xref: /openbmc/linux/arch/sparc/mm/init_32.c (revision 12eb4683)
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/tlb.h>
35 #include <asm/prom.h>
36 #include <asm/leon.h>
37 
38 unsigned long *sparc_valid_addr_bitmap;
39 EXPORT_SYMBOL(sparc_valid_addr_bitmap);
40 
41 unsigned long phys_base;
42 EXPORT_SYMBOL(phys_base);
43 
44 unsigned long pfn_base;
45 EXPORT_SYMBOL(pfn_base);
46 
47 struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
48 
49 /* Initial ramdisk setup */
50 extern unsigned int sparc_ramdisk_image;
51 extern unsigned int sparc_ramdisk_size;
52 
53 unsigned long highstart_pfn, highend_pfn;
54 
55 void show_mem(unsigned int filter)
56 {
57 	printk("Mem-info:\n");
58 	show_free_areas(filter);
59 	printk("Free swap:       %6ldkB\n",
60 	       get_nr_swap_pages() << (PAGE_SHIFT-10));
61 	printk("%ld pages of RAM\n", totalram_pages);
62 	printk("%ld free pages\n", nr_free_pages());
63 }
64 
65 
66 extern unsigned long cmdline_memory_size;
67 unsigned long last_valid_pfn;
68 
69 unsigned long calc_highpages(void)
70 {
71 	int i;
72 	int nr = 0;
73 
74 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
75 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
76 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
77 
78 		if (end_pfn <= max_low_pfn)
79 			continue;
80 
81 		if (start_pfn < max_low_pfn)
82 			start_pfn = max_low_pfn;
83 
84 		nr += end_pfn - start_pfn;
85 	}
86 
87 	return nr;
88 }
89 
90 static unsigned long calc_max_low_pfn(void)
91 {
92 	int i;
93 	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
94 	unsigned long curr_pfn, last_pfn;
95 
96 	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
97 	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
98 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
99 
100 		if (curr_pfn >= tmp) {
101 			if (last_pfn < tmp)
102 				tmp = last_pfn;
103 			break;
104 		}
105 
106 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
107 	}
108 
109 	return tmp;
110 }
111 
112 unsigned long __init bootmem_init(unsigned long *pages_avail)
113 {
114 	unsigned long bootmap_size, start_pfn;
115 	unsigned long end_of_phys_memory = 0UL;
116 	unsigned long bootmap_pfn, bytes_avail, size;
117 	int i;
118 
119 	bytes_avail = 0UL;
120 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
121 		end_of_phys_memory = sp_banks[i].base_addr +
122 			sp_banks[i].num_bytes;
123 		bytes_avail += sp_banks[i].num_bytes;
124 		if (cmdline_memory_size) {
125 			if (bytes_avail > cmdline_memory_size) {
126 				unsigned long slack = bytes_avail - cmdline_memory_size;
127 
128 				bytes_avail -= slack;
129 				end_of_phys_memory -= slack;
130 
131 				sp_banks[i].num_bytes -= slack;
132 				if (sp_banks[i].num_bytes == 0) {
133 					sp_banks[i].base_addr = 0xdeadbeef;
134 				} else {
135 					sp_banks[i+1].num_bytes = 0;
136 					sp_banks[i+1].base_addr = 0xdeadbeef;
137 				}
138 				break;
139 			}
140 		}
141 	}
142 
143 	/* Start with page aligned address of last symbol in kernel
144 	 * image.
145 	 */
146 	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
147 
148 	/* Now shift down to get the real physical page frame number. */
149 	start_pfn >>= PAGE_SHIFT;
150 
151 	bootmap_pfn = start_pfn;
152 
153 	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
154 
155 	max_low_pfn = max_pfn;
156 	highstart_pfn = highend_pfn = max_pfn;
157 
158 	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
159 		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
160 		max_low_pfn = calc_max_low_pfn();
161 		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
162 		    calc_highpages() >> (20 - PAGE_SHIFT));
163 	}
164 
165 #ifdef CONFIG_BLK_DEV_INITRD
166 	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
167 	if (sparc_ramdisk_image) {
168 		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
169 			sparc_ramdisk_image -= KERNBASE;
170 		initrd_start = sparc_ramdisk_image + phys_base;
171 		initrd_end = initrd_start + sparc_ramdisk_size;
172 		if (initrd_end > end_of_phys_memory) {
173 			printk(KERN_CRIT "initrd extends beyond end of memory "
174 		                 	 "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
175 			       initrd_end, end_of_phys_memory);
176 			initrd_start = 0;
177 		}
178 		if (initrd_start) {
179 			if (initrd_start >= (start_pfn << PAGE_SHIFT) &&
180 			    initrd_start < (start_pfn << PAGE_SHIFT) + 2 * PAGE_SIZE)
181 				bootmap_pfn = PAGE_ALIGN (initrd_end) >> PAGE_SHIFT;
182 		}
183 	}
184 #endif
185 	/* Initialize the boot-time allocator. */
186 	bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap_pfn, pfn_base,
187 					 max_low_pfn);
188 
189 	/* Now register the available physical memory with the
190 	 * allocator.
191 	 */
192 	*pages_avail = 0;
193 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
194 		unsigned long curr_pfn, last_pfn;
195 
196 		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
197 		if (curr_pfn >= max_low_pfn)
198 			break;
199 
200 		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
201 		if (last_pfn > max_low_pfn)
202 			last_pfn = max_low_pfn;
203 
204 		/*
205 		 * .. finally, did all the rounding and playing
206 		 * around just make the area go away?
207 		 */
208 		if (last_pfn <= curr_pfn)
209 			continue;
210 
211 		size = (last_pfn - curr_pfn) << PAGE_SHIFT;
212 		*pages_avail += last_pfn - curr_pfn;
213 
214 		free_bootmem(sp_banks[i].base_addr, size);
215 	}
216 
217 #ifdef CONFIG_BLK_DEV_INITRD
218 	if (initrd_start) {
219 		/* Reserve the initrd image area. */
220 		size = initrd_end - initrd_start;
221 		reserve_bootmem(initrd_start, size, BOOTMEM_DEFAULT);
222 		*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
223 
224 		initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
225 		initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
226 	}
227 #endif
228 	/* Reserve the kernel text/data/bss. */
229 	size = (start_pfn << PAGE_SHIFT) - phys_base;
230 	reserve_bootmem(phys_base, size, BOOTMEM_DEFAULT);
231 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
232 
233 	/* Reserve the bootmem map.   We do not account for it
234 	 * in pages_avail because we will release that memory
235 	 * in free_all_bootmem.
236 	 */
237 	size = bootmap_size;
238 	reserve_bootmem((bootmap_pfn << PAGE_SHIFT), size, BOOTMEM_DEFAULT);
239 	*pages_avail -= PAGE_ALIGN(size) >> PAGE_SHIFT;
240 
241 	return max_pfn;
242 }
243 
244 /*
245  * paging_init() sets up the page tables: We call the MMU specific
246  * init routine based upon the Sun model type on the Sparc.
247  *
248  */
249 extern void srmmu_paging_init(void);
250 extern void device_scan(void);
251 
252 void __init paging_init(void)
253 {
254 	srmmu_paging_init();
255 	prom_build_devicetree();
256 	of_fill_in_cpu_data();
257 	device_scan();
258 }
259 
260 static void __init taint_real_pages(void)
261 {
262 	int i;
263 
264 	for (i = 0; sp_banks[i].num_bytes; i++) {
265 		unsigned long start, end;
266 
267 		start = sp_banks[i].base_addr;
268 		end = start + sp_banks[i].num_bytes;
269 
270 		while (start < end) {
271 			set_bit(start >> 20, sparc_valid_addr_bitmap);
272 			start += PAGE_SIZE;
273 		}
274 	}
275 }
276 
277 static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
278 {
279 	unsigned long tmp;
280 
281 #ifdef CONFIG_DEBUG_HIGHMEM
282 	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
283 #endif
284 
285 	for (tmp = start_pfn; tmp < end_pfn; tmp++)
286 		free_highmem_page(pfn_to_page(tmp));
287 }
288 
289 void __init mem_init(void)
290 {
291 	int i;
292 
293 	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
294 		prom_printf("BUG: fixmap and pkmap areas overlap\n");
295 		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
296 		       PKMAP_BASE,
297 		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
298 		       FIXADDR_START);
299 		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
300 		prom_halt();
301 	}
302 
303 
304 	/* Saves us work later. */
305 	memset((void *)&empty_zero_page, 0, PAGE_SIZE);
306 
307 	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
308 	i += 1;
309 	sparc_valid_addr_bitmap = (unsigned long *)
310 		__alloc_bootmem(i << 2, SMP_CACHE_BYTES, 0UL);
311 
312 	if (sparc_valid_addr_bitmap == NULL) {
313 		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
314 		prom_halt();
315 	}
316 	memset(sparc_valid_addr_bitmap, 0, i << 2);
317 
318 	taint_real_pages();
319 
320 	max_mapnr = last_valid_pfn - pfn_base;
321 	high_memory = __va(max_low_pfn << PAGE_SHIFT);
322 	free_all_bootmem();
323 
324 	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
325 		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
326 		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
327 
328 		if (end_pfn <= highstart_pfn)
329 			continue;
330 
331 		if (start_pfn < highstart_pfn)
332 			start_pfn = highstart_pfn;
333 
334 		map_high_region(start_pfn, end_pfn);
335 	}
336 
337 	mem_init_print_info(NULL);
338 }
339 
340 void free_initmem (void)
341 {
342 	free_initmem_default(POISON_FREE_INITMEM);
343 }
344 
345 #ifdef CONFIG_BLK_DEV_INITRD
346 void free_initrd_mem(unsigned long start, unsigned long end)
347 {
348 	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
349 			   "initrd");
350 }
351 #endif
352 
353 void sparc_flush_page_to_ram(struct page *page)
354 {
355 	unsigned long vaddr = (unsigned long)page_address(page);
356 
357 	if (vaddr)
358 		__flush_page_to_ram(vaddr);
359 }
360 EXPORT_SYMBOL(sparc_flush_page_to_ram);
361