diff options
Diffstat (limited to 'kernel/arch/xtensa/mm/init.c')
| -rw-r--r-- | kernel/arch/xtensa/mm/init.c | 430 |
1 files changed, 430 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/mm/init.c b/kernel/arch/xtensa/mm/init.c new file mode 100644 index 000000000..9a9a5935b --- /dev/null +++ b/kernel/arch/xtensa/mm/init.c @@ -0,0 +1,430 @@ +/* + * arch/xtensa/mm/init.c + * + * Derived from MIPS, PPC. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001 - 2005 Tensilica Inc. + * Copyright (C) 2014 Cadence Design Systems Inc. + * + * Chris Zankel <chris@zankel.net> + * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com> + * Marc Gauthier + * Kevin Chea + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/bootmem.h> +#include <linux/gfp.h> +#include <linux/highmem.h> +#include <linux/swap.h> +#include <linux/mman.h> +#include <linux/nodemask.h> +#include <linux/mm.h> + +#include <asm/bootparam.h> +#include <asm/page.h> +#include <asm/sections.h> +#include <asm/sysmem.h> + +struct sysmem_info sysmem __initdata; + +static void __init sysmem_dump(void) +{ + unsigned i; + + pr_debug("Sysmem:\n"); + for (i = 0; i < sysmem.nr_banks; ++i) + pr_debug(" 0x%08lx - 0x%08lx (%ldK)\n", + sysmem.bank[i].start, sysmem.bank[i].end, + (sysmem.bank[i].end - sysmem.bank[i].start) >> 10); +} + +/* + * Find bank with maximal .start such that bank.start <= start + */ +static inline struct meminfo * __init find_bank(unsigned long start) +{ + unsigned i; + struct meminfo *it = NULL; + + for (i = 0; i < sysmem.nr_banks; ++i) + if (sysmem.bank[i].start <= start) + it = sysmem.bank + i; + else + break; + return it; +} + +/* + * Move all memory banks starting at 'from' to a new place at 'to', + * adjust nr_banks accordingly. + * Both 'from' and 'to' must be inside the sysmem.bank. + * + * Returns: 0 (success), -ENOMEM (not enough space in the sysmem.bank). + */ +static int __init move_banks(struct meminfo *to, struct meminfo *from) +{ + unsigned n = sysmem.nr_banks - (from - sysmem.bank); + + if (to > from && to - from + sysmem.nr_banks > SYSMEM_BANKS_MAX) + return -ENOMEM; + if (to != from) + memmove(to, from, n * sizeof(struct meminfo)); + sysmem.nr_banks += to - from; + return 0; +} + +/* + * Add new bank to sysmem. Resulting sysmem is the union of bytes of the + * original sysmem and the new bank. + * + * Returns: 0 (success), < 0 (error) + */ +int __init add_sysmem_bank(unsigned long start, unsigned long end) +{ + unsigned i; + struct meminfo *it = NULL; + unsigned long sz; + unsigned long bank_sz = 0; + + if (start == end || + (start < end) != (PAGE_ALIGN(start) < (end & PAGE_MASK))) { + pr_warn("Ignoring small memory bank 0x%08lx size: %ld bytes\n", + start, end - start); + return -EINVAL; + } + + start = PAGE_ALIGN(start); + end &= PAGE_MASK; + sz = end - start; + + it = find_bank(start); + + if (it) + bank_sz = it->end - it->start; + + if (it && bank_sz >= start - it->start) { + if (end - it->start > bank_sz) + it->end = end; + else + return 0; + } else { + if (!it) + it = sysmem.bank; + else + ++it; + + if (it - sysmem.bank < sysmem.nr_banks && + it->start - start <= sz) { + it->start = start; + if (it->end - it->start < sz) + it->end = end; + else + return 0; + } else { + if (move_banks(it + 1, it) < 0) { + pr_warn("Ignoring memory bank 0x%08lx size %ld bytes\n", + start, end - start); + return -EINVAL; + } + it->start = start; + it->end = end; + return 0; + } + } + sz = it->end - it->start; + for (i = it + 1 - sysmem.bank; i < sysmem.nr_banks; ++i) + if (sysmem.bank[i].start - it->start <= sz) { + if (sz < sysmem.bank[i].end - it->start) + it->end = sysmem.bank[i].end; + } else { + break; + } + + move_banks(it + 1, sysmem.bank + i); + return 0; +} + +/* + * mem_reserve(start, end, must_exist) + * + * Reserve some memory from the memory pool. + * If must_exist is set and a part of the region being reserved does not exist + * memory map is not altered. + * + * Parameters: + * start Start of region, + * end End of region, + * must_exist Must exist in memory pool. + * + * Returns: + * 0 (success) + * < 0 (error) + */ + +int __init mem_reserve(unsigned long start, unsigned long end, int must_exist) +{ + struct meminfo *it; + struct meminfo *rm = NULL; + unsigned long sz; + unsigned long bank_sz = 0; + + start = start & PAGE_MASK; + end = PAGE_ALIGN(end); + sz = end - start; + if (!sz) + return -EINVAL; + + it = find_bank(start); + + if (it) + bank_sz = it->end - it->start; + + if ((!it || end - it->start > bank_sz) && must_exist) { + pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n", + start, end); + return -EINVAL; + } + + if (it && start - it->start <= bank_sz) { + if (start == it->start) { + if (end - it->start < bank_sz) { + it->start = end; + return 0; + } else { + rm = it; + } + } else { + it->end = start; + if (end - it->start < bank_sz) + return add_sysmem_bank(end, + it->start + bank_sz); + ++it; + } + } + + if (!it) + it = sysmem.bank; + + for (; it < sysmem.bank + sysmem.nr_banks; ++it) { + if (it->end - start <= sz) { + if (!rm) + rm = it; + } else { + if (it->start - start < sz) + it->start = end; + break; + } + } + + if (rm) + move_banks(rm, it); + + return 0; +} + + +/* + * Initialize the bootmem system and give it all low memory we have available. + */ + +void __init bootmem_init(void) +{ + unsigned long pfn; + unsigned long bootmap_start, bootmap_size; + int i; + + /* Reserve all memory below PLATFORM_DEFAULT_MEM_START, as memory + * accounting doesn't work for pages below that address. + * + * If PLATFORM_DEFAULT_MEM_START is zero reserve page at address 0: + * successfull allocations should never return NULL. + */ + if (PLATFORM_DEFAULT_MEM_START) + mem_reserve(0, PLATFORM_DEFAULT_MEM_START, 0); + else + mem_reserve(0, 1, 0); + + sysmem_dump(); + max_low_pfn = max_pfn = 0; + min_low_pfn = ~0; + + for (i=0; i < sysmem.nr_banks; i++) { + pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT; + if (pfn < min_low_pfn) + min_low_pfn = pfn; + pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT; + if (pfn > max_pfn) + max_pfn = pfn; + } + + if (min_low_pfn > max_pfn) + panic("No memory found!\n"); + + max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? + max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; + + /* Find an area to use for the bootmem bitmap. */ + + bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn); + bootmap_size <<= PAGE_SHIFT; + bootmap_start = ~0; + + for (i=0; i<sysmem.nr_banks; i++) + if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) { + bootmap_start = sysmem.bank[i].start; + break; + } + + if (bootmap_start == ~0UL) + panic("Cannot find %ld bytes for bootmap\n", bootmap_size); + + /* Reserve the bootmem bitmap area */ + + mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1); + bootmap_size = init_bootmem_node(NODE_DATA(0), + bootmap_start >> PAGE_SHIFT, + min_low_pfn, + max_low_pfn); + + /* Add all remaining memory pieces into the bootmem map */ + + for (i = 0; i < sysmem.nr_banks; i++) { + if (sysmem.bank[i].start >> PAGE_SHIFT < max_low_pfn) { + unsigned long end = min(max_low_pfn << PAGE_SHIFT, + sysmem.bank[i].end); + free_bootmem(sysmem.bank[i].start, + end - sysmem.bank[i].start); + } + } + +} + + +void __init zones_init(void) +{ + /* All pages are DMA-able, so we put them all in the DMA zone. */ + unsigned long zones_size[MAX_NR_ZONES] = { + [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET, +#ifdef CONFIG_HIGHMEM + [ZONE_HIGHMEM] = max_pfn - max_low_pfn, +#endif + }; + free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL); +} + +/* + * Initialize memory pages. + */ + +void __init mem_init(void) +{ +#ifdef CONFIG_HIGHMEM + unsigned long tmp; + + reset_all_zones_managed_pages(); + for (tmp = max_low_pfn; tmp < max_pfn; tmp++) + free_highmem_page(pfn_to_page(tmp)); +#endif + + max_mapnr = max_pfn - ARCH_PFN_OFFSET; + high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT); + + free_all_bootmem(); + + mem_init_print_info(NULL); + pr_info("virtual kernel memory layout:\n" +#ifdef CONFIG_HIGHMEM + " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n" + " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n" +#endif +#ifdef CONFIG_MMU + " vmalloc : 0x%08x - 0x%08x (%5u MB)\n" +#endif + " lowmem : 0x%08lx - 0x%08lx (%5lu MB)\n", +#ifdef CONFIG_HIGHMEM + PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE, + (LAST_PKMAP*PAGE_SIZE) >> 10, + FIXADDR_START, FIXADDR_TOP, + (FIXADDR_TOP - FIXADDR_START) >> 10, +#endif +#ifdef CONFIG_MMU + VMALLOC_START, VMALLOC_END, + (VMALLOC_END - VMALLOC_START) >> 20, + PAGE_OFFSET, PAGE_OFFSET + + (max_low_pfn - min_low_pfn) * PAGE_SIZE, +#else + min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE, +#endif + ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20); +} + +#ifdef CONFIG_BLK_DEV_INITRD +extern int initrd_is_mapped; + +void free_initrd_mem(unsigned long start, unsigned long end) +{ + if (initrd_is_mapped) + free_reserved_area((void *)start, (void *)end, -1, "initrd"); +} +#endif + +void free_initmem(void) +{ + free_initmem_default(-1); +} + +static void __init parse_memmap_one(char *p) +{ + char *oldp; + unsigned long start_at, mem_size; + + if (!p) + return; + + oldp = p; + mem_size = memparse(p, &p); + if (p == oldp) + return; + + switch (*p) { + case '@': + start_at = memparse(p + 1, &p); + add_sysmem_bank(start_at, start_at + mem_size); + break; + + case '$': + start_at = memparse(p + 1, &p); + mem_reserve(start_at, start_at + mem_size, 0); + break; + + case 0: + mem_reserve(mem_size, 0, 0); + break; + + default: + pr_warn("Unrecognized memmap syntax: %s\n", p); + break; + } +} + +static int __init parse_memmap_opt(char *str) +{ + while (str) { + char *k = strchr(str, ','); + + if (k) + *k++ = 0; + + parse_memmap_one(str); + str = k; + } + + return 0; +} +early_param("memmap", parse_memmap_opt); |