1 files changed, 175 insertions, 28 deletions

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 0cb584d9815b..9e93ff2b6375 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -46,6 +46,10 @@
 #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING	(1 << 0)
 #define RDIST_FLAGS_RD_TABLES_PREALLOCATED	(1 << 1)
 
+#define RD_LOCAL_LPI_ENABLED                    BIT(0)
+#define RD_LOCAL_PENDTABLE_PREALLOCATED         BIT(1)
+#define RD_LOCAL_MEMRESERVE_DONE                BIT(2)
+
 static u32 lpi_id_bits;
 
 /*
@@ -3044,7 +3048,7 @@ static void its_cpu_init_lpis(void)
 	phys_addr_t paddr;
 	u64 val, tmp;
 
-	if (gic_data_rdist()->lpi_enabled)
+	if (gic_data_rdist()->flags & RD_LOCAL_LPI_ENABLED)
 		return;
 
 	val = readl_relaxed(rbase + GICR_CTLR);
@@ -3063,15 +3067,13 @@ static void its_cpu_init_lpis(void)
 		paddr &= GENMASK_ULL(51, 16);
 
 		WARN_ON(!gic_check_reserved_range(paddr, LPI_PENDBASE_SZ));
-		its_free_pending_table(gic_data_rdist()->pend_page);
-		gic_data_rdist()->pend_page = NULL;
+		gic_data_rdist()->flags |= RD_LOCAL_PENDTABLE_PREALLOCATED;
 
 		goto out;
 	}
 
 	pend_page = gic_data_rdist()->pend_page;
 	paddr = page_to_phys(pend_page);
-	WARN_ON(gic_reserve_range(paddr, LPI_PENDBASE_SZ));
 
 	/* set PROPBASE */
 	val = (gic_rdists->prop_table_pa |
@@ -3158,10 +3160,11 @@ static void its_cpu_init_lpis(void)
 	/* Make sure the GIC has seen the above */
 	dsb(sy);
 out:
-	gic_data_rdist()->lpi_enabled = true;
+	gic_data_rdist()->flags |= RD_LOCAL_LPI_ENABLED;
 	pr_info("GICv3: CPU%d: using %s LPI pending table @%pa\n",
 		smp_processor_id(),
-		gic_data_rdist()->pend_page ? "allocated" : "reserved",
+		gic_data_rdist()->flags & RD_LOCAL_PENDTABLE_PREALLOCATED ?
+		"reserved" : "allocated",
 		&paddr);
 }
 
@@ -4853,6 +4856,38 @@ static struct syscore_ops its_syscore_ops = {
 	.resume = its_restore_enable,
 };
 
+static void __init __iomem *its_map_one(struct resource *res, int *err)
+{
+	void __iomem *its_base;
+	u32 val;
+
+	its_base = ioremap(res->start, SZ_64K);
+	if (!its_base) {
+		pr_warn("ITS@%pa: Unable to map ITS registers\n", &res->start);
+		*err = -ENOMEM;
+		return NULL;
+	}
+
+	val = readl_relaxed(its_base + GITS_PIDR2) & GIC_PIDR2_ARCH_MASK;
+	if (val != 0x30 && val != 0x40) {
+		pr_warn("ITS@%pa: No ITS detected, giving up\n", &res->start);
+		*err = -ENODEV;
+		goto out_unmap;
+	}
+
+	*err = its_force_quiescent(its_base);
+	if (*err) {
+		pr_warn("ITS@%pa: Failed to quiesce, giving up\n", &res->start);
+		goto out_unmap;
+	}
+
+	return its_base;
+
+out_unmap:
+	iounmap(its_base);
+	return NULL;
+}
+
 static int its_init_domain(struct fwnode_handle *handle, struct its_node *its)
 {
 	struct irq_domain *inner_domain;
@@ -4960,29 +4995,14 @@ static int __init its_probe_one(struct resource *res,
 {
 	struct its_node *its;
 	void __iomem *its_base;
-	u32 val, ctlr;
 	u64 baser, tmp, typer;
 	struct page *page;
+	u32 ctlr;
 	int err;
 
-	its_base = ioremap(res->start, SZ_64K);
-	if (!its_base) {
-		pr_warn("ITS@%pa: Unable to map ITS registers\n", &res->start);
-		return -ENOMEM;
-	}
-
-	val = readl_relaxed(its_base + GITS_PIDR2) & GIC_PIDR2_ARCH_MASK;
-	if (val != 0x30 && val != 0x40) {
-		pr_warn("ITS@%pa: No ITS detected, giving up\n", &res->start);
-		err = -ENODEV;
-		goto out_unmap;
-	}
-
-	err = its_force_quiescent(its_base);
-	if (err) {
-		pr_warn("ITS@%pa: Failed to quiesce, giving up\n", &res->start);
-		goto out_unmap;
-	}
+	its_base = its_map_one(res, &err);
+	if (!its_base)
+		return err;
 
 	pr_info("ITS %pR\n", res);
 
@@ -5138,7 +5158,7 @@ static int redist_disable_lpis(void)
 	 *
 	 * If running with preallocated tables, there is nothing to do.
 	 */
-	if (gic_data_rdist()->lpi_enabled ||
+	if ((gic_data_rdist()->flags & RD_LOCAL_LPI_ENABLED) ||
 	    (gic_rdists->flags & RDIST_FLAGS_RD_TABLES_PREALLOCATED))
 		return 0;
 
@@ -5200,6 +5220,69 @@ int its_cpu_init(void)
 	return 0;
 }
 
+static void rdist_memreserve_cpuhp_cleanup_workfn(struct work_struct *work)
+{
+	cpuhp_remove_state_nocalls(gic_rdists->cpuhp_memreserve_state);
+	gic_rdists->cpuhp_memreserve_state = CPUHP_INVALID;
+}
+
+static DECLARE_WORK(rdist_memreserve_cpuhp_cleanup_work,
+		    rdist_memreserve_cpuhp_cleanup_workfn);
+
+static int its_cpu_memreserve_lpi(unsigned int cpu)
+{
+	struct page *pend_page;
+	int ret = 0;
+
+	/* This gets to run exactly once per CPU */
+	if (gic_data_rdist()->flags & RD_LOCAL_MEMRESERVE_DONE)
+		return 0;
+
+	pend_page = gic_data_rdist()->pend_page;
+	if (WARN_ON(!pend_page)) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	/*
+	 * If the pending table was pre-programmed, free the memory we
+	 * preemptively allocated. Otherwise, reserve that memory for
+	 * later kexecs.
+	 */
+	if (gic_data_rdist()->flags & RD_LOCAL_PENDTABLE_PREALLOCATED) {
+		its_free_pending_table(pend_page);
+		gic_data_rdist()->pend_page = NULL;
+	} else {
+		phys_addr_t paddr = page_to_phys(pend_page);
+		WARN_ON(gic_reserve_range(paddr, LPI_PENDBASE_SZ));
+	}
+
+out:
+	/* Last CPU being brought up gets to issue the cleanup */
+	if (!IS_ENABLED(CONFIG_SMP) ||
+	    cpumask_equal(&cpus_booted_once_mask, cpu_possible_mask))
+		schedule_work(&rdist_memreserve_cpuhp_cleanup_work);
+
+	gic_data_rdist()->flags |= RD_LOCAL_MEMRESERVE_DONE;
+	return ret;
+}
+
+/* Mark all the BASER registers as invalid before they get reprogrammed */
+static int __init its_reset_one(struct resource *res)
+{
+	void __iomem *its_base;
+	int err, i;
+
+	its_base = its_map_one(res, &err);
+	if (!its_base)
+		return err;
+
+	for (i = 0; i < GITS_BASER_NR_REGS; i++)
+		gits_write_baser(0, its_base + GITS_BASER + (i << 3));
+
+	iounmap(its_base);
+	return 0;
+}
+
 static const struct of_device_id its_device_id[] = {
 	{	.compatible	= "arm,gic-v3-its",	},
 	{},
@@ -5210,6 +5293,26 @@ static int __init its_of_probe(struct device_node *node)
 	struct device_node *np;
 	struct resource res;
 
+	/*
+	 * Make sure *all* the ITS are reset before we probe any, as
+	 * they may be sharing memory. If any of the ITS fails to
+	 * reset, don't even try to go any further, as this could
+	 * result in something even worse.
+	 */
+	for (np = of_find_matching_node(node, its_device_id); np;
+	     np = of_find_matching_node(np, its_device_id)) {
+		int err;
+
+		if (!of_device_is_available(np) ||
+		    !of_property_read_bool(np, "msi-controller") ||
+		    of_address_to_resource(np, 0, &res))
+			continue;
+
+		err = its_reset_one(&res);
+		if (err)
+			return err;
+	}
+
 	for (np = of_find_matching_node(node, its_device_id); np;
 	     np = of_find_matching_node(np, its_device_id)) {
 		if (!of_device_is_available(np))
@@ -5372,17 +5475,61 @@ dom_err:
 	return err;
 }
 
+static int __init its_acpi_reset(union acpi_subtable_headers *header,
+				 const unsigned long end)
+{
+	struct acpi_madt_generic_translator *its_entry;
+	struct resource res;
+
+	its_entry = (struct acpi_madt_generic_translator *)header;
+	res = (struct resource) {
+		.start	= its_entry->base_address,
+		.end	= its_entry->base_address + ACPI_GICV3_ITS_MEM_SIZE - 1,
+		.flags	= IORESOURCE_MEM,
+	};
+
+	return its_reset_one(&res);
+}
+
 static void __init its_acpi_probe(void)
 {
 	acpi_table_parse_srat_its();
-	acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
-			      gic_acpi_parse_madt_its, 0);
+	/*
+	 * Make sure *all* the ITS are reset before we probe any, as
+	 * they may be sharing memory. If any of the ITS fails to
+	 * reset, don't even try to go any further, as this could
+	 * result in something even worse.
+	 */
+	if (acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
+				  its_acpi_reset, 0) > 0)
+		acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR,
+				      gic_acpi_parse_madt_its, 0);
 	acpi_its_srat_maps_free();
 }
 #else
 static void __init its_acpi_probe(void) { }
 #endif
 
+int __init its_lpi_memreserve_init(void)
+{
+	int state;
+
+	if (!efi_enabled(EFI_CONFIG_TABLES))
+		return 0;
+
+	gic_rdists->cpuhp_memreserve_state = CPUHP_INVALID;
+	state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+				  "irqchip/arm/gicv3/memreserve:online",
+				  its_cpu_memreserve_lpi,
+				  NULL);
+	if (state < 0)
+		return state;
+
+	gic_rdists->cpuhp_memreserve_state = state;
+
+	return 0;
+}
+
 int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
 		    struct irq_domain *parent_domain)
 {