diff options
Diffstat (limited to 'kernel/arch/arc/mm/init.c')
| -rw-r--r-- | kernel/arch/arc/mm/init.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/kernel/arch/arc/mm/init.c b/kernel/arch/arc/mm/init.c new file mode 100644 index 000000000..d44eedd8c --- /dev/null +++ b/kernel/arch/arc/mm/init.c @@ -0,0 +1,155 @@ +/* + * 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_BLK_DEV_INITRD +#include <linux/initrd.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 = 0x20000000; /* some default */ + +/* 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); + +void __init early_init_dt_add_memory_arch(u64 base, u64 size) +{ + arc_mem_sz = size & PAGE_MASK; + pr_info("Memory size set via devicetree %ldM\n", TO_MB(arc_mem_sz)); +} + +#ifdef CONFIG_BLK_DEV_INITRD +static int __init early_initrd(char *p) +{ + unsigned long start, size; + char *endp; + + start = memparse(p, &endp); + if (*endp == ',') { + size = memparse(endp + 1, NULL); + + initrd_start = (unsigned long)__va(start); + initrd_end = (unsigned long)__va(start + size); + } + return 0; +} +early_param("initrd", early_initrd); +#endif + +/* + * 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]; + 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 given and/or + * DT has memory node. Each causes an update to @arc_mem_sz + * and we finally add memory one here + */ + 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 = ARCH_PFN_OFFSET; + + /* Last usable page of low mem (no HIGHMEM yet for ARC port) */ + max_low_pfn = max_pfn = PFN_DOWN(end_mem); + + max_mapnr = max_low_pfn - min_low_pfn; + + /*------------- reserve kernel image -----------------------*/ + memblock_reserve(CONFIG_LINUX_LINK_BASE, + __pa(_end) - CONFIG_LINUX_LINK_BASE); + +#ifdef CONFIG_BLK_DEV_INITRD + /*------------- reserve initrd image -----------------------*/ + if (initrd_start) + memblock_reserve(__pa(initrd_start), initrd_end - initrd_start); +#endif + + memblock_dump_all(); + + /*-------------- node setup --------------------------------*/ + memset(zones_size, 0, sizeof(zones_size)); + zones_size[ZONE_NORMAL] = max_mapnr; + + /* + * 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 */ + + high_memory = (void *)end_mem; +} + +/* + * mem_init - initializes memory + * + * Frees up bootmem + * Calculates and displays memory available/used + */ +void __init mem_init(void) +{ + free_all_bootmem(); + mem_init_print_info(NULL); +} + +/* + * free_initmem: Free all the __init memory. + */ +void __init_refok free_initmem(void) +{ + free_initmem_default(-1); +} + +#ifdef CONFIG_BLK_DEV_INITRD +void __init free_initrd_mem(unsigned long start, unsigned long end) +{ + free_reserved_area((void *)start, (void *)end, -1, "initrd"); +} +#endif |