diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 74c22741f3ce..f860733d3e4e 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -47,6 +47,8 @@ #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; @@ -3065,15 +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 | @@ -3163,7 +3163,8 @@ out: 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); } @@ -5202,6 +5203,38 @@ int its_cpu_init(void) return 0; } +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: + gic_data_rdist()->flags |= RD_LOCAL_MEMRESERVE_DONE; + return ret; +} + static const struct of_device_id its_device_id[] = { { .compatible = "arm,gic-v3-its", }, {}, @@ -5385,6 +5418,23 @@ static void __init its_acpi_probe(void) 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; + + state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + "irqchip/arm/gicv3/memreserve:online", + its_cpu_memreserve_lpi, + NULL); + if (state < 0) + return state; + + return 0; +} + int __init its_init(struct fwnode_handle *handle, struct rdists *rdists, struct irq_domain *parent_domain) { diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index daec3309b014..9fa3e1d16721 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -1802,6 +1802,7 @@ static int __init gic_init_bases(void __iomem *dist_base, if (gic_dist_supports_lpis()) { its_init(handle, &gic_data.rdists, gic_data.domain); its_cpu_init(); + its_lpi_memreserve_init(); } else { if (IS_ENABLED(CONFIG_ARM_GIC_V2M)) gicv2m_init(handle, gic_data.domain); diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 0dc34d7d735a..51b85506ae90 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -632,6 +632,7 @@ struct rdists { struct irq_domain; struct fwnode_handle; +int __init its_lpi_memreserve_init(void); int its_cpu_init(void); int its_init(struct fwnode_handle *handle, struct rdists *rdists, struct irq_domain *domain);