xref: /openbmc/linux/arch/sparc/mm/init_32.c (revision 9be08a27)
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 
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 
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 
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 
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  */
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 		__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 
298 void free_initmem (void)
299 {
300 	free_initmem_default(POISON_FREE_INITMEM);
301 }
302 
303 #ifdef CONFIG_BLK_DEV_INITRD
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 
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