x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / powerpc / mm / pgtable_32.c
blob6c856fb8c15b01705fb6cf5ff28c0a232d85d3bd
1 /*
2 * This file contains the routines setting up the linux page tables.
3 * -- paulus
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>
25 #include <linux/mm.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>
35 #include <asm/io.h>
36 #include <asm/setup.h>
38 #include "mmu_decl.h"
40 unsigned long ioremap_base;
41 unsigned long ioremap_bot;
42 EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
44 #if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
45 #define HAVE_BATS 1
46 #endif
48 #if defined(CONFIG_FSL_BOOKE)
49 #define HAVE_TLBCAM 1
50 #endif
52 extern char etext[], _stext[];
54 #ifdef HAVE_BATS
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 */
65 #ifdef HAVE_TLBCAM
66 extern unsigned int tlbcam_index;
67 extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
68 extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
69 #else /* !HAVE_TLBCAM */
70 #define v_mapped_by_tlbcam(x) (0UL)
71 #define p_mapped_by_tlbcam(x) (0UL)
72 #endif /* HAVE_TLBCAM */
74 #define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
76 pgd_t *pgd_alloc(struct mm_struct *mm)
78 pgd_t *ret;
80 /* pgdir take page or two with 4K pages and a page fraction otherwise */
81 #ifndef CONFIG_PPC_4K_PAGES
82 ret = kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
83 #else
84 ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
85 PGDIR_ORDER - PAGE_SHIFT);
86 #endif
87 return ret;
90 void pgd_free(struct mm_struct *mm, pgd_t *pgd)
92 #ifndef CONFIG_PPC_4K_PAGES
93 kfree((void *)pgd);
94 #else
95 free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
96 #endif
99 __init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
101 pte_t *pte;
102 extern int mem_init_done;
103 extern void *early_get_page(void);
105 if (mem_init_done) {
106 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
107 } else {
108 pte = (pte_t *)early_get_page();
109 if (pte)
110 clear_page(pte);
112 return pte;
115 pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
117 struct page *ptepage;
119 gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
121 ptepage = alloc_pages(flags, 0);
122 if (!ptepage)
123 return NULL;
124 pgtable_page_ctor(ptepage);
125 return ptepage;
128 void __iomem *
129 ioremap(phys_addr_t addr, unsigned long size)
131 return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
132 __builtin_return_address(0));
134 EXPORT_SYMBOL(ioremap);
136 void __iomem *
137 ioremap_wc(phys_addr_t addr, unsigned long size)
139 return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
140 __builtin_return_address(0));
142 EXPORT_SYMBOL(ioremap_wc);
144 void __iomem *
145 ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
147 /* writeable implies dirty for kernel addresses */
148 if (flags & _PAGE_RW)
149 flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
151 /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
152 flags &= ~(_PAGE_USER | _PAGE_EXEC);
154 #ifdef _PAGE_BAP_SR
155 /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
156 * which means that we just cleared supervisor access... oops ;-) This
157 * restores it
159 flags |= _PAGE_BAP_SR;
160 #endif
162 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
164 EXPORT_SYMBOL(ioremap_prot);
166 void __iomem *
167 __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
169 return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
172 void __iomem *
173 __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
174 void *caller)
176 unsigned long v, i;
177 phys_addr_t p;
178 int err;
180 /* Make sure we have the base flags */
181 if ((flags & _PAGE_PRESENT) == 0)
182 flags |= PAGE_KERNEL;
184 /* Non-cacheable page cannot be coherent */
185 if (flags & _PAGE_NO_CACHE)
186 flags &= ~_PAGE_COHERENT;
189 * Choose an address to map it to.
190 * Once the vmalloc system is running, we use it.
191 * Before then, we use space going down from ioremap_base
192 * (ioremap_bot records where we're up to).
194 p = addr & PAGE_MASK;
195 size = PAGE_ALIGN(addr + size) - p;
198 * If the address lies within the first 16 MB, assume it's in ISA
199 * memory space
201 if (p < 16*1024*1024)
202 p += _ISA_MEM_BASE;
204 #ifndef CONFIG_CRASH_DUMP
206 * Don't allow anybody to remap normal RAM that we're using.
207 * mem_init() sets high_memory so only do the check after that.
209 if (mem_init_done && (p < virt_to_phys(high_memory)) &&
210 !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
211 printk("__ioremap(): phys addr 0x%llx is RAM lr %pf\n",
212 (unsigned long long)p, __builtin_return_address(0));
213 return NULL;
215 #endif
217 if (size == 0)
218 return NULL;
221 * Is it already mapped? Perhaps overlapped by a previous
222 * BAT mapping. If the whole area is mapped then we're done,
223 * otherwise remap it since we want to keep the virt addrs for
224 * each request contiguous.
226 * We make the assumption here that if the bottom and top
227 * of the range we want are mapped then it's mapped to the
228 * same virt address (and this is contiguous).
229 * -- Cort
231 if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
232 goto out;
234 if ((v = p_mapped_by_tlbcam(p)))
235 goto out;
237 if (mem_init_done) {
238 struct vm_struct *area;
239 area = get_vm_area_caller(size, VM_IOREMAP, caller);
240 if (area == 0)
241 return NULL;
242 area->phys_addr = p;
243 v = (unsigned long) area->addr;
244 } else {
245 v = (ioremap_bot -= size);
249 * Should check if it is a candidate for a BAT mapping
252 err = 0;
253 for (i = 0; i < size && err == 0; i += PAGE_SIZE)
254 err = map_page(v+i, p+i, flags);
255 if (err) {
256 if (mem_init_done)
257 vunmap((void *)v);
258 return NULL;
261 out:
262 return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
264 EXPORT_SYMBOL(__ioremap);
266 void iounmap(volatile void __iomem *addr)
269 * If mapped by BATs then there is nothing to do.
270 * Calling vfree() generates a benign warning.
272 if (v_mapped_by_bats((unsigned long)addr)) return;
274 if (addr > high_memory && (unsigned long) addr < ioremap_bot)
275 vunmap((void *) (PAGE_MASK & (unsigned long)addr));
277 EXPORT_SYMBOL(iounmap);
279 int map_page(unsigned long va, phys_addr_t pa, int flags)
281 pmd_t *pd;
282 pte_t *pg;
283 int err = -ENOMEM;
285 /* Use upper 10 bits of VA to index the first level map */
286 pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
287 /* Use middle 10 bits of VA to index the second-level map */
288 pg = pte_alloc_kernel(pd, va);
289 if (pg != 0) {
290 err = 0;
291 /* The PTE should never be already set nor present in the
292 * hash table
294 BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
295 flags);
296 set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
297 __pgprot(flags)));
299 return err;
303 * Map in a chunk of physical memory starting at start.
305 void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
307 unsigned long v, s, f;
308 phys_addr_t p;
309 int ktext;
311 s = offset;
312 v = PAGE_OFFSET + s;
313 p = memstart_addr + s;
314 for (; s < top; s += PAGE_SIZE) {
315 ktext = ((char *) v >= _stext && (char *) v < etext);
316 f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
317 map_page(v, p, f);
318 #ifdef CONFIG_PPC_STD_MMU_32
319 if (ktext)
320 hash_preload(&init_mm, v, 0, 0x300);
321 #endif
322 v += PAGE_SIZE;
323 p += PAGE_SIZE;
327 void __init mapin_ram(void)
329 unsigned long s, top;
331 #ifndef CONFIG_WII
332 top = total_lowmem;
333 s = mmu_mapin_ram(top);
334 __mapin_ram_chunk(s, top);
335 #else
336 if (!wii_hole_size) {
337 s = mmu_mapin_ram(total_lowmem);
338 __mapin_ram_chunk(s, total_lowmem);
339 } else {
340 top = wii_hole_start;
341 s = mmu_mapin_ram(top);
342 __mapin_ram_chunk(s, top);
344 top = memblock_end_of_DRAM();
345 s = wii_mmu_mapin_mem2(top);
346 __mapin_ram_chunk(s, top);
348 #endif
351 /* Scan the real Linux page tables and return a PTE pointer for
352 * a virtual address in a context.
353 * Returns true (1) if PTE was found, zero otherwise. The pointer to
354 * the PTE pointer is unmodified if PTE is not found.
357 get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
359 pgd_t *pgd;
360 pud_t *pud;
361 pmd_t *pmd;
362 pte_t *pte;
363 int retval = 0;
365 pgd = pgd_offset(mm, addr & PAGE_MASK);
366 if (pgd) {
367 pud = pud_offset(pgd, addr & PAGE_MASK);
368 if (pud && pud_present(*pud)) {
369 pmd = pmd_offset(pud, addr & PAGE_MASK);
370 if (pmd_present(*pmd)) {
371 pte = pte_offset_map(pmd, addr & PAGE_MASK);
372 if (pte) {
373 retval = 1;
374 *ptep = pte;
375 if (pmdp)
376 *pmdp = pmd;
377 /* XXX caller needs to do pte_unmap, yuck */
382 return(retval);
385 #ifdef CONFIG_DEBUG_PAGEALLOC
387 static int __change_page_attr(struct page *page, pgprot_t prot)
389 pte_t *kpte;
390 pmd_t *kpmd;
391 unsigned long address;
393 BUG_ON(PageHighMem(page));
394 address = (unsigned long)page_address(page);
396 if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
397 return 0;
398 if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
399 return -EINVAL;
400 __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
401 wmb();
402 flush_tlb_page(NULL, address);
403 pte_unmap(kpte);
405 return 0;
409 * Change the page attributes of an page in the linear mapping.
411 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
413 static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
415 int i, err = 0;
416 unsigned long flags;
418 local_irq_save(flags);
419 for (i = 0; i < numpages; i++, page++) {
420 err = __change_page_attr(page, prot);
421 if (err)
422 break;
424 local_irq_restore(flags);
425 return err;
429 void kernel_map_pages(struct page *page, int numpages, int enable)
431 if (PageHighMem(page))
432 return;
434 change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
436 #endif /* CONFIG_DEBUG_PAGEALLOC */
438 static int fixmaps;
440 void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
442 unsigned long address = __fix_to_virt(idx);
444 if (idx >= __end_of_fixed_addresses) {
445 BUG();
446 return;
449 map_page(address, phys, pgprot_val(flags));
450 fixmaps++;
453 void __this_fixmap_does_not_exist(void)
455 WARN_ON(1);