xref: /openbmc/linux/arch/sparc/mm/init_32.c (revision f3539c12)
1 /*
2  *  linux/arch/sparc/mm/init.c
3  *
4  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5  *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
6  *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
7  *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
8  */
9 
10 #include <linux/module.h>
11 #include <linux/signal.h>
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/types.h>
17 #include <linux/ptrace.h>
18 #include <linux/mman.h>
19 #include <linux/mm.h>
20 #include <linux/swap.h>
21 #include <linux/initrd.h>
22 #include <linux/init.h>
23 #include <linux/highmem.h>
24 #include <linux/bootmem.h>
25 #include <linux/pagemap.h>
26 #include <linux/poison.h>
27 #include <linux/gfp.h>
28 
29 #include <asm/sections.h>
30 #include <asm/page.h>
31 #include <asm/pgtable.h>
32 #include <asm/vaddrs.h>
33 #include <asm/pgalloc.h>	/* bug in asm-generic/tlb.h: check_pgt_cache */
34 #include <asm/setup.h>
35 #include <asm/tlb.h>
36 #include <asm/prom.h>
37 #include <asm/leon.h>
38 
39 #include "mm_32.h"
40 
41 unsigned long *sparc_valid_addr_bitmap;
42 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
43 
44 unsigned long phys_base;
45 EXPORT_SYMBOL(phys_base);
46 
47 unsigned long pfn_base;
48 EXPORT_SYMBOL(pfn_base);
49 
50 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
51 
52 /* Initial ramdisk setup */
53 extern unsigned int sparc_ramdisk_image;
54 extern unsigned int sparc_ramdisk_size;
55 
56 unsigned long highstart_pfn, highend_pfn;
57 
58 void show_mem(unsigned int filter)
59 {
60 	printk("Mem-info:\n");
61 	show_free_areas(filter);
62 	printk("Free swap:       %6ldkB\n",
63 	       get_nr_swap_pages() << (PAGE_SHIFT-10));
64 	printk("%ld pages of RAM\n", totalram_pages);
65 	printk("%ld free pages\n", nr_free_pages());
66 }
67 
68 
69 unsigned long last_valid_pfn;
70 
71 unsigned long calc_highpages(void)
72 {
73 	int i;
74 	int nr = 0;
75 
76 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
77 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
78 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
79 
80 		if (end_pfn <= max_low_pfn)
81 			continue;
82 
83 		if (start_pfn < max_low_pfn)
84 			start_pfn = max_low_pfn;
85 
86 		nr += end_pfn - start_pfn;
87 	}
88 
89 	return nr;
90 }
91 
92 static unsigned long calc_max_low_pfn(void)
93 {
94 	int i;
95 	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
96 	unsigned long curr_pfn, last_pfn;
97 
98 	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
99 	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
100 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
101 
102 		if (curr_pfn >= tmp) {
103 			if (last_pfn < tmp)
104 				tmp = last_pfn;
105 			break;
106 		}
107 
108 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
109 	}
110 
111 	return tmp;
112 }
113 
114 unsigned long __init bootmem_init(unsigned long *pages_avail)
115 {
116 	unsigned long bootmap_size, start_pfn;
117 	unsigned long end_of_phys_memory = 0UL;
118 	unsigned long bootmap_pfn, bytes_avail, size;
119 	int i;
120 
121 	bytes_avail = 0UL;
122 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
123 		end_of_phys_memory = sp_banks[i].base_addr +
124 			sp_banks[i].num_bytes;
125 		bytes_avail += sp_banks[i].num_bytes;
126 		if (cmdline_memory_size) {
127 			if (bytes_avail > cmdline_memory_size) {
128 				unsigned long slack = bytes_avail - cmdline_memory_size;
129 
130 				bytes_avail -= slack;
131 				end_of_phys_memory -= slack;
132 
133 				sp_banks[i].num_bytes -= slack;
134 				if (sp_banks[i].num_bytes == 0) {
135 					sp_banks[i].base_addr = 0xdeadbeef;
136 				} else {
137 					sp_banks[i+1].num_bytes = 0;
138 					sp_banks[i+1].base_addr = 0xdeadbeef;
139 				}
140 				break;
141 			}
142 		}
143 	}
144 
145 	/* Start with page aligned address of last symbol in kernel
146 	 * image.
147 	 */
148 	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
149 
150 	/* Now shift down to get the real physical page frame number. */
151 	start_pfn >>= PAGE_SHIFT;
152 
153 	bootmap_pfn = start_pfn;
154 
155 	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
156 
157 	max_low_pfn = max_pfn;
158 	highstart_pfn = highend_pfn = max_pfn;
159 
160 	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
161 		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
162 		max_low_pfn = calc_max_low_pfn();
163 		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
164 		    calc_highpages() >> (20 - PAGE_SHIFT));
165 	}
166 
167 #ifdef CONFIG_BLK_DEV_INITRD
168 	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
169 	if (sparc_ramdisk_image) {
170 		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
171 			sparc_ramdisk_image -= KERNBASE;
172 		initrd_start = sparc_ramdisk_image + phys_base;
173 		initrd_end = initrd_start + sparc_ramdisk_size;
174 		if (initrd_end > end_of_phys_memory) {
175 			printk(KERN_CRIT "initrd extends beyond end of memory "
176 		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
177 			       initrd_end, end_of_phys_memory);
178 			initrd_start = 0;
179 		}
180 		if (initrd_start) {
181 			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
182 			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
183 				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
184 		}
185 	}
186 #endif
187 	/* Initialize the boot-time allocator. */
188 	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
189 					 max_low_pfn);
190 
191 	/* Now register the available physical memory with the
192 	 * allocator.
193 	 */
194 	*pages_avail = 0;
195 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
196 		unsigned long curr_pfn, last_pfn;
197 
198 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
199 		if (curr_pfn >= max_low_pfn)
200 			break;
201 
202 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
203 		if (last_pfn > max_low_pfn)
204 			last_pfn = max_low_pfn;
205 
206 		/*
207 		 * .. finally, did all the rounding and playing
208 		 * around just make the area go away?
209 		 */
210 		if (last_pfn <= curr_pfn)
211 			continue;
212 
213 		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
214 		*pages_avail += last_pfn - curr_pfn;
215 
216 		free_bootmem(sp_banks[i].base_addr, size);
217 	}
218 
219 #ifdef CONFIG_BLK_DEV_INITRD
220 	if (initrd_start) {
221 		/* Reserve the initrd image area. */
222 		size = initrd_end - initrd_start;
223 		reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
224 		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
225 
226 		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
227 		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
228 	}
229 #endif
230 	/* Reserve the kernel text/data/bss. */
231 	size = (start_pfn << PAGE_SHIFT) - phys_base;
232 	reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
233 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
234 
235 	/* Reserve the bootmem map.   We do not account for it
236 	 * in pages_avail because we will release that memory
237 	 * in free_all_bootmem.
238 	 */
239 	size = bootmap_size;
240 	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
241 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
242 
243 	return max_pfn;
244 }
245 
246 /*
247  * paging_init() sets up the page tables: We call the MMU specific
248  * init routine based upon the Sun model type on the Sparc.
249  *
250  */
251 void __init paging_init(void)
252 {
253 	srmmu_paging_init();
254 	prom_build_devicetree();
255 	of_fill_in_cpu_data();
256 	device_scan();
257 }
258 
259 static void __init taint_real_pages(void)
260 {
261 	int i;
262 
263 	for (i = 0; sp_banks[i].num_bytes; i++) {
264 		unsigned long start, end;
265 
266 		start = sp_banks[i].base_addr;
267 		end = start + sp_banks[i].num_bytes;
268 
269 		while (start < end) {
270 			set_bit(start >> 20, sparc_valid_addr_bitmap);
271 			start += PAGE_SIZE;
272 		}
273 	}
274 }
275 
276 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
277 {
278 	unsigned long tmp;
279 
280 #ifdef CONFIG_DEBUG_HIGHMEM
281 	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
282 #endif
283 
284 	for (tmp = start_pfn; tmp < end_pfn; tmp++)
285 		free_highmem_page(pfn_to_page(tmp));
286 }
287 
288 void __init mem_init(void)
289 {
290 	int i;
291 
292 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
293 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
294 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
295 		       PKMAP_BASE,
296 		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
297 		       FIXADDR_START);
298 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
299 		prom_halt();
300 	}
301 
302 
303 	/* Saves us work later. */
304 	memset((void *)&empty_zero_page, 0, PAGE_SIZE);
305 
306 	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
307 	i += 1;
308 	sparc_valid_addr_bitmap = (unsigned long *)
309 		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
310 
311 	if (sparc_valid_addr_bitmap == NULL) {
312 		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
313 		prom_halt();
314 	}
315 	memset(sparc_valid_addr_bitmap, 0, i << 2);
316 
317 	taint_real_pages();
318 
319 	max_mapnr = last_valid_pfn - pfn_base;
320 	high_memory = __va(max_low_pfn << PAGE_SHIFT);
321 	free_all_bootmem();
322 
323 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
324 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
325 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
326 
327 		if (end_pfn <= highstart_pfn)
328 			continue;
329 
330 		if (start_pfn < highstart_pfn)
331 			start_pfn = highstart_pfn;
332 
333 		map_high_region(start_pfn, end_pfn);
334 	}
335 
336 	mem_init_print_info(NULL);
337 }
338 
339 void free_initmem (void)
340 {
341 	free_initmem_default(POISON_FREE_INITMEM);
342 }
343 
344 #ifdef CONFIG_BLK_DEV_INITRD
345 void free_initrd_mem(unsigned long start, unsigned long end)
346 {
347 	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
348 			   "initrd");
349 }
350 #endif
351 
352 void sparc_flush_page_to_ram(struct page *page)
353 {
354 	unsigned long vaddr = (unsigned long)page_address(page);
355 
356 	if (vaddr)
357 		__flush_page_to_ram(vaddr);
358 }
359 EXPORT_SYMBOL(sparc_flush_page_to_ram);
360