arm64: ignore DT memreserve entries when booting in UEFI mode

UEFI provides its own method for marking regions to reserve, via the
memory map which is also used to initialise memblock. So when using the
UEFI memory map, ignore any memreserve entries present in the DT.

Reported-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

2 files changed, 5 insertions, 1 deletions

diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index e72f3100958f..24f0c6fb61d8 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -188,6 +188,8 @@ static __init void reserve_regions(void)
                 if (uefi_debug)
                         pr_cont("\n");
         }
+
+        set_bit(EFI_MEMMAP, &efi.flags);
 }
 
 
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 5b4526ee3a01..5472c2401876 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -32,6 +32,7 @@
 #include <linux/of_fdt.h>
 #include <linux/dma-mapping.h>
 #include <linux/dma-contiguous.h>
+#include <linux/efi.h>
 
 #include <asm/fixmap.h>
 #include <asm/sections.h>
@@ -148,7 +149,8 @@ void __init arm64_memblock_init(void)
                 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
 #endif
 
-        early_init_fdt_scan_reserved_mem();
+        if (!efi_enabled(EFI_MEMMAP))
+                early_init_fdt_scan_reserved_mem();
 
         /* 4GB maximum for 32-bit only capable devices */
         if (IS_ENABLED(CONFIG_ZONE_DMA))