diff options
| author | Catalin Marinas <catalin.marinas@arm.com> | 2012-03-05 11:49:27 +0000 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2012-09-17 13:41:56 +0100 |
| commit | 4f04d8f00545110a0e525ae2fb62ab38cb417236 (patch) | |
| tree | 021c6ff01a972de47341959b0bd0888775c9ed7b /arch/arm64/include/asm/sparsemem.h | |
| parent | 60ffc30d5652810dd34ea2eec41504222f5d5791 (diff) | |
arm64: MMU definitions
The virtual memory layout is described in
Documentation/arm64/memory.txt. This patch adds the MMU definitions for
the 4KB and 64KB translation table configurations. The SECTION_SIZE is
2MB with 4KB page and 512MB with 64KB page configuration.
PHYS_OFFSET is calculated at run-time and stored in a variable (no
run-time code patching at this stage).
On the current implementation, both user and kernel address spaces are
512G (39-bit) each with a maximum of 256G for the RAM linear mapping.
Linux uses 3 levels of translation tables with the 4K page configuration
and 2 levels with the 64K configuration. Extending the memory space
beyond 39-bit with the 4K pages or 42-bit with 64K pages requires an
additional level of translation tables.
The SPARSEMEM configuration is global to all AArch64 platforms and
allows for 1GB sections with SPARSEMEM_VMEMMAP enabled by default.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm64/include/asm/sparsemem.h')
| -rw-r--r-- | arch/arm64/include/asm/sparsemem.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/sparsemem.h b/arch/arm64/include/asm/sparsemem.h new file mode 100644 index 00000000000..1be62bcb9d4 --- /dev/null +++ b/arch/arm64/include/asm/sparsemem.h @@ -0,0 +1,24 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_SPARSEMEM_H +#define __ASM_SPARSEMEM_H + +#ifdef CONFIG_SPARSEMEM +#define MAX_PHYSMEM_BITS 40 +#define SECTION_SIZE_BITS 30 +#endif + +#endif |