// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas ([email protected])
*
* Modifications by Paul Mackerras (PowerMac) ([email protected])
* and Cort Dougan (PReP) ([email protected])
* Copyright (C) 1996 Paul Mackerras
* PPC44x/36-bit changes by Matt Porter ([email protected])
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
*/
#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/io.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 <asm/kup.h>
#include <asm/kasan.h>
#include <asm/fixmap.h>
#include <mm/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;
#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);
/* max amount of low RAM to map in */
unsigned long __max_low_memory = MAX_LOW_MEM;
/*
* 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);
total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
lowmem_end_addr = memstart_addr + total_lowmem;
#ifdef CONFIG_PPC_85xx
/* 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_PPC_85xx */
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
kasan_mmu_init();
setup_kup();
update_mmu_feature_fixups(MMU_FTR_KUAP);
/* Shortly after that, the entire linear mapping will be available */
memblock_set_current_limit(lowmem_end_addr);
}
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