domain; unsigned int gic_irqs; + bool sgi_with_nsatt; #ifdef CONFIG_GIC_NON_BANKED void __iomem *(*get_base)(union gic_base *); #endif @@ -347,12 +353,52 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val, } #endif +/* + * Fully acknowledge (ack, eoi and deactivate) any outstanding FIQ-based IPI, + * otherwise do nothing. + */ +static void __maybe_unused gic_handle_fiq(struct pt_regs *regs) +{ + struct gic_chip_data *gic = &gic_data[0]; + void __iomem *cpu_base = gic_data_cpu_base(gic); + u32 hppstat, hppnr, irqstat, irqnr; + + do { + hppstat = readl_relaxed(cpu_base + GIC_CPU_HIGHPRI); + hppnr = hppstat & GICC_IAR_INT_ID_MASK; + if (!(hppnr < 16 && BIT(hppnr) & SMP_IPI_FIQ_MASK)) + break; + + irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK); + irqnr = irqstat & GICC_IAR_INT_ID_MASK; + + writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI); + if (static_key_true(&supports_deactivate)) + writel_relaxed(irqstat, cpu_base + GIC_CPU_DEACTIVATE); + + if (WARN_RATELIMIT(irqnr > 16, + "Unexpected irqnr %u (bad prioritization?)\n", + irqnr)) + continue; +#ifdef CONFIG_SMP + handle_IPI(irqnr, regs); +#endif + } while (1); +} + static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs) { u32 irqstat, irqnr; struct gic_chip_data *gic = &gic_data[0]; void __iomem *cpu_base = gic_data_cpu_base(gic); +#ifdef CONFIG_ARM + if (in_nmi()) { + gic_handle_fiq(regs); + return; + } +#endif + do { irqstat = readl_relaxed(cpu_base + GIC_CPU_INTACK); irqnr = irqstat & GICC_IAR_INT_ID_MASK; @@ -429,6 +475,55 @@ static struct irq_chip gic_eoimode1_chip = { IRQCHIP_MASK_ON_SUSPEND, }; +/* + * Shift an interrupt between Group 0 and Group 1. + * + * In addition to changing the group we also modify the priority to + * match what "ARM strongly recommends" for a system where no Group 1 + * interrupt must ever preempt a Group 0 interrupt. + * + * It is safe to call this function on systems which do not support + * grouping (it will have no effect). + */ +static void gic_set_group_irq(struct gic_chip_data *gic, unsigned int hwirq, + int group) +{ + void __iomem *base = gic_data_dist_base(gic); + unsigned int grp_reg = hwirq / 32 * 4; + u32 grp_mask = BIT(hwirq % 32); + u32 grp_val; + + unsigned int pri_reg = (hwirq / 4) * 4; + u32 pri_mask = BIT(7 + ((hwirq % 4) * 8)); + u32 pri_val; + + /* + * Systems which do not support grouping will have not have + * the EnableGrp1 bit set. + */ + if (!(GICD_ENABLE_GRP1 & readl_relaxed(base + GIC_DIST_CTRL))) + return; + + raw_spin_lock(&irq_controller_lock); + + grp_val = readl_relaxed(base + GIC_DIST_IGROUP + grp_reg); + pri_val = readl_relaxed(base + GIC_DIST_PRI + pri_reg); + + if (group) { + grp_val |= grp_mask; + pri_val |= pri_mask; + } else { + grp_val &= ~grp_mask; + pri_val &= ~pri_mask; + } + + writel_relaxed(grp_val, base + GIC_DIST_IGROUP + grp_reg); + writel_relaxed(pri_val, base + GIC_DIST_PRI + pri_reg); + + raw_spin_unlock(&irq_controller_lock); +} + + void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq) { BUG_ON(gic_nr >= CONFIG_ARM_GIC_MAX_NR); @@ -458,19 +553,27 @@ static u8 gic_get_cpumask(struct gic_chip_data *gic) static void gic_cpu_if_up(struct gic_chip_data *gic) { void __iomem *cpu_base = gic_data_cpu_base(gic); - u32 bypass = 0; - u32 mode = 0; + void __iomem *dist_base = gic_data_dist_base(gic); + u32 ctrl = 0; - if (gic == &gic_data[0] && static_key_true(&supports_deactivate)) - mode = GIC_CPU_CTRL_EOImodeNS; + /* + * Preserve bypass disable bits to be written back later + */ + ctrl = readl(cpu_base + GIC_CPU_CTRL); + ctrl &= GICC_DIS_BYPASS_MASK; /* - * Preserve bypass disable bits to be written back later - */ - bypass = readl(cpu_base + GIC_CPU_CTRL); - bypass &= GICC_DIS_BYPASS_MASK; + * If EnableGrp1 is set in the distributor then enable group 1 + * support for this CPU (and route group 0 interrupts to FIQ). + */ + if (GICD_ENABLE_GRP1 & readl_relaxed(dist_base + GIC_DIST_CTRL)) + ctrl |= GICC_COMMON_BPR | GICC_FIQ_EN | GICC_ACK_CTL | + GICC_ENABLE_GRP1; + + if (gic == &gic_data[0] && static_key_true(&supports_deactivate)) + ctrl |= GIC_CPU_CTRL_EOImodeNS; - writel_relaxed(bypass | mode | GICC_ENABLE, cpu_base + GIC_CPU_CTRL); + writel_relaxed(ctrl | GICC_ENABLE, cpu_base + GIC_CPU_CTRL); } @@ -494,7 +597,31 @@ static void __init gic_dist_init(struct gic_chip_data *gic) gic_dist_config(base, gic_irqs, NULL); - writel_relaxed(GICD_ENABLE, base + GIC_DIST_CTRL); + /* + * Set EnableGrp1/EnableGrp0 (bit 1 and 0) or EnableGrp (bit 0 only, + * bit 1 ignored) depending on current security mode. + */ + writel_relaxed(GICD_ENABLE_GRP1 | GICD_ENABLE, base + GIC_DIST_CTRL); + + /* + * Some GICv1 devices (even those with security extensions) do not + * implement EnableGrp1 meaning some parts of the above write may + * be ignored. We will only enable FIQ support if the bit can be set. + */ + if (GICD_ENABLE_GRP1 & readl_relaxed(base + GIC_DIST_CTRL)) { + /* Place all SPIs in group 1 (signally with IRQ). */ + for (i = 32; i < gic_irqs; i += 32) + writel_relaxed(0xffffffff, + base + GIC_DIST_IGROUP + i * 4 / 32); + + /* + * If the GIC supports the security extension then SGIs + * will be filtered based on the value of NSATT. If the + * GIC has this support then enable NSATT support. + */ + if (GICD_SECURITY_EXTN & readl_relaxed(base + GIC_DIST_CTR)) + gic->sgi_with_nsatt = true; + } } static void gic_cpu_init(struct gic_chip_data *gic) @@ -503,6 +630,7 @@ static void gic_cpu_init(struct gic_chip_data *gic) void __iomem *base = gic_data_cpu_base(gic); unsigned int cpu_mask, cpu = smp_processor_id(); int i; + unsigned long ipi_fiq_mask, fiq; /* * Setting up the CPU map is only relevant for the primary GIC @@ -528,6 +656,23 @@ static void gic_cpu_init(struct gic_chip_data *gic) gic_cpu_config(dist_base, NULL); + /* + * If the distributor is configured to support interrupt grouping + * then set all SGI and PPI interrupts that are not set in + * SMP_IPI_FIQ_MASK to group1 and ensure any remaining group 0 + * interrupts have the right priority. + * + * Note that IGROUP[0] is banked, meaning that although we are + * writing to a distributor register we are actually performing + * part of the per-cpu initialization. + */ + if (GICD_ENABLE_GRP1 & readl_relaxed(dist_base + GIC_DIST_CTRL)) { + ipi_fiq_mask = SMP_IPI_FIQ_MASK; + writel_relaxed(~ipi_fiq_mask, dist_base + GIC_DIST_IGROUP + 0); + for_each_set_bit(fiq, &ipi_fiq_mask, 16) + gic_set_group_irq(gic, fiq, 0); + } + writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK); gic_cpu_if_up(gic); } @@ -542,7 +687,8 @@ int gic_cpu_if_down(unsigned int gic_nr) cpu_base = gic_data_cpu_base(&gic_data[gic_nr]); val = readl(cpu_base + GIC_CPU_CTRL); - val &= ~GICC_ENABLE; + val &= ~(GICC_COMMON_BPR | GICC_FIQ_EN | GICC_ACK_CTL | + GICC_ENABLE_GRP1 | GICC_ENABLE); writel_relaxed(val, cpu_base + GIC_CPU_CTRL); return 0; @@ -635,7 +781,8 @@ static void gic_dist_restore(unsigned int gic_nr) dist_base + GIC_DIST_ACTIVE_SET + i * 4); } - writel_relaxed(GICD_ENABLE, dist_base + GIC_DIST_CTRL); + writel_relaxed(GICD_ENABLE_GRP1 | GICD_ENABLE, + dist_base + GIC_DIST_CTRL); } static void gic_cpu_save(unsigned int gic_nr) @@ -779,6 +926,8 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) { int cpu; unsigned long map = 0; + unsigned long softint; + void __iomem *dist_base; gic_migration_lock(); @@ -786,14 +935,20 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) for_each_cpu(cpu, mask) map |= gic_cpu_map[cpu]; + /* This always happens on GIC0 */ + dist_base = gic_data_dist_base(&gic_data[0]); + /* * Ensure that stores to Normal memory are visible to the * other CPUs before they observe us issuing the IPI. */ dmb(ishst); - /* this always happens on GIC0 */ - writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT); + softint = map << 16 | irq; + + writel_relaxed(softint, dist_base + GIC_DIST_SOFTINT); + if (gic_data[0].sgi_with_nsatt) + writel_relaxed(softint | 0x8000, dist_base + GIC_DIST_SOFTINT); gic_migration_unlock(); } |