Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/lin…

…ux/kernel/git/tip/tip

Pull more irq updates from Thomas Gleixner:
 "The second part of irq related updates:

   - Provide EOImode for GIC[V3] irq chips, which is a prerequisite for
     direct interrupt handling in [KVM] guests"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/GIC: Fix EOImode setting for non-DT/ACPI systems
  irqchip/GIC: Don't deactivate interrupts forwarded to a guest
  irqchip/GIC: Convert to EOImode == 1
  irqchip/GICv3: Don't deactivate interrupts forwarded to a guest
  irqchip/GICv3: Convert to EOImode == 1

drivers/irqchip/irq-gic-v3.c

@@ -31,6 +31,7 @@
 #include <asm/cputype.h>
 #include <asm/exception.h>
 #include <asm/smp_plat.h>
+#include <asm/virt.h>
 
 #include "irq-gic-common.h"
 
@@ -50,6 +51,7 @@ struct gic_chip_data {
 };
 
 static struct gic_chip_data gic_data __read_mostly;
+static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
 
 #define gic_data_rdist()		(this_cpu_ptr(gic_data.rdists.rdist))
 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
@@ -68,6 +70,11 @@ static inline int gic_irq_in_rdist(struct irq_data *d)
 	return gic_irq(d) < 32;
 }
 
+static inline bool forwarded_irq(struct irq_data *d)
+{
+	return d->handler_data != NULL;
+}
+
 static inline void __iomem *gic_dist_base(struct irq_data *d)
 {
 	if (gic_irq_in_rdist(d))	/* SGI+PPI -> SGI_base for this CPU */
@@ -231,6 +238,21 @@ static void gic_mask_irq(struct irq_data *d)
 	gic_poke_irq(d, GICD_ICENABLER);
 }
 
+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, GICD_ICACTIVER);
+}
+
 static void gic_unmask_irq(struct irq_data *d)
 {
 	gic_poke_irq(d, GICD_ISENABLER);
@@ -296,6 +318,17 @@ static void gic_eoi_irq(struct irq_data *d)
 	gic_write_eoir(gic_irq(d));
 }
 
+static void gic_eoimode1_eoi_irq(struct irq_data *d)
+{
+	/*
+	 * No need to deactivate an LPI, or an interrupt that
+	 * is is getting forwarded to a vcpu.
+	 */
+	if (gic_irq(d) >= 8192 || forwarded_irq(d))
+		return;
+	gic_write_dir(gic_irq(d));
+}
+
 static int gic_set_type(struct irq_data *d, unsigned int type)
 {
 	unsigned int irq = gic_irq(d);
@@ -322,6 +355,12 @@ static int gic_set_type(struct irq_data *d, unsigned int type)
 	return gic_configure_irq(irq, type, base, rwp_wait);
 }
 
+static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
+{
+	d->handler_data = vcpu;
+	return 0;
+}
+
 static u64 gic_mpidr_to_affinity(u64 mpidr)
 {
 	u64 aff;
@@ -343,15 +382,26 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs
 
 		if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
 			int err;
+
+			if (static_key_true(&supports_deactivate))
+				gic_write_eoir(irqnr);
+
 			err = handle_domain_irq(gic_data.domain, irqnr, regs);
 			if (err) {
 				WARN_ONCE(true, "Unexpected interrupt received!\n");
-				gic_write_eoir(irqnr);
+				if (static_key_true(&supports_deactivate)) {
+					if (irqnr < 8192)
+						gic_write_dir(irqnr);
+				} else {
+					gic_write_eoir(irqnr);
+				}
 			}
 			continue;
 		}
 		if (irqnr < 16) {
 			gic_write_eoir(irqnr);
+			if (static_key_true(&supports_deactivate))
+				gic_write_dir(irqnr);
 #ifdef CONFIG_SMP
 			handle_IPI(irqnr, regs);
 #else
@@ -451,8 +501,13 @@ static void gic_cpu_sys_reg_init(void)
 	/* Set priority mask register */
 	gic_write_pmr(DEFAULT_PMR_VALUE);
 
-	/* EOI deactivates interrupt too (mode 0) */
-	gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
+	if (static_key_true(&supports_deactivate)) {
+		/* EOI drops priority only (mode 1) */
+		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop);
+	} else {
+		/* EOI deactivates interrupt too (mode 0) */
+		gic_write_ctlr(ICC_CTLR_EL1_EOImode_drop_dir);
+	}
 
 	/* ... and let's hit the road... */
 	gic_write_grpen1(1);
@@ -661,11 +716,29 @@ static struct irq_chip gic_chip = {
 	.flags			= IRQCHIP_SET_TYPE_MASKED,
 };
 
+static struct irq_chip gic_eoimode1_chip = {
+	.name			= "GICv3",
+	.irq_mask		= gic_eoimode1_mask_irq,
+	.irq_unmask		= gic_unmask_irq,
+	.irq_eoi		= gic_eoimode1_eoi_irq,
+	.irq_set_type		= gic_set_type,
+	.irq_set_affinity	= gic_set_affinity,
+	.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,
+};
+
 #define GIC_ID_NR		(1U << gic_data.rdists.id_bits)
 
 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))
+		chip = &gic_eoimode1_chip;
+
 	/* SGIs are private to the core kernel */
 	if (hw < 16)
 		return -EPERM;
@@ -679,21 +752,21 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
 	/* PPIs */
 	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);
 	}
 	/* SPIs */
 	if (hw >= 32 && hw < gic_data.irq_nr) {
-		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);
 	}
 	/* LPIs */
 	if (hw >= 8192 && hw < GIC_ID_NR) {
 		if (!gic_dist_supports_lpis())
 			return -EPERM;
-		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);
 	}
@@ -820,6 +893,12 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare
 	if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
 		redist_stride = 0;
 
+	if (!is_hyp_mode_available())
+		static_key_slow_dec(&supports_deactivate);
+
+	if (static_key_true(&supports_deactivate))
+		pr_info("GIC: Using split EOI/Deactivate mode\n");
+
 	gic_data.dist_base = dist_base;
 	gic_data.redist_regions = rdist_regs;
 	gic_data.nr_redist_regions = nr_redist_regions;