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 unsigned long *sparc_valid_addr_bitmap;
41 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
42
43 unsigned long phys_base;
44 EXPORT_SYMBOL(phys_base);
45
46 unsigned long pfn_base;
47 EXPORT_SYMBOL(pfn_base);
48
49 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
50
51 /* Initial ramdisk setup */
52 extern unsigned int sparc_ramdisk_image;
53 extern unsigned int sparc_ramdisk_size;
54
55 unsigned long highstart_pfn, highend_pfn;
56
57 unsigned long last_valid_pfn;
58
calc_highpages(void)59 unsigned long calc_highpages(void)
60 {
61 int i;
62 int nr = 0;
63
64 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
65 unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
66 unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
67
68 if (end_pfn <= max_low_pfn)
69 continue;
70
71 if (start_pfn < max_low_pfn)
72 start_pfn = max_low_pfn;
73
74 nr += end_pfn - start_pfn;
75 }
76
77 return nr;
78 }
79
calc_max_low_pfn(void)80 static unsigned long calc_max_low_pfn(void)
81 {
82 int i;
83 unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
84 unsigned long curr_pfn, last_pfn;
85
86 last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
87 for (i = 1; sp_banks[i].num_bytes != 0; i++) {
88 curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
89
90 if (curr_pfn >= tmp) {
91 if (last_pfn < tmp)
92 tmp = last_pfn;
93 break;
94 }
95
96 last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
97 }
98
99 return tmp;
100 }
101
find_ramdisk(unsigned long end_of_phys_memory)102 static void __init find_ramdisk(unsigned long end_of_phys_memory)
103 {
104 #ifdef CONFIG_BLK_DEV_INITRD
105 unsigned long size;
106
107 /* Now have to check initial ramdisk, so that it won't pass
108 * the end of memory
109 */
110 if (sparc_ramdisk_image) {
111 if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
112 sparc_ramdisk_image -= KERNBASE;
113 initrd_start = sparc_ramdisk_image + phys_base;
114 initrd_end = initrd_start + sparc_ramdisk_size;
115 if (initrd_end > end_of_phys_memory) {
116 printk(KERN_CRIT "initrd extends beyond end of memory "
117 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
118 initrd_end, end_of_phys_memory);
119 initrd_start = 0;
120 } else {
121 /* Reserve the initrd image area. */
122 size = initrd_end - initrd_start;
123 memblock_reserve(initrd_start, size);
124
125 initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
126 initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
127 }
128 }
129 #endif
130 }
131
bootmem_init(unsigned long * pages_avail)132 unsigned long __init bootmem_init(unsigned long *pages_avail)
133 {
134 unsigned long start_pfn, bytes_avail, size;
135 unsigned long end_of_phys_memory = 0;
136 unsigned long high_pages = 0;
137 int i;
138
139 memblock_set_bottom_up(true);
140 memblock_allow_resize();
141
142 bytes_avail = 0UL;
143 for (i = 0; sp_banks[i].num_bytes != 0; i++) {
144 end_of_phys_memory = sp_banks[i].base_addr +
145 sp_banks[i].num_bytes;
146 bytes_avail += sp_banks[i].num_bytes;
147 if (cmdline_memory_size) {
148 if (bytes_avail > cmdline_memory_size) {
149 unsigned long slack = bytes_avail - cmdline_memory_size;
150
151 bytes_avail -= slack;
152 end_of_phys_memory -= slack;
153
154 sp_banks[i].num_bytes -= slack;
155 if (sp_banks[i].num_bytes == 0) {
156 sp_banks[i].base_addr = 0xdeadbeef;
157 } else {
158 memblock_add(sp_banks[i].base_addr,
159 sp_banks[i].num_bytes);
160 sp_banks[i+1].num_bytes = 0;
161 sp_banks[i+1].base_addr = 0xdeadbeef;
162 }
163 break;
164 }
165 }
166 memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
167 }
168
169 /* Start with page aligned address of last symbol in kernel
170 * image.
171 */
172 start_pfn = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
173
174 /* Now shift down to get the real physical page frame number. */
175 start_pfn >>= PAGE_SHIFT;
176
177 max_pfn = end_of_phys_memory >> PAGE_SHIFT;
178
179 max_low_pfn = max_pfn;
180 highstart_pfn = highend_pfn = max_pfn;
181
182 if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
183 highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
184 max_low_pfn = calc_max_low_pfn();
185 high_pages = calc_highpages();
186 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
187 high_pages >> (20 - PAGE_SHIFT));
188 }
189
190 find_ramdisk(end_of_phys_memory);
191
192 /* Reserve the kernel text/data/bss. */
193 size = (start_pfn << PAGE_SHIFT) - phys_base;
194 memblock_reserve(phys_base, size);
195 memblock_add(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
sparc_flush_page_to_ram(struct page * page)297 void sparc_flush_page_to_ram(struct page *page)
298 {
299 unsigned long vaddr = (unsigned long)page_address(page);
300
301 if (vaddr)
302 __flush_page_to_ram(vaddr);
303 }
304 EXPORT_SYMBOL(sparc_flush_page_to_ram);
305