diff options
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/efi.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index e1010d450b65..2e2fbdec0845 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -150,6 +150,38 @@ err_put: subsys_initcall(efisubsys_init); +/* + * We can't ioremap data in EFI boot services RAM, because we've already mapped + * it as RAM. So, look it up in the existing EFI memory map instead. Only + * callable after efi_enter_virtual_mode and before efi_free_boot_services. + */ +void __iomem *efi_lookup_mapped_addr(u64 phys_addr) +{ + struct efi_memory_map *map; + void *p; + map = efi.memmap; + if (!map) + return NULL; + if (WARN_ON(!map->map)) + return NULL; + for (p = map->map; p < map->map_end; p += map->desc_size) { + efi_memory_desc_t *md = p; + u64 size = md->num_pages << EFI_PAGE_SHIFT; + u64 end = md->phys_addr + size; + if (!(md->attribute & EFI_MEMORY_RUNTIME) && + md->type != EFI_BOOT_SERVICES_CODE && + md->type != EFI_BOOT_SERVICES_DATA) + continue; + if (!md->virt_addr) + continue; + if (phys_addr >= md->phys_addr && phys_addr < end) { + phys_addr += md->virt_addr - md->phys_addr; + return (__force void __iomem *)(unsigned long)phys_addr; + } + } + return NULL; +} + static __initdata efi_config_table_type_t common_tables[] = { {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20}, {ACPI_TABLE_GUID, "ACPI", &efi.acpi}, |