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/*

 * 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.

 *

 * arch/sh64/mm/init.c

 *

 * Copyright (C) 2000, 2001  Paolo Alberelli

 *

 */

#include <linux/init.h>

#include <linux/mm.h>

#include <linux/swap.h>

#include <linux/bootmem.h>

#include <linux/highmem.h>

#include <asm/mmu_context.h>

#include <asm/page.h>

#include <asm/pgalloc.h>

#include <asm/pgtable.h>

#include <asm/tlb.h>

#ifdef CONFIG_BLK_DEV_INITRD

#include <linux/blk.h>

#endif

mmu_gather_t mmu_gathers[NR_CPUS];

/*

 * Cache of MMU context last used.

 */

unsigned long mmu_context_cache;

pgd_t * mmu_pdtp_cache;

static unsigned long totalram_pages = 0;

static unsigned long totalhigh_pages = 0;

/*

 * BAD_PAGE is the page that is used for page faults when linux

 * is out-of-memory. Older versions of linux just did a

 * do_exit(), but using this instead means there is less risk

 * for a process dying in kernel mode, possibly leaving an inode

 * unused etc..

 *

 * BAD_PAGETABLE is the accompanying page-table: it is initialized

 * to point to BAD_PAGE entries.

 *

 * ZERO_PAGE is a special page that is used for zero-initialized

 * data and COW.

 */

extern unsigned char empty_zero_page[PAGE_SIZE];

extern unsigned char empty_bad_page[PAGE_SIZE];

extern pte_t empty_bad_pte_table[PTRS_PER_PTE];

extern pgd_t swapper_pg_dir[PTRS_PER_PGD];

extern char _text, _etext, _edata, __bss_start, _end;

extern char __init_begin, __init_end;

/* It'd be good if these lines were in the standard header file. */

#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 i, total = 0, reserved = 0;

        int shared = 0, cached = 0;

        printk("Mem-info:\n");

        show_free_areas();

        printk("Free swap:       %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));

        i = max_mapnr;

        while (i-- > 0) {

                total++;

                if (PageReserved(mem_map+i))

                        reserved++;

                else if (PageSwapCache(mem_map+i))

                        cached++;

                else if (page_count(mem_map+i))

                        shared += page_count(mem_map+i) - 1;

        }

        printk("%d pages of RAM\n",total);

        printk("%d reserved pages\n",reserved);

        printk("%d pages shared\n",shared);

        printk("%d pages swap cached\n",cached);

        show_buffers();

}

/*

 * paging_init() sets up the page tables.

 *

 * head.S already did a lot to set up address translation for the kernel.

 * Here we comes with:

 * . MMU enabled

 * . ASID set (SR)

 * .  some 512MB regions being mapped of which the most relevant here is:

 *   . CACHED segment (ASID 0 [irrelevant], shared AND NOT user)

 * . possible variable length regions being mapped as:

 *   . UNCACHED segment (ASID 0 [irrelevant], shared AND NOT user)

 * . All of the memory regions are placed, independently from the platform

 *   on high addresses, above 0x80000000.

 * . swapper_pg_dir is already cleared out by the .space directive

 *   in any case swapper does not require a real page directory since

 *   it's all kernel contained.

 *

 * Those pesky NULL-reference errors in the kernel are then

 * dealt with by not mapping address 0x00000000 at all.

 *

 */

void __init paging_init(void)

{

        unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};

        mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;

        /*

         * All memory is good as ZONE_NORMAL (fall-through) and ZONE_DMA.

         */

        zones_size[ZONE_DMA] = MAX_LOW_PFN - START_PFN;

        free_area_init_node(0, NODE_DATA(0), 0,zones_size, __MEMORY_START, 0);

}

void __init mem_init(void)

{

        int codesize, reservedpages, datasize, initsize;

        int tmp;

        max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;

        high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);

        /*

         * Clear the zero-page.

         * This is not required but we might want to re-use

         * this very page to pass boot parameters, one day.

         */

        memset(empty_zero_page, 0, PAGE_SIZE);

        /* this will put all low memory onto the freelists */

        totalram_pages += free_all_bootmem();

        reservedpages = 0;

        for (tmp = 0; tmp < num_physpages; tmp++)

                /*

                 * Only count reserved RAM pages

                 */

                if (PageReserved(mem_map+tmp))

                        reservedpages++;

        codesize =  (unsigned long) &_etext - (unsigned long) &_text;

        datasize =  (unsigned long) &_edata - (unsigned long) &_etext;

        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),

                max_mapnr << (PAGE_SHIFT-10),

                codesize >> 10,

                reservedpages << (PAGE_SHIFT-10),

                datasize >> 10,

                initsize >> 10);

}

void free_initmem(void)

{

        unsigned long addr;

        addr = (unsigned long)(&__init_begin);

        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {

                ClearPageReserved(mem_map + MAP_NR(addr));

                set_page_count(mem_map+MAP_NR(addr), 1);

                free_page(addr);

                totalram_pages++;

        }

        printk ("Freeing unused kernel memory: %ldk freed\n", (&__init_end - &__init_begin) >> 10);

}

#ifdef CONFIG_BLK_DEV_INITRD

void free_initrd_mem(unsigned long start, unsigned long end)

{

        unsigned long p;

        for (p = start; p < end; p += PAGE_SIZE) {

                ClearPageReserved(mem_map + MAP_NR(p));

                set_page_count(mem_map+MAP_NR(p), 1);

                free_page(p);

                totalram_pages++;

        }

        printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);

}

#endif

void si_meminfo(struct sysinfo *val)

{

        val->totalram = totalram_pages;

        val->sharedram = 0;

        val->freeram = nr_free_pages();

        val->bufferram = atomic_read(&buffermem_pages);

        val->totalhigh = totalhigh_pages;

        val->freehigh = nr_free_highpages();

        val->mem_unit = PAGE_SIZE;

        return;

}