xref: /openbmc/linux/arch/sparc/mm/init_32.c (revision feac8c8b)
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/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/pgalloc.h>	/* bug in asm-generic/tlb.h: check_pgt_cache */
35 #include <asm/setup.h>
36 #include <asm/tlb.h>
37 #include <asm/prom.h>
38 #include <asm/leon.h>
39 
40 #include "mm_32.h"
41 
42 unsigned long *sparc_valid_addr_bitmap;
43 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
44 
45 unsigned long phys_base;
46 EXPORT_SYMBOL(phys_base);
47 
48 unsigned long pfn_base;
49 EXPORT_SYMBOL(pfn_base);
50 
51 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
52 
53 /* Initial ramdisk setup */
54 extern unsigned int sparc_ramdisk_image;
55 extern unsigned int sparc_ramdisk_size;
56 
57 unsigned long highstart_pfn, highend_pfn;
58 
59 unsigned long last_valid_pfn;
60 
61 unsigned long calc_highpages(void)
62 {
63 	int i;
64 	int nr = 0;
65 
66 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
67 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
68 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
69 
70 		if (end_pfn <= max_low_pfn)
71 			continue;
72 
73 		if (start_pfn < max_low_pfn)
74 			start_pfn = max_low_pfn;
75 
76 		nr += end_pfn - start_pfn;
77 	}
78 
79 	return nr;
80 }
81 
82 static unsigned long calc_max_low_pfn(void)
83 {
84 	int i;
85 	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
86 	unsigned long curr_pfn, last_pfn;
87 
88 	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
89 	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
90 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
91 
92 		if (curr_pfn >= tmp) {
93 			if (last_pfn < tmp)
94 				tmp = last_pfn;
95 			break;
96 		}
97 
98 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
99 	}
100 
101 	return tmp;
102 }
103 
104 unsigned long __init bootmem_init(unsigned long *pages_avail)
105 {
106 	unsigned long bootmap_size, start_pfn;
107 	unsigned long end_of_phys_memory = 0UL;
108 	unsigned long bootmap_pfn, bytes_avail, size;
109 	int i;
110 
111 	bytes_avail = 0UL;
112 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
113 		end_of_phys_memory = sp_banks[i].base_addr +
114 			sp_banks[i].num_bytes;
115 		bytes_avail += sp_banks[i].num_bytes;
116 		if (cmdline_memory_size) {
117 			if (bytes_avail > cmdline_memory_size) {
118 				unsigned long slack = bytes_avail - cmdline_memory_size;
119 
120 				bytes_avail -= slack;
121 				end_of_phys_memory -= slack;
122 
123 				sp_banks[i].num_bytes -= slack;
124 				if (sp_banks[i].num_bytes == 0) {
125 					sp_banks[i].base_addr = 0xdeadbeef;
126 				} else {
127 					sp_banks[i+1].num_bytes = 0;
128 					sp_banks[i+1].base_addr = 0xdeadbeef;
129 				}
130 				break;
131 			}
132 		}
133 	}
134 
135 	/* Start with page aligned address of last symbol in kernel
136 	 * image.
137 	 */
138 	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
139 
140 	/* Now shift down to get the real physical page frame number. */
141 	start_pfn >>= PAGE_SHIFT;
142 
143 	bootmap_pfn = start_pfn;
144 
145 	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
146 
147 	max_low_pfn = max_pfn;
148 	highstart_pfn = highend_pfn = max_pfn;
149 
150 	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
151 		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
152 		max_low_pfn = calc_max_low_pfn();
153 		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
154 		    calc_highpages() >> (20 - PAGE_SHIFT));
155 	}
156 
157 #ifdef CONFIG_BLK_DEV_INITRD
158 	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
159 	if (sparc_ramdisk_image) {
160 		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
161 			sparc_ramdisk_image -= KERNBASE;
162 		initrd_start = sparc_ramdisk_image + phys_base;
163 		initrd_end = initrd_start + sparc_ramdisk_size;
164 		if (initrd_end > end_of_phys_memory) {
165 			printk(KERN_CRIT "initrd extends beyond end of memory "
166 		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
167 			       initrd_end, end_of_phys_memory);
168 			initrd_start = 0;
169 		}
170 		if (initrd_start) {
171 			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
172 			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
173 				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
174 		}
175 	}
176 #endif
177 	/* Initialize the boot-time allocator. */
178 	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
179 					 max_low_pfn);
180 
181 	/* Now register the available physical memory with the
182 	 * allocator.
183 	 */
184 	*pages_avail = 0;
185 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
186 		unsigned long curr_pfn, last_pfn;
187 
188 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
189 		if (curr_pfn >= max_low_pfn)
190 			break;
191 
192 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
193 		if (last_pfn > max_low_pfn)
194 			last_pfn = max_low_pfn;
195 
196 		/*
197 		 * .. finally, did all the rounding and playing
198 		 * around just make the area go away?
199 		 */
200 		if (last_pfn <= curr_pfn)
201 			continue;
202 
203 		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
204 		*pages_avail += last_pfn - curr_pfn;
205 
206 		free_bootmem(sp_banks[i].base_addr, size);
207 	}
208 
209 #ifdef CONFIG_BLK_DEV_INITRD
210 	if (initrd_start) {
211 		/* Reserve the initrd image area. */
212 		size = initrd_end - initrd_start;
213 		reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
214 		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
215 
216 		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
217 		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
218 	}
219 #endif
220 	/* Reserve the kernel text/data/bss. */
221 	size = (start_pfn << PAGE_SHIFT) - phys_base;
222 	reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
223 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
224 
225 	/* Reserve the bootmem map.   We do not account for it
226 	 * in pages_avail because we will release that memory
227 	 * in free_all_bootmem.
228 	 */
229 	size = bootmap_size;
230 	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
231 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
232 
233 	return max_pfn;
234 }
235 
236 /*
237  * paging_init() sets up the page tables: We call the MMU specific
238  * init routine based upon the Sun model type on the Sparc.
239  *
240  */
241 void __init paging_init(void)
242 {
243 	srmmu_paging_init();
244 	prom_build_devicetree();
245 	of_fill_in_cpu_data();
246 	device_scan();
247 }
248 
249 static void __init taint_real_pages(void)
250 {
251 	int i;
252 
253 	for (i = 0; sp_banks[i].num_bytes; i++) {
254 		unsigned long start, end;
255 
256 		start = sp_banks[i].base_addr;
257 		end = start + sp_banks[i].num_bytes;
258 
259 		while (start < end) {
260 			set_bit(start >> 20, sparc_valid_addr_bitmap);
261 			start += PAGE_SIZE;
262 		}
263 	}
264 }
265 
266 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
267 {
268 	unsigned long tmp;
269 
270 #ifdef CONFIG_DEBUG_HIGHMEM
271 	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
272 #endif
273 
274 	for (tmp = start_pfn; tmp < end_pfn; tmp++)
275 		free_highmem_page(pfn_to_page(tmp));
276 }
277 
278 void __init mem_init(void)
279 {
280 	int i;
281 
282 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
283 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
284 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
285 		       PKMAP_BASE,
286 		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
287 		       FIXADDR_START);
288 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
289 		prom_halt();
290 	}
291 
292 
293 	/* Saves us work later. */
294 	memset((void *)empty_zero_page, 0, PAGE_SIZE);
295 
296 	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
297 	i += 1;
298 	sparc_valid_addr_bitmap = (unsigned long *)
299 		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
300 
301 	if (sparc_valid_addr_bitmap == NULL) {
302 		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
303 		prom_halt();
304 	}
305 	memset(sparc_valid_addr_bitmap, 0, i << 2);
306 
307 	taint_real_pages();
308 
309 	max_mapnr = last_valid_pfn - pfn_base;
310 	high_memory = __va(max_low_pfn << PAGE_SHIFT);
311 	free_all_bootmem();
312 
313 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
314 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
315 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
316 
317 		if (end_pfn <= highstart_pfn)
318 			continue;
319 
320 		if (start_pfn < highstart_pfn)
321 			start_pfn = highstart_pfn;
322 
323 		map_high_region(start_pfn, end_pfn);
324 	}
325 
326 	mem_init_print_info(NULL);
327 }
328 
329 void free_initmem (void)
330 {
331 	free_initmem_default(POISON_FREE_INITMEM);
332 }
333 
334 #ifdef CONFIG_BLK_DEV_INITRD
335 void free_initrd_mem(unsigned long start, unsigned long end)
336 {
337 	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
338 			   "initrd");
339 }
340 #endif
341 
342 void sparc_flush_page_to_ram(struct page *page)
343 {
344 	unsigned long vaddr = (unsigned long)page_address(page);
345 
346 	if (vaddr)
347 		__flush_page_to_ram(vaddr);
348 }
349 EXPORT_SYMBOL(sparc_flush_page_to_ram);
350