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v6.8
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  PowerPC version
  4 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  5 *
  6 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  7 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  8 *    Copyright (C) 1996 Paul Mackerras
  9 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
 10 *
 11 *  Derived from "arch/i386/mm/init.c"
 12 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 
 
 
 
 
 
 13 */
 14
 15#include <linux/module.h>
 16#include <linux/sched.h>
 17#include <linux/kernel.h>
 18#include <linux/errno.h>
 19#include <linux/string.h>
 20#include <linux/types.h>
 21#include <linux/mm.h>
 22#include <linux/stddef.h>
 23#include <linux/init.h>
 24#include <linux/highmem.h>
 25#include <linux/initrd.h>
 26#include <linux/pagemap.h>
 27#include <linux/memblock.h>
 28#include <linux/gfp.h>
 29#include <linux/slab.h>
 30#include <linux/hugetlb.h>
 31
 
 
 32#include <asm/io.h>
 
 33#include <asm/mmu.h>
 34#include <asm/smp.h>
 35#include <asm/machdep.h>
 36#include <asm/btext.h>
 37#include <asm/tlb.h>
 38#include <asm/sections.h>
 39#include <asm/hugetlb.h>
 40#include <asm/kup.h>
 41#include <asm/kasan.h>
 42#include <asm/fixmap.h>
 43
 44#include <mm/mmu_decl.h>
 45
 46#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
 47/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
 48#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET))
 49#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_KERNEL_START"
 50#endif
 51#endif
 52#define MAX_LOW_MEM	CONFIG_LOWMEM_SIZE
 53
 54phys_addr_t total_memory;
 55phys_addr_t total_lowmem;
 56
 
 
 
 
 
 57#ifdef CONFIG_RELOCATABLE
 58/* Used in __va()/__pa() */
 59long long virt_phys_offset;
 60EXPORT_SYMBOL(virt_phys_offset);
 61#endif
 62
 63phys_addr_t lowmem_end_addr;
 64
 65int boot_mapsize;
 66#ifdef CONFIG_PPC_PMAC
 67unsigned long agp_special_page;
 68EXPORT_SYMBOL(agp_special_page);
 69#endif
 70
 71void MMU_init(void);
 72
 
 
 
 
 
 
 
 
 73/* max amount of low RAM to map in */
 74unsigned long __max_low_memory = MAX_LOW_MEM;
 75
 76/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 77 * MMU_init sets up the basic memory mappings for the kernel,
 78 * including both RAM and possibly some I/O regions,
 79 * and sets up the page tables and the MMU hardware ready to go.
 80 */
 81void __init MMU_init(void)
 82{
 83	if (ppc_md.progress)
 84		ppc_md.progress("MMU:enter", 0x111);
 85
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 86	total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
 87	lowmem_end_addr = memstart_addr + total_lowmem;
 88
 89#ifdef CONFIG_PPC_85xx
 90	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
 91	 * entries, so we need to adjust lowmem to match the amount we can map
 92	 * in the fixed entries */
 93	adjust_total_lowmem();
 94#endif /* CONFIG_PPC_85xx */
 95
 96	if (total_lowmem > __max_low_memory) {
 97		total_lowmem = __max_low_memory;
 98		lowmem_end_addr = memstart_addr + total_lowmem;
 99#ifndef CONFIG_HIGHMEM
100		total_memory = total_lowmem;
101		memblock_enforce_memory_limit(total_lowmem);
102#endif /* CONFIG_HIGHMEM */
103	}
104
105	/* Initialize the MMU hardware */
106	if (ppc_md.progress)
107		ppc_md.progress("MMU:hw init", 0x300);
108	MMU_init_hw();
109
110	/* Map in all of RAM starting at KERNELBASE */
111	if (ppc_md.progress)
112		ppc_md.progress("MMU:mapin", 0x301);
113	mapin_ram();
114
115	/* Initialize early top-down ioremap allocator */
116	ioremap_bot = IOREMAP_TOP;
117
118	if (ppc_md.progress)
119		ppc_md.progress("MMU:exit", 0x211);
120
121	/* From now on, btext is no longer BAT mapped if it was at all */
122#ifdef CONFIG_BOOTX_TEXT
123	btext_unmap();
124#endif
125
126	kasan_mmu_init();
127
128	setup_kup();
129
130	update_mmu_feature_fixups(MMU_FTR_KUAP);
131
132	/* Shortly after that, the entire linear mapping will be available */
133	memblock_set_current_limit(lowmem_end_addr);
134}
v4.17
 
  1/*
  2 *  PowerPC version
  3 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  4 *
  5 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  6 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  7 *    Copyright (C) 1996 Paul Mackerras
  8 *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
  9 *
 10 *  Derived from "arch/i386/mm/init.c"
 11 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 12 *
 13 *  This program is free software; you can redistribute it and/or
 14 *  modify it under the terms of the GNU General Public License
 15 *  as published by the Free Software Foundation; either version
 16 *  2 of the License, or (at your option) any later version.
 17 *
 18 */
 19
 20#include <linux/module.h>
 21#include <linux/sched.h>
 22#include <linux/kernel.h>
 23#include <linux/errno.h>
 24#include <linux/string.h>
 25#include <linux/types.h>
 26#include <linux/mm.h>
 27#include <linux/stddef.h>
 28#include <linux/init.h>
 29#include <linux/highmem.h>
 30#include <linux/initrd.h>
 31#include <linux/pagemap.h>
 32#include <linux/memblock.h>
 33#include <linux/gfp.h>
 34#include <linux/slab.h>
 35#include <linux/hugetlb.h>
 36
 37#include <asm/pgalloc.h>
 38#include <asm/prom.h>
 39#include <asm/io.h>
 40#include <asm/pgtable.h>
 41#include <asm/mmu.h>
 42#include <asm/smp.h>
 43#include <asm/machdep.h>
 44#include <asm/btext.h>
 45#include <asm/tlb.h>
 46#include <asm/sections.h>
 47#include <asm/hugetlb.h>
 
 
 
 48
 49#include "mmu_decl.h"
 50
 51#if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
 52/* The amount of lowmem must be within 0xF0000000 - KERNELBASE. */
 53#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - PAGE_OFFSET))
 54#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_KERNEL_START"
 55#endif
 56#endif
 57#define MAX_LOW_MEM	CONFIG_LOWMEM_SIZE
 58
 59phys_addr_t total_memory;
 60phys_addr_t total_lowmem;
 61
 62phys_addr_t memstart_addr = (phys_addr_t)~0ull;
 63EXPORT_SYMBOL(memstart_addr);
 64phys_addr_t kernstart_addr;
 65EXPORT_SYMBOL(kernstart_addr);
 66
 67#ifdef CONFIG_RELOCATABLE
 68/* Used in __va()/__pa() */
 69long long virt_phys_offset;
 70EXPORT_SYMBOL(virt_phys_offset);
 71#endif
 72
 73phys_addr_t lowmem_end_addr;
 74
 75int boot_mapsize;
 76#ifdef CONFIG_PPC_PMAC
 77unsigned long agp_special_page;
 78EXPORT_SYMBOL(agp_special_page);
 79#endif
 80
 81void MMU_init(void);
 82
 83/*
 84 * this tells the system to map all of ram with the segregs
 85 * (i.e. page tables) instead of the bats.
 86 * -- Cort
 87 */
 88int __map_without_bats;
 89int __map_without_ltlbs;
 90
 91/* max amount of low RAM to map in */
 92unsigned long __max_low_memory = MAX_LOW_MEM;
 93
 94/*
 95 * Check for command-line options that affect what MMU_init will do.
 96 */
 97static void __init MMU_setup(void)
 98{
 99	/* Check for nobats option (used in mapin_ram). */
100	if (strstr(boot_command_line, "nobats")) {
101		__map_without_bats = 1;
102	}
103
104	if (strstr(boot_command_line, "noltlbs")) {
105		__map_without_ltlbs = 1;
106	}
107	if (debug_pagealloc_enabled()) {
108		__map_without_bats = 1;
109		__map_without_ltlbs = 1;
110	}
111#ifdef CONFIG_STRICT_KERNEL_RWX
112	if (rodata_enabled) {
113		__map_without_bats = 1;
114		__map_without_ltlbs = 1;
115	}
116#endif
117}
118
119/*
120 * MMU_init sets up the basic memory mappings for the kernel,
121 * including both RAM and possibly some I/O regions,
122 * and sets up the page tables and the MMU hardware ready to go.
123 */
124void __init MMU_init(void)
125{
126	if (ppc_md.progress)
127		ppc_md.progress("MMU:enter", 0x111);
128
129	/* parse args from command line */
130	MMU_setup();
131
132	/*
133	 * Reserve gigantic pages for hugetlb.  This MUST occur before
134	 * lowmem_end_addr is initialized below.
135	 */
136	if (memblock.memory.cnt > 1) {
137#ifndef CONFIG_WII
138		memblock_enforce_memory_limit(memblock.memory.regions[0].size);
139		pr_warn("Only using first contiguous memory region\n");
140#else
141		wii_memory_fixups();
142#endif
143	}
144
145	total_lowmem = total_memory = memblock_end_of_DRAM() - memstart_addr;
146	lowmem_end_addr = memstart_addr + total_lowmem;
147
148#ifdef CONFIG_FSL_BOOKE
149	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
150	 * entries, so we need to adjust lowmem to match the amount we can map
151	 * in the fixed entries */
152	adjust_total_lowmem();
153#endif /* CONFIG_FSL_BOOKE */
154
155	if (total_lowmem > __max_low_memory) {
156		total_lowmem = __max_low_memory;
157		lowmem_end_addr = memstart_addr + total_lowmem;
158#ifndef CONFIG_HIGHMEM
159		total_memory = total_lowmem;
160		memblock_enforce_memory_limit(total_lowmem);
161#endif /* CONFIG_HIGHMEM */
162	}
163
164	/* Initialize the MMU hardware */
165	if (ppc_md.progress)
166		ppc_md.progress("MMU:hw init", 0x300);
167	MMU_init_hw();
168
169	/* Map in all of RAM starting at KERNELBASE */
170	if (ppc_md.progress)
171		ppc_md.progress("MMU:mapin", 0x301);
172	mapin_ram();
173
174	/* Initialize early top-down ioremap allocator */
175	ioremap_bot = IOREMAP_TOP;
176
177	if (ppc_md.progress)
178		ppc_md.progress("MMU:exit", 0x211);
179
180	/* From now on, btext is no longer BAT mapped if it was at all */
181#ifdef CONFIG_BOOTX_TEXT
182	btext_unmap();
183#endif
 
 
 
 
 
 
184
185	/* Shortly after that, the entire linear mapping will be available */
186	memblock_set_current_limit(lowmem_end_addr);
187}