2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1994 - 2000 Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
9 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
11 #include <linux/bug.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/signal.h>
15 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/string.h>
20 #include <linux/types.h>
21 #include <linux/pagemap.h>
22 #include <linux/ptrace.h>
23 #include <linux/mman.h>
25 #include <linux/bootmem.h>
26 #include <linux/highmem.h>
27 #include <linux/swap.h>
28 #include <linux/proc_fs.h>
29 #include <linux/pfn.h>
30 #include <linux/hardirq.h>
31 #include <linux/gfp.h>
32 #include <linux/kcore.h>
34 #include <asm/asm-offsets.h>
35 #include <asm/bootinfo.h>
36 #include <asm/cachectl.h>
39 #include <asm/kmap_types.h>
41 #include <asm/mmu_context.h>
42 #include <asm/sections.h>
43 #include <asm/pgtable.h>
44 #include <asm/pgalloc.h>
46 #include <asm/fixmap.h>
49 * We have up to 8 empty zeroed pages so we can map one of the right colour
50 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
51 * where we have to avoid VCED / VECI exceptions for good performance at
52 * any price. Since page is never written to after the initialization we
53 * don't have to care about aliases on other CPUs.
55 unsigned long empty_zero_page, zero_page_mask;
56 EXPORT_SYMBOL_GPL(empty_zero_page);
57 EXPORT_SYMBOL(zero_page_mask);
60 * Not static inline because used by IP27 special magic initialization code
62 void setup_zero_pages(void)
64 unsigned int order, i;
72 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
74 panic("Oh boy, that early out of memory?");
76 page = virt_to_page((void *)empty_zero_page);
77 split_page(page, order);
78 for (i = 0; i < (1 << order); i++, page++)
79 mark_page_reserved(page);
81 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
84 static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot)
86 enum fixed_addresses idx;
87 unsigned long vaddr, flags, entrylo;
88 unsigned long old_ctx;
92 BUG_ON(Page_dcache_dirty(page));
96 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
97 idx += in_interrupt() ? FIX_N_COLOURS : 0;
98 vaddr = __fix_to_virt(FIX_CMAP_END - idx);
99 pte = mk_pte(page, prot);
100 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
101 entrylo = pte_to_entrylo(pte.pte_high);
103 entrylo = pte_to_entrylo(pte_val(pte));
106 local_irq_save(flags);
107 old_ctx = read_c0_entryhi();
108 write_c0_entryhi(vaddr & (PAGE_MASK << 1));
109 write_c0_entrylo0(entrylo);
110 write_c0_entrylo1(entrylo);
112 entrylo = (pte.pte_low & _PFNX_MASK);
113 writex_c0_entrylo0(entrylo);
114 writex_c0_entrylo1(entrylo);
116 tlbidx = read_c0_wired();
117 write_c0_wired(tlbidx + 1);
118 write_c0_index(tlbidx);
122 write_c0_entryhi(old_ctx);
123 local_irq_restore(flags);
125 return (void*) vaddr;
128 void *kmap_coherent(struct page *page, unsigned long addr)
130 return __kmap_pgprot(page, addr, PAGE_KERNEL);
133 void *kmap_noncoherent(struct page *page, unsigned long addr)
135 return __kmap_pgprot(page, addr, PAGE_KERNEL_NC);
138 void kunmap_coherent(void)
141 unsigned long flags, old_ctx;
143 local_irq_save(flags);
144 old_ctx = read_c0_entryhi();
145 wired = read_c0_wired() - 1;
146 write_c0_wired(wired);
147 write_c0_index(wired);
148 write_c0_entryhi(UNIQUE_ENTRYHI(wired));
149 write_c0_entrylo0(0);
150 write_c0_entrylo1(0);
154 write_c0_entryhi(old_ctx);
155 local_irq_restore(flags);
160 void copy_user_highpage(struct page *to, struct page *from,
161 unsigned long vaddr, struct vm_area_struct *vma)
165 vto = kmap_atomic(to);
166 if (cpu_has_dc_aliases &&
167 page_mapped(from) && !Page_dcache_dirty(from)) {
168 vfrom = kmap_coherent(from, vaddr);
169 copy_page(vto, vfrom);
172 vfrom = kmap_atomic(from);
173 copy_page(vto, vfrom);
174 kunmap_atomic(vfrom);
176 if ((!cpu_has_ic_fills_f_dc) ||
177 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
178 flush_data_cache_page((unsigned long)vto);
180 /* Make sure this page is cleared on other CPU's too before using it */
184 void copy_to_user_page(struct vm_area_struct *vma,
185 struct page *page, unsigned long vaddr, void *dst, const void *src,
188 if (cpu_has_dc_aliases &&
189 page_mapped(page) && !Page_dcache_dirty(page)) {
190 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
191 memcpy(vto, src, len);
194 memcpy(dst, src, len);
195 if (cpu_has_dc_aliases)
196 SetPageDcacheDirty(page);
198 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
199 flush_cache_page(vma, vaddr, page_to_pfn(page));
202 void copy_from_user_page(struct vm_area_struct *vma,
203 struct page *page, unsigned long vaddr, void *dst, const void *src,
206 if (cpu_has_dc_aliases &&
207 page_mapped(page) && !Page_dcache_dirty(page)) {
208 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
209 memcpy(dst, vfrom, len);
212 memcpy(dst, src, len);
213 if (cpu_has_dc_aliases)
214 SetPageDcacheDirty(page);
217 EXPORT_SYMBOL_GPL(copy_from_user_page);
219 void __init fixrange_init(unsigned long start, unsigned long end,
222 #ifdef CONFIG_HIGHMEM
231 i = __pgd_offset(vaddr);
232 j = __pud_offset(vaddr);
233 k = __pmd_offset(vaddr);
236 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
238 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
240 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) {
241 if (pmd_none(*pmd)) {
242 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
243 set_pmd(pmd, __pmd((unsigned long)pte));
244 BUG_ON(pte != pte_offset_kernel(pmd, 0));
255 #ifndef CONFIG_NEED_MULTIPLE_NODES
256 int page_is_ram(unsigned long pagenr)
260 for (i = 0; i < boot_mem_map.nr_map; i++) {
261 unsigned long addr, end;
263 switch (boot_mem_map.map[i].type) {
265 case BOOT_MEM_INIT_RAM:
268 /* not usable memory */
272 addr = PFN_UP(boot_mem_map.map[i].addr);
273 end = PFN_DOWN(boot_mem_map.map[i].addr +
274 boot_mem_map.map[i].size);
276 if (pagenr >= addr && pagenr < end)
283 void __init paging_init(void)
285 unsigned long max_zone_pfns[MAX_NR_ZONES];
286 unsigned long lastpfn __maybe_unused;
290 #ifdef CONFIG_HIGHMEM
293 #ifdef CONFIG_ZONE_DMA
294 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
296 #ifdef CONFIG_ZONE_DMA32
297 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
299 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
300 lastpfn = max_low_pfn;
301 #ifdef CONFIG_HIGHMEM
302 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
303 lastpfn = highend_pfn;
305 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
306 printk(KERN_WARNING "This processor doesn't support highmem."
307 " %ldk highmem ignored\n",
308 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
309 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
310 lastpfn = max_low_pfn;
314 free_area_init_nodes(max_zone_pfns);
318 static struct kcore_list kcore_kseg0;
321 static inline void mem_init_free_highmem(void)
323 #ifdef CONFIG_HIGHMEM
326 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
327 struct page *page = pfn_to_page(tmp);
329 if (!page_is_ram(tmp))
330 SetPageReserved(page);
332 free_highmem_page(page);
337 unsigned __weak platform_maar_init(unsigned num_pairs)
339 struct maar_config cfg[BOOT_MEM_MAP_MAX];
340 unsigned i, num_configured, num_cfg = 0;
343 for (i = 0; i < boot_mem_map.nr_map; i++) {
344 switch (boot_mem_map.map[i].type) {
346 case BOOT_MEM_INIT_RAM:
352 skip = 0x10000 - (boot_mem_map.map[i].addr & 0xffff);
354 cfg[num_cfg].lower = boot_mem_map.map[i].addr;
355 cfg[num_cfg].lower += skip;
357 cfg[num_cfg].upper = cfg[num_cfg].lower;
358 cfg[num_cfg].upper += boot_mem_map.map[i].size - 1;
359 cfg[num_cfg].upper -= skip;
361 cfg[num_cfg].attrs = MIPS_MAAR_S;
365 num_configured = maar_config(cfg, num_cfg, num_pairs);
366 if (num_configured < num_cfg)
367 pr_warn("Not enough MAAR pairs (%u) for all bootmem regions (%u)\n",
370 return num_configured;
373 static void maar_init(void)
375 unsigned num_maars, used, i;
380 /* Detect the number of MAARs */
382 back_to_back_c0_hazard();
383 num_maars = read_c0_maari() + 1;
385 /* MAARs should be in pairs */
386 WARN_ON(num_maars % 2);
388 /* Configure the required MAARs */
389 used = platform_maar_init(num_maars / 2);
391 /* Disable any further MAARs */
392 for (i = (used * 2); i < num_maars; i++) {
394 back_to_back_c0_hazard();
396 back_to_back_c0_hazard();
400 void __init mem_init(void)
402 #ifdef CONFIG_HIGHMEM
403 #ifdef CONFIG_DISCONTIGMEM
404 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
406 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn;
408 max_mapnr = max_low_pfn;
410 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
414 setup_zero_pages(); /* Setup zeroed pages. */
415 mem_init_free_highmem();
416 mem_init_print_info(NULL);
419 if ((unsigned long) &_text > (unsigned long) CKSEG0)
420 /* The -4 is a hack so that user tools don't have to handle
422 kclist_add(&kcore_kseg0, (void *) CKSEG0,
423 0x80000000 - 4, KCORE_TEXT);
426 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
428 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
432 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
433 struct page *page = pfn_to_page(pfn);
434 void *addr = phys_to_virt(PFN_PHYS(pfn));
436 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
437 free_reserved_page(page);
439 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
442 #ifdef CONFIG_BLK_DEV_INITRD
443 void free_initrd_mem(unsigned long start, unsigned long end)
445 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
450 void (*free_init_pages_eva)(void *begin, void *end) = NULL;
452 void __init_refok free_initmem(void)
454 prom_free_prom_memory();
456 * Let the platform define a specific function to free the
457 * init section since EVA may have used any possible mapping
458 * between virtual and physical addresses.
460 if (free_init_pages_eva)
461 free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
463 free_initmem_default(POISON_FREE_INITMEM);
466 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
467 unsigned long pgd_current[NR_CPUS];
471 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
472 * are constants. So we use the variants from asm-offset.h until that gcc
473 * will officially be retired.
475 * Align swapper_pg_dir in to 64K, allows its address to be loaded
476 * with a single LUI instruction in the TLB handlers. If we used
477 * __aligned(64K), its size would get rounded up to the alignment
478 * size, and waste space. So we place it in its own section and align
479 * it in the linker script.
481 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(.bss..swapper_pg_dir);
482 #ifndef __PAGETABLE_PMD_FOLDED
483 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
485 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;