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/vaddrs.h>
33 #include <asm/setup.h>
34 #include <asm/tlb.h>
35 #include <asm/prom.h>
36 #include <asm/leon.h>
37
38 #include "mm_32.h"
39
40 static unsigned long *sparc_valid_addr_bitmap;
41
42 unsigned long phys_base;
43 EXPORT_SYMBOL(phys_base);
44
45 unsigned long pfn_base;
46 EXPORT_SYMBOL(pfn_base);
47
48 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
49
50 /* Initial ramdisk setup */
51 extern unsigned int sparc_ramdisk_image;
52 extern unsigned int sparc_ramdisk_size;
53
54 unsigned long highstart_pfn, highend_pfn;
55
56 unsigned long last_valid_pfn;
57
58 unsigned long calc_highpages(void)
59 {
60 int i;
61 int nr = 0;
62
63 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
64 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
65 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
66
67 if (end_pfn <= max_low_pfn)
68 continue;
69
70 if (start_pfn < max_low_pfn)
71 start_pfn = max_low_pfn;
72
73 nr += end_pfn - start_pfn;
74 }
75
76 return nr;
77 }
78
79 static unsigned long calc_max_low_pfn(void)
80 {
81 int i;
82 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
83 unsigned long curr_pfn, last_pfn;
84
85 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
86 for (i = 1; sp_banks[i].num_bytes != 0; i++) {
87 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
88
89 if (curr_pfn >= tmp) {
90 if (last_pfn < tmp)
91 tmp = last_pfn;
92 break;
93 }
94
95 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
96 }
97
98 return tmp;
99 }
100
101 static void __init find_ramdisk(unsigned long end_of_phys_memory)
102 {
103 #ifdef CONFIG_BLK_DEV_INITRD
104 unsigned long size;
105
106 /* Now have to check initial ramdisk, so that it won't pass
107 * the end of memory
108 */
109 if (sparc_ramdisk_image) {
110 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
111 sparc_ramdisk_image -= KERNBASE;
112 initrd_start = sparc_ramdisk_image + phys_base;
113 initrd_end = initrd_start + sparc_ramdisk_size;
114 if (initrd_end > end_of_phys_memory) {
115 printk(KERN_CRIT "initrd extends beyond end of memory "
116 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
117 initrd_end, end_of_phys_memory);
118 initrd_start = 0;
119 } else {
120 /* Reserve the initrd image area. */
121 size = initrd_end - initrd_start;
122 memblock_reserve(initrd_start, size);
123
124 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
125 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
126 }
127 }
128 #endif
129 }
130
131 unsigned long __init bootmem_init(unsigned long *pages_avail)
132 {
133 unsigned long start_pfn, bytes_avail, size;
134 unsigned long end_of_phys_memory = 0;
135 unsigned long high_pages = 0;
136 int i;
137
138 memblock_set_bottom_up(true);
139 memblock_allow_resize();
140
141 bytes_avail = 0UL;
142 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
143 end_of_phys_memory = sp_banks[i].base_addr +
144 sp_banks[i].num_bytes;
145 bytes_avail += sp_banks[i].num_bytes;
146 if (cmdline_memory_size) {
147 if (bytes_avail > cmdline_memory_size) {
148 unsigned long slack = bytes_avail - cmdline_memory_size;
149
150 bytes_avail -= slack;
151 end_of_phys_memory -= slack;
152
153 sp_banks[i].num_bytes -= slack;
154 if (sp_banks[i].num_bytes == 0) {
155 sp_banks[i].base_addr = 0xdeadbeef;
156 } else {
157 memblock_add(sp_banks[i].base_addr,
158 sp_banks[i].num_bytes);
159 sp_banks[i+1].num_bytes = 0;
160 sp_banks[i+1].base_addr = 0xdeadbeef;
161 }
162 break;
163 }
164 }
165 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
166 }
167
168 /* Start with page aligned address of last symbol in kernel
169 * image.
170 */
171 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
172
173 /* Now shift down to get the real physical page frame number. */
174 start_pfn >>= PAGE_SHIFT;
175
176 max_pfn = end_of_phys_memory >> PAGE_SHIFT;
177
178 max_low_pfn = max_pfn;
179 highstart_pfn = highend_pfn = max_pfn;
180
181 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
182 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
183 max_low_pfn = calc_max_low_pfn();
184 high_pages = calc_highpages();
185 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
186 high_pages >> (20 - PAGE_SHIFT));
187 }
188
189 find_ramdisk(end_of_phys_memory);
190
191 /* Reserve the kernel text/data/bss. */
192 size = (start_pfn << PAGE_SHIFT) - phys_base;
193 memblock_reserve(phys_base, size);
194 memblock_add(phys_base, size);
195
196 size = memblock_phys_mem_size() - memblock_reserved_size();
197 *pages_avail = (size >> PAGE_SHIFT) - high_pages;
198
199 /* Only allow low memory to be allocated via memblock allocation */
200 memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
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 */
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
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
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
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 memblock_alloc(i << 2, SMP_CACHE_BYTES);
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 memblock_free_all();
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
296 void sparc_flush_page_to_ram(struct page *page)
297 {
298 unsigned long vaddr = (unsigned long)page_address(page);
299
300 __flush_page_to_ram(vaddr);
301 }
302 EXPORT_SYMBOL(sparc_flush_page_to_ram);
303
304 void sparc_flush_folio_to_ram(struct folio *folio)
305 {
306 unsigned long vaddr = (unsigned long)folio_address(folio);
307 unsigned int i, nr = folio_nr_pages(folio);
308
309 for (i = 0; i < nr; i++)
310 __flush_page_to_ram(vaddr + i * PAGE_SIZE);
311 }
312 EXPORT_SYMBOL(sparc_flush_folio_to_ram);
313
314 static const pgprot_t protection_map[16] = {
315 [VM_NONE] = PAGE_NONE,
316 [VM_READ] = PAGE_READONLY,
317 [VM_WRITE] = PAGE_COPY,
318 [VM_WRITE | VM_READ] = PAGE_COPY,
319 [VM_EXEC] = PAGE_READONLY,
320 [VM_EXEC | VM_READ] = PAGE_READONLY,
321 [VM_EXEC | VM_WRITE] = PAGE_COPY,
322 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
323 [VM_SHARED] = PAGE_NONE,
324 [VM_SHARED | VM_READ] = PAGE_READONLY,
325 [VM_SHARED | VM_WRITE] = PAGE_SHARED,
326 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
327 [VM_SHARED | VM_EXEC] = PAGE_READONLY,
328 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY,
329 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
330 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED
331 };
332 DECLARE_VM_GET_PAGE_PROT
333
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