Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 *  PowerPC version

 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)

 *

 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)

 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)

 *    Copyright (C) 1996 Paul Mackerras

 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)

 *

 *  Derived from "arch/i386/mm/init.c"

 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds

 *

 *  This program is free software; you can redistribute it and/or

 *  modify it under the terms of the GNU General Public License

 *  as published by the Free Software Foundation; either version

 *  2 of the License, or (at your option) any later version.

 *

 */

#include <linux/module.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/string.h>

#include <linux/types.h>

#include <linux/mm.h>

#include <linux/stddef.h>

#include <linux/init.h>

#include <linux/bootmem.h>

#include <linux/highmem.h>

#include <linux/initrd.h>

#include <linux/pagemap.h>

#include <asm/pgalloc.h>

#include <asm/prom.h>

#include <asm/io.h>

#include <asm/mmu_context.h>

#include <asm/pgtable.h>

#include <asm/mmu.h>

#include <asm/smp.h>

#include <asm/machdep.h>

#include <asm/btext.h>

#include <asm/tlb.h>

#include <asm/lmb.h>

#include <asm/sections.h>

#include "mmu_decl.h"

#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)

/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */

#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))

#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"

#endif

#endif

#define MAX_LOW_MEM     CONFIG_LOWMEM_SIZE

DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

unsigned long total_memory;

unsigned long total_lowmem;

unsigned long ppc_memstart;

unsigned long ppc_memoffset = PAGE_OFFSET;

int boot_mapsize;

#ifdef CONFIG_PPC_PMAC

unsigned long agp_special_page;

EXPORT_SYMBOL(agp_special_page);

#endif

#ifdef CONFIG_HIGHMEM

pte_t *kmap_pte;

pgprot_t kmap_prot;

EXPORT_SYMBOL(kmap_prot);

EXPORT_SYMBOL(kmap_pte);

#endif

void MMU_init(void);

/* XXX should be in current.h  -- paulus */

extern struct task_struct *current_set[NR_CPUS];

extern int init_bootmem_done;

/*

 * this tells the system to map all of ram with the segregs

 * (i.e. page tables) instead of the bats.

 * -- Cort

 */

int __map_without_bats;

int __map_without_ltlbs;

/* max amount of low RAM to map in */

unsigned long __max_low_memory = MAX_LOW_MEM;

/*

 * limit of what is accessible with initial MMU setup -

 * 256MB usually, but only 16MB on 601.

 */

unsigned long __initial_memory_limit = 0x10000000;

/*

 * Check for command-line options that affect what MMU_init will do.

 */

void MMU_setup(void)

{

        /* Check for nobats option (used in mapin_ram). */

        if (strstr(cmd_line, "nobats")) {

                __map_without_bats = 1;

        }

        if (strstr(cmd_line, "noltlbs")) {

                __map_without_ltlbs = 1;

        }

#ifdef CONFIG_DEBUG_PAGEALLOC

        __map_without_bats = 1;

        __map_without_ltlbs = 1;

#endif

}

/*

 * MMU_init sets up the basic memory mappings for the kernel,

 * including both RAM and possibly some I/O regions,

 * and sets up the page tables and the MMU hardware ready to go.

 */

void __init MMU_init(void)

{

        if (ppc_md.progress)

                ppc_md.progress("MMU:enter", 0x111);

        /* 601 can only access 16MB at the moment */

        if (PVR_VER(mfspr(SPRN_PVR)) == 1)

                __initial_memory_limit = 0x01000000;

        /* 8xx can only access 8MB at the moment */

        if (PVR_VER(mfspr(SPRN_PVR)) == 0x50)

                __initial_memory_limit = 0x00800000;

        /* parse args from command line */

        MMU_setup();

        if (lmb.memory.cnt > 1) {

                lmb.memory.cnt = 1;

                lmb_analyze();

                printk(KERN_WARNING "Only using first contiguous memory region");

        }

        total_memory = lmb_end_of_DRAM();

        total_lowmem = total_memory;

#ifdef CONFIG_FSL_BOOKE

        /* Freescale Book-E parts expect lowmem to be mapped by fixed TLB

         * entries, so we need to adjust lowmem to match the amount we can map

         * in the fixed entries */

        adjust_total_lowmem();

#endif /* CONFIG_FSL_BOOKE */

        if (total_lowmem > __max_low_memory) {

                total_lowmem = __max_low_memory;

#ifndef CONFIG_HIGHMEM

                total_memory = total_lowmem;

                lmb_enforce_memory_limit(total_lowmem);

                lmb_analyze();

#endif /* CONFIG_HIGHMEM */

        }

        /* Initialize the MMU hardware */

        if (ppc_md.progress)

                ppc_md.progress("MMU:hw init", 0x300);

        MMU_init_hw();

        /* Map in all of RAM starting at KERNELBASE */

        if (ppc_md.progress)

                ppc_md.progress("MMU:mapin", 0x301);

        mapin_ram();

#ifdef CONFIG_HIGHMEM

        ioremap_base = PKMAP_BASE;

#else

        ioremap_base = 0xfe000000UL;    /* for now, could be 0xfffff000 */

#endif /* CONFIG_HIGHMEM */

        ioremap_bot = ioremap_base;

        /* Map in I/O resources */

        if (ppc_md.progress)

                ppc_md.progress("MMU:setio", 0x302);

        if (ppc_md.setup_io_mappings)

                ppc_md.setup_io_mappings();

        /* Initialize the context management stuff */

        mmu_context_init();

        if (ppc_md.progress)

                ppc_md.progress("MMU:exit", 0x211);

        /* From now on, btext is no longer BAT mapped if it was at all */

#ifdef CONFIG_BOOTX_TEXT

        btext_unmap();

#endif

}

/* This is only called until mem_init is done. */

void __init *early_get_page(void)

{

        void *p;

        if (init_bootmem_done) {

                p = alloc_bootmem_pages(PAGE_SIZE);

        } else {

                p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,

                                        __initial_memory_limit));

        }

        return p;

}

/* Free up now-unused memory */

static void free_sec(unsigned long start, unsigned long end, const char *name)

{

        unsigned long cnt = 0;

        while (start < end) {

                ClearPageReserved(virt_to_page(start));

                init_page_count(virt_to_page(start));

                free_page(start);

                cnt++;

                start += PAGE_SIZE;

        }

        if (cnt) {

                printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);

                totalram_pages += cnt;

        }

}

void free_initmem(void)

{

#define FREESEC(TYPE) \

        free_sec((unsigned long)(&__ ## TYPE ## _begin), \

                 (unsigned long)(&__ ## TYPE ## _end), \

                 #TYPE);

        printk ("Freeing unused kernel memory:");

        FREESEC(init);

        printk("\n");

        ppc_md.progress = NULL;

#undef FREESEC

}

#ifdef CONFIG_BLK_DEV_INITRD

void free_initrd_mem(unsigned long start, unsigned long end)

{

        if (start < end)

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

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

                ClearPageReserved(virt_to_page(start));

                init_page_count(virt_to_page(start));

                free_page(start);

                totalram_pages++;

        }

}

#endif

#ifdef CONFIG_PROC_KCORE

static struct kcore_list kcore_vmem;

static int __init setup_kcore(void)

{

        int i;

        for (i = 0; i < lmb.memory.cnt; i++) {

                unsigned long base;

                unsigned long size;

                struct kcore_list *kcore_mem;

                base = lmb.memory.region[i].base;

                size = lmb.memory.region[i].size;

                kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);

                if (!kcore_mem)

                        panic("%s: kmalloc failed\n", __FUNCTION__);

                /* must stay under 32 bits */

                if ( 0xfffffffful - (unsigned long)__va(base) < size) {

                        size = 0xfffffffful - (unsigned long)(__va(base));

                        printk(KERN_DEBUG "setup_kcore: restrict size=%lx\n",

                                                size);

                }

                kclist_add(kcore_mem, __va(base), size);

        }

        kclist_add(&kcore_vmem, (void *)VMALLOC_START,

                VMALLOC_END-VMALLOC_START);

        return 0;

}

module_init(setup_kcore);

#endif