1 files changed, 621 insertions, 0 deletions

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
new file mode 100644
index 000000000000..41156c5370f7
--- /dev/null
+++ b/arch/arm/mm/init.c
@@ -0,0 +1,621 @@
+/*
+ *  linux/arch/arm/mm/init.c
+ *
+ *  Copyright (C) 1995-2002 Russell King
+ *
+ * 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/config.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/swap.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/mman.h>
+#include <linux/nodemask.h>
+#include <linux/initrd.h>
+
+#include <asm/mach-types.h>
+#include <asm/hardware.h>
+#include <asm/setup.h>
+#include <asm/tlb.h>
+
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#define TABLE_SIZE      (2 * PTRS_PER_PTE * sizeof(pte_t))
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern void _stext, _text, _etext, __data_start, _end, __init_begin, __init_end;
+extern unsigned long phys_initrd_start;
+extern unsigned long phys_initrd_size;
+
+/*
+ * The sole use of this is to pass memory configuration
+ * data from paging_init to mem_init.
+ */
+static struct meminfo meminfo __initdata = { 0, };
+
+/*
+ * empty_zero_page is a special page that is used for
+ * zero-initialized data and COW.
+ */
+struct page *empty_zero_page;
+
+void show_mem(void)
+{
+        int free = 0, total = 0, reserved = 0;
+        int shared = 0, cached = 0, slab = 0, node;
+
+        printk("Mem-info:\n");
+        show_free_areas();
+        printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+
+        for_each_online_node(node) {
+                struct page *page, *end;
+
+                page = NODE_MEM_MAP(node);
+                end  = page + NODE_DATA(node)->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);
+}
+
+struct node_info {
+        unsigned int start;
+        unsigned int end;
+        int bootmap_pages;
+};
+
+#define O_PFN_DOWN(x)   ((x) >> PAGE_SHIFT)
+#define V_PFN_DOWN(x)   O_PFN_DOWN(__pa(x))
+
+#define O_PFN_UP(x)     (PAGE_ALIGN(x) >> PAGE_SHIFT)
+#define V_PFN_UP(x)     O_PFN_UP(__pa(x))
+
+#define PFN_SIZE(x)     ((x) >> PAGE_SHIFT)
+#define PFN_RANGE(s,e)  PFN_SIZE(PAGE_ALIGN((unsigned long)(e)) - \
+                                (((unsigned long)(s)) & PAGE_MASK))
+
+/*
+ * FIXME: We really want to avoid allocating the bootmap bitmap
+ * over the top of the initrd.  Hopefully, this is located towards
+ * the start of a bank, so if we allocate the bootmap bitmap at
+ * the end, we won't clash.
+ */
+static unsigned int __init
+find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
+{
+        unsigned int start_pfn, bank, bootmap_pfn;
+
+        start_pfn   = V_PFN_UP(&_end);
+        bootmap_pfn = 0;
+
+        for (bank = 0; bank < mi->nr_banks; bank ++) {
+                unsigned int start, end;
+
+                if (mi->bank[bank].node != node)
+                        continue;
+
+                start = O_PFN_UP(mi->bank[bank].start);
+                end   = O_PFN_DOWN(mi->bank[bank].size +
+                                   mi->bank[bank].start);
+
+                if (end < start_pfn)
+                        continue;
+
+                if (start < start_pfn)
+                        start = start_pfn;
+
+                if (end <= start)
+                        continue;
+
+                if (end - start >= bootmap_pages) {
+                        bootmap_pfn = start;
+                        break;
+                }
+        }
+
+        if (bootmap_pfn == 0)
+                BUG();
+
+        return bootmap_pfn;
+}
+
+/*
+ * Scan the memory info structure and pull out:
+ *  - the end of memory
+ *  - the number of nodes
+ *  - the pfn range of each node
+ *  - the number of bootmem bitmap pages
+ */
+static unsigned int __init
+find_memend_and_nodes(struct meminfo *mi, struct node_info *np)
+{
+        unsigned int i, bootmem_pages = 0, memend_pfn = 0;
+
+        for (i = 0; i < MAX_NUMNODES; i++) {
+                np[i].start = -1U;
+                np[i].end = 0;
+                np[i].bootmap_pages = 0;
+        }
+
+        for (i = 0; i < mi->nr_banks; i++) {
+                unsigned long start, end;
+                int node;
+
+                if (mi->bank[i].size == 0) {
+                        /*
+                         * Mark this bank with an invalid node number
+                         */
+                        mi->bank[i].node = -1;
+                        continue;
+                }
+
+                node = mi->bank[i].node;
+
+                /*
+                 * Make sure we haven't exceeded the maximum number of nodes
+                 * that we have in this configuration.  If we have, we're in
+                 * trouble.  (maybe we ought to limit, instead of bugging?)
+                 */
+                if (node >= MAX_NUMNODES)
+                        BUG();
+                node_set_online(node);
+
+                /*
+                 * Get the start and end pfns for this bank
+                 */
+                start = O_PFN_UP(mi->bank[i].start);
+                end   = O_PFN_DOWN(mi->bank[i].start + mi->bank[i].size);
+
+                if (np[node].start > start)
+                        np[node].start = start;
+
+                if (np[node].end < end)
+                        np[node].end = end;
+
+                if (memend_pfn < end)
+                        memend_pfn = end;
+        }
+
+        /*
+         * Calculate the number of pages we require to
+         * store the bootmem bitmaps.
+         */
+        for_each_online_node(i) {
+                if (np[i].end == 0)
+                        continue;
+
+                np[i].bootmap_pages = bootmem_bootmap_pages(np[i].end -
+                                                            np[i].start);
+                bootmem_pages += np[i].bootmap_pages;
+        }
+
+        high_memory = __va(memend_pfn << PAGE_SHIFT);
+
+        /*
+         * This doesn't seem to be used by the Linux memory
+         * manager any more.  If we can get rid of it, we
+         * also get rid of some of the stuff above as well.
+         */
+        max_low_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
+        max_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
+
+        return bootmem_pages;
+}
+
+static int __init check_initrd(struct meminfo *mi)
+{
+        int initrd_node = -2;
+#ifdef CONFIG_BLK_DEV_INITRD
+        unsigned long end = phys_initrd_start + phys_initrd_size;
+
+        /*
+         * Make sure that the initrd is within a valid area of
+         * memory.
+         */
+        if (phys_initrd_size) {
+                unsigned int i;
+
+                initrd_node = -1;
+
+                for (i = 0; i < mi->nr_banks; i++) {
+                        unsigned long bank_end;
+
+                        bank_end = mi->bank[i].start + mi->bank[i].size;
+
+                        if (mi->bank[i].start <= phys_initrd_start &&
+                            end <= bank_end)
+                                initrd_node = mi->bank[i].node;
+                }
+        }
+
+        if (initrd_node == -1) {
+                printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
+                       "physical memory - disabling initrd\n",
+                       phys_initrd_start, end);
+                phys_initrd_start = phys_initrd_size = 0;
+        }
+#endif
+
+        return initrd_node;
+}
+
+/*
+ * Reserve the various regions of node 0
+ */
+static __init void reserve_node_zero(unsigned int bootmap_pfn, unsigned int bootmap_pages)
+{
+        pg_data_t *pgdat = NODE_DATA(0);
+        unsigned long res_size = 0;
+
+        /*
+         * Register the kernel text and data with bootmem.
+         * Note that this can only be in node 0.
+         */
+#ifdef CONFIG_XIP_KERNEL
+        reserve_bootmem_node(pgdat, __pa(&__data_start), &_end - &__data_start);
+#else
+        reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext);
+#endif
+
+        /*
+         * Reserve the page tables.  These are already in use,
+         * and can only be in node 0.
+         */
+        reserve_bootmem_node(pgdat, __pa(swapper_pg_dir),
+                             PTRS_PER_PGD * sizeof(pgd_t));
+
+        /*
+         * And don't forget to reserve the allocator bitmap,
+         * which will be freed later.
+         */
+        reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT,
+                             bootmap_pages << PAGE_SHIFT);
+
+        /*
+         * Hmm... This should go elsewhere, but we really really need to
+         * stop things allocating the low memory; ideally we need a better
+         * implementation of GFP_DMA which does not assume that DMA-able
+         * memory starts at zero.
+         */
+        if (machine_is_integrator() || machine_is_cintegrator())
+                res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
+
+        /*
+         * These should likewise go elsewhere.  They pre-reserve the
+         * screen memory region at the start of main system memory.
+         */
+        if (machine_is_edb7211())
+                res_size = 0x00020000;
+        if (machine_is_p720t())
+                res_size = 0x00014000;
+
+#ifdef CONFIG_SA1111
+        /*
+         * Because of the SA1111 DMA bug, we want to preserve our
+         * precious DMA-able memory...
+         */
+        res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
+#endif
+        if (res_size)
+                reserve_bootmem_node(pgdat, PHYS_OFFSET, res_size);
+}
+
+/*
+ * Register all available RAM in this node with the bootmem allocator.
+ */
+static inline void free_bootmem_node_bank(int node, struct meminfo *mi)
+{
+        pg_data_t *pgdat = NODE_DATA(node);
+        int bank;
+
+        for (bank = 0; bank < mi->nr_banks; bank++)
+                if (mi->bank[bank].node == node)
+                        free_bootmem_node(pgdat, mi->bank[bank].start,
+                                          mi->bank[bank].size);
+}
+
+/*
+ * Initialise the bootmem allocator for all nodes.  This is called
+ * early during the architecture specific initialisation.
+ */
+static void __init bootmem_init(struct meminfo *mi)
+{
+        struct node_info node_info[MAX_NUMNODES], *np = node_info;
+        unsigned int bootmap_pages, bootmap_pfn, map_pg;
+        int node, initrd_node;
+
+        bootmap_pages = find_memend_and_nodes(mi, np);
+        bootmap_pfn   = find_bootmap_pfn(0, mi, bootmap_pages);
+        initrd_node   = check_initrd(mi);
+
+        map_pg = bootmap_pfn;
+
+        /*
+         * Initialise the bootmem nodes.
+         *
+         * What we really want to do is:
+         *
+         *   unmap_all_regions_except_kernel();
+         *   for_each_node_in_reverse_order(node) {
+         *     map_node(node);
+         *     allocate_bootmem_map(node);
+         *     init_bootmem_node(node);
+         *     free_bootmem_node(node);
+         *   }
+         *
+         * but this is a 2.5-type change.  For now, we just set
+         * the nodes up in reverse order.
+         *
+         * (we could also do with rolling bootmem_init and paging_init
+         * into one generic "memory_init" type function).
+         */
+        np += num_online_nodes() - 1;
+        for (node = num_online_nodes() - 1; node >= 0; node--, np--) {
+                /*
+                 * If there are no pages in this node, ignore it.
+                 * Note that node 0 must always have some pages.
+                 */
+                if (np->end == 0 || !node_online(node)) {
+                        if (node == 0)
+                                BUG();
+                        continue;
+                }
+
+                /*
+                 * Initialise the bootmem allocator.
+                 */
+                init_bootmem_node(NODE_DATA(node), map_pg, np->start, np->end);
+                free_bootmem_node_bank(node, mi);
+                map_pg += np->bootmap_pages;
+
+                /*
+                 * If this is node 0, we need to reserve some areas ASAP -
+                 * we may use bootmem on node 0 to setup the other nodes.
+                 */
+                if (node == 0)
+                        reserve_node_zero(bootmap_pfn, bootmap_pages);
+        }
+
+
+#ifdef CONFIG_BLK_DEV_INITRD
+        if (phys_initrd_size && initrd_node >= 0) {
+                reserve_bootmem_node(NODE_DATA(initrd_node), phys_initrd_start,
+                                     phys_initrd_size);
+                initrd_start = __phys_to_virt(phys_initrd_start);
+                initrd_end = initrd_start + phys_initrd_size;
+        }
+#endif
+
+        BUG_ON(map_pg != bootmap_pfn + bootmap_pages);
+}
+
+/*
+ * paging_init() sets up the page tables, initialises the zone memory
+ * maps, and sets up the zero page, bad page and bad page tables.
+ */
+void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc)
+{
+        void *zero_page;
+        int node;
+
+        bootmem_init(mi);
+
+        memcpy(&meminfo, mi, sizeof(meminfo));
+
+        /*
+         * allocate the zero page.  Note that we count on this going ok.
+         */
+        zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
+
+        /*
+         * initialise the page tables.
+         */
+        memtable_init(mi);
+        if (mdesc->map_io)
+                mdesc->map_io();
+        flush_tlb_all();
+
+        /*
+         * initialise the zones within each node
+         */
+        for_each_online_node(node) {
+                unsigned long zone_size[MAX_NR_ZONES];
+                unsigned long zhole_size[MAX_NR_ZONES];
+                struct bootmem_data *bdata;
+                pg_data_t *pgdat;
+                int i;
+
+                /*
+                 * Initialise the zone size information.
+                 */
+                for (i = 0; i < MAX_NR_ZONES; i++) {
+                        zone_size[i]  = 0;
+                        zhole_size[i] = 0;
+                }
+
+                pgdat = NODE_DATA(node);
+                bdata = pgdat->bdata;
+
+                /*
+                 * The size of this node has already been determined.
+                 * If we need to do anything fancy with the allocation
+                 * of this memory to the zones, now is the time to do
+                 * it.
+                 */
+                zone_size[0] = bdata->node_low_pfn -
+                                (bdata->node_boot_start >> PAGE_SHIFT);
+
+                /*
+                 * If this zone has zero size, skip it.
+                 */
+                if (!zone_size[0])
+                        continue;
+
+                /*
+                 * For each bank in this node, calculate the size of the
+                 * holes.  holes = node_size - sum(bank_sizes_in_node)
+                 */
+                zhole_size[0] = zone_size[0];
+                for (i = 0; i < mi->nr_banks; i++) {
+                        if (mi->bank[i].node != node)
+                                continue;
+
+                        zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
+                }
+
+                /*
+                 * Adjust the sizes according to any special
+                 * requirements for this machine type.
+                 */
+                arch_adjust_zones(node, zone_size, zhole_size);
+
+                free_area_init_node(node, pgdat, zone_size,
+                                bdata->node_boot_start >> PAGE_SHIFT, zhole_size);
+        }
+
+        /*
+         * finish off the bad pages once
+         * the mem_map is initialised
+         */
+        memzero(zero_page, PAGE_SIZE);
+        empty_zero_page = virt_to_page(zero_page);
+        flush_dcache_page(empty_zero_page);
+}
+
+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);
+                set_page_count(page, 1);
+                free_page(addr);
+                totalram_pages++;
+        }
+
+        if (size && s)
+                printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
+}
+
+/*
+ * mem_init() marks the free areas in the mem_map and tells us how much
+ * memory is free.  This is done after various parts of the system have
+ * claimed their memory after the kernel image.
+ */
+void __init mem_init(void)
+{
+        unsigned int codepages, datapages, initpages;
+        int i, node;
+
+        codepages = &_etext - &_text;
+        datapages = &_end - &__data_start;
+        initpages = &__init_end - &__init_begin;
+
+#ifndef CONFIG_DISCONTIGMEM
+        max_mapnr   = virt_to_page(high_memory) - mem_map;
+#endif
+
+        /*
+         * We may have non-contiguous memory.
+         */
+        if (meminfo.nr_banks != 1)
+                create_memmap_holes(&meminfo);
+
+        /* this will put all unused low memory onto the freelists */
+        for_each_online_node(node) {
+                pg_data_t *pgdat = NODE_DATA(node);
+
+                if (pgdat->node_spanned_pages != 0)
+                        totalram_pages += free_all_bootmem_node(pgdat);
+        }
+
+#ifdef CONFIG_SA1111
+        /* now that our DMA memory is actually so designated, we can free it */
+        free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
+#endif
+
+        /*
+         * Since our memory may not be contiguous, calculate the
+         * real number of pages we have in this system
+         */
+        printk(KERN_INFO "Memory:");
+
+        num_physpages = 0;
+        for (i = 0; i < meminfo.nr_banks; i++) {
+                num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
+                printk(" %ldMB", meminfo.bank[i].size >> 20);
+        }
+
+        printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
+        printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
+                "%dK data, %dK init)\n",
+                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+                codepages >> 10, datapages >> 10, initpages >> 10);
+
+        if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
+                extern int sysctl_overcommit_memory;
+                /*
+                 * On a machine this small we won't get
+                 * anywhere without overcommit, so turn
+                 * it on by default.
+                 */
+                sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
+        }
+}
+
+void free_initmem(void)
+{
+        if (!machine_is_integrator() && !machine_is_cintegrator()) {
+                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