189 lines
4.7 KiB
C
189 lines
4.7 KiB
C
/*
|
|
* 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/highmem.h>
|
|
#include <linux/initrd.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/hugetlb.h>
|
|
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/prom.h>
|
|
#include <asm/io.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/sections.h>
|
|
#include <asm/hugetlb.h>
|
|
|
|
#include "mmu_decl.h"
|
|
|
|
#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
|
|
/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
|
|
#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET))
|
|
#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_KERNEL_START"
|
|
#endif
|
|
#endif
|
|
#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE
|
|
|
|
phys_addr_t total_memory;
|
|
phys_addr_t total_lowmem;
|
|
|
|
phys_addr_t memstart_addr = (phys_addr_t)~0ull;
|
|
EXPORT_SYMBOL(memstart_addr);
|
|
phys_addr_t kernstart_addr;
|
|
EXPORT_SYMBOL(kernstart_addr);
|
|
|
|
#ifdef CONFIG_RELOCATABLE
|
|
/* Used in __va()/__pa() */
|
|
long long virt_phys_offset;
|
|
EXPORT_SYMBOL(virt_phys_offset);
|
|
#endif
|
|
|
|
phys_addr_t lowmem_end_addr;
|
|
|
|
int boot_mapsize;
|
|
#ifdef CONFIG_PPC_PMAC
|
|
unsigned long agp_special_page;
|
|
EXPORT_SYMBOL(agp_special_page);
|
|
#endif
|
|
|
|
void MMU_init(void);
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/*
|
|
* This tells the system to allow ioremapping memory marked as reserved.
|
|
*/
|
|
int __allow_ioremap_reserved;
|
|
|
|
/* max amount of low RAM to map in */
|
|
unsigned long __max_low_memory = MAX_LOW_MEM;
|
|
|
|
/*
|
|
* Check for command-line options that affect what MMU_init will do.
|
|
*/
|
|
void __init MMU_setup(void)
|
|
{
|
|
/* Check for nobats option (used in mapin_ram). */
|
|
if (strstr(boot_command_line, "nobats")) {
|
|
__map_without_bats = 1;
|
|
}
|
|
|
|
if (strstr(boot_command_line, "noltlbs")) {
|
|
__map_without_ltlbs = 1;
|
|
}
|
|
if (debug_pagealloc_enabled()) {
|
|
__map_without_bats = 1;
|
|
__map_without_ltlbs = 1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
/* parse args from command line */
|
|
MMU_setup();
|
|
|
|
/*
|
|
* Reserve gigantic pages for hugetlb. This MUST occur before
|
|
* lowmem_end_addr is initialized below.
|
|
*/
|
|
reserve_hugetlb_gpages();
|
|
|
|
if (memblock.memory.cnt > 1) {
|
|
#ifndef CONFIG_WII
|
|
memblock_enforce_memory_limit(memblock.memory.regions[0].size);
|
|
pr_warn("Only using first contiguous memory region\n");
|
|
#else
|
|
wii_memory_fixups();
|
|
#endif
|
|
}
|
|
|
|
total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
|
|
lowmem_end_addr = memstart_addr + total_lowmem;
|
|
|
|
#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;
|
|
lowmem_end_addr = memstart_addr + total_lowmem;
|
|
#ifndef CONFIG_HIGHMEM
|
|
total_memory = total_lowmem;
|
|
memblock_enforce_memory_limit(total_lowmem);
|
|
#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();
|
|
|
|
/* Initialize early top-down ioremap allocator */
|
|
ioremap_bot = IOREMAP_TOP;
|
|
|
|
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
|
|
|
|
/* Shortly after that, the entire linear mapping will be available */
|
|
memblock_set_current_limit(lowmem_end_addr);
|
|
}
|