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/bootmem.h>
26 #include <linux/memblock.h>
27 #include <linux/pagemap.h>
28 #include <linux/poison.h>
29 #include <linux/gfp.h>
30
31 #include <asm/sections.h>
32 #include <asm/page.h>
33 #include <asm/pgtable.h>
34 #include <asm/vaddrs.h>
35 #include <asm/pgalloc.h> /* bug in asm-generic/tlb.h: check_pgt_cache */
36 #include <asm/setup.h>
37 #include <asm/tlb.h>
38 #include <asm/prom.h>
39 #include <asm/leon.h>
40
41 #include "mm_32.h"
42
43 unsigned long *sparc_valid_addr_bitmap;
44 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
45
46 unsigned long phys_base;
47 EXPORT_SYMBOL(phys_base);
48
49 unsigned long pfn_base;
50 EXPORT_SYMBOL(pfn_base);
51
52 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
53
54 /* Initial ramdisk setup */
55 extern unsigned int sparc_ramdisk_image;
56 extern unsigned int sparc_ramdisk_size;
57
58 unsigned long highstart_pfn, highend_pfn;
59
60 unsigned long last_valid_pfn;
61
calc_highpages(void)62 unsigned long calc_highpages(void)
63 {
64 int i;
65 int nr = 0;
66
67 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
68 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
69 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
70
71 if (end_pfn <= max_low_pfn)
72 continue;
73
74 if (start_pfn < max_low_pfn)
75 start_pfn = max_low_pfn;
76
77 nr += end_pfn - start_pfn;
78 }
79
80 return nr;
81 }
82
calc_max_low_pfn(void)83 static unsigned long calc_max_low_pfn(void)
84 {
85 int i;
86 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
87 unsigned long curr_pfn, last_pfn;
88
89 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
90 for (i = 1; sp_banks[i].num_bytes != 0; i++) {
91 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
92
93 if (curr_pfn >= tmp) {
94 if (last_pfn < tmp)
95 tmp = last_pfn;
96 break;
97 }
98
99 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
100 }
101
102 return tmp;
103 }
104
find_ramdisk(unsigned long end_of_phys_memory)105 static void __init find_ramdisk(unsigned long end_of_phys_memory)
106 {
107 #ifdef CONFIG_BLK_DEV_INITRD
108 unsigned long size;
109
110 /* Now have to check initial ramdisk, so that it won't pass
111 * the end of memory
112 */
113 if (sparc_ramdisk_image) {
114 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
115 sparc_ramdisk_image -= KERNBASE;
116 initrd_start = sparc_ramdisk_image + phys_base;
117 initrd_end = initrd_start + sparc_ramdisk_size;
118 if (initrd_end > end_of_phys_memory) {
119 printk(KERN_CRIT "initrd extends beyond end of memory "
120 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
121 initrd_end, end_of_phys_memory);
122 initrd_start = 0;
123 } else {
124 /* Reserve the initrd image area. */
125 size = initrd_end - initrd_start;
126 memblock_reserve(initrd_start, size);
127
128 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
129 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
130 }
131 }
132 #endif
133 }
134
bootmem_init(unsigned long * pages_avail)135 unsigned long __init bootmem_init(unsigned long *pages_avail)
136 {
137 unsigned long start_pfn, bytes_avail, size;
138 unsigned long end_of_phys_memory = 0;
139 unsigned long high_pages = 0;
140 int i;
141
142 memblock_set_bottom_up(true);
143 memblock_allow_resize();
144
145 bytes_avail = 0UL;
146 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
147 end_of_phys_memory = sp_banks[i].base_addr +
148 sp_banks[i].num_bytes;
149 bytes_avail += sp_banks[i].num_bytes;
150 if (cmdline_memory_size) {
151 if (bytes_avail > cmdline_memory_size) {
152 unsigned long slack = bytes_avail - cmdline_memory_size;
153
154 bytes_avail -= slack;
155 end_of_phys_memory -= slack;
156
157 sp_banks[i].num_bytes -= slack;
158 if (sp_banks[i].num_bytes == 0) {
159 sp_banks[i].base_addr = 0xdeadbeef;
160 } else {
161 memblock_add(sp_banks[i].base_addr,
162 sp_banks[i].num_bytes);
163 sp_banks[i+1].num_bytes = 0;
164 sp_banks[i+1].base_addr = 0xdeadbeef;
165 }
166 break;
167 }
168 }
169 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
170 }
171
172 /* Start with page aligned address of last symbol in kernel
173 * image.
174 */
175 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
176
177 /* Now shift down to get the real physical page frame number. */
178 start_pfn >>= PAGE_SHIFT;
179
180 max_pfn = end_of_phys_memory >> PAGE_SHIFT;
181
182 max_low_pfn = max_pfn;
183 highstart_pfn = highend_pfn = max_pfn;
184
185 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
186 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
187 max_low_pfn = calc_max_low_pfn();
188 high_pages = calc_highpages();
189 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
190 high_pages >> (20 - PAGE_SHIFT));
191 }
192
193 find_ramdisk(end_of_phys_memory);
194
195 /* Reserve the kernel text/data/bss. */
196 size = (start_pfn << PAGE_SHIFT) - phys_base;
197 memblock_reserve(phys_base, size);
198
199 size = memblock_phys_mem_size() - memblock_reserved_size();
200 *pages_avail = (size >> PAGE_SHIFT) - high_pages;
201
202 return max_pfn;
203 }
204
205 /*
206 * paging_init() sets up the page tables: We call the MMU specific
207 * init routine based upon the Sun model type on the Sparc.
208 *
209 */
paging_init(void)210 void __init paging_init(void)
211 {
212 srmmu_paging_init();
213 prom_build_devicetree();
214 of_fill_in_cpu_data();
215 device_scan();
216 }
217
taint_real_pages(void)218 static void __init taint_real_pages(void)
219 {
220 int i;
221
222 for (i = 0; sp_banks[i].num_bytes; i++) {
223 unsigned long start, end;
224
225 start = sp_banks[i].base_addr;
226 end = start + sp_banks[i].num_bytes;
227
228 while (start < end) {
229 set_bit(start >> 20, sparc_valid_addr_bitmap);
230 start += PAGE_SIZE;
231 }
232 }
233 }
234
map_high_region(unsigned long start_pfn,unsigned long end_pfn)235 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
236 {
237 unsigned long tmp;
238
239 #ifdef CONFIG_DEBUG_HIGHMEM
240 printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
241 #endif
242
243 for (tmp = start_pfn; tmp < end_pfn; tmp++)
244 free_highmem_page(pfn_to_page(tmp));
245 }
246
mem_init(void)247 void __init mem_init(void)
248 {
249 int i;
250
251 if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
252 prom_printf("BUG: fixmap and pkmap areas overlap\n");
253 prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
254 PKMAP_BASE,
255 (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
256 FIXADDR_START);
257 prom_printf("Please mail sparclinux@vger.kernel.org.\n");
258 prom_halt();
259 }
260
261
262 /* Saves us work later. */
263 memset((void *)empty_zero_page, 0, PAGE_SIZE);
264
265 i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
266 i += 1;
267 sparc_valid_addr_bitmap = (unsigned long *)
268 __alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
269
270 if (sparc_valid_addr_bitmap == NULL) {
271 prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
272 prom_halt();
273 }
274 memset(sparc_valid_addr_bitmap, 0, i << 2);
275
276 taint_real_pages();
277
278 max_mapnr = last_valid_pfn - pfn_base;
279 high_memory = __va(max_low_pfn << PAGE_SHIFT);
280 free_all_bootmem();
281
282 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
283 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
284 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
285
286 if (end_pfn <= highstart_pfn)
287 continue;
288
289 if (start_pfn < highstart_pfn)
290 start_pfn = highstart_pfn;
291
292 map_high_region(start_pfn, end_pfn);
293 }
294
295 mem_init_print_info(NULL);
296 }
297
free_initmem(void)298 void free_initmem (void)
299 {
300 free_initmem_default(POISON_FREE_INITMEM);
301 }
302
303 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)304 void free_initrd_mem(unsigned long start, unsigned long end)
305 {
306 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
307 "initrd");
308 }
309 #endif
310
sparc_flush_page_to_ram(struct page * page)311 void sparc_flush_page_to_ram(struct page *page)
312 {
313 unsigned long vaddr = (unsigned long)page_address(page);
314
315 if (vaddr)
316 __flush_page_to_ram(vaddr);
317 }
318 EXPORT_SYMBOL(sparc_flush_page_to_ram);
319
