Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759955AbZCBQ7p (ORCPT ); Mon, 2 Mar 2009 11:59:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758528AbZCBQ6F (ORCPT ); Mon, 2 Mar 2009 11:58:05 -0500 Received: from mx1.emlix.com ([193.175.82.87]:36350 "EHLO mx1.emlix.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755824AbZCBQ6B (ORCPT ); Mon, 2 Mar 2009 11:58:01 -0500 References: <20090302164257.477296438@emlix.com> User-Agent: quilt/0.46-1 Date: Mon, 02 Mar 2009 17:43:04 +0100 From: Johannes Weiner To: Chris Zankel Cc: linux-kernel@vger.kernel.org Subject: [patch 7/7] xtensa: cope with ram beginning at higher addresses Content-Disposition: inline; filename=xtensa-cope-with-ram-beginning-at-higher-addresses.patch Message-Id: Organization: emlix gmbh, Goettingen, Germany Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3505 Lines: 104 The current assumption of the memory code is that the first RAM PFN in the system is 0. Adjust the relevant code to play well with setups where memory starts at higher addresses, indicated by PLATFORM_DEFAULT_MEM_START. The new memory model looks like this: +----------+--+----------------------+----------------+ | | | | | | | | RAM | | | | | | | +----------+--+----------------------+----------------+ | | | | | +- PFN 0 | +- min_low_pfn +- max_low_pfn +- max_pfn | +- ARCH_PFN_OFFSET +- PLATFORM_DEFAULT_MEM_START >> PAGE_SIZE The memory map contains pages starting from pfn ARCH_PFN_OFFSET up to max_low_pfn. The only zone used right now will span exactly the same region. Usually, ARCH_PFN_OFFSET and min_low_pfn are the same value. Handle them separately for robustness. Gapping pages will be in the memory map but marked as reserved and won't be touched. Signed-off-by: Johannes Weiner --- arch/xtensa/include/asm/page.h | 5 ++++- arch/xtensa/mm/init.c | 10 +++++----- 2 files changed, 9 insertions(+), 6 deletions(-) --- a/arch/xtensa/include/asm/page.h +++ b/arch/xtensa/include/asm/page.h @@ -14,6 +14,7 @@ #include #include #include +#include /* * Fixed TLB translations in the processor. @@ -150,9 +151,11 @@ extern void copy_user_page(void*, void*, * addresses. */ +#define ARCH_PFN_OFFSET (PLATFORM_DEFAULT_MEM_START >> PAGE_SHIFT) + #define __pa(x) ((unsigned long) (x) - PAGE_OFFSET) #define __va(x) ((void *)((unsigned long) (x) + PAGE_OFFSET)) -#define pfn_valid(pfn) ((unsigned long)pfn < max_mapnr) +#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) #ifdef CONFIG_DISCONTIGMEM # error CONFIG_DISCONTIGMEM not supported #endif --- a/arch/xtensa/mm/init.c +++ b/arch/xtensa/mm/init.c @@ -167,7 +167,7 @@ void __init paging_init(void) /* All pages are DMA-able, so we put them all in the DMA zone. */ - zones_size[ZONE_DMA] = max_low_pfn; + zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET; for (i = 1; i < MAX_NR_ZONES; i++) zones_size[i] = 0; @@ -179,7 +179,7 @@ void __init paging_init(void) memset(swapper_pg_dir, 0, PAGE_SIZE); - free_area_init(zones_size); + free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); } /* @@ -220,8 +220,8 @@ void __init mem_init(void) unsigned long codesize, reservedpages, datasize, initsize; unsigned long highmemsize, tmp, ram; - max_mapnr = num_physpages = max_low_pfn; - high_memory = (void *) __va(max_mapnr << PAGE_SHIFT); + max_mapnr = num_physpages = max_low_pfn - ARCH_PFN_OFFSET; + high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT); highmemsize = 0; #ifdef CONFIG_HIGHMEM @@ -231,7 +231,7 @@ void __init mem_init(void) totalram_pages += free_all_bootmem(); reservedpages = ram = 0; - for (tmp = 0; tmp < max_low_pfn; tmp++) { + for (tmp = 0; tmp < max_mapnr; tmp++) { ram++; if (PageReserved(mem_map+tmp)) reservedpages++; -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/