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 void setbat(int index, unsigned long virt, phys_addr_t phys,
58 unsigned int size, int flags);
60 #else /* !HAVE_BATS */
61 #define v_mapped_by_bats(x) (0UL)
62 #define p_mapped_by_bats(x) (0UL)
63 #endif /* HAVE_BATS */
66 extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
67 extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
68 #else /* !HAVE_TLBCAM */
69 #define v_mapped_by_tlbcam(x) (0UL)
70 #define p_mapped_by_tlbcam(x) (0UL)
71 #endif /* HAVE_TLBCAM */
73 #define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
75 #ifndef CONFIG_PPC_4K_PAGES
76 static struct kmem_cache *pgtable_cache;
78 void pgtable_cache_init(void)
80 pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER,
81 1 << PGDIR_ORDER, 0, NULL);
82 if (pgtable_cache == NULL)
83 panic("Couldn't allocate pgtable caches");
87 pgd_t *pgd_alloc(struct mm_struct *mm)
91 /* pgdir take page or two with 4K pages and a page fraction otherwise */
92 #ifndef CONFIG_PPC_4K_PAGES
93 ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO);
95 ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
96 PGDIR_ORDER - PAGE_SHIFT);
101 void pgd_free(struct mm_struct *mm, pgd_t *pgd)
103 #ifndef CONFIG_PPC_4K_PAGES
104 kmem_cache_free(pgtable_cache, (void *)pgd);
106 free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
110 __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
113 extern int mem_init_done;
116 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
118 pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
125 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
127 struct page *ptepage;
129 gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
131 ptepage = alloc_pages(flags, 0);
134 if (!pgtable_page_ctor(ptepage)) {
135 __free_page(ptepage);
142 ioremap(phys_addr_t addr, unsigned long size)
144 return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
145 __builtin_return_address(0));
147 EXPORT_SYMBOL(ioremap);
150 ioremap_wc(phys_addr_t addr, unsigned long size)
152 return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
153 __builtin_return_address(0));
155 EXPORT_SYMBOL(ioremap_wc);
158 ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
160 /* writeable implies dirty for kernel addresses */
161 if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO)
162 flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
164 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
165 flags &= ~(_PAGE_USER | _PAGE_EXEC);
168 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
169 * which means that we just cleared supervisor access... oops ;-) This
172 flags |= _PAGE_BAP_SR;
175 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
177 EXPORT_SYMBOL(ioremap_prot);
180 __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
182 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
186 __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
193 /* Make sure we have the base flags */
194 if ((flags & _PAGE_PRESENT) == 0)
195 flags |= PAGE_KERNEL;
197 /* Non-cacheable page cannot be coherent */
198 if (flags & _PAGE_NO_CACHE)
199 flags &= ~_PAGE_COHERENT;
202 * Choose an address to map it to.
203 * Once the vmalloc system is running, we use it.
204 * Before then, we use space going down from ioremap_base
205 * (ioremap_bot records where we're up to).
207 p = addr & PAGE_MASK;
208 size = PAGE_ALIGN(addr + size) - p;
211 * If the address lies within the first 16 MB, assume it's in ISA
214 if (p < 16*1024*1024)
217 #ifndef CONFIG_CRASH_DUMP
219 * Don't allow anybody to remap normal RAM that we're using.
220 * mem_init() sets high_memory so only do the check after that.
222 if (mem_init_done && (p < virt_to_phys(high_memory)) &&
223 !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
224 printk("__ioremap(): phys addr 0x%llx is RAM lr %pf\n",
225 (unsigned long long)p, __builtin_return_address(0));
234 * Is it already mapped? Perhaps overlapped by a previous
235 * BAT mapping. If the whole area is mapped then we're done,
236 * otherwise remap it since we want to keep the virt addrs for
237 * each request contiguous.
239 * We make the assumption here that if the bottom and top
240 * of the range we want are mapped then it's mapped to the
241 * same virt address (and this is contiguous).
244 if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
247 if ((v = p_mapped_by_tlbcam(p)))
251 struct vm_struct *area;
252 area = get_vm_area_caller(size, VM_IOREMAP, caller);
256 v = (unsigned long) area->addr;
258 v = (ioremap_bot -= size);
262 * Should check if it is a candidate for a BAT mapping
266 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
267 err = map_page(v+i, p+i, flags);
275 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
277 EXPORT_SYMBOL(__ioremap);
279 void iounmap(volatile void __iomem *addr)
282 * If mapped by BATs then there is nothing to do.
283 * Calling vfree() generates a benign warning.
285 if (v_mapped_by_bats((unsigned long)addr)) return;
287 if (addr > high_memory && (unsigned long) addr < ioremap_bot)
288 vunmap((void *) (PAGE_MASK & (unsigned long)addr));
290 EXPORT_SYMBOL(iounmap);
292 int map_page(unsigned long va, phys_addr_t pa, int flags)
298 /* Use upper 10 bits of VA to index the first level map */
299 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
300 /* Use middle 10 bits of VA to index the second-level map */
301 pg = pte_alloc_kernel(pd, va);
304 /* The PTE should never be already set nor present in the
307 BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
309 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
317 * Map in a chunk of physical memory starting at start.
319 void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
321 unsigned long v, s, f;
327 p = memstart_addr + s;
328 for (; s < top; s += PAGE_SIZE) {
329 ktext = ((char *) v >= _stext && (char *) v < etext);
330 f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
332 #ifdef CONFIG_PPC_STD_MMU_32
334 hash_preload(&init_mm, v, 0, 0x300);
341 void __init mapin_ram(void)
343 unsigned long s, top;
347 s = mmu_mapin_ram(top);
348 __mapin_ram_chunk(s, top);
350 if (!wii_hole_size) {
351 s = mmu_mapin_ram(total_lowmem);
352 __mapin_ram_chunk(s, total_lowmem);
354 top = wii_hole_start;
355 s = mmu_mapin_ram(top);
356 __mapin_ram_chunk(s, top);
358 top = memblock_end_of_DRAM();
359 s = wii_mmu_mapin_mem2(top);
360 __mapin_ram_chunk(s, top);
365 /* Scan the real Linux page tables and return a PTE pointer for
366 * a virtual address in a context.
367 * Returns true (1) if PTE was found, zero otherwise. The pointer to
368 * the PTE pointer is unmodified if PTE is not found.
371 get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
379 pgd = pgd_offset(mm, addr & PAGE_MASK);
381 pud = pud_offset(pgd, addr & PAGE_MASK);
382 if (pud && pud_present(*pud)) {
383 pmd = pmd_offset(pud, addr & PAGE_MASK);
384 if (pmd_present(*pmd)) {
385 pte = pte_offset_map(pmd, addr & PAGE_MASK);
391 /* XXX caller needs to do pte_unmap, yuck */
399 #ifdef CONFIG_DEBUG_PAGEALLOC
401 static int __change_page_attr(struct page *page, pgprot_t prot)
405 unsigned long address;
407 BUG_ON(PageHighMem(page));
408 address = (unsigned long)page_address(page);
410 if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
412 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
414 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
416 flush_tlb_page(NULL, address);
423 * Change the page attributes of an page in the linear mapping.
425 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
427 static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
432 local_irq_save(flags);
433 for (i = 0; i < numpages; i++, page++) {
434 err = __change_page_attr(page, prot);
438 local_irq_restore(flags);
443 void __kernel_map_pages(struct page *page, int numpages, int enable)
445 if (PageHighMem(page))
448 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
450 #endif /* CONFIG_DEBUG_PAGEALLOC */
454 void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
456 unsigned long address = __fix_to_virt(idx);
458 if (idx >= __end_of_fixed_addresses) {
463 map_page(address, phys, pgprot_val(flags));
467 void __this_fixmap_does_not_exist(void)