From 4f04d8f00545110a0e525ae2fb62ab38cb417236 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 5 Mar 2012 11:49:27 +0000 Subject: 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 Signed-off-by: Catalin Marinas Acked-by: Tony Lindgren Acked-by: Nicolas Pitre Acked-by: Olof Johansson Acked-by: Santosh Shilimkar Acked-by: Arnd Bergmann --- arch/arm64/include/asm/sparsemem.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 arch/arm64/include/asm/sparsemem.h (limited to 'arch/arm64/include/asm/sparsemem.h') diff --git a/arch/arm64/include/asm/sparsemem.h b/arch/arm64/include/asm/sparsemem.h new file mode 100644 index 000000000000..1be62bcb9d47 --- /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 . + */ +#ifndef __ASM_SPARSEMEM_H +#define __ASM_SPARSEMEM_H + +#ifdef CONFIG_SPARSEMEM +#define MAX_PHYSMEM_BITS 40 +#define SECTION_SIZE_BITS 30 +#endif + +#endif -- cgit v1.2.3-59-g8ed1b