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
41unsigned long *sparc_valid_addr_bitmap;
42EXPORT_SYMBOL(sparc_valid_addr_bitmap);
43
44unsigned long phys_base;
45EXPORT_SYMBOL(phys_base);
46
47unsigned long pfn_base;
48EXPORT_SYMBOL(pfn_base);
49
50struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
51
52/* Initial ramdisk setup */
53extern unsigned int sparc_ramdisk_image;
54extern unsigned int sparc_ramdisk_size;
55
56unsigned long highstart_pfn, highend_pfn;
57
58void 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
69unsigned long last_valid_pfn;
70
71unsigned 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
92static 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
114unsigned 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 */
251void __init paging_init(void)
252{
253	srmmu_paging_init();
254	prom_build_devicetree();
255	of_fill_in_cpu_data();
256	device_scan();
257}
258
259static 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
276static 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
288void __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
339void free_initmem (void)
340{
341	free_initmem_default(POISON_FREE_INITMEM);
342}
343
344#ifdef CONFIG_BLK_DEV_INITRD
345void 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
352void 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}
359EXPORT_SYMBOL(sparc_flush_page_to_ram);
360