[PATCH v2 2/4] efi/arm: map UEFI memory map even w/o runtime services enabled

AKASHI Takahiro takahiro.akashi at linaro.org
Mon Jun 18 23:44:22 PDT 2018


Under the current implementation, UEFI memory map will be mapped and made
available in virtual mappings only if runtime services are enabled.
But in a later patch, we want to use UEFI memory map in acpi_os_ioremap()
to create mappings of ACPI tables using memory attributes described in
UEFI memory map.

So, as a first step, arm_enter_runtime_services() will be modified
so that UEFI memory map will be always accessible.

See a relevant commit:
    arm64: acpi: fix alignment fault in accessing ACPI tables

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
Cc: Ard Biesheuvel <ard.biesheuvel at linaro.org>
---
 drivers/firmware/efi/arm-runtime.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 5889cbea60b8..30ac5c82051e 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -115,6 +115,13 @@ static int __init arm_enable_runtime_services(void)
 		return 0;
 	}
 
+	mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
+
+	if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
+		pr_err("Failed to remap EFI memory map\n");
+		return 0;
+	}
+
 	if (efi_runtime_disabled()) {
 		pr_info("EFI runtime services will be disabled.\n");
 		return 0;
@@ -127,13 +134,6 @@ static int __init arm_enable_runtime_services(void)
 
 	pr_info("Remapping and enabling EFI services.\n");
 
-	mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
-
-	if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
-		pr_err("Failed to remap EFI memory map\n");
-		return -ENOMEM;
-	}
-
 	if (!efi_virtmap_init()) {
 		pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
 		return -ENOMEM;
-- 
2.17.0




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