irqchip/gic: Use IRQD_FORWARDED_TO_VCPU flag
[linux-drm-fsl-dcu.git] / drivers / irqchip / irq-gic.c
index aa3e7b8a69c4349bcd775c7c796062bda3b392f2..9bccdd295769216accf1c628674e158550110600 100644 (file)
@@ -47,6 +47,7 @@
 #include <asm/irq.h>
 #include <asm/exception.h>
 #include <asm/smp_plat.h>
+#include <asm/virt.h>
 
 #include "irq-gic-common.h"
 
@@ -82,6 +83,8 @@ static DEFINE_RAW_SPINLOCK(irq_controller_lock);
 #define NR_GIC_CPU_IF 8
 static u8 gic_cpu_map[NR_GIC_CPU_IF] __read_mostly;
 
+static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
+
 #ifndef MAX_GIC_NR
 #define MAX_GIC_NR     1
 #endif
@@ -137,6 +140,17 @@ static inline unsigned int gic_irq(struct irq_data *d)
        return d->hwirq;
 }
 
+static inline bool cascading_gic_irq(struct irq_data *d)
+{
+       void *data = irq_data_get_irq_handler_data(d);
+
+       /*
+        * If handler_data is set, this is a cascading interrupt, and
+        * it cannot possibly be forwarded.
+        */
+       return data != NULL;
+}
+
 /*
  * Routines to acknowledge, disable and enable interrupts
  */
@@ -157,6 +171,21 @@ static void gic_mask_irq(struct irq_data *d)
        gic_poke_irq(d, GIC_DIST_ENABLE_CLEAR);
 }
 
+static void gic_eoimode1_mask_irq(struct irq_data *d)
+{
+       gic_mask_irq(d);
+       /*
+        * When masking a forwarded interrupt, make sure it is
+        * deactivated as well.
+        *
+        * This ensures that an interrupt that is getting
+        * disabled/masked will not get "stuck", because there is
+        * noone to deactivate it (guest is being terminated).
+        */
+       if (irqd_is_forwarded_to_vcpu(d))
+               gic_poke_irq(d, GIC_DIST_ACTIVE_CLEAR);
+}
+
 static void gic_unmask_irq(struct irq_data *d)
 {
        gic_poke_irq(d, GIC_DIST_ENABLE_SET);
@@ -167,6 +196,15 @@ static void gic_eoi_irq(struct irq_data *d)
        writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_EOI);
 }
 
+static void gic_eoimode1_eoi_irq(struct irq_data *d)
+{
+       /* Do not deactivate an IRQ forwarded to a vcpu. */
+       if (irqd_is_forwarded_to_vcpu(d))
+               return;
+
+       writel_relaxed(gic_irq(d), gic_cpu_base(d) + GIC_CPU_DEACTIVATE);
+}
+
 static int gic_irq_set_irqchip_state(struct irq_data *d,
                                     enum irqchip_irq_state which, bool val)
 {
@@ -233,6 +271,19 @@ static int gic_set_type(struct irq_data *d, unsigned int type)
        return gic_configure_irq(gicirq, type, base, NULL);
 }
 
+static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
+{
+       /* Only interrupts on the primary GIC can be forwarded to a vcpu. */
+       if (cascading_gic_irq(d))
+               return -EINVAL;
+
+       if (vcpu)
+               irqd_set_forwarded_to_vcpu(d);
+       else
+               irqd_clr_forwarded_to_vcpu(d);
+       return 0;
+}
+
 #ifdef CONFIG_SMP
 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
                            bool force)
@@ -272,11 +323,15 @@ static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
                irqnr = irqstat & GICC_IAR_INT_ID_MASK;
 
                if (likely(irqnr > 15 && irqnr < 1021)) {
+                       if (static_key_true(&supports_deactivate))
+                               writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
                        handle_domain_irq(gic->domain, irqnr, regs);
                        continue;
                }
                if (irqnr < 16) {
                        writel_relaxed(irqstat, cpu_base + GIC_CPU_EOI);
+                       if (static_key_true(&supports_deactivate))
+                               writel_relaxed(irqstat, cpu_base + GIC_CPU_DEACTIVATE);
 #ifdef CONFIG_SMP
                        handle_IPI(irqnr, regs);
 #endif
@@ -329,6 +384,23 @@ static struct irq_chip gic_chip = {
                                  IRQCHIP_MASK_ON_SUSPEND,
 };
 
+static struct irq_chip gic_eoimode1_chip = {
+       .name                   = "GICv2",
+       .irq_mask               = gic_eoimode1_mask_irq,
+       .irq_unmask             = gic_unmask_irq,
+       .irq_eoi                = gic_eoimode1_eoi_irq,
+       .irq_set_type           = gic_set_type,
+#ifdef CONFIG_SMP
+       .irq_set_affinity       = gic_set_affinity,
+#endif
+       .irq_get_irqchip_state  = gic_irq_get_irqchip_state,
+       .irq_set_irqchip_state  = gic_irq_set_irqchip_state,
+       .irq_set_vcpu_affinity  = gic_irq_set_vcpu_affinity,
+       .flags                  = IRQCHIP_SET_TYPE_MASKED |
+                                 IRQCHIP_SKIP_SET_WAKE |
+                                 IRQCHIP_MASK_ON_SUSPEND,
+};
+
 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
 {
        if (gic_nr >= MAX_GIC_NR)
@@ -360,6 +432,10 @@ 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;
+
+       if (static_key_true(&supports_deactivate))
+               mode = GIC_CPU_CTRL_EOImodeNS;
 
        /*
        * Preserve bypass disable bits to be written back later
@@ -367,7 +443,7 @@ static void gic_cpu_if_up(struct gic_chip_data *gic)
        bypass = readl(cpu_base + GIC_CPU_CTRL);
        bypass &= GICC_DIS_BYPASS_MASK;
 
-       writel_relaxed(bypass | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
+       writel_relaxed(bypass | mode | GICC_ENABLE, cpu_base + GIC_CPU_CTRL);
 }
 
 
@@ -803,13 +879,20 @@ void __init gic_init_physaddr(struct device_node *node)
 static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
                                irq_hw_number_t hw)
 {
+       struct irq_chip *chip = &gic_chip;
+
+       if (static_key_true(&supports_deactivate)) {
+               if (d->host_data == (void *)&gic_data[0])
+                       chip = &gic_eoimode1_chip;
+       }
+
        if (hw < 32) {
                irq_set_percpu_devid(irq);
-               irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
+               irq_domain_set_info(d, irq, hw, chip, d->host_data,
                                    handle_percpu_devid_irq, NULL, NULL);
                set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
        } else {
-               irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
+               irq_domain_set_info(d, irq, hw, chip, d->host_data,
                                    handle_fasteoi_irq, NULL, NULL);
                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
        }
@@ -894,7 +977,7 @@ static const struct irq_domain_ops gic_irq_domain_ops = {
        .xlate = gic_irq_domain_xlate,
 };
 
-void __init gic_init_bases(unsigned int gic_nr, int irq_start,
+static void __init __gic_init_bases(unsigned int gic_nr, int irq_start,
                           void __iomem *dist_base, void __iomem *cpu_base,
                           u32 percpu_offset, struct device_node *node)
 {
@@ -995,6 +1078,8 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
                register_cpu_notifier(&gic_cpu_notifier);
 #endif
                set_handle_irq(gic_handle_irq);
+               if (static_key_true(&supports_deactivate))
+                       pr_info("GIC: Using split EOI/Deactivate mode\n");
        }
 
        gic_dist_init(gic);
@@ -1002,9 +1087,60 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
        gic_pm_init(gic);
 }
 
+void __init gic_init_bases(unsigned int gic_nr, int irq_start,
+                          void __iomem *dist_base, void __iomem *cpu_base,
+                          u32 percpu_offset, struct device_node *node)
+{
+       /*
+        * Non-DT/ACPI systems won't run a hypervisor, so let's not
+        * bother with these...
+        */
+       static_key_slow_dec(&supports_deactivate);
+       __gic_init_bases(gic_nr, irq_start, dist_base, cpu_base,
+                        percpu_offset, node);
+}
+
 #ifdef CONFIG_OF
 static int gic_cnt __initdata;
 
+static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
+{
+       struct resource cpuif_res;
+
+       of_address_to_resource(node, 1, &cpuif_res);
+
+       if (!is_hyp_mode_available())
+               return false;
+       if (resource_size(&cpuif_res) < SZ_8K)
+               return false;
+       if (resource_size(&cpuif_res) == SZ_128K) {
+               u32 val_low, val_high;
+
+               /*
+                * Verify that we have the first 4kB of a GIC400
+                * aliased over the first 64kB by checking the
+                * GICC_IIDR register on both ends.
+                */
+               val_low = readl_relaxed(*base + GIC_CPU_IDENT);
+               val_high = readl_relaxed(*base + GIC_CPU_IDENT + 0xf000);
+               if ((val_low & 0xffff0fff) != 0x0202043B ||
+                   val_low != val_high)
+                       return false;
+
+               /*
+                * Move the base up by 60kB, so that we have a 8kB
+                * contiguous region, which allows us to use GICC_DIR
+                * at its normal offset. Please pass me that bucket.
+                */
+               *base += 0xf000;
+               cpuif_res.start += 0xf000;
+               pr_warn("GIC: Adjusting CPU interface base to %pa",
+                       &cpuif_res.start);
+       }
+
+       return true;
+}
+
 static int __init
 gic_of_init(struct device_node *node, struct device_node *parent)
 {
@@ -1022,10 +1158,17 @@ gic_of_init(struct device_node *node, struct device_node *parent)
        cpu_base = of_iomap(node, 1);
        WARN(!cpu_base, "unable to map gic cpu registers\n");
 
+       /*
+        * Disable split EOI/Deactivate if either HYP is not available
+        * or the CPU interface is too small.
+        */
+       if (gic_cnt == 0 && !gic_check_eoimode(node, &cpu_base))
+               static_key_slow_dec(&supports_deactivate);
+
        if (of_property_read_u32(node, "cpu-offset", &percpu_offset))
                percpu_offset = 0;
 
-       gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
+       __gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset, node);
        if (!gic_cnt)
                gic_init_physaddr(node);
 
@@ -1140,12 +1283,20 @@ gic_v2_acpi_init(struct acpi_table_header *table)
                return -ENOMEM;
        }
 
+       /*
+        * Disable split EOI/Deactivate if HYP is not available. ACPI
+        * guarantees that we'll always have a GICv2, so the CPU
+        * interface will always be the right size.
+        */
+       if (!is_hyp_mode_available())
+               static_key_slow_dec(&supports_deactivate);
+
        /*
         * Initialize zero GIC instance (no multi-GIC support). Also, set GIC
         * as default IRQ domain to allow for GSI registration and GSI to IRQ
         * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()).
         */
-       gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
+       __gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL);
        irq_set_default_host(gic_data[0].domain);
 
        acpi_irq_model = ACPI_IRQ_MODEL_GIC;