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>
40 #include <asm/mmu_context.h>
41 #include <asm/sections.h>
42 #include <asm/pgtable.h>
43 #include <asm/pgalloc.h>
45 #include <asm/fixmap.h>
48 * We have up to 8 empty zeroed pages so we can map one of the right colour
49 * when needed. This is necessary only on R4000 / R4400 SC and MC versions
50 * where we have to avoid VCED / VECI exceptions for good performance at
51 * any price. Since page is never written to after the initialization we
52 * don't have to care about aliases on other CPUs.
54 unsigned long empty_zero_page, zero_page_mask;
55 EXPORT_SYMBOL_GPL(empty_zero_page);
56 EXPORT_SYMBOL(zero_page_mask);
59 * Not static inline because used by IP27 special magic initialization code
61 void setup_zero_pages(void)
63 unsigned int order, i;
71 empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
73 panic("Oh boy, that early out of memory?");
75 page = virt_to_page((void *)empty_zero_page);
76 split_page(page, order);
77 for (i = 0; i < (1 << order); i++, page++)
78 mark_page_reserved(page);
80 zero_page_mask = ((PAGE_SIZE << order) - 1) & PAGE_MASK;
83 static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot)
85 enum fixed_addresses idx;
86 unsigned long vaddr, flags, entrylo;
87 unsigned long old_ctx;
91 BUG_ON(Page_dcache_dirty(page));
94 idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
95 idx += in_interrupt() ? FIX_N_COLOURS : 0;
96 vaddr = __fix_to_virt(FIX_CMAP_END - idx);
97 pte = mk_pte(page, prot);
98 #if defined(CONFIG_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
99 entrylo = pte_to_entrylo(pte.pte_high);
101 entrylo = pte_to_entrylo(pte_val(pte));
104 local_irq_save(flags);
105 old_ctx = read_c0_entryhi();
106 write_c0_entryhi(vaddr & (PAGE_MASK << 1));
107 write_c0_entrylo0(entrylo);
108 write_c0_entrylo1(entrylo);
110 entrylo = (pte.pte_low & _PFNX_MASK);
111 writex_c0_entrylo0(entrylo);
112 writex_c0_entrylo1(entrylo);
114 tlbidx = read_c0_wired();
115 write_c0_wired(tlbidx + 1);
116 write_c0_index(tlbidx);
120 write_c0_entryhi(old_ctx);
121 local_irq_restore(flags);
123 return (void*) vaddr;
126 void *kmap_coherent(struct page *page, unsigned long addr)
128 return __kmap_pgprot(page, addr, PAGE_KERNEL);
131 void *kmap_noncoherent(struct page *page, unsigned long addr)
133 return __kmap_pgprot(page, addr, PAGE_KERNEL_NC);
136 void kunmap_coherent(void)
139 unsigned long flags, old_ctx;
141 local_irq_save(flags);
142 old_ctx = read_c0_entryhi();
143 wired = read_c0_wired() - 1;
144 write_c0_wired(wired);
145 write_c0_index(wired);
146 write_c0_entryhi(UNIQUE_ENTRYHI(wired));
147 write_c0_entrylo0(0);
148 write_c0_entrylo1(0);
152 write_c0_entryhi(old_ctx);
153 local_irq_restore(flags);
157 void copy_user_highpage(struct page *to, struct page *from,
158 unsigned long vaddr, struct vm_area_struct *vma)
162 vto = kmap_atomic(to);
163 if (cpu_has_dc_aliases &&
164 page_mapped(from) && !Page_dcache_dirty(from)) {
165 vfrom = kmap_coherent(from, vaddr);
166 copy_page(vto, vfrom);
169 vfrom = kmap_atomic(from);
170 copy_page(vto, vfrom);
171 kunmap_atomic(vfrom);
173 if ((!cpu_has_ic_fills_f_dc) ||
174 pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
175 flush_data_cache_page((unsigned long)vto);
177 /* Make sure this page is cleared on other CPU's too before using it */
181 void copy_to_user_page(struct vm_area_struct *vma,
182 struct page *page, unsigned long vaddr, void *dst, const void *src,
185 if (cpu_has_dc_aliases &&
186 page_mapped(page) && !Page_dcache_dirty(page)) {
187 void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
188 memcpy(vto, src, len);
191 memcpy(dst, src, len);
192 if (cpu_has_dc_aliases)
193 SetPageDcacheDirty(page);
195 if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
196 flush_cache_page(vma, vaddr, page_to_pfn(page));
199 void copy_from_user_page(struct vm_area_struct *vma,
200 struct page *page, unsigned long vaddr, void *dst, const void *src,
203 if (cpu_has_dc_aliases &&
204 page_mapped(page) && !Page_dcache_dirty(page)) {
205 void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
206 memcpy(dst, vfrom, len);
209 memcpy(dst, src, len);
210 if (cpu_has_dc_aliases)
211 SetPageDcacheDirty(page);
214 EXPORT_SYMBOL_GPL(copy_from_user_page);
216 void __init fixrange_init(unsigned long start, unsigned long end,
219 #ifdef CONFIG_HIGHMEM
228 i = __pgd_offset(vaddr);
229 j = __pud_offset(vaddr);
230 k = __pmd_offset(vaddr);
233 for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
235 for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
237 for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) {
238 if (pmd_none(*pmd)) {
239 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
240 set_pmd(pmd, __pmd((unsigned long)pte));
241 BUG_ON(pte != pte_offset_kernel(pmd, 0));
252 #ifndef CONFIG_NEED_MULTIPLE_NODES
253 int page_is_ram(unsigned long pagenr)
257 for (i = 0; i < boot_mem_map.nr_map; i++) {
258 unsigned long addr, end;
260 switch (boot_mem_map.map[i].type) {
262 case BOOT_MEM_INIT_RAM:
265 /* not usable memory */
269 addr = PFN_UP(boot_mem_map.map[i].addr);
270 end = PFN_DOWN(boot_mem_map.map[i].addr +
271 boot_mem_map.map[i].size);
273 if (pagenr >= addr && pagenr < end)
280 void __init paging_init(void)
282 unsigned long max_zone_pfns[MAX_NR_ZONES];
283 unsigned long lastpfn __maybe_unused;
287 #ifdef CONFIG_HIGHMEM
290 #ifdef CONFIG_ZONE_DMA
291 max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
293 #ifdef CONFIG_ZONE_DMA32
294 max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
296 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
297 lastpfn = max_low_pfn;
298 #ifdef CONFIG_HIGHMEM
299 max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
300 lastpfn = highend_pfn;
302 if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
303 printk(KERN_WARNING "This processor doesn't support highmem."
304 " %ldk highmem ignored\n",
305 (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
306 max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
307 lastpfn = max_low_pfn;
311 free_area_init_nodes(max_zone_pfns);
315 static struct kcore_list kcore_kseg0;
318 static inline void mem_init_free_highmem(void)
320 #ifdef CONFIG_HIGHMEM
323 for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
324 struct page *page = pfn_to_page(tmp);
326 if (!page_is_ram(tmp))
327 SetPageReserved(page);
329 free_highmem_page(page);
334 unsigned __weak platform_maar_init(unsigned num_maars)
339 static void maar_init(void)
341 unsigned num_maars, used, i;
346 /* Detect the number of MAARs */
348 back_to_back_c0_hazard();
349 num_maars = read_c0_maari() + 1;
351 /* MAARs should be in pairs */
352 WARN_ON(num_maars % 2);
354 /* Configure the required MAARs */
355 used = platform_maar_init(num_maars / 2);
357 /* Disable any further MAARs */
358 for (i = (used * 2); i < num_maars; i++) {
360 back_to_back_c0_hazard();
362 back_to_back_c0_hazard();
366 void __init mem_init(void)
368 #ifdef CONFIG_HIGHMEM
369 #ifdef CONFIG_DISCONTIGMEM
370 #error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
372 max_mapnr = highend_pfn ? highend_pfn : max_low_pfn;
374 max_mapnr = max_low_pfn;
376 high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
380 setup_zero_pages(); /* Setup zeroed pages. */
381 mem_init_free_highmem();
382 mem_init_print_info(NULL);
385 if ((unsigned long) &_text > (unsigned long) CKSEG0)
386 /* The -4 is a hack so that user tools don't have to handle
388 kclist_add(&kcore_kseg0, (void *) CKSEG0,
389 0x80000000 - 4, KCORE_TEXT);
392 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
394 void free_init_pages(const char *what, unsigned long begin, unsigned long end)
398 for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
399 struct page *page = pfn_to_page(pfn);
400 void *addr = phys_to_virt(PFN_PHYS(pfn));
402 memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
403 free_reserved_page(page);
405 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
408 #ifdef CONFIG_BLK_DEV_INITRD
409 void free_initrd_mem(unsigned long start, unsigned long end)
411 free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
416 void (*free_init_pages_eva)(void *begin, void *end) = NULL;
418 void __init_refok free_initmem(void)
420 prom_free_prom_memory();
422 * Let the platform define a specific function to free the
423 * init section since EVA may have used any possible mapping
424 * between virtual and physical addresses.
426 if (free_init_pages_eva)
427 free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
429 free_initmem_default(POISON_FREE_INITMEM);
432 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
433 unsigned long pgd_current[NR_CPUS];
437 * gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
438 * are constants. So we use the variants from asm-offset.h until that gcc
439 * will officially be retired.
441 * Align swapper_pg_dir in to 64K, allows its address to be loaded
442 * with a single LUI instruction in the TLB handlers. If we used
443 * __aligned(64K), its size would get rounded up to the alignment
444 * size, and waste space. So we place it in its own section and align
445 * it in the linker script.
447 pgd_t swapper_pg_dir[_PTRS_PER_PGD] __section(.bss..swapper_pg_dir);
448 #ifndef __PAGETABLE_PMD_FOLDED
449 pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned_bss;
451 pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;