xref: /openbmc/linux/arch/xtensa/mm/init.c (revision 08283d30)
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-contiguous.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 
40 void __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("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((phys_addr_t)min_low_pfn << PAGE_SHIFT,
61 		      (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 
69 
70 void __init zones_init(void)
71 {
72 	/* All pages are DMA-able, so we put them all in the DMA zone. */
73 	unsigned long zones_size[MAX_NR_ZONES] = {
74 		[ZONE_NORMAL] = max_low_pfn - ARCH_PFN_OFFSET,
75 #ifdef CONFIG_HIGHMEM
76 		[ZONE_HIGHMEM] = max_pfn - max_low_pfn,
77 #endif
78 	};
79 	free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
80 }
81 
82 #ifdef CONFIG_HIGHMEM
83 static void __init free_area_high(unsigned long pfn, unsigned long end)
84 {
85 	for (; pfn < end; pfn++)
86 		free_highmem_page(pfn_to_page(pfn));
87 }
88 
89 static void __init free_highpages(void)
90 {
91 	unsigned long max_low = max_low_pfn;
92 	struct memblock_region *mem, *res;
93 
94 	reset_all_zones_managed_pages();
95 	/* set highmem page free */
96 	for_each_memblock(memory, mem) {
97 		unsigned long start = memblock_region_memory_base_pfn(mem);
98 		unsigned long end = memblock_region_memory_end_pfn(mem);
99 
100 		/* Ignore complete lowmem entries */
101 		if (end <= max_low)
102 			continue;
103 
104 		if (memblock_is_nomap(mem))
105 			continue;
106 
107 		/* Truncate partial highmem entries */
108 		if (start < max_low)
109 			start = max_low;
110 
111 		/* Find and exclude any reserved regions */
112 		for_each_memblock(reserved, res) {
113 			unsigned long res_start, res_end;
114 
115 			res_start = memblock_region_reserved_base_pfn(res);
116 			res_end = memblock_region_reserved_end_pfn(res);
117 
118 			if (res_end < start)
119 				continue;
120 			if (res_start < start)
121 				res_start = start;
122 			if (res_start > end)
123 				res_start = end;
124 			if (res_end > end)
125 				res_end = end;
126 			if (res_start != start)
127 				free_area_high(start, res_start);
128 			start = res_end;
129 			if (start == end)
130 				break;
131 		}
132 
133 		/* And now free anything which remains */
134 		if (start < end)
135 			free_area_high(start, end);
136 	}
137 }
138 #else
139 static void __init free_highpages(void)
140 {
141 }
142 #endif
143 
144 /*
145  * Initialize memory pages.
146  */
147 
148 void __init mem_init(void)
149 {
150 	free_highpages();
151 
152 	max_mapnr = max_pfn - ARCH_PFN_OFFSET;
153 	high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
154 
155 	memblock_free_all();
156 
157 	mem_init_print_info(NULL);
158 	pr_info("virtual kernel memory layout:\n"
159 #ifdef CONFIG_KASAN
160 		"    kasan   : 0x%08lx - 0x%08lx  (%5lu MB)\n"
161 #endif
162 #ifdef CONFIG_MMU
163 		"    vmalloc : 0x%08lx - 0x%08lx  (%5lu MB)\n"
164 #endif
165 #ifdef CONFIG_HIGHMEM
166 		"    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
167 		"    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"
168 #endif
169 		"    lowmem  : 0x%08lx - 0x%08lx  (%5lu MB)\n"
170 		"    .text   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
171 		"    .rodata : 0x%08lx - 0x%08lx  (%5lu kB)\n"
172 		"    .data   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
173 		"    .init   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
174 		"    .bss    : 0x%08lx - 0x%08lx  (%5lu kB)\n",
175 #ifdef CONFIG_KASAN
176 		KASAN_SHADOW_START, KASAN_SHADOW_START + KASAN_SHADOW_SIZE,
177 		KASAN_SHADOW_SIZE >> 20,
178 #endif
179 #ifdef CONFIG_MMU
180 		VMALLOC_START, VMALLOC_END,
181 		(VMALLOC_END - VMALLOC_START) >> 20,
182 #ifdef CONFIG_HIGHMEM
183 		PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
184 		(LAST_PKMAP*PAGE_SIZE) >> 10,
185 		FIXADDR_START, FIXADDR_TOP,
186 		(FIXADDR_TOP - FIXADDR_START) >> 10,
187 #endif
188 		PAGE_OFFSET, PAGE_OFFSET +
189 		(max_low_pfn - min_low_pfn) * PAGE_SIZE,
190 #else
191 		min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
192 #endif
193 		((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20,
194 		(unsigned long)_text, (unsigned long)_etext,
195 		(unsigned long)(_etext - _text) >> 10,
196 		(unsigned long)__start_rodata, (unsigned long)_sdata,
197 		(unsigned long)(_sdata - __start_rodata) >> 10,
198 		(unsigned long)_sdata, (unsigned long)_edata,
199 		(unsigned long)(_edata - _sdata) >> 10,
200 		(unsigned long)__init_begin, (unsigned long)__init_end,
201 		(unsigned long)(__init_end - __init_begin) >> 10,
202 		(unsigned long)__bss_start, (unsigned long)__bss_stop,
203 		(unsigned long)(__bss_stop - __bss_start) >> 10);
204 }
205 
206 static void __init parse_memmap_one(char *p)
207 {
208 	char *oldp;
209 	unsigned long start_at, mem_size;
210 
211 	if (!p)
212 		return;
213 
214 	oldp = p;
215 	mem_size = memparse(p, &p);
216 	if (p == oldp)
217 		return;
218 
219 	switch (*p) {
220 	case '@':
221 		start_at = memparse(p + 1, &p);
222 		memblock_add(start_at, mem_size);
223 		break;
224 
225 	case '$':
226 		start_at = memparse(p + 1, &p);
227 		memblock_reserve(start_at, mem_size);
228 		break;
229 
230 	case 0:
231 		memblock_reserve(mem_size, -mem_size);
232 		break;
233 
234 	default:
235 		pr_warn("Unrecognized memmap syntax: %s\n", p);
236 		break;
237 	}
238 }
239 
240 static int __init parse_memmap_opt(char *str)
241 {
242 	while (str) {
243 		char *k = strchr(str, ',');
244 
245 		if (k)
246 			*k++ = 0;
247 
248 		parse_memmap_one(str);
249 		str = k;
250 	}
251 
252 	return 0;
253 }
254 early_param("memmap", parse_memmap_opt);
255