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author | Vineet Gupta <vgupta@synopsys.com> | 2013-01-18 10:42:20 +0100 |
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committer | Vineet Gupta <vgupta@synopsys.com> | 2013-02-15 18:45:54 +0100 |
commit | c121c5063c0674fad6811f0b0d86ec3bc6eecbbd (patch) | |
tree | 956c6f18fcf72d3e20a86168669237ecdabd8a13 /arch/arc/mm | |
parent | ARC: I/O and DMA Mappings (diff) | |
download | linux-c121c5063c0674fad6811f0b0d86ec3bc6eecbbd.tar.xz linux-c121c5063c0674fad6811f0b0d86ec3bc6eecbbd.zip |
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arc/mm')
-rw-r--r-- | arch/arc/mm/init.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c new file mode 100644 index 000000000000..63da3478521f --- /dev/null +++ b/arch/arc/mm/init.c @@ -0,0 +1,171 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/bootmem.h> +#include <linux/memblock.h> +#ifdef CONFIG_BLOCK_DEV_RAM +#include <linux/blk.h> +#endif +#include <linux/swap.h> +#include <linux/module.h> +#include <asm/page.h> +#include <asm/pgalloc.h> +#include <asm/sections.h> +#include <asm/arcregs.h> + +pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE); +char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE); +EXPORT_SYMBOL(empty_zero_page); + +/* Default tot mem from .config */ +static unsigned long arc_mem_sz = CONFIG_ARC_PLAT_SDRAM_SIZE; + +/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */ +static int __init setup_mem_sz(char *str) +{ + arc_mem_sz = memparse(str, NULL) & PAGE_MASK; + + /* early console might not be setup yet - it will show up later */ + pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(arc_mem_sz)); + + return 0; +} +early_param("mem", setup_mem_sz); + +/* + * First memory setup routine called from setup_arch() + * 1. setup swapper's mm @init_mm + * 2. Count the pages we have and setup bootmem allocator + * 3. zone setup + */ +void __init setup_arch_memory(void) +{ + unsigned long zones_size[MAX_NR_ZONES] = { 0, 0 }; + unsigned long end_mem = CONFIG_LINUX_LINK_BASE + arc_mem_sz; + + init_mm.start_code = (unsigned long)_text; + init_mm.end_code = (unsigned long)_etext; + init_mm.end_data = (unsigned long)_edata; + init_mm.brk = (unsigned long)_end; + + /* + * We do it here, so that memory is correctly instantiated + * even if "mem=xxx" cmline over-ride is not given + */ + memblock_add(CONFIG_LINUX_LINK_BASE, arc_mem_sz); + + /*------------- externs in mm need setting up ---------------*/ + + /* first page of system - kernel .vector starts here */ + min_low_pfn = PFN_DOWN(CONFIG_LINUX_LINK_BASE); + + /* Last usable page of low mem (no HIGHMEM yet for ARC port) */ + max_low_pfn = max_pfn = PFN_DOWN(end_mem); + + max_mapnr = num_physpages = max_low_pfn - min_low_pfn; + + /*------------- reserve kernel image -----------------------*/ + memblock_reserve(CONFIG_LINUX_LINK_BASE, + __pa(_end) - CONFIG_LINUX_LINK_BASE); + + memblock_dump_all(); + + /*-------------- node setup --------------------------------*/ + memset(zones_size, 0, sizeof(zones_size)); + zones_size[ZONE_NORMAL] = num_physpages; + + /* + * We can't use the helper free_area_init(zones[]) because it uses + * PAGE_OFFSET to compute the @min_low_pfn which would be wrong + * when our kernel doesn't start at PAGE_OFFSET, i.e. + * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE + */ + free_area_init_node(0, /* node-id */ + zones_size, /* num pages per zone */ + min_low_pfn, /* first pfn of node */ + NULL); /* NO holes */ +} + +/* + * mem_init - initializes memory + * + * Frees up bootmem + * Calculates and displays memory available/used + */ +void __init mem_init(void) +{ + int codesize, datasize, initsize, reserved_pages, free_pages; + int tmp; + + high_memory = (void *)(CONFIG_LINUX_LINK_BASE + arc_mem_sz); + + totalram_pages = free_all_bootmem(); + + /* count all reserved pages [kernel code/data/mem_map..] */ + reserved_pages = 0; + for (tmp = 0; tmp < max_mapnr; tmp++) + if (PageReserved(mem_map + tmp)) + reserved_pages++; + + /* XXX: nr_free_pages() is equivalent */ + free_pages = max_mapnr - reserved_pages; + + /* + * For the purpose of display below, split the "reserve mem" + * kernel code/data is already shown explicitly, + * Show any other reservations (mem_map[ ] et al) + */ + reserved_pages -= (((unsigned int)_end - CONFIG_LINUX_LINK_BASE) >> + PAGE_SHIFT); + + codesize = _etext - _text; + datasize = _end - _etext; + initsize = __init_end - __init_begin; + + pr_info("Memory Available: %dM / %ldM (%dK code, %dK data, %dK init, %dK reserv)\n", + PAGES_TO_MB(free_pages), + TO_MB(arc_mem_sz), + TO_KB(codesize), TO_KB(datasize), TO_KB(initsize), + PAGES_TO_KB(reserved_pages)); +} + +static void __init free_init_pages(const char *what, unsigned long begin, + unsigned long end) +{ + unsigned long addr; + + pr_info("Freeing %s: %ldk [%lx] to [%lx]\n", + what, TO_KB(end - begin), begin, end); + + /* need to check that the page we free is not a partial page */ + for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) { + ClearPageReserved(virt_to_page(addr)); + init_page_count(virt_to_page(addr)); + free_page(addr); + totalram_pages++; + } +} + +/* + * free_initmem: Free all the __init memory. + */ +void __init_refok free_initmem(void) +{ + free_init_pages("unused kernel memory", + (unsigned long)__init_begin, + (unsigned long)__init_end); +} + +#ifdef CONFIG_BLK_DEV_INITRD +void __init free_initrd_mem(unsigned long start, unsigned long end) +{ + free_init_pages("initrd memory", start, end); +} +#endif |