1 files changed, 184 insertions, 42 deletions

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 4dd88264dff5..e6b7ed537952 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -38,6 +38,7 @@
 #include <linux/interrupt.h>
 #include <linux/percpu.h>
 #include <linux/slab.h>
+#include <linux/irqchip.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irqchip/arm-gic.h>
 #include <linux/irqchip/arm-gic-acpi.h>
@@ -46,9 +47,9 @@
 #include <asm/irq.h>
 #include <asm/exception.h>
 #include <asm/smp_plat.h>
+#include <asm/virt.h>
 
 #include "irq-gic-common.h"
-#include "irqchip.h"
 
 union gic_base {
 	void __iomem *common_base;
@@ -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 +140,36 @@ 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 pointing to one of the secondary GICs, then
+	 * this is a cascading interrupt, and it cannot possibly be
+	 * forwarded.
+	 */
+	if (data >= (void *)(gic_data + 1) &&
+	    data <  (void *)(gic_data + MAX_GIC_NR))
+		return true;
+
+	return false;
+}
+
+static inline bool forwarded_irq(struct irq_data *d)
+{
+	/*
+	 * A forwarded interrupt:
+	 * - is on the primary GIC
+	 * - has its handler_data set to a value
+	 * - that isn't a secondary GIC
+	 */
+	if (d->handler_data && !cascading_gic_irq(d))
+		return true;
+
+	return false;
+}
+
 /*
  * Routines to acknowledge, disable and enable interrupts
  */
@@ -157,6 +190,21 @@ 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 (forwarded_irq(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 +215,15 @@ 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 (forwarded_irq(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 +290,16 @@ 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;
+
+	d->handler_data = vcpu;
+	return 0;
+}
+
 #ifdef CONFIG_SMP
 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 			    bool force)
@@ -272,11 +339,15 @@ 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
@@ -288,8 +359,8 @@ static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
 
 static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
 {
-	struct gic_chip_data *chip_data = irq_get_handler_data(irq);
-	struct irq_chip *chip = irq_get_chip(irq);
+	struct gic_chip_data *chip_data = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
 	unsigned int cascade_irq, gic_irq;
 	unsigned long status;
 
@@ -324,16 +395,34 @@ static struct irq_chip gic_chip = {
 #endif
 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
-	.flags			= IRQCHIP_SET_TYPE_MASKED,
+	.flags			= IRQCHIP_SET_TYPE_MASKED |
+				  IRQCHIP_SKIP_SET_WAKE |
+				  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)
 		BUG();
-	if (irq_set_handler_data(irq, &gic_data[gic_nr]) != 0)
-		BUG();
-	irq_set_chained_handler(irq, gic_handle_cascade_irq);
+	irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq,
+					 &gic_data[gic_nr]);
 }
 
 static u8 gic_get_cpumask(struct gic_chip_data *gic)
@@ -355,10 +444,14 @@ static u8 gic_get_cpumask(struct gic_chip_data *gic)
 	return mask;
 }
 
-static void gic_cpu_if_up(void)
+static void gic_cpu_if_up(struct gic_chip_data *gic)
 {
-	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
+	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
@@ -366,7 +459,7 @@ static void gic_cpu_if_up(void)
 	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);
 }
 
 
@@ -401,34 +494,47 @@ static void gic_cpu_init(struct gic_chip_data *gic)
 	int i;
 
 	/*
-	 * Get what the GIC says our CPU mask is.
+	 * Setting up the CPU map is only relevant for the primary GIC
+	 * because any nested/secondary GICs do not directly interface
+	 * with the CPU(s).
 	 */
-	BUG_ON(cpu >= NR_GIC_CPU_IF);
-	cpu_mask = gic_get_cpumask(gic);
-	gic_cpu_map[cpu] = cpu_mask;
+	if (gic == &gic_data[0]) {
+		/*
+		 * Get what the GIC says our CPU mask is.
+		 */
+		BUG_ON(cpu >= NR_GIC_CPU_IF);
+		cpu_mask = gic_get_cpumask(gic);
+		gic_cpu_map[cpu] = cpu_mask;
 
-	/*
-	 * Clear our mask from the other map entries in case they're
-	 * still undefined.
-	 */
-	for (i = 0; i < NR_GIC_CPU_IF; i++)
-		if (i != cpu)
-			gic_cpu_map[i] &= ~cpu_mask;
+		/*
+		 * Clear our mask from the other map entries in case they're
+		 * still undefined.
+		 */
+		for (i = 0; i < NR_GIC_CPU_IF; i++)
+			if (i != cpu)
+				gic_cpu_map[i] &= ~cpu_mask;
+	}
 
 	gic_cpu_config(dist_base, NULL);
 
 	writel_relaxed(GICC_INT_PRI_THRESHOLD, base + GIC_CPU_PRIMASK);
-	gic_cpu_if_up();
+	gic_cpu_if_up(gic);
 }
 
-void gic_cpu_if_down(void)
+int gic_cpu_if_down(unsigned int gic_nr)
 {
-	void __iomem *cpu_base = gic_data_cpu_base(&gic_data[0]);
+	void __iomem *cpu_base;
 	u32 val = 0;
 
+	if (gic_nr >= MAX_GIC_NR)
+		return -EINVAL;
+
+	cpu_base = gic_data_cpu_base(&gic_data[gic_nr]);
 	val = readl(cpu_base + GIC_CPU_CTRL);
 	val &= ~GICC_ENABLE;
 	writel_relaxed(val, cpu_base + GIC_CPU_CTRL);
+
+	return 0;
 }
 
 #ifdef CONFIG_CPU_PM
@@ -564,7 +670,7 @@ static void gic_cpu_restore(unsigned int gic_nr)
 					dist_base + GIC_DIST_PRI + i * 4);
 
 	writel_relaxed(GICC_INT_PRI_THRESHOLD, cpu_base + GIC_CPU_PRIMASK);
-	gic_cpu_if_up();
+	gic_cpu_if_up(&gic_data[gic_nr]);
 }
 
 static int gic_notifier(struct notifier_block *self, unsigned long cmd,	void *v)
@@ -789,13 +895,20 @@ 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);
 	}
@@ -880,12 +993,7 @@ static const struct irq_domain_ops gic_irq_domain_ops = {
 	.xlate = gic_irq_domain_xlate,
 };
 
-void gic_set_irqchip_flags(unsigned long flags)
-{
-	gic_chip.flags |= flags;
-}
-
-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)
 {
@@ -930,13 +1038,6 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
 	}
 
 	/*
-	 * Initialize the CPU interface map to all CPUs.
-	 * It will be refined as each CPU probes its ID.
-	 */
-	for (i = 0; i < NR_GIC_CPU_IF; i++)
-		gic_cpu_map[i] = 0xff;
-
-	/*
 	 * Find out how many interrupts are supported.
 	 * The GIC only supports up to 1020 interrupt sources.
 	 */
@@ -981,11 +1082,20 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start,
 		return;
 
 	if (gic_nr == 0) {
+		/*
+		 * Initialize the CPU interface map to all CPUs.
+		 * It will be refined as each CPU probes its ID.
+		 * This is only necessary for the primary GIC.
+		 */
+		for (i = 0; i < NR_GIC_CPU_IF; i++)
+			gic_cpu_map[i] = 0xff;
 #ifdef CONFIG_SMP
 		set_smp_cross_call(gic_raise_softirq);
 		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);
@@ -993,6 +1103,19 @@ 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;
 
@@ -1001,6 +1124,7 @@ gic_of_init(struct device_node *node, struct device_node *parent)
 {
 	void __iomem *cpu_base;
 	void __iomem *dist_base;
+	struct resource cpu_res;
 	u32 percpu_offset;
 	int irq;
 
@@ -1013,10 +1137,20 @@ 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");
 
+	of_address_to_resource(node, 1, &cpu_res);
+
+	/*
+	 * Disable split EOI/Deactivate if either HYP is not available
+	 * or the CPU interface is too small.
+	 */
+	if (gic_cnt == 0 && (!is_hyp_mode_available() ||
+			     resource_size(&cpu_res) < SZ_8K))
+		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);
 
@@ -1132,11 +1266,19 @@ gic_v2_acpi_init(struct acpi_table_header *table)
 	}
 
 	/*
+	 * 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;