1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/sparc/mm/init.c
4 *
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
7 * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
8 * Copyright (C) 2000 Anton Blanchard (anton@samba.org)
9 */
10
11 #include <linux/module.h>
12 #include <linux/signal.h>
13 #include <linux/sched.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 #include <linux/ptrace.h>
19 #include <linux/mman.h>
20 #include <linux/mm.h>
21 #include <linux/swap.h>
22 #include <linux/initrd.h>
23 #include <linux/init.h>
24 #include <linux/highmem.h>
25 #include <linux/memblock.h>
26 #include <linux/pagemap.h>
27 #include <linux/poison.h>
28 #include <linux/gfp.h>
29
30 #include <asm/sections.h>
31 #include <asm/page.h>
32 #include <asm/pgtable.h>
33 #include <asm/vaddrs.h>
34 #include <asm/setup.h>
35 #include <asm/tlb.h>
36 #include <asm/prom.h>
37 #include <asm/leon.h>
38
39 #include "mm_32.h"
40
41 unsigned long *sparc_valid_addr_bitmap;
42 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
43
44 unsigned long phys_base;
45 EXPORT_SYMBOL(phys_base);
46
47 unsigned long pfn_base;
48 EXPORT_SYMBOL(pfn_base);
49
50 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
51
52 /* Initial ramdisk setup */
53 extern unsigned int sparc_ramdisk_image;
54 extern unsigned int sparc_ramdisk_size;
55
56 unsigned long highstart_pfn, highend_pfn;
57
58 unsigned long last_valid_pfn;
59
calc_highpages(void)60 unsigned long calc_highpages(void)
61 {
62 int i;
63 int nr = 0;
64
65 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
66 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
67 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
68
69 if (end_pfn <= max_low_pfn)
70 continue;
71
72 if (start_pfn < max_low_pfn)
73 start_pfn = max_low_pfn;
74
75 nr += end_pfn - start_pfn;
76 }
77
78 return nr;
79 }
80
calc_max_low_pfn(void)81 static unsigned long calc_max_low_pfn(void)
82 {
83 int i;
84 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
85 unsigned long curr_pfn, last_pfn;
86
87 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
88 for (i = 1; sp_banks[i].num_bytes != 0; i++) {
89 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
90
91 if (curr_pfn >= tmp) {
92 if (last_pfn < tmp)
93 tmp = last_pfn;
94 break;
95 }
96
97 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
98 }
99
100 return tmp;
101 }
102
find_ramdisk(unsigned long end_of_phys_memory)103 static void __init find_ramdisk(unsigned long end_of_phys_memory)
104 {
105 #ifdef CONFIG_BLK_DEV_INITRD
106 unsigned long size;
107
108 /* Now have to check initial ramdisk, so that it won't pass
109 * the end of memory
110 */
111 if (sparc_ramdisk_image) {
112 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
113 sparc_ramdisk_image -= KERNBASE;
114 initrd_start = sparc_ramdisk_image + phys_base;
115 initrd_end = initrd_start + sparc_ramdisk_size;
116 if (initrd_end > end_of_phys_memory) {
117 printk(KERN_CRIT "initrd extends beyond end of memory "
118 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
119 initrd_end, end_of_phys_memory);
120 initrd_start = 0;
121 } else {
122 /* Reserve the initrd image area. */
123 size = initrd_end - initrd_start;
124 memblock_reserve(initrd_start, size);
125
126 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
127 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
128 }
129 }
130 #endif
131 }
132
bootmem_init(unsigned long * pages_avail)133 unsigned long __init bootmem_init(unsigned long *pages_avail)
134 {
135 unsigned long start_pfn, bytes_avail, size;
136 unsigned long end_of_phys_memory = 0;
137 unsigned long high_pages = 0;
138 int i;
139
140 memblock_set_bottom_up(true);
141 memblock_allow_resize();
142
143 bytes_avail = 0UL;
144 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
145 end_of_phys_memory = sp_banks[i].base_addr +
146 sp_banks[i].num_bytes;
147 bytes_avail += sp_banks[i].num_bytes;
148 if (cmdline_memory_size) {
149 if (bytes_avail > cmdline_memory_size) {
150 unsigned long slack = bytes_avail - cmdline_memory_size;
151
152 bytes_avail -= slack;
153 end_of_phys_memory -= slack;
154
155 sp_banks[i].num_bytes -= slack;
156 if (sp_banks[i].num_bytes == 0) {
157 sp_banks[i].base_addr = 0xdeadbeef;
158 } else {
159 memblock_add(sp_banks[i].base_addr,
160 sp_banks[i].num_bytes);
161 sp_banks[i+1].num_bytes = 0;
162 sp_banks[i+1].base_addr = 0xdeadbeef;
163 }
164 break;
165 }
166 }
167 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
168 }
169
170 /* Start with page aligned address of last symbol in kernel
171 * image.
172 */
173 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
174
175 /* Now shift down to get the real physical page frame number. */
176 start_pfn >>= PAGE_SHIFT;
177
178 max_pfn = end_of_phys_memory >> PAGE_SHIFT;
179
180 max_low_pfn = max_pfn;
181 highstart_pfn = highend_pfn = max_pfn;
182
183 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
184 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
185 max_low_pfn = calc_max_low_pfn();
186 high_pages = calc_highpages();
187 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
188 high_pages >> (20 - PAGE_SHIFT));
189 }
190
191 find_ramdisk(end_of_phys_memory);
192
193 /* Reserve the kernel text/data/bss. */
194 size = (start_pfn << PAGE_SHIFT) - phys_base;
195 memblock_reserve(phys_base, size);
196
197 size = memblock_phys_mem_size() - memblock_reserved_size();
198 *pages_avail = (size >> PAGE_SHIFT) - high_pages;
199
200 /* Only allow low memory to be allocated via memblock allocation */
201 memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
202
203 return max_pfn;
204 }
205
206 /*
207 * paging_init() sets up the page tables: We call the MMU specific
208 * init routine based upon the Sun model type on the Sparc.
209 *
210 */
paging_init(void)211 void __init paging_init(void)
212 {
213 srmmu_paging_init();
214 prom_build_devicetree();
215 of_fill_in_cpu_data();
216 device_scan();
217 }
218
taint_real_pages(void)219 static void __init taint_real_pages(void)
220 {
221 int i;
222
223 for (i = 0; sp_banks[i].num_bytes; i++) {
224 unsigned long start, end;
225
226 start = sp_banks[i].base_addr;
227 end = start + sp_banks[i].num_bytes;
228
229 while (start < end) {
230 set_bit(start >> 20, sparc_valid_addr_bitmap);
231 start += PAGE_SIZE;
232 }
233 }
234 }
235
map_high_region(unsigned long start_pfn,unsigned long end_pfn)236 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
237 {
238 unsigned long tmp;
239
240 #ifdef CONFIG_DEBUG_HIGHMEM
241 printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
242 #endif
243
244 for (tmp = start_pfn; tmp < end_pfn; tmp++)
245 free_highmem_page(pfn_to_page(tmp));
246 }
247
mem_init(void)248 void __init mem_init(void)
249 {
250 int i;
251
252 if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
253 prom_printf("BUG: fixmap and pkmap areas overlap\n");
254 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
255 PKMAP_BASE,
256 (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
257 FIXADDR_START);
258 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
259 prom_halt();
260 }
261
262
263 /* Saves us work later. */
264 memset((void *)empty_zero_page, 0, PAGE_SIZE);
265
266 i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
267 i += 1;
268 sparc_valid_addr_bitmap = (unsigned long *)
269 memblock_alloc(i << 2, SMP_CACHE_BYTES);
270
271 if (sparc_valid_addr_bitmap == NULL) {
272 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
273 prom_halt();
274 }
275 memset(sparc_valid_addr_bitmap, 0, i << 2);
276
277 taint_real_pages();
278
279 max_mapnr = last_valid_pfn - pfn_base;
280 high_memory = __va(max_low_pfn << PAGE_SHIFT);
281 memblock_free_all();
282
283 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
284 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
285 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
286
287 if (end_pfn <= highstart_pfn)
288 continue;
289
290 if (start_pfn < highstart_pfn)
291 start_pfn = highstart_pfn;
292
293 map_high_region(start_pfn, end_pfn);
294 }
295
296 mem_init_print_info(NULL);
297 }
298
sparc_flush_page_to_ram(struct page * page)299 void sparc_flush_page_to_ram(struct page *page)
300 {
301 unsigned long vaddr = (unsigned long)page_address(page);
302
303 if (vaddr)
304 __flush_page_to_ram(vaddr);
305 }
306 EXPORT_SYMBOL(sparc_flush_page_to_ram);
307