Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/mm/ioremap.c | |
3 | * | |
4 | * Re-map IO memory to kernel address space so that we can access it. | |
5 | * | |
6 | * (C) Copyright 1995 1996 Linus Torvalds | |
7 | * | |
8 | * Hacked for ARM by Phil Blundell <philb@gnu.org> | |
9 | * Hacked to allow all architectures to build, and various cleanups | |
10 | * by Russell King | |
11 | * | |
12 | * This allows a driver to remap an arbitrary region of bus memory into | |
13 | * virtual space. One should *only* use readl, writel, memcpy_toio and | |
14 | * so on with such remapped areas. | |
15 | * | |
16 | * Because the ARM only has a 32-bit address space we can't address the | |
17 | * whole of the (physical) PCI space at once. PCI huge-mode addressing | |
18 | * allows us to circumvent this restriction by splitting PCI space into | |
19 | * two 2GB chunks and mapping only one at a time into processor memory. | |
20 | * We use MMU protection domains to trap any attempt to access the bank | |
21 | * that is not currently mapped. (This isn't fully implemented yet.) | |
22 | */ | |
23 | #include <linux/module.h> | |
24 | #include <linux/errno.h> | |
25 | #include <linux/mm.h> | |
26 | #include <linux/vmalloc.h> | |
fced80c7 | 27 | #include <linux/io.h> |
1da177e4 | 28 | |
0ba8b9b2 | 29 | #include <asm/cputype.h> |
1da177e4 | 30 | #include <asm/cacheflush.h> |
ff0daca5 RK |
31 | #include <asm/mmu_context.h> |
32 | #include <asm/pgalloc.h> | |
1da177e4 | 33 | #include <asm/tlbflush.h> |
ff0daca5 RK |
34 | #include <asm/sizes.h> |
35 | ||
b29e9f5e RK |
36 | #include <asm/mach/map.h> |
37 | #include "mm.h" | |
38 | ||
69d3a84a HD |
39 | int ioremap_page(unsigned long virt, unsigned long phys, |
40 | const struct mem_type *mtype) | |
41 | { | |
d7461963 RK |
42 | return ioremap_page_range(virt, virt + PAGE_SIZE, phys, |
43 | __pgprot(mtype->prot_pte)); | |
69d3a84a HD |
44 | } |
45 | EXPORT_SYMBOL(ioremap_page); | |
ff0daca5 RK |
46 | |
47 | void __check_kvm_seq(struct mm_struct *mm) | |
48 | { | |
49 | unsigned int seq; | |
50 | ||
51 | do { | |
52 | seq = init_mm.context.kvm_seq; | |
53 | memcpy(pgd_offset(mm, VMALLOC_START), | |
54 | pgd_offset_k(VMALLOC_START), | |
55 | sizeof(pgd_t) * (pgd_index(VMALLOC_END) - | |
56 | pgd_index(VMALLOC_START))); | |
57 | mm->context.kvm_seq = seq; | |
58 | } while (seq != init_mm.context.kvm_seq); | |
59 | } | |
60 | ||
da028779 | 61 | #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) |
ff0daca5 RK |
62 | /* |
63 | * Section support is unsafe on SMP - If you iounmap and ioremap a region, | |
64 | * the other CPUs will not see this change until their next context switch. | |
65 | * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs | |
66 | * which requires the new ioremap'd region to be referenced, the CPU will | |
67 | * reference the _old_ region. | |
68 | * | |
31aa8fd6 RK |
69 | * Note that get_vm_area_caller() allocates a guard 4K page, so we need to |
70 | * mask the size back to 1MB aligned or we will overflow in the loop below. | |
ff0daca5 RK |
71 | */ |
72 | static void unmap_area_sections(unsigned long virt, unsigned long size) | |
73 | { | |
24f11ec0 | 74 | unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1)); |
ff0daca5 | 75 | pgd_t *pgd; |
03a6b827 CM |
76 | pud_t *pud; |
77 | pmd_t *pmdp; | |
ff0daca5 RK |
78 | |
79 | flush_cache_vunmap(addr, end); | |
80 | pgd = pgd_offset_k(addr); | |
03a6b827 CM |
81 | pud = pud_offset(pgd, addr); |
82 | pmdp = pmd_offset(pud, addr); | |
ff0daca5 | 83 | do { |
03a6b827 | 84 | pmd_t pmd = *pmdp; |
ff0daca5 | 85 | |
ff0daca5 RK |
86 | if (!pmd_none(pmd)) { |
87 | /* | |
88 | * Clear the PMD from the page table, and | |
89 | * increment the kvm sequence so others | |
90 | * notice this change. | |
91 | * | |
92 | * Note: this is still racy on SMP machines. | |
93 | */ | |
94 | pmd_clear(pmdp); | |
95 | init_mm.context.kvm_seq++; | |
96 | ||
97 | /* | |
98 | * Free the page table, if there was one. | |
99 | */ | |
100 | if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE) | |
5e541973 | 101 | pte_free_kernel(&init_mm, pmd_page_vaddr(pmd)); |
ff0daca5 RK |
102 | } |
103 | ||
03a6b827 CM |
104 | addr += PMD_SIZE; |
105 | pmdp += 2; | |
ff0daca5 RK |
106 | } while (addr < end); |
107 | ||
108 | /* | |
109 | * Ensure that the active_mm is up to date - we want to | |
110 | * catch any use-after-iounmap cases. | |
111 | */ | |
112 | if (current->active_mm->context.kvm_seq != init_mm.context.kvm_seq) | |
113 | __check_kvm_seq(current->active_mm); | |
114 | ||
115 | flush_tlb_kernel_range(virt, end); | |
116 | } | |
117 | ||
118 | static int | |
119 | remap_area_sections(unsigned long virt, unsigned long pfn, | |
b29e9f5e | 120 | size_t size, const struct mem_type *type) |
ff0daca5 | 121 | { |
b29e9f5e | 122 | unsigned long addr = virt, end = virt + size; |
ff0daca5 | 123 | pgd_t *pgd; |
03a6b827 CM |
124 | pud_t *pud; |
125 | pmd_t *pmd; | |
ff0daca5 RK |
126 | |
127 | /* | |
128 | * Remove and free any PTE-based mapping, and | |
129 | * sync the current kernel mapping. | |
130 | */ | |
131 | unmap_area_sections(virt, size); | |
132 | ||
ff0daca5 | 133 | pgd = pgd_offset_k(addr); |
03a6b827 CM |
134 | pud = pud_offset(pgd, addr); |
135 | pmd = pmd_offset(pud, addr); | |
ff0daca5 | 136 | do { |
b29e9f5e | 137 | pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect); |
ff0daca5 | 138 | pfn += SZ_1M >> PAGE_SHIFT; |
b29e9f5e | 139 | pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect); |
ff0daca5 RK |
140 | pfn += SZ_1M >> PAGE_SHIFT; |
141 | flush_pmd_entry(pmd); | |
142 | ||
03a6b827 CM |
143 | addr += PMD_SIZE; |
144 | pmd += 2; | |
ff0daca5 RK |
145 | } while (addr < end); |
146 | ||
147 | return 0; | |
148 | } | |
a069c896 LB |
149 | |
150 | static int | |
151 | remap_area_supersections(unsigned long virt, unsigned long pfn, | |
b29e9f5e | 152 | size_t size, const struct mem_type *type) |
a069c896 | 153 | { |
b29e9f5e | 154 | unsigned long addr = virt, end = virt + size; |
a069c896 | 155 | pgd_t *pgd; |
03a6b827 CM |
156 | pud_t *pud; |
157 | pmd_t *pmd; | |
a069c896 LB |
158 | |
159 | /* | |
160 | * Remove and free any PTE-based mapping, and | |
161 | * sync the current kernel mapping. | |
162 | */ | |
163 | unmap_area_sections(virt, size); | |
164 | ||
a069c896 | 165 | pgd = pgd_offset_k(virt); |
03a6b827 CM |
166 | pud = pud_offset(pgd, addr); |
167 | pmd = pmd_offset(pud, addr); | |
a069c896 LB |
168 | do { |
169 | unsigned long super_pmd_val, i; | |
170 | ||
b29e9f5e RK |
171 | super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect | |
172 | PMD_SECT_SUPER; | |
a069c896 LB |
173 | super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20; |
174 | ||
175 | for (i = 0; i < 8; i++) { | |
a069c896 LB |
176 | pmd[0] = __pmd(super_pmd_val); |
177 | pmd[1] = __pmd(super_pmd_val); | |
178 | flush_pmd_entry(pmd); | |
179 | ||
03a6b827 CM |
180 | addr += PMD_SIZE; |
181 | pmd += 2; | |
a069c896 LB |
182 | } |
183 | ||
184 | pfn += SUPERSECTION_SIZE >> PAGE_SHIFT; | |
185 | } while (addr < end); | |
186 | ||
187 | return 0; | |
188 | } | |
ff0daca5 RK |
189 | #endif |
190 | ||
31aa8fd6 RK |
191 | void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn, |
192 | unsigned long offset, size_t size, unsigned int mtype, void *caller) | |
9d4ae727 | 193 | { |
b29e9f5e | 194 | const struct mem_type *type; |
ff0daca5 | 195 | int err; |
9d4ae727 DS |
196 | unsigned long addr; |
197 | struct vm_struct * area; | |
a069c896 | 198 | |
da028779 | 199 | #ifndef CONFIG_ARM_LPAE |
a069c896 LB |
200 | /* |
201 | * High mappings must be supersection aligned | |
202 | */ | |
203 | if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK)) | |
204 | return NULL; | |
da028779 | 205 | #endif |
9d4ae727 | 206 | |
3603ab2b RK |
207 | type = get_mem_type(mtype); |
208 | if (!type) | |
209 | return NULL; | |
b29e9f5e | 210 | |
6d78b5f9 RK |
211 | /* |
212 | * Page align the mapping size, taking account of any offset. | |
213 | */ | |
214 | size = PAGE_ALIGN(offset + size); | |
c924aff8 | 215 | |
576d2f25 NP |
216 | /* |
217 | * Try to reuse one of the static mapping whenever possible. | |
218 | */ | |
219 | read_lock(&vmlist_lock); | |
220 | for (area = vmlist; area; area = area->next) { | |
221 | if (!size || (sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) | |
222 | break; | |
223 | if (!(area->flags & VM_ARM_STATIC_MAPPING)) | |
224 | continue; | |
225 | if ((area->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype)) | |
226 | continue; | |
227 | if (__phys_to_pfn(area->phys_addr) > pfn || | |
97f10409 | 228 | __pfn_to_phys(pfn) + size-1 > area->phys_addr + area->size-1) |
576d2f25 NP |
229 | continue; |
230 | /* we can drop the lock here as we know *area is static */ | |
231 | read_unlock(&vmlist_lock); | |
232 | addr = (unsigned long)area->addr; | |
233 | addr += __pfn_to_phys(pfn) - area->phys_addr; | |
234 | return (void __iomem *) (offset + addr); | |
235 | } | |
236 | read_unlock(&vmlist_lock); | |
237 | ||
238 | /* | |
239 | * Don't allow RAM to be mapped - this causes problems with ARMv6+ | |
240 | */ | |
241 | if (WARN_ON(pfn_valid(pfn))) | |
242 | return NULL; | |
243 | ||
31aa8fd6 | 244 | area = get_vm_area_caller(size, VM_IOREMAP, caller); |
9d4ae727 DS |
245 | if (!area) |
246 | return NULL; | |
247 | addr = (unsigned long)area->addr; | |
ff0daca5 | 248 | |
da028779 | 249 | #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) |
412489af CM |
250 | if (DOMAIN_IO == 0 && |
251 | (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) || | |
4a56c1e4 | 252 | cpu_is_xsc3()) && pfn >= 0x100000 && |
a069c896 LB |
253 | !((__pfn_to_phys(pfn) | size | addr) & ~SUPERSECTION_MASK)) { |
254 | area->flags |= VM_ARM_SECTION_MAPPING; | |
b29e9f5e | 255 | err = remap_area_supersections(addr, pfn, size, type); |
a069c896 | 256 | } else if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) { |
ff0daca5 | 257 | area->flags |= VM_ARM_SECTION_MAPPING; |
b29e9f5e | 258 | err = remap_area_sections(addr, pfn, size, type); |
ff0daca5 RK |
259 | } else |
260 | #endif | |
d7461963 RK |
261 | err = ioremap_page_range(addr, addr + size, __pfn_to_phys(pfn), |
262 | __pgprot(type->prot_pte)); | |
ff0daca5 RK |
263 | |
264 | if (err) { | |
478922c2 | 265 | vunmap((void *)addr); |
9d4ae727 DS |
266 | return NULL; |
267 | } | |
ff0daca5 RK |
268 | |
269 | flush_cache_vmap(addr, addr + size); | |
270 | return (void __iomem *) (offset + addr); | |
9d4ae727 | 271 | } |
9d4ae727 | 272 | |
31aa8fd6 RK |
273 | void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size, |
274 | unsigned int mtype, void *caller) | |
1da177e4 | 275 | { |
9d4ae727 DS |
276 | unsigned long last_addr; |
277 | unsigned long offset = phys_addr & ~PAGE_MASK; | |
278 | unsigned long pfn = __phys_to_pfn(phys_addr); | |
1da177e4 | 279 | |
9d4ae727 DS |
280 | /* |
281 | * Don't allow wraparound or zero size | |
282 | */ | |
1da177e4 LT |
283 | last_addr = phys_addr + size - 1; |
284 | if (!size || last_addr < phys_addr) | |
285 | return NULL; | |
286 | ||
31aa8fd6 RK |
287 | return __arm_ioremap_pfn_caller(pfn, offset, size, mtype, |
288 | caller); | |
289 | } | |
290 | ||
291 | /* | |
292 | * Remap an arbitrary physical address space into the kernel virtual | |
293 | * address space. Needed when the kernel wants to access high addresses | |
294 | * directly. | |
295 | * | |
296 | * NOTE! We need to allow non-page-aligned mappings too: we will obviously | |
297 | * have to convert them into an offset in a page-aligned mapping, but the | |
298 | * caller shouldn't need to know that small detail. | |
299 | */ | |
300 | void __iomem * | |
301 | __arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size, | |
302 | unsigned int mtype) | |
303 | { | |
304 | return __arm_ioremap_pfn_caller(pfn, offset, size, mtype, | |
305 | __builtin_return_address(0)); | |
306 | } | |
307 | EXPORT_SYMBOL(__arm_ioremap_pfn); | |
308 | ||
4fe7ef3a RH |
309 | void __iomem * (*arch_ioremap_caller)(unsigned long, size_t, |
310 | unsigned int, void *) = | |
311 | __arm_ioremap_caller; | |
312 | ||
31aa8fd6 RK |
313 | void __iomem * |
314 | __arm_ioremap(unsigned long phys_addr, size_t size, unsigned int mtype) | |
315 | { | |
4fe7ef3a RH |
316 | return arch_ioremap_caller(phys_addr, size, mtype, |
317 | __builtin_return_address(0)); | |
1da177e4 | 318 | } |
3603ab2b | 319 | EXPORT_SYMBOL(__arm_ioremap); |
1da177e4 | 320 | |
6c5482d5 TL |
321 | /* |
322 | * Remap an arbitrary physical address space into the kernel virtual | |
323 | * address space as memory. Needed when the kernel wants to execute | |
324 | * code in external memory. This is needed for reprogramming source | |
325 | * clocks that would affect normal memory for example. Please see | |
326 | * CONFIG_GENERIC_ALLOCATOR for allocating external memory. | |
327 | */ | |
328 | void __iomem * | |
329 | __arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached) | |
330 | { | |
331 | unsigned int mtype; | |
332 | ||
333 | if (cached) | |
334 | mtype = MT_MEMORY; | |
335 | else | |
336 | mtype = MT_MEMORY_NONCACHED; | |
337 | ||
338 | return __arm_ioremap_caller(phys_addr, size, mtype, | |
339 | __builtin_return_address(0)); | |
340 | } | |
341 | ||
09d9bae0 | 342 | void __iounmap(volatile void __iomem *io_addr) |
1da177e4 | 343 | { |
09d9bae0 | 344 | void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr); |
6ee723a6 | 345 | struct vm_struct *vm; |
ff0daca5 | 346 | |
6ee723a6 NP |
347 | read_lock(&vmlist_lock); |
348 | for (vm = vmlist; vm; vm = vm->next) { | |
576d2f25 | 349 | if (vm->addr > addr) |
ff0daca5 | 350 | break; |
576d2f25 NP |
351 | if (!(vm->flags & VM_IOREMAP)) |
352 | continue; | |
353 | /* If this is a static mapping we must leave it alone */ | |
354 | if ((vm->flags & VM_ARM_STATIC_MAPPING) && | |
355 | (vm->addr <= addr) && (vm->addr + vm->size > addr)) { | |
356 | read_unlock(&vmlist_lock); | |
357 | return; | |
ff0daca5 | 358 | } |
6ae25a5b | 359 | #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE) |
576d2f25 NP |
360 | /* |
361 | * If this is a section based mapping we need to handle it | |
362 | * specially as the VM subsystem does not know how to handle | |
363 | * such a beast. | |
364 | */ | |
365 | if ((vm->addr == addr) && | |
366 | (vm->flags & VM_ARM_SECTION_MAPPING)) { | |
367 | unmap_area_sections((unsigned long)vm->addr, vm->size); | |
368 | break; | |
369 | } | |
370 | #endif | |
ff0daca5 | 371 | } |
6ee723a6 | 372 | read_unlock(&vmlist_lock); |
ff0daca5 | 373 | |
24f11ec0 | 374 | vunmap(addr); |
1da177e4 | 375 | } |
4fe7ef3a RH |
376 | |
377 | void (*arch_iounmap)(volatile void __iomem *) = __iounmap; | |
378 | ||
379 | void __arm_iounmap(volatile void __iomem *io_addr) | |
380 | { | |
381 | arch_iounmap(io_addr); | |
382 | } | |
383 | EXPORT_SYMBOL(__arm_iounmap); |