1/*
2 * arch/xtensa/mm/init.c
3 *
4 * Derived from MIPS, PPC.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 *
10 * Copyright (C) 2001 - 2005 Tensilica Inc.
11 * Copyright (C) 2014 - 2016 Cadence Design Systems Inc.
12 *
13 * Chris Zankel <chris@zankel.net>
14 * Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
15 * Marc Gauthier
16 * Kevin Chea
17 */
18
19#include <linux/kernel.h>
20#include <linux/errno.h>
21#include <linux/memblock.h>
22#include <linux/gfp.h>
23#include <linux/highmem.h>
24#include <linux/swap.h>
25#include <linux/mman.h>
26#include <linux/nodemask.h>
27#include <linux/mm.h>
28#include <linux/of_fdt.h>
29#include <linux/dma-map-ops.h>
30
31#include <asm/bootparam.h>
32#include <asm/page.h>
33#include <asm/sections.h>
34#include <asm/sysmem.h>
35
36/*
37 * Initialize the bootmem system and give it all low memory we have available.
38 */
39
40void __init bootmem_init(void)
41{
42 /* Reserve all memory below PHYS_OFFSET, as memory
43 * accounting doesn't work for pages below that address.
44 *
45 * If PHYS_OFFSET is zero reserve page at address 0:
46 * successfull allocations should never return NULL.
47 */
48 memblock_reserve(0, PHYS_OFFSET ? PHYS_OFFSET : 1);
49
50 early_init_fdt_scan_reserved_mem();
51
52 if (!memblock_phys_mem_size())
53 panic(fmt: "No memory found!\n");
54
55 min_low_pfn = PFN_UP(memblock_start_of_DRAM());
56 min_low_pfn = max(min_low_pfn, PFN_UP(PHYS_OFFSET));
57 max_pfn = PFN_DOWN(memblock_end_of_DRAM());
58 max_low_pfn = min(max_pfn, MAX_LOW_PFN);
59
60 early_memtest(start: (phys_addr_t)min_low_pfn << PAGE_SHIFT,
61 end: (phys_addr_t)max_low_pfn << PAGE_SHIFT);
62
63 memblock_set_current_limit(PFN_PHYS(max_low_pfn));
64 dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
65
66 memblock_dump_all();
67}
68
69static void __init print_vm_layout(void)
70{
71 pr_info("virtual kernel memory layout:\n"
72#ifdef CONFIG_KASAN
73 " kasan : 0x%08lx - 0x%08lx (%5lu MB)\n"
74#endif
75#ifdef CONFIG_MMU
76 " vmalloc : 0x%08lx - 0x%08lx (%5lu MB)\n"
77#endif
78#ifdef CONFIG_HIGHMEM
79 " pkmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
80 " fixmap : 0x%08lx - 0x%08lx (%5lu kB)\n"
81#endif
82 " lowmem : 0x%08lx - 0x%08lx (%5lu MB)\n"
83 " .text : 0x%08lx - 0x%08lx (%5lu kB)\n"
84 " .rodata : 0x%08lx - 0x%08lx (%5lu kB)\n"
85 " .data : 0x%08lx - 0x%08lx (%5lu kB)\n"
86 " .init : 0x%08lx - 0x%08lx (%5lu kB)\n"
87 " .bss : 0x%08lx - 0x%08lx (%5lu kB)\n",
88#ifdef CONFIG_KASAN
89 KASAN_SHADOW_START, KASAN_SHADOW_START + KASAN_SHADOW_SIZE,
90 KASAN_SHADOW_SIZE >> 20,
91#endif
92#ifdef CONFIG_MMU
93 VMALLOC_START, VMALLOC_END,
94 (VMALLOC_END - VMALLOC_START) >> 20,
95#ifdef CONFIG_HIGHMEM
96 PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
97 (LAST_PKMAP*PAGE_SIZE) >> 10,
98 FIXADDR_START, FIXADDR_END,
99 (FIXADDR_END - FIXADDR_START) >> 10,
100#endif
101 PAGE_OFFSET, PAGE_OFFSET +
102 (max_low_pfn - min_low_pfn) * PAGE_SIZE,
103#else
104 min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
105#endif
106 ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20,
107 (unsigned long)_text, (unsigned long)_etext,
108 (unsigned long)(_etext - _text) >> 10,
109 (unsigned long)__start_rodata, (unsigned long)__end_rodata,
110 (unsigned long)(__end_rodata - __start_rodata) >> 10,
111 (unsigned long)_sdata, (unsigned long)_edata,
112 (unsigned long)(_edata - _sdata) >> 10,
113 (unsigned long)__init_begin, (unsigned long)__init_end,
114 (unsigned long)(__init_end - __init_begin) >> 10,
115 (unsigned long)__bss_start, (unsigned long)__bss_stop,
116 (unsigned long)(__bss_stop - __bss_start) >> 10);
117}
118
119void __init zones_init(void)
120{
121 /* All pages are DMA-able, so we put them all in the DMA zone. */
122 unsigned long max_zone_pfn[MAX_NR_ZONES] = {
123 [ZONE_NORMAL] = max_low_pfn,
124#ifdef CONFIG_HIGHMEM
125 [ZONE_HIGHMEM] = max_pfn,
126#endif
127 };
128 free_area_init(max_zone_pfn);
129 print_vm_layout();
130}
131
132static void __init parse_memmap_one(char *p)
133{
134 char *oldp;
135 unsigned long start_at, mem_size;
136
137 if (!p)
138 return;
139
140 oldp = p;
141 mem_size = memparse(ptr: p, retptr: &p);
142 if (p == oldp)
143 return;
144
145 switch (*p) {
146 case '@':
147 start_at = memparse(ptr: p + 1, retptr: &p);
148 memblock_add(base: start_at, size: mem_size);
149 break;
150
151 case '$':
152 start_at = memparse(ptr: p + 1, retptr: &p);
153 memblock_reserve(base: start_at, size: mem_size);
154 break;
155
156 case 0:
157 memblock_reserve(base: mem_size, size: -mem_size);
158 break;
159
160 default:
161 pr_warn("Unrecognized memmap syntax: %s\n", p);
162 break;
163 }
164}
165
166static int __init parse_memmap_opt(char *str)
167{
168 while (str) {
169 char *k = strchr(str, ',');
170
171 if (k)
172 *k++ = 0;
173
174 parse_memmap_one(p: str);
175 str = k;
176 }
177
178 return 0;
179}
180early_param("memmap", parse_memmap_opt);
181
182#ifdef CONFIG_MMU
183static const pgprot_t protection_map[16] = {
184 [VM_NONE] = PAGE_NONE,
185 [VM_READ] = PAGE_READONLY,
186 [VM_WRITE] = PAGE_COPY,
187 [VM_WRITE | VM_READ] = PAGE_COPY,
188 [VM_EXEC] = PAGE_READONLY_EXEC,
189 [VM_EXEC | VM_READ] = PAGE_READONLY_EXEC,
190 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC,
191 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC,
192 [VM_SHARED] = PAGE_NONE,
193 [VM_SHARED | VM_READ] = PAGE_READONLY,
194 [VM_SHARED | VM_WRITE] = PAGE_SHARED,
195 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
196 [VM_SHARED | VM_EXEC] = PAGE_READONLY_EXEC,
197 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY_EXEC,
198 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC,
199 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC
200};
201DECLARE_VM_GET_PAGE_PROT
202#endif
203

source code of linux/arch/xtensa/mm/init.c