diff options
Diffstat (limited to 'arch/avr32/mm/init.c')
-rw-r--r-- | arch/avr32/mm/init.c | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/arch/avr32/mm/init.c b/arch/avr32/mm/init.c new file mode 100644 index 0000000..3e6c410 --- /dev/null +++ b/arch/avr32/mm/init.c @@ -0,0 +1,480 @@ +/* + * Copyright (C) 2004-2006 Atmel Corporation + * + * 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/swap.h> +#include <linux/init.h> +#include <linux/initrd.h> +#include <linux/mmzone.h> +#include <linux/bootmem.h> +#include <linux/pagemap.h> +#include <linux/pfn.h> +#include <linux/nodemask.h> + +#include <asm/page.h> +#include <asm/mmu_context.h> +#include <asm/tlb.h> +#include <asm/io.h> +#include <asm/dma.h> +#include <asm/setup.h> +#include <asm/sections.h> + +DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); + +pgd_t swapper_pg_dir[PTRS_PER_PGD]; + +struct page *empty_zero_page; + +/* + * Cache of MMU context last used. + */ +unsigned long mmu_context_cache = NO_CONTEXT; + +#define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT) +#define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn) + +void show_mem(void) +{ + int total = 0, reserved = 0, cached = 0; + int slab = 0, free = 0, shared = 0; + pg_data_t *pgdat; + + printk("Mem-info:\n"); + show_free_areas(); + + for_each_online_pgdat(pgdat) { + struct page *page, *end; + + page = pgdat->node_mem_map; + end = page + pgdat->node_spanned_pages; + + do { + total++; + if (PageReserved(page)) + reserved++; + else if (PageSwapCache(page)) + cached++; + else if (PageSlab(page)) + slab++; + else if (!page_count(page)) + free++; + else + shared += page_count(page) - 1; + page++; + } while (page < end); + } + + printk ("%d pages of RAM\n", total); + printk ("%d free pages\n", free); + printk ("%d reserved pages\n", reserved); + printk ("%d slab pages\n", slab); + printk ("%d pages shared\n", shared); + printk ("%d pages swap cached\n", cached); +} + +static void __init print_memory_map(const char *what, + struct tag_mem_range *mem) +{ + printk ("%s:\n", what); + for (; mem; mem = mem->next) { + printk (" %08lx - %08lx\n", + (unsigned long)mem->addr, + (unsigned long)(mem->addr + mem->size)); + } +} + +#define MAX_LOWMEM HIGHMEM_START +#define MAX_LOWMEM_PFN PFN_DOWN(MAX_LOWMEM) + +/* + * Sort a list of memory regions in-place by ascending address. + * + * We're using bubble sort because we only have singly linked lists + * with few elements. + */ +static void __init sort_mem_list(struct tag_mem_range **pmem) +{ + int done; + struct tag_mem_range **a, **b; + + if (!*pmem) + return; + + do { + done = 1; + a = pmem, b = &(*pmem)->next; + while (*b) { + if ((*a)->addr > (*b)->addr) { + struct tag_mem_range *tmp; + tmp = (*b)->next; + (*b)->next = *a; + *a = *b; + *b = tmp; + done = 0; + } + a = &(*a)->next; + b = &(*a)->next; + } + } while (!done); +} + +/* + * Find a free memory region large enough for storing the + * bootmem bitmap. + */ +static unsigned long __init +find_bootmap_pfn(const struct tag_mem_range *mem) +{ + unsigned long bootmap_pages, bootmap_len; + unsigned long node_pages = PFN_UP(mem->size); + unsigned long bootmap_addr = mem->addr; + struct tag_mem_range *reserved = mem_reserved; + struct tag_mem_range *ramdisk = mem_ramdisk; + unsigned long kern_start = virt_to_phys(_stext); + unsigned long kern_end = virt_to_phys(_end); + + bootmap_pages = bootmem_bootmap_pages(node_pages); + bootmap_len = bootmap_pages << PAGE_SHIFT; + + /* + * Find a large enough region without reserved pages for + * storing the bootmem bitmap. We can take advantage of the + * fact that all lists have been sorted. + * + * We have to check explicitly reserved regions as well as the + * kernel image and any RAMDISK images... + * + * Oh, and we have to make sure we don't overwrite the taglist + * since we're going to use it until the bootmem allocator is + * fully up and running. + */ + while (1) { + if ((bootmap_addr < kern_end) && + ((bootmap_addr + bootmap_len) > kern_start)) + bootmap_addr = kern_end; + + while (reserved && + (bootmap_addr >= (reserved->addr + reserved->size))) + reserved = reserved->next; + + if (reserved && + ((bootmap_addr + bootmap_len) >= reserved->addr)) { + bootmap_addr = reserved->addr + reserved->size; + continue; + } + + while (ramdisk && + (bootmap_addr >= (ramdisk->addr + ramdisk->size))) + ramdisk = ramdisk->next; + + if (!ramdisk || + ((bootmap_addr + bootmap_len) < ramdisk->addr)) + break; + + bootmap_addr = ramdisk->addr + ramdisk->size; + } + + if ((PFN_UP(bootmap_addr) + bootmap_len) >= (mem->addr + mem->size)) + return ~0UL; + + return PFN_UP(bootmap_addr); +} + +void __init setup_bootmem(void) +{ + unsigned bootmap_size; + unsigned long first_pfn, bootmap_pfn, pages; + unsigned long max_pfn, max_low_pfn; + unsigned long kern_start = virt_to_phys(_stext); + unsigned long kern_end = virt_to_phys(_end); + unsigned node = 0; + struct tag_mem_range *bank, *res; + + sort_mem_list(&mem_phys); + sort_mem_list(&mem_reserved); + + print_memory_map("Physical memory", mem_phys); + print_memory_map("Reserved memory", mem_reserved); + + nodes_clear(node_online_map); + + if (mem_ramdisk) { +#ifdef CONFIG_BLK_DEV_INITRD + initrd_start = __va(mem_ramdisk->addr); + initrd_end = initrd_start + mem_ramdisk->size; + + print_memory_map("RAMDISK images", mem_ramdisk); + if (mem_ramdisk->next) + printk(KERN_WARNING + "Warning: Only the first RAMDISK image " + "will be used\n"); + sort_mem_list(&mem_ramdisk); +#else + printk(KERN_WARNING "RAM disk image present, but " + "no initrd support in kernel!\n"); +#endif + } + + if (mem_phys->next) + printk(KERN_WARNING "Only using first memory bank\n"); + + for (bank = mem_phys; bank; bank = NULL) { + first_pfn = PFN_UP(bank->addr); + max_low_pfn = max_pfn = PFN_DOWN(bank->addr + bank->size); + bootmap_pfn = find_bootmap_pfn(bank); + if (bootmap_pfn > max_pfn) + panic("No space for bootmem bitmap!\n"); + + if (max_low_pfn > MAX_LOWMEM_PFN) { + max_low_pfn = MAX_LOWMEM_PFN; +#ifndef CONFIG_HIGHMEM + /* + * Lowmem is memory that can be addressed + * directly through P1/P2 + */ + printk(KERN_WARNING + "Node %u: Only %ld MiB of memory will be used.\n", + node, MAX_LOWMEM >> 20); + printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n"); +#else +#error HIGHMEM is not supported by AVR32 yet +#endif + } + + /* Initialize the boot-time allocator with low memory only. */ + bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn, + first_pfn, max_low_pfn); + + printk("Node %u: bdata = %p, bdata->node_bootmem_map = %p\n", + node, NODE_DATA(node)->bdata, + NODE_DATA(node)->bdata->node_bootmem_map); + + /* + * Register fully available RAM pages with the bootmem + * allocator. + */ + pages = max_low_pfn - first_pfn; + free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn), + PFN_PHYS(pages)); + + /* + * Reserve space for the kernel image (if present in + * this node)... + */ + if ((kern_start >= PFN_PHYS(first_pfn)) && + (kern_start < PFN_PHYS(max_pfn))) { + printk("Node %u: Kernel image %08lx - %08lx\n", + node, kern_start, kern_end); + reserve_bootmem_node(NODE_DATA(node), kern_start, + kern_end - kern_start); + } + + /* ...the bootmem bitmap... */ + reserve_bootmem_node(NODE_DATA(node), + PFN_PHYS(bootmap_pfn), + bootmap_size); + + /* ...any RAMDISK images... */ + for (res = mem_ramdisk; res; res = res->next) { + if (res->addr > PFN_PHYS(max_pfn)) + break; + + if (res->addr >= PFN_PHYS(first_pfn)) { + printk("Node %u: RAMDISK %08lx - %08lx\n", + node, + (unsigned long)res->addr, + (unsigned long)(res->addr + res->size)); + reserve_bootmem_node(NODE_DATA(node), + res->addr, res->size); + } + } + + /* ...and any other reserved regions. */ + for (res = mem_reserved; res; res = res->next) { + if (res->addr > PFN_PHYS(max_pfn)) + break; + + if (res->addr >= PFN_PHYS(first_pfn)) { + printk("Node %u: Reserved %08lx - %08lx\n", + node, + (unsigned long)res->addr, + (unsigned long)(res->addr + res->size)); + reserve_bootmem_node(NODE_DATA(node), + res->addr, res->size); + } + } + + node_set_online(node); + } +} + +/* + * paging_init() sets up the page tables + * + * This routine also unmaps the page at virtual kernel address 0, so + * that we can trap those pesky NULL-reference errors in the kernel. + */ +void __init paging_init(void) +{ + extern unsigned long _evba; + void *zero_page; + int nid; + + /* + * Make sure we can handle exceptions before enabling + * paging. Not that we should ever _get_ any exceptions this + * early, but you never know... + */ + printk("Exception vectors start at %p\n", &_evba); + sysreg_write(EVBA, (unsigned long)&_evba); + + /* + * Since we are ready to handle exceptions now, we should let + * the CPU generate them... + */ + __asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT)); + + /* + * Allocate the zero page. The allocator will panic if it + * can't satisfy the request, so no need to check. + */ + zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0), + PAGE_SIZE); + + { + pgd_t *pg_dir; + int i; + + pg_dir = swapper_pg_dir; + sysreg_write(PTBR, (unsigned long)pg_dir); + + for (i = 0; i < PTRS_PER_PGD; i++) + pgd_val(pg_dir[i]) = 0; + + enable_mmu(); + printk ("CPU: Paging enabled\n"); + } + + for_each_online_node(nid) { + pg_data_t *pgdat = NODE_DATA(nid); + unsigned long zones_size[MAX_NR_ZONES]; + unsigned long low, start_pfn; + + start_pfn = pgdat->bdata->node_boot_start; + start_pfn >>= PAGE_SHIFT; + low = pgdat->bdata->node_low_pfn; + + memset(zones_size, 0, sizeof(zones_size)); + zones_size[ZONE_NORMAL] = low - start_pfn; + + printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n", + nid, start_pfn, low); + + free_area_init_node(nid, pgdat, zones_size, start_pfn, NULL); + + printk("Node %u: mem_map starts at %p\n", + pgdat->node_id, pgdat->node_mem_map); + } + + mem_map = NODE_DATA(0)->node_mem_map; + + memset(zero_page, 0, PAGE_SIZE); + empty_zero_page = virt_to_page(zero_page); + flush_dcache_page(empty_zero_page); +} + +void __init mem_init(void) +{ + int codesize, reservedpages, datasize, initsize; + int nid, i; + + reservedpages = 0; + high_memory = NULL; + + /* this will put all low memory onto the freelists */ + for_each_online_node(nid) { + pg_data_t *pgdat = NODE_DATA(nid); + unsigned long node_pages = 0; + void *node_high_memory; + + num_physpages += pgdat->node_present_pages; + + if (pgdat->node_spanned_pages != 0) + node_pages = free_all_bootmem_node(pgdat); + + totalram_pages += node_pages; + + for (i = 0; i < node_pages; i++) + if (PageReserved(pgdat->node_mem_map + i)) + reservedpages++; + + node_high_memory = (void *)((pgdat->node_start_pfn + + pgdat->node_spanned_pages) + << PAGE_SHIFT); + if (node_high_memory > high_memory) + high_memory = node_high_memory; + } + + max_mapnr = MAP_NR(high_memory); + + codesize = (unsigned long)_etext - (unsigned long)_text; + datasize = (unsigned long)_edata - (unsigned long)_data; + initsize = (unsigned long)__init_end - (unsigned long)__init_begin; + + printk ("Memory: %luk/%luk available (%dk kernel code, " + "%dk reserved, %dk data, %dk init)\n", + (unsigned long)nr_free_pages() << (PAGE_SHIFT - 10), + totalram_pages << (PAGE_SHIFT - 10), + codesize >> 10, + reservedpages << (PAGE_SHIFT - 10), + datasize >> 10, + initsize >> 10); +} + +static inline void free_area(unsigned long addr, unsigned long end, char *s) +{ + unsigned int size = (end - addr) >> 10; + + for (; addr < end; addr += PAGE_SIZE) { + struct page *page = virt_to_page(addr); + ClearPageReserved(page); + init_page_count(page); + free_page(addr); + totalram_pages++; + } + + if (size && s) + printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n", + s, size, end - (size << 10), end); +} + +void free_initmem(void) +{ + free_area((unsigned long)__init_begin, (unsigned long)__init_end, + "init"); +} + +#ifdef CONFIG_BLK_DEV_INITRD + +static int keep_initrd; + +void free_initrd_mem(unsigned long start, unsigned long end) +{ + if (!keep_initrd) + free_area(start, end, "initrd"); +} + +static int __init keepinitrd_setup(char *__unused) +{ + keep_initrd = 1; + return 1; +} + +__setup("keepinitrd", keepinitrd_setup); +#endif |