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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2015-10-19 14:19:36 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2015-10-19 17:54:41 +0100 |
| commit | 9d372c9fab34cd8803141871195141995f85c7f7 (patch) | |
| tree | addabfafd3a42eef113fe9e80c3cacaf19bf2755 | |
| parent | 4bf8b96ed3f7e11422d8b4f58cf43896ed02d1f6 (diff) | |
| download | lwn-9d372c9fab34cd8803141871195141995f85c7f7.tar.gz lwn-9d372c9fab34cd8803141871195141995f85c7f7.zip | |
arm64: Add page size to the kernel image header
This patch adds the page size to the arm64 kernel image header
so that one can infer the PAGESIZE used by the kernel. This will
be helpful to diagnose failures to boot the kernel with page size
not supported by the CPU.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | Documentation/arm64/booting.txt | 7 | ||||
| -rw-r--r-- | arch/arm64/kernel/image.h | 5 |
2 files changed, 10 insertions, 2 deletions
diff --git a/Documentation/arm64/booting.txt b/Documentation/arm64/booting.txt index 7d9d3c2286b2..aaf6d77e4148 100644 --- a/Documentation/arm64/booting.txt +++ b/Documentation/arm64/booting.txt @@ -104,7 +104,12 @@ Header notes: - The flags field (introduced in v3.17) is a little-endian 64-bit field composed as follows: Bit 0: Kernel endianness. 1 if BE, 0 if LE. - Bits 1-63: Reserved. + Bit 1-2: Kernel Page size. + 0 - Unspecified. + 1 - 4K + 2 - 16K + 3 - 64K + Bits 3-63: Reserved. - When image_size is zero, a bootloader should attempt to keep as much memory as possible free for use by the kernel immediately after the diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h index 6eb8fee93321..bc2abb8b1599 100644 --- a/arch/arm64/kernel/image.h +++ b/arch/arm64/kernel/image.h @@ -47,7 +47,10 @@ #define __HEAD_FLAG_BE 0 #endif -#define __HEAD_FLAGS (__HEAD_FLAG_BE << 0) +#define __HEAD_FLAG_PAGE_SIZE ((PAGE_SHIFT - 10) / 2) + +#define __HEAD_FLAGS ((__HEAD_FLAG_BE << 0) | \ + (__HEAD_FLAG_PAGE_SIZE << 1)) /* * These will output as part of the Image header, which should be little-endian |