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1/*
2 * Re-map IO memory to kernel address space so that we can access it.
3 * This is needed for high PCI addresses that aren't mapped in the
4 * 640k-1MB IO memory area on PC's
5 *
6 * (C) Copyright 1995 1996 Linus Torvalds
7 */
8
9#include <linux/bootmem.h>
10#include <linux/init.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/vmalloc.h>
15#include <linux/mmiotrace.h>
16
17#include <asm/cacheflush.h>
18#include <asm/e820.h>
19#include <asm/fixmap.h>
20#include <asm/pgtable.h>
21#include <asm/tlbflush.h>
22#include <asm/pgalloc.h>
23#include <asm/pat.h>
24
25#include "physaddr.h"
26
27/*
28 * Fix up the linear direct mapping of the kernel to avoid cache attribute
29 * conflicts.
30 */
31int ioremap_change_attr(unsigned long vaddr, unsigned long size,
32 unsigned long prot_val)
33{
34 unsigned long nrpages = size >> PAGE_SHIFT;
35 int err;
36
37 switch (prot_val) {
38 case _PAGE_CACHE_UC:
39 default:
40 err = _set_memory_uc(vaddr, nrpages);
41 break;
42 case _PAGE_CACHE_WC:
43 err = _set_memory_wc(vaddr, nrpages);
44 break;
45 case _PAGE_CACHE_WB:
46 err = _set_memory_wb(vaddr, nrpages);
47 break;
48 }
49
50 return err;
51}
52
53/*
54 * Remap an arbitrary physical address space into the kernel virtual
55 * address space. Needed when the kernel wants to access high addresses
56 * directly.
57 *
58 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
59 * have to convert them into an offset in a page-aligned mapping, but the
60 * caller shouldn't need to know that small detail.
61 */
62static void __iomem *__ioremap_caller(resource_size_t phys_addr,
63 unsigned long size, unsigned long prot_val, void *caller)
64{
65 unsigned long offset, vaddr;
66 resource_size_t pfn, last_pfn, last_addr;
67 const resource_size_t unaligned_phys_addr = phys_addr;
68 const unsigned long unaligned_size = size;
69 struct vm_struct *area;
70 unsigned long new_prot_val;
71 pgprot_t prot;
72 int retval;
73 void __iomem *ret_addr;
74
75 /* Don't allow wraparound or zero size */
76 last_addr = phys_addr + size - 1;
77 if (!size || last_addr < phys_addr)
78 return NULL;
79
80 if (!phys_addr_valid(phys_addr)) {
81 printk(KERN_WARNING "ioremap: invalid physical address %llx\n",
82 (unsigned long long)phys_addr);
83 WARN_ON_ONCE(1);
84 return NULL;
85 }
86
87 /*
88 * Don't remap the low PCI/ISA area, it's always mapped..
89 */
90 if (is_ISA_range(phys_addr, last_addr))
91 return (__force void __iomem *)phys_to_virt(phys_addr);
92
93 /*
94 * Don't allow anybody to remap normal RAM that we're using..
95 */
96 last_pfn = last_addr >> PAGE_SHIFT;
97 for (pfn = phys_addr >> PAGE_SHIFT; pfn <= last_pfn; pfn++) {
98 int is_ram = page_is_ram(pfn);
99
100 if (is_ram && pfn_valid(pfn) && !PageReserved(pfn_to_page(pfn)))
101 return NULL;
102 WARN_ON_ONCE(is_ram);
103 }
104
105 /*
106 * Mappings have to be page-aligned
107 */
108 offset = phys_addr & ~PAGE_MASK;
109 phys_addr &= PHYSICAL_PAGE_MASK;
110 size = PAGE_ALIGN(last_addr+1) - phys_addr;
111
112 retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
113 prot_val, &new_prot_val);
114 if (retval) {
115 printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
116 return NULL;
117 }
118
119 if (prot_val != new_prot_val) {
120 if (!is_new_memtype_allowed(phys_addr, size,
121 prot_val, new_prot_val)) {
122 printk(KERN_ERR
123 "ioremap error for 0x%llx-0x%llx, requested 0x%lx, got 0x%lx\n",
124 (unsigned long long)phys_addr,
125 (unsigned long long)(phys_addr + size),
126 prot_val, new_prot_val);
127 goto err_free_memtype;
128 }
129 prot_val = new_prot_val;
130 }
131
132 switch (prot_val) {
133 case _PAGE_CACHE_UC:
134 default:
135 prot = PAGE_KERNEL_IO_NOCACHE;
136 break;
137 case _PAGE_CACHE_UC_MINUS:
138 prot = PAGE_KERNEL_IO_UC_MINUS;
139 break;
140 case _PAGE_CACHE_WC:
141 prot = PAGE_KERNEL_IO_WC;
142 break;
143 case _PAGE_CACHE_WB:
144 prot = PAGE_KERNEL_IO;
145 break;
146 }
147
148 /*
149 * Ok, go for it..
150 */
151 area = get_vm_area_caller(size, VM_IOREMAP, caller);
152 if (!area)
153 goto err_free_memtype;
154 area->phys_addr = phys_addr;
155 vaddr = (unsigned long) area->addr;
156
157 if (kernel_map_sync_memtype(phys_addr, size, prot_val))
158 goto err_free_area;
159
160 if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot))
161 goto err_free_area;
162
163 ret_addr = (void __iomem *) (vaddr + offset);
164 mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);
165
166 /*
167 * Check if the request spans more than any BAR in the iomem resource
168 * tree.
169 */
170 WARN_ONCE(iomem_map_sanity_check(unaligned_phys_addr, unaligned_size),
171 KERN_INFO "Info: mapping multiple BARs. Your kernel is fine.");
172
173 return ret_addr;
174err_free_area:
175 free_vm_area(area);
176err_free_memtype:
177 free_memtype(phys_addr, phys_addr + size);
178 return NULL;
179}
180
181/**
182 * ioremap_nocache - map bus memory into CPU space
183 * @phys_addr: bus address of the memory
184 * @size: size of the resource to map
185 *
186 * ioremap_nocache performs a platform specific sequence of operations to
187 * make bus memory CPU accessible via the readb/readw/readl/writeb/
188 * writew/writel functions and the other mmio helpers. The returned
189 * address is not guaranteed to be usable directly as a virtual
190 * address.
191 *
192 * This version of ioremap ensures that the memory is marked uncachable
193 * on the CPU as well as honouring existing caching rules from things like
194 * the PCI bus. Note that there are other caches and buffers on many
195 * busses. In particular driver authors should read up on PCI writes
196 *
197 * It's useful if some control registers are in such an area and
198 * write combining or read caching is not desirable:
199 *
200 * Must be freed with iounmap.
201 */
202void __iomem *ioremap_nocache(resource_size_t phys_addr, unsigned long size)
203{
204 /*
205 * Ideally, this should be:
206 * pat_enabled ? _PAGE_CACHE_UC : _PAGE_CACHE_UC_MINUS;
207 *
208 * Till we fix all X drivers to use ioremap_wc(), we will use
209 * UC MINUS.
210 */
211 unsigned long val = _PAGE_CACHE_UC_MINUS;
212
213 return __ioremap_caller(phys_addr, size, val,
214 __builtin_return_address(0));
215}
216EXPORT_SYMBOL(ioremap_nocache);
217
218/**
219 * ioremap_wc - map memory into CPU space write combined
220 * @phys_addr: bus address of the memory
221 * @size: size of the resource to map
222 *
223 * This version of ioremap ensures that the memory is marked write combining.
224 * Write combining allows faster writes to some hardware devices.
225 *
226 * Must be freed with iounmap.
227 */
228void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
229{
230 if (pat_enabled)
231 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_WC,
232 __builtin_return_address(0));
233 else
234 return ioremap_nocache(phys_addr, size);
235}
236EXPORT_SYMBOL(ioremap_wc);
237
238void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
239{
240 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_WB,
241 __builtin_return_address(0));
242}
243EXPORT_SYMBOL(ioremap_cache);
244
245void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
246 unsigned long prot_val)
247{
248 return __ioremap_caller(phys_addr, size, (prot_val & _PAGE_CACHE_MASK),
249 __builtin_return_address(0));
250}
251EXPORT_SYMBOL(ioremap_prot);
252
253/**
254 * iounmap - Free a IO remapping
255 * @addr: virtual address from ioremap_*
256 *
257 * Caller must ensure there is only one unmapping for the same pointer.
258 */
259void iounmap(volatile void __iomem *addr)
260{
261 struct vm_struct *p, *o;
262
263 if ((void __force *)addr <= high_memory)
264 return;
265
266 /*
267 * __ioremap special-cases the PCI/ISA range by not instantiating a
268 * vm_area and by simply returning an address into the kernel mapping
269 * of ISA space. So handle that here.
270 */
271 if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) &&
272 (void __force *)addr < phys_to_virt(ISA_END_ADDRESS))
273 return;
274
275 addr = (volatile void __iomem *)
276 (PAGE_MASK & (unsigned long __force)addr);
277
278 mmiotrace_iounmap(addr);
279
280 /* Use the vm area unlocked, assuming the caller
281 ensures there isn't another iounmap for the same address
282 in parallel. Reuse of the virtual address is prevented by
283 leaving it in the global lists until we're done with it.
284 cpa takes care of the direct mappings. */
285 p = find_vm_area((void __force *)addr);
286
287 if (!p) {
288 printk(KERN_ERR "iounmap: bad address %p\n", addr);
289 dump_stack();
290 return;
291 }
292
293 free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p));
294
295 /* Finally remove it */
296 o = remove_vm_area((void __force *)addr);
297 BUG_ON(p != o || o == NULL);
298 kfree(p);
299}
300EXPORT_SYMBOL(iounmap);
301
302/*
303 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
304 * access
305 */
306void *xlate_dev_mem_ptr(unsigned long phys)
307{
308 void *addr;
309 unsigned long start = phys & PAGE_MASK;
310
311 /* If page is RAM, we can use __va. Otherwise ioremap and unmap. */
312 if (page_is_ram(start >> PAGE_SHIFT))
313 return __va(phys);
314
315 addr = (void __force *)ioremap_cache(start, PAGE_SIZE);
316 if (addr)
317 addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));
318
319 return addr;
320}
321
322void unxlate_dev_mem_ptr(unsigned long phys, void *addr)
323{
324 if (page_is_ram(phys >> PAGE_SHIFT))
325 return;
326
327 iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK));
328 return;
329}
330
331static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;
332
333static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
334{
335 /* Don't assume we're using swapper_pg_dir at this point */
336 pgd_t *base = __va(read_cr3());
337 pgd_t *pgd = &base[pgd_index(addr)];
338 pud_t *pud = pud_offset(pgd, addr);
339 pmd_t *pmd = pmd_offset(pud, addr);
340
341 return pmd;
342}
343
344static inline pte_t * __init early_ioremap_pte(unsigned long addr)
345{
346 return &bm_pte[pte_index(addr)];
347}
348
349bool __init is_early_ioremap_ptep(pte_t *ptep)
350{
351 return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)];
352}
353
354void __init early_ioremap_init(void)
355{
356 pmd_t *pmd;
357
358 early_ioremap_setup();
359
360 pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
361 memset(bm_pte, 0, sizeof(bm_pte));
362 pmd_populate_kernel(&init_mm, pmd, bm_pte);
363
364 /*
365 * The boot-ioremap range spans multiple pmds, for which
366 * we are not prepared:
367 */
368#define __FIXADDR_TOP (-PAGE_SIZE)
369 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
370 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
371#undef __FIXADDR_TOP
372 if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
373 WARN_ON(1);
374 printk(KERN_WARNING "pmd %p != %p\n",
375 pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
376 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
377 fix_to_virt(FIX_BTMAP_BEGIN));
378 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END): %08lx\n",
379 fix_to_virt(FIX_BTMAP_END));
380
381 printk(KERN_WARNING "FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
382 printk(KERN_WARNING "FIX_BTMAP_BEGIN: %d\n",
383 FIX_BTMAP_BEGIN);
384 }
385}
386
387void __init __early_set_fixmap(enum fixed_addresses idx,
388 phys_addr_t phys, pgprot_t flags)
389{
390 unsigned long addr = __fix_to_virt(idx);
391 pte_t *pte;
392
393 if (idx >= __end_of_fixed_addresses) {
394 BUG();
395 return;
396 }
397 pte = early_ioremap_pte(addr);
398
399 if (pgprot_val(flags))
400 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
401 else
402 pte_clear(&init_mm, addr, pte);
403 __flush_tlb_one(addr);
404}
1/*
2 * Re-map IO memory to kernel address space so that we can access it.
3 * This is needed for high PCI addresses that aren't mapped in the
4 * 640k-1MB IO memory area on PC's
5 *
6 * (C) Copyright 1995 1996 Linus Torvalds
7 */
8
9#include <linux/bootmem.h>
10#include <linux/init.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/vmalloc.h>
15#include <linux/mmiotrace.h>
16
17#include <asm/cacheflush.h>
18#include <asm/e820.h>
19#include <asm/fixmap.h>
20#include <asm/pgtable.h>
21#include <asm/tlbflush.h>
22#include <asm/pgalloc.h>
23#include <asm/pat.h>
24
25#include "physaddr.h"
26
27/*
28 * Fix up the linear direct mapping of the kernel to avoid cache attribute
29 * conflicts.
30 */
31int ioremap_change_attr(unsigned long vaddr, unsigned long size,
32 enum page_cache_mode pcm)
33{
34 unsigned long nrpages = size >> PAGE_SHIFT;
35 int err;
36
37 switch (pcm) {
38 case _PAGE_CACHE_MODE_UC:
39 default:
40 err = _set_memory_uc(vaddr, nrpages);
41 break;
42 case _PAGE_CACHE_MODE_WC:
43 err = _set_memory_wc(vaddr, nrpages);
44 break;
45 case _PAGE_CACHE_MODE_WT:
46 err = _set_memory_wt(vaddr, nrpages);
47 break;
48 case _PAGE_CACHE_MODE_WB:
49 err = _set_memory_wb(vaddr, nrpages);
50 break;
51 }
52
53 return err;
54}
55
56static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
57 void *arg)
58{
59 unsigned long i;
60
61 for (i = 0; i < nr_pages; ++i)
62 if (pfn_valid(start_pfn + i) &&
63 !PageReserved(pfn_to_page(start_pfn + i)))
64 return 1;
65
66 return 0;
67}
68
69/*
70 * Remap an arbitrary physical address space into the kernel virtual
71 * address space. It transparently creates kernel huge I/O mapping when
72 * the physical address is aligned by a huge page size (1GB or 2MB) and
73 * the requested size is at least the huge page size.
74 *
75 * NOTE: MTRRs can override PAT memory types with a 4KB granularity.
76 * Therefore, the mapping code falls back to use a smaller page toward 4KB
77 * when a mapping range is covered by non-WB type of MTRRs.
78 *
79 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
80 * have to convert them into an offset in a page-aligned mapping, but the
81 * caller shouldn't need to know that small detail.
82 */
83static void __iomem *__ioremap_caller(resource_size_t phys_addr,
84 unsigned long size, enum page_cache_mode pcm, void *caller)
85{
86 unsigned long offset, vaddr;
87 resource_size_t pfn, last_pfn, last_addr;
88 const resource_size_t unaligned_phys_addr = phys_addr;
89 const unsigned long unaligned_size = size;
90 struct vm_struct *area;
91 enum page_cache_mode new_pcm;
92 pgprot_t prot;
93 int retval;
94 void __iomem *ret_addr;
95
96 /* Don't allow wraparound or zero size */
97 last_addr = phys_addr + size - 1;
98 if (!size || last_addr < phys_addr)
99 return NULL;
100
101 if (!phys_addr_valid(phys_addr)) {
102 printk(KERN_WARNING "ioremap: invalid physical address %llx\n",
103 (unsigned long long)phys_addr);
104 WARN_ON_ONCE(1);
105 return NULL;
106 }
107
108 /*
109 * Don't remap the low PCI/ISA area, it's always mapped..
110 */
111 if (is_ISA_range(phys_addr, last_addr))
112 return (__force void __iomem *)phys_to_virt(phys_addr);
113
114 /*
115 * Don't allow anybody to remap normal RAM that we're using..
116 */
117 pfn = phys_addr >> PAGE_SHIFT;
118 last_pfn = last_addr >> PAGE_SHIFT;
119 if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
120 __ioremap_check_ram) == 1) {
121 WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
122 &phys_addr, &last_addr);
123 return NULL;
124 }
125
126 /*
127 * Mappings have to be page-aligned
128 */
129 offset = phys_addr & ~PAGE_MASK;
130 phys_addr &= PHYSICAL_PAGE_MASK;
131 size = PAGE_ALIGN(last_addr+1) - phys_addr;
132
133 retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
134 pcm, &new_pcm);
135 if (retval) {
136 printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
137 return NULL;
138 }
139
140 if (pcm != new_pcm) {
141 if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) {
142 printk(KERN_ERR
143 "ioremap error for 0x%llx-0x%llx, requested 0x%x, got 0x%x\n",
144 (unsigned long long)phys_addr,
145 (unsigned long long)(phys_addr + size),
146 pcm, new_pcm);
147 goto err_free_memtype;
148 }
149 pcm = new_pcm;
150 }
151
152 prot = PAGE_KERNEL_IO;
153 switch (pcm) {
154 case _PAGE_CACHE_MODE_UC:
155 default:
156 prot = __pgprot(pgprot_val(prot) |
157 cachemode2protval(_PAGE_CACHE_MODE_UC));
158 break;
159 case _PAGE_CACHE_MODE_UC_MINUS:
160 prot = __pgprot(pgprot_val(prot) |
161 cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS));
162 break;
163 case _PAGE_CACHE_MODE_WC:
164 prot = __pgprot(pgprot_val(prot) |
165 cachemode2protval(_PAGE_CACHE_MODE_WC));
166 break;
167 case _PAGE_CACHE_MODE_WT:
168 prot = __pgprot(pgprot_val(prot) |
169 cachemode2protval(_PAGE_CACHE_MODE_WT));
170 break;
171 case _PAGE_CACHE_MODE_WB:
172 break;
173 }
174
175 /*
176 * Ok, go for it..
177 */
178 area = get_vm_area_caller(size, VM_IOREMAP, caller);
179 if (!area)
180 goto err_free_memtype;
181 area->phys_addr = phys_addr;
182 vaddr = (unsigned long) area->addr;
183
184 if (kernel_map_sync_memtype(phys_addr, size, pcm))
185 goto err_free_area;
186
187 if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot))
188 goto err_free_area;
189
190 ret_addr = (void __iomem *) (vaddr + offset);
191 mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);
192
193 /*
194 * Check if the request spans more than any BAR in the iomem resource
195 * tree.
196 */
197 if (iomem_map_sanity_check(unaligned_phys_addr, unaligned_size))
198 pr_warn("caller %pS mapping multiple BARs\n", caller);
199
200 return ret_addr;
201err_free_area:
202 free_vm_area(area);
203err_free_memtype:
204 free_memtype(phys_addr, phys_addr + size);
205 return NULL;
206}
207
208/**
209 * ioremap_nocache - map bus memory into CPU space
210 * @phys_addr: bus address of the memory
211 * @size: size of the resource to map
212 *
213 * ioremap_nocache performs a platform specific sequence of operations to
214 * make bus memory CPU accessible via the readb/readw/readl/writeb/
215 * writew/writel functions and the other mmio helpers. The returned
216 * address is not guaranteed to be usable directly as a virtual
217 * address.
218 *
219 * This version of ioremap ensures that the memory is marked uncachable
220 * on the CPU as well as honouring existing caching rules from things like
221 * the PCI bus. Note that there are other caches and buffers on many
222 * busses. In particular driver authors should read up on PCI writes
223 *
224 * It's useful if some control registers are in such an area and
225 * write combining or read caching is not desirable:
226 *
227 * Must be freed with iounmap.
228 */
229void __iomem *ioremap_nocache(resource_size_t phys_addr, unsigned long size)
230{
231 /*
232 * Ideally, this should be:
233 * pat_enabled() ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
234 *
235 * Till we fix all X drivers to use ioremap_wc(), we will use
236 * UC MINUS. Drivers that are certain they need or can already
237 * be converted over to strong UC can use ioremap_uc().
238 */
239 enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;
240
241 return __ioremap_caller(phys_addr, size, pcm,
242 __builtin_return_address(0));
243}
244EXPORT_SYMBOL(ioremap_nocache);
245
246/**
247 * ioremap_uc - map bus memory into CPU space as strongly uncachable
248 * @phys_addr: bus address of the memory
249 * @size: size of the resource to map
250 *
251 * ioremap_uc performs a platform specific sequence of operations to
252 * make bus memory CPU accessible via the readb/readw/readl/writeb/
253 * writew/writel functions and the other mmio helpers. The returned
254 * address is not guaranteed to be usable directly as a virtual
255 * address.
256 *
257 * This version of ioremap ensures that the memory is marked with a strong
258 * preference as completely uncachable on the CPU when possible. For non-PAT
259 * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT
260 * systems this will set the PAT entry for the pages as strong UC. This call
261 * will honor existing caching rules from things like the PCI bus. Note that
262 * there are other caches and buffers on many busses. In particular driver
263 * authors should read up on PCI writes.
264 *
265 * It's useful if some control registers are in such an area and
266 * write combining or read caching is not desirable:
267 *
268 * Must be freed with iounmap.
269 */
270void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
271{
272 enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;
273
274 return __ioremap_caller(phys_addr, size, pcm,
275 __builtin_return_address(0));
276}
277EXPORT_SYMBOL_GPL(ioremap_uc);
278
279/**
280 * ioremap_wc - map memory into CPU space write combined
281 * @phys_addr: bus address of the memory
282 * @size: size of the resource to map
283 *
284 * This version of ioremap ensures that the memory is marked write combining.
285 * Write combining allows faster writes to some hardware devices.
286 *
287 * Must be freed with iounmap.
288 */
289void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
290{
291 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
292 __builtin_return_address(0));
293}
294EXPORT_SYMBOL(ioremap_wc);
295
296/**
297 * ioremap_wt - map memory into CPU space write through
298 * @phys_addr: bus address of the memory
299 * @size: size of the resource to map
300 *
301 * This version of ioremap ensures that the memory is marked write through.
302 * Write through stores data into memory while keeping the cache up-to-date.
303 *
304 * Must be freed with iounmap.
305 */
306void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
307{
308 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
309 __builtin_return_address(0));
310}
311EXPORT_SYMBOL(ioremap_wt);
312
313void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
314{
315 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
316 __builtin_return_address(0));
317}
318EXPORT_SYMBOL(ioremap_cache);
319
320void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
321 unsigned long prot_val)
322{
323 return __ioremap_caller(phys_addr, size,
324 pgprot2cachemode(__pgprot(prot_val)),
325 __builtin_return_address(0));
326}
327EXPORT_SYMBOL(ioremap_prot);
328
329/**
330 * iounmap - Free a IO remapping
331 * @addr: virtual address from ioremap_*
332 *
333 * Caller must ensure there is only one unmapping for the same pointer.
334 */
335void iounmap(volatile void __iomem *addr)
336{
337 struct vm_struct *p, *o;
338
339 if ((void __force *)addr <= high_memory)
340 return;
341
342 /*
343 * __ioremap special-cases the PCI/ISA range by not instantiating a
344 * vm_area and by simply returning an address into the kernel mapping
345 * of ISA space. So handle that here.
346 */
347 if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) &&
348 (void __force *)addr < phys_to_virt(ISA_END_ADDRESS))
349 return;
350
351 addr = (volatile void __iomem *)
352 (PAGE_MASK & (unsigned long __force)addr);
353
354 mmiotrace_iounmap(addr);
355
356 /* Use the vm area unlocked, assuming the caller
357 ensures there isn't another iounmap for the same address
358 in parallel. Reuse of the virtual address is prevented by
359 leaving it in the global lists until we're done with it.
360 cpa takes care of the direct mappings. */
361 p = find_vm_area((void __force *)addr);
362
363 if (!p) {
364 printk(KERN_ERR "iounmap: bad address %p\n", addr);
365 dump_stack();
366 return;
367 }
368
369 free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p));
370
371 /* Finally remove it */
372 o = remove_vm_area((void __force *)addr);
373 BUG_ON(p != o || o == NULL);
374 kfree(p);
375}
376EXPORT_SYMBOL(iounmap);
377
378int __init arch_ioremap_pud_supported(void)
379{
380#ifdef CONFIG_X86_64
381 return cpu_has_gbpages;
382#else
383 return 0;
384#endif
385}
386
387int __init arch_ioremap_pmd_supported(void)
388{
389 return cpu_has_pse;
390}
391
392/*
393 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
394 * access
395 */
396void *xlate_dev_mem_ptr(phys_addr_t phys)
397{
398 unsigned long start = phys & PAGE_MASK;
399 unsigned long offset = phys & ~PAGE_MASK;
400 void *vaddr;
401
402 /* If page is RAM, we can use __va. Otherwise ioremap and unmap. */
403 if (page_is_ram(start >> PAGE_SHIFT))
404 return __va(phys);
405
406 vaddr = ioremap_cache(start, PAGE_SIZE);
407 /* Only add the offset on success and return NULL if the ioremap() failed: */
408 if (vaddr)
409 vaddr += offset;
410
411 return vaddr;
412}
413
414void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
415{
416 if (page_is_ram(phys >> PAGE_SHIFT))
417 return;
418
419 iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK));
420}
421
422static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;
423
424static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
425{
426 /* Don't assume we're using swapper_pg_dir at this point */
427 pgd_t *base = __va(read_cr3());
428 pgd_t *pgd = &base[pgd_index(addr)];
429 pud_t *pud = pud_offset(pgd, addr);
430 pmd_t *pmd = pmd_offset(pud, addr);
431
432 return pmd;
433}
434
435static inline pte_t * __init early_ioremap_pte(unsigned long addr)
436{
437 return &bm_pte[pte_index(addr)];
438}
439
440bool __init is_early_ioremap_ptep(pte_t *ptep)
441{
442 return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)];
443}
444
445void __init early_ioremap_init(void)
446{
447 pmd_t *pmd;
448
449#ifdef CONFIG_X86_64
450 BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
451#else
452 WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
453#endif
454
455 early_ioremap_setup();
456
457 pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
458 memset(bm_pte, 0, sizeof(bm_pte));
459 pmd_populate_kernel(&init_mm, pmd, bm_pte);
460
461 /*
462 * The boot-ioremap range spans multiple pmds, for which
463 * we are not prepared:
464 */
465#define __FIXADDR_TOP (-PAGE_SIZE)
466 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
467 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
468#undef __FIXADDR_TOP
469 if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
470 WARN_ON(1);
471 printk(KERN_WARNING "pmd %p != %p\n",
472 pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
473 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
474 fix_to_virt(FIX_BTMAP_BEGIN));
475 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END): %08lx\n",
476 fix_to_virt(FIX_BTMAP_END));
477
478 printk(KERN_WARNING "FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
479 printk(KERN_WARNING "FIX_BTMAP_BEGIN: %d\n",
480 FIX_BTMAP_BEGIN);
481 }
482}
483
484void __init __early_set_fixmap(enum fixed_addresses idx,
485 phys_addr_t phys, pgprot_t flags)
486{
487 unsigned long addr = __fix_to_virt(idx);
488 pte_t *pte;
489
490 if (idx >= __end_of_fixed_addresses) {
491 BUG();
492 return;
493 }
494 pte = early_ioremap_pte(addr);
495
496 if (pgprot_val(flags))
497 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
498 else
499 pte_clear(&init_mm, addr, pte);
500 __flush_tlb_one(addr);
501}