2 * This file contains the routines setting up the linux page tables.
5 * Derived from arch/ppc/mm/init.c:
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
8 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
9 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
10 * Copyright (C) 1996 Paul Mackerras
12 * Derived from "arch/i386/mm/init.c"
13 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/types.h>
26 #include <linux/vmalloc.h>
27 #include <linux/init.h>
28 #include <linux/highmem.h>
29 #include <linux/memblock.h>
30 #include <linux/slab.h>
32 #include <asm/pgtable.h>
33 #include <asm/pgalloc.h>
34 #include <asm/fixmap.h>
36 #include <asm/setup.h>
40 unsigned long ioremap_base;
41 unsigned long ioremap_bot;
42 EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
48 #if defined(CONFIG_FSL_BOOKE)
52 extern char etext[], _stext[];
55 extern phys_addr_t v_mapped_by_bats(unsigned long va);
56 extern unsigned long p_mapped_by_bats(phys_addr_t pa);
57 #else /* !HAVE_BATS */
58 #define v_mapped_by_bats(x) (0UL)
59 #define p_mapped_by_bats(x) (0UL)
60 #endif /* HAVE_BATS */
63 extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
64 extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
65 #else /* !HAVE_TLBCAM */
66 #define v_mapped_by_tlbcam(x) (0UL)
67 #define p_mapped_by_tlbcam(x) (0UL)
68 #endif /* HAVE_TLBCAM */
70 #define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
72 #ifndef CONFIG_PPC_4K_PAGES
73 static struct kmem_cache *pgtable_cache;
75 void pgtable_cache_init(void)
77 pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER,
78 1 << PGDIR_ORDER, 0, NULL);
79 if (pgtable_cache == NULL)
80 panic("Couldn't allocate pgtable caches");
84 pgd_t *pgd_alloc(struct mm_struct *mm)
88 /* pgdir take page or two with 4K pages and a page fraction otherwise */
89 #ifndef CONFIG_PPC_4K_PAGES
90 ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO);
92 ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
93 PGDIR_ORDER - PAGE_SHIFT);
98 void pgd_free(struct mm_struct *mm, pgd_t *pgd)
100 #ifndef CONFIG_PPC_4K_PAGES
101 kmem_cache_free(pgtable_cache, (void *)pgd);
103 free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
107 __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
110 extern int mem_init_done;
113 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
115 pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
122 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
124 struct page *ptepage;
126 gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
128 ptepage = alloc_pages(flags, 0);
131 if (!pgtable_page_ctor(ptepage)) {
132 __free_page(ptepage);
139 ioremap(phys_addr_t addr, unsigned long size)
141 return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
142 __builtin_return_address(0));
144 EXPORT_SYMBOL(ioremap);
147 ioremap_wc(phys_addr_t addr, unsigned long size)
149 return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
150 __builtin_return_address(0));
152 EXPORT_SYMBOL(ioremap_wc);
155 ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
157 /* writeable implies dirty for kernel addresses */
158 if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO)
159 flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
161 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
162 flags &= ~(_PAGE_USER | _PAGE_EXEC);
165 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
166 * which means that we just cleared supervisor access... oops ;-) This
169 flags |= _PAGE_BAP_SR;
172 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
174 EXPORT_SYMBOL(ioremap_prot);
177 __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
179 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
183 __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
190 /* Make sure we have the base flags */
191 if ((flags & _PAGE_PRESENT) == 0)
192 flags |= pgprot_val(PAGE_KERNEL);
194 /* Non-cacheable page cannot be coherent */
195 if (flags & _PAGE_NO_CACHE)
196 flags &= ~_PAGE_COHERENT;
199 * Choose an address to map it to.
200 * Once the vmalloc system is running, we use it.
201 * Before then, we use space going down from ioremap_base
202 * (ioremap_bot records where we're up to).
204 p = addr & PAGE_MASK;
205 size = PAGE_ALIGN(addr + size) - p;
208 * If the address lies within the first 16 MB, assume it's in ISA
211 if (p < 16*1024*1024)
214 #ifndef CONFIG_CRASH_DUMP
216 * Don't allow anybody to remap normal RAM that we're using.
217 * mem_init() sets high_memory so only do the check after that.
219 if (mem_init_done && (p < virt_to_phys(high_memory)) &&
220 !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
221 printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n",
222 (unsigned long long)p, __builtin_return_address(0));
231 * Is it already mapped? Perhaps overlapped by a previous
232 * BAT mapping. If the whole area is mapped then we're done,
233 * otherwise remap it since we want to keep the virt addrs for
234 * each request contiguous.
236 * We make the assumption here that if the bottom and top
237 * of the range we want are mapped then it's mapped to the
238 * same virt address (and this is contiguous).
241 if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
244 if ((v = p_mapped_by_tlbcam(p)))
248 struct vm_struct *area;
249 area = get_vm_area_caller(size, VM_IOREMAP, caller);
253 v = (unsigned long) area->addr;
255 v = (ioremap_bot -= size);
259 * Should check if it is a candidate for a BAT mapping
263 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
264 err = map_page(v+i, p+i, flags);
272 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
274 EXPORT_SYMBOL(__ioremap);
276 void iounmap(volatile void __iomem *addr)
279 * If mapped by BATs then there is nothing to do.
280 * Calling vfree() generates a benign warning.
282 if (v_mapped_by_bats((unsigned long)addr)) return;
284 if (addr > high_memory && (unsigned long) addr < ioremap_bot)
285 vunmap((void *) (PAGE_MASK & (unsigned long)addr));
287 EXPORT_SYMBOL(iounmap);
289 int map_page(unsigned long va, phys_addr_t pa, int flags)
295 /* Use upper 10 bits of VA to index the first level map */
296 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
297 /* Use middle 10 bits of VA to index the second-level map */
298 pg = pte_alloc_kernel(pd, va);
301 /* The PTE should never be already set nor present in the
304 BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
306 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
314 * Map in a chunk of physical memory starting at start.
316 void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
318 unsigned long v, s, f;
324 p = memstart_addr + s;
325 for (; s < top; s += PAGE_SIZE) {
326 ktext = ((char *) v >= _stext && (char *) v < etext);
327 f = ktext ? pgprot_val(PAGE_KERNEL_TEXT) : pgprot_val(PAGE_KERNEL);
329 #ifdef CONFIG_PPC_STD_MMU_32
331 hash_preload(&init_mm, v, 0, 0x300);
338 void __init mapin_ram(void)
340 unsigned long s, top;
344 s = mmu_mapin_ram(top);
345 __mapin_ram_chunk(s, top);
347 if (!wii_hole_size) {
348 s = mmu_mapin_ram(total_lowmem);
349 __mapin_ram_chunk(s, total_lowmem);
351 top = wii_hole_start;
352 s = mmu_mapin_ram(top);
353 __mapin_ram_chunk(s, top);
355 top = memblock_end_of_DRAM();
356 s = wii_mmu_mapin_mem2(top);
357 __mapin_ram_chunk(s, top);
362 /* Scan the real Linux page tables and return a PTE pointer for
363 * a virtual address in a context.
364 * Returns true (1) if PTE was found, zero otherwise. The pointer to
365 * the PTE pointer is unmodified if PTE is not found.
368 get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
376 pgd = pgd_offset(mm, addr & PAGE_MASK);
378 pud = pud_offset(pgd, addr & PAGE_MASK);
379 if (pud && pud_present(*pud)) {
380 pmd = pmd_offset(pud, addr & PAGE_MASK);
381 if (pmd_present(*pmd)) {
382 pte = pte_offset_map(pmd, addr & PAGE_MASK);
388 /* XXX caller needs to do pte_unmap, yuck */
396 #ifdef CONFIG_DEBUG_PAGEALLOC
398 static int __change_page_attr(struct page *page, pgprot_t prot)
402 unsigned long address;
404 BUG_ON(PageHighMem(page));
405 address = (unsigned long)page_address(page);
407 if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
409 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
411 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
413 flush_tlb_page(NULL, address);
420 * Change the page attributes of an page in the linear mapping.
422 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
424 static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
429 local_irq_save(flags);
430 for (i = 0; i < numpages; i++, page++) {
431 err = __change_page_attr(page, prot);
435 local_irq_restore(flags);
440 void __kernel_map_pages(struct page *page, int numpages, int enable)
442 if (PageHighMem(page))
445 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
447 #endif /* CONFIG_DEBUG_PAGEALLOC */
451 void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
453 unsigned long address = __fix_to_virt(idx);
455 if (idx >= __end_of_fixed_addresses) {
460 map_page(address, phys, pgprot_val(flags));
464 void __this_fixmap_does_not_exist(void)