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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/mm/ioremap.c
4 *
5 * Re-map IO memory to kernel address space so that we can access it.
6 *
7 * (C) Copyright 1995 1996 Linus Torvalds
8 *
9 * Hacked for ARM by Phil Blundell <philb@gnu.org>
10 * Hacked to allow all architectures to build, and various cleanups
11 * by Russell King
12 *
13 * This allows a driver to remap an arbitrary region of bus memory into
14 * virtual space. One should *only* use readl, writel, memcpy_toio and
15 * so on with such remapped areas.
16 *
17 * Because the ARM only has a 32-bit address space we can't address the
18 * whole of the (physical) PCI space at once. PCI huge-mode addressing
19 * allows us to circumvent this restriction by splitting PCI space into
20 * two 2GB chunks and mapping only one at a time into processor memory.
21 * We use MMU protection domains to trap any attempt to access the bank
22 * that is not currently mapped. (This isn't fully implemented yet.)
23 */
24#include <linux/module.h>
25#include <linux/errno.h>
26#include <linux/kasan.h>
27#include <linux/mm.h>
28#include <linux/vmalloc.h>
29#include <linux/io.h>
30#include <linux/sizes.h>
31#include <linux/memblock.h>
32
33#include <asm/cp15.h>
34#include <asm/cputype.h>
35#include <asm/cacheflush.h>
36#include <asm/early_ioremap.h>
37#include <asm/mmu_context.h>
38#include <asm/pgalloc.h>
39#include <asm/tlbflush.h>
40#include <asm/set_memory.h>
41#include <asm/system_info.h>
42
43#include <asm/mach/map.h>
44#include <asm/mach/pci.h>
45#include "mm.h"
46
47
48LIST_HEAD(static_vmlist);
49
50static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
51 size_t size, unsigned int mtype)
52{
53 struct static_vm *svm;
54 struct vm_struct *vm;
55
56 list_for_each_entry(svm, &static_vmlist, list) {
57 vm = &svm->vm;
58 if (!(vm->flags & VM_ARM_STATIC_MAPPING))
59 continue;
60 if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
61 continue;
62
63 if (vm->phys_addr > paddr ||
64 paddr + size - 1 > vm->phys_addr + vm->size - 1)
65 continue;
66
67 return svm;
68 }
69
70 return NULL;
71}
72
73struct static_vm *find_static_vm_vaddr(void *vaddr)
74{
75 struct static_vm *svm;
76 struct vm_struct *vm;
77
78 list_for_each_entry(svm, &static_vmlist, list) {
79 vm = &svm->vm;
80
81 /* static_vmlist is ascending order */
82 if (vm->addr > vaddr)
83 break;
84
85 if (vm->addr <= vaddr && vm->addr + vm->size > vaddr)
86 return svm;
87 }
88
89 return NULL;
90}
91
92void __init add_static_vm_early(struct static_vm *svm)
93{
94 struct static_vm *curr_svm;
95 struct vm_struct *vm;
96 void *vaddr;
97
98 vm = &svm->vm;
99 vm_area_add_early(vm);
100 vaddr = vm->addr;
101
102 list_for_each_entry(curr_svm, &static_vmlist, list) {
103 vm = &curr_svm->vm;
104
105 if (vm->addr > vaddr)
106 break;
107 }
108 list_add_tail(&svm->list, &curr_svm->list);
109}
110
111int ioremap_page(unsigned long virt, unsigned long phys,
112 const struct mem_type *mtype)
113{
114 return vmap_page_range(virt, virt + PAGE_SIZE, phys,
115 __pgprot(mtype->prot_pte));
116}
117EXPORT_SYMBOL(ioremap_page);
118
119#ifdef CONFIG_KASAN
120static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)
121{
122 return (unsigned long)kasan_mem_to_shadow((void *)addr);
123}
124#else
125static unsigned long arm_kasan_mem_to_shadow(unsigned long addr)
126{
127 return 0;
128}
129#endif
130
131static void memcpy_pgd(struct mm_struct *mm, unsigned long start,
132 unsigned long end)
133{
134 end = ALIGN(end, PGDIR_SIZE);
135 memcpy(pgd_offset(mm, start), pgd_offset_k(start),
136 sizeof(pgd_t) * (pgd_index(end) - pgd_index(start)));
137}
138
139void __check_vmalloc_seq(struct mm_struct *mm)
140{
141 int seq;
142
143 do {
144 seq = atomic_read_acquire(&init_mm.context.vmalloc_seq);
145 memcpy_pgd(mm, VMALLOC_START, VMALLOC_END);
146 if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
147 unsigned long start =
148 arm_kasan_mem_to_shadow(VMALLOC_START);
149 unsigned long end =
150 arm_kasan_mem_to_shadow(VMALLOC_END);
151 memcpy_pgd(mm, start, end);
152 }
153 /*
154 * Use a store-release so that other CPUs that observe the
155 * counter's new value are guaranteed to see the results of the
156 * memcpy as well.
157 */
158 atomic_set_release(&mm->context.vmalloc_seq, seq);
159 } while (seq != atomic_read(&init_mm.context.vmalloc_seq));
160}
161
162#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
163/*
164 * Section support is unsafe on SMP - If you iounmap and ioremap a region,
165 * the other CPUs will not see this change until their next context switch.
166 * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
167 * which requires the new ioremap'd region to be referenced, the CPU will
168 * reference the _old_ region.
169 *
170 * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
171 * mask the size back to 1MB aligned or we will overflow in the loop below.
172 */
173static void unmap_area_sections(unsigned long virt, unsigned long size)
174{
175 unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
176 pmd_t *pmdp = pmd_off_k(addr);
177
178 do {
179 pmd_t pmd = *pmdp;
180
181 if (!pmd_none(pmd)) {
182 /*
183 * Clear the PMD from the page table, and
184 * increment the vmalloc sequence so others
185 * notice this change.
186 *
187 * Note: this is still racy on SMP machines.
188 */
189 pmd_clear(pmdp);
190 atomic_inc_return_release(&init_mm.context.vmalloc_seq);
191
192 /*
193 * Free the page table, if there was one.
194 */
195 if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
196 pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
197 }
198
199 addr += PMD_SIZE;
200 pmdp += 2;
201 } while (addr < end);
202
203 /*
204 * Ensure that the active_mm is up to date - we want to
205 * catch any use-after-iounmap cases.
206 */
207 check_vmalloc_seq(current->active_mm);
208
209 flush_tlb_kernel_range(virt, end);
210}
211
212static int
213remap_area_sections(unsigned long virt, unsigned long pfn,
214 size_t size, const struct mem_type *type)
215{
216 unsigned long addr = virt, end = virt + size;
217 pmd_t *pmd = pmd_off_k(addr);
218
219 /*
220 * Remove and free any PTE-based mapping, and
221 * sync the current kernel mapping.
222 */
223 unmap_area_sections(virt, size);
224
225 do {
226 pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
227 pfn += SZ_1M >> PAGE_SHIFT;
228 pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
229 pfn += SZ_1M >> PAGE_SHIFT;
230 flush_pmd_entry(pmd);
231
232 addr += PMD_SIZE;
233 pmd += 2;
234 } while (addr < end);
235
236 return 0;
237}
238
239static int
240remap_area_supersections(unsigned long virt, unsigned long pfn,
241 size_t size, const struct mem_type *type)
242{
243 unsigned long addr = virt, end = virt + size;
244 pmd_t *pmd = pmd_off_k(addr);
245
246 /*
247 * Remove and free any PTE-based mapping, and
248 * sync the current kernel mapping.
249 */
250 unmap_area_sections(virt, size);
251 do {
252 unsigned long super_pmd_val, i;
253
254 super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
255 PMD_SECT_SUPER;
256 super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
257
258 for (i = 0; i < 8; i++) {
259 pmd[0] = __pmd(super_pmd_val);
260 pmd[1] = __pmd(super_pmd_val);
261 flush_pmd_entry(pmd);
262
263 addr += PMD_SIZE;
264 pmd += 2;
265 }
266
267 pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
268 } while (addr < end);
269
270 return 0;
271}
272#endif
273
274static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
275 unsigned long offset, size_t size, unsigned int mtype, void *caller)
276{
277 const struct mem_type *type;
278 int err;
279 unsigned long addr;
280 struct vm_struct *area;
281 phys_addr_t paddr = __pfn_to_phys(pfn);
282
283#ifndef CONFIG_ARM_LPAE
284 /*
285 * High mappings must be supersection aligned
286 */
287 if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
288 return NULL;
289#endif
290
291 type = get_mem_type(mtype);
292 if (!type)
293 return NULL;
294
295 /*
296 * Page align the mapping size, taking account of any offset.
297 */
298 size = PAGE_ALIGN(offset + size);
299
300 /*
301 * Try to reuse one of the static mapping whenever possible.
302 */
303 if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
304 struct static_vm *svm;
305
306 svm = find_static_vm_paddr(paddr, size, mtype);
307 if (svm) {
308 addr = (unsigned long)svm->vm.addr;
309 addr += paddr - svm->vm.phys_addr;
310 return (void __iomem *) (offset + addr);
311 }
312 }
313
314 /*
315 * Don't allow RAM to be mapped with mismatched attributes - this
316 * causes problems with ARMv6+
317 */
318 if (WARN_ON(memblock_is_map_memory(PFN_PHYS(pfn)) &&
319 mtype != MT_MEMORY_RW))
320 return NULL;
321
322 area = get_vm_area_caller(size, VM_IOREMAP, caller);
323 if (!area)
324 return NULL;
325 addr = (unsigned long)area->addr;
326 area->phys_addr = paddr;
327
328#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
329 if (DOMAIN_IO == 0 &&
330 (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
331 cpu_is_xsc3()) && pfn >= 0x100000 &&
332 !((paddr | size | addr) & ~SUPERSECTION_MASK)) {
333 area->flags |= VM_ARM_SECTION_MAPPING;
334 err = remap_area_supersections(addr, pfn, size, type);
335 } else if (!((paddr | size | addr) & ~PMD_MASK)) {
336 area->flags |= VM_ARM_SECTION_MAPPING;
337 err = remap_area_sections(addr, pfn, size, type);
338 } else
339#endif
340 err = ioremap_page_range(addr, addr + size, paddr,
341 __pgprot(type->prot_pte));
342
343 if (err) {
344 vunmap((void *)addr);
345 return NULL;
346 }
347
348 flush_cache_vmap(addr, addr + size);
349 return (void __iomem *) (offset + addr);
350}
351
352void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
353 unsigned int mtype, void *caller)
354{
355 phys_addr_t last_addr;
356 unsigned long offset = phys_addr & ~PAGE_MASK;
357 unsigned long pfn = __phys_to_pfn(phys_addr);
358
359 /*
360 * Don't allow wraparound or zero size
361 */
362 last_addr = phys_addr + size - 1;
363 if (!size || last_addr < phys_addr)
364 return NULL;
365
366 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
367 caller);
368}
369
370/*
371 * Remap an arbitrary physical address space into the kernel virtual
372 * address space. Needed when the kernel wants to access high addresses
373 * directly.
374 *
375 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
376 * have to convert them into an offset in a page-aligned mapping, but the
377 * caller shouldn't need to know that small detail.
378 */
379void __iomem *
380__arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
381 unsigned int mtype)
382{
383 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
384 __builtin_return_address(0));
385}
386EXPORT_SYMBOL(__arm_ioremap_pfn);
387
388void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
389 unsigned int, void *) =
390 __arm_ioremap_caller;
391
392void __iomem *ioremap(resource_size_t res_cookie, size_t size)
393{
394 return arch_ioremap_caller(res_cookie, size, MT_DEVICE,
395 __builtin_return_address(0));
396}
397EXPORT_SYMBOL(ioremap);
398
399void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
400{
401 return arch_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
402 __builtin_return_address(0));
403}
404EXPORT_SYMBOL(ioremap_cache);
405
406void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
407{
408 return arch_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
409 __builtin_return_address(0));
410}
411EXPORT_SYMBOL(ioremap_wc);
412
413/*
414 * Remap an arbitrary physical address space into the kernel virtual
415 * address space as memory. Needed when the kernel wants to execute
416 * code in external memory. This is needed for reprogramming source
417 * clocks that would affect normal memory for example. Please see
418 * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
419 */
420void __iomem *
421__arm_ioremap_exec(phys_addr_t phys_addr, size_t size, bool cached)
422{
423 unsigned int mtype;
424
425 if (cached)
426 mtype = MT_MEMORY_RWX;
427 else
428 mtype = MT_MEMORY_RWX_NONCACHED;
429
430 return __arm_ioremap_caller(phys_addr, size, mtype,
431 __builtin_return_address(0));
432}
433
434void __arm_iomem_set_ro(void __iomem *ptr, size_t size)
435{
436 set_memory_ro((unsigned long)ptr, PAGE_ALIGN(size) / PAGE_SIZE);
437}
438
439void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
440{
441 return (__force void *)arch_ioremap_caller(phys_addr, size,
442 MT_MEMORY_RW,
443 __builtin_return_address(0));
444}
445
446void iounmap(volatile void __iomem *io_addr)
447{
448 void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
449 struct static_vm *svm;
450
451 /* If this is a static mapping, we must leave it alone */
452 svm = find_static_vm_vaddr(addr);
453 if (svm)
454 return;
455
456#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
457 {
458 struct vm_struct *vm;
459
460 vm = find_vm_area(addr);
461
462 /*
463 * If this is a section based mapping we need to handle it
464 * specially as the VM subsystem does not know how to handle
465 * such a beast.
466 */
467 if (vm && (vm->flags & VM_ARM_SECTION_MAPPING))
468 unmap_area_sections((unsigned long)vm->addr, vm->size);
469 }
470#endif
471
472 vunmap(addr);
473}
474EXPORT_SYMBOL(iounmap);
475
476#if defined(CONFIG_PCI) || IS_ENABLED(CONFIG_PCMCIA)
477static int pci_ioremap_mem_type = MT_DEVICE;
478
479void pci_ioremap_set_mem_type(int mem_type)
480{
481 pci_ioremap_mem_type = mem_type;
482}
483
484int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
485{
486 unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start;
487
488 if (!(res->flags & IORESOURCE_IO))
489 return -EINVAL;
490
491 if (res->end > IO_SPACE_LIMIT)
492 return -EINVAL;
493
494 return vmap_page_range(vaddr, vaddr + resource_size(res), phys_addr,
495 __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte));
496}
497EXPORT_SYMBOL(pci_remap_iospace);
498
499void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
500{
501 return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
502 __builtin_return_address(0));
503}
504EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
505#endif
506
507/*
508 * Must be called after early_fixmap_init
509 */
510void __init early_ioremap_init(void)
511{
512 early_ioremap_setup();
513}
514
515bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size,
516 unsigned long flags)
517{
518 unsigned long pfn = PHYS_PFN(offset);
519
520 return memblock_is_map_memory(pfn);
521}
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>
27#include <linux/io.h>
28
29#include <asm/cp15.h>
30#include <asm/cputype.h>
31#include <asm/cacheflush.h>
32#include <asm/mmu_context.h>
33#include <asm/pgalloc.h>
34#include <asm/tlbflush.h>
35#include <asm/sizes.h>
36#include <asm/system_info.h>
37
38#include <asm/mach/map.h>
39#include "mm.h"
40
41int ioremap_page(unsigned long virt, unsigned long phys,
42 const struct mem_type *mtype)
43{
44 return ioremap_page_range(virt, virt + PAGE_SIZE, phys,
45 __pgprot(mtype->prot_pte));
46}
47EXPORT_SYMBOL(ioremap_page);
48
49void __check_kvm_seq(struct mm_struct *mm)
50{
51 unsigned int seq;
52
53 do {
54 seq = init_mm.context.kvm_seq;
55 memcpy(pgd_offset(mm, VMALLOC_START),
56 pgd_offset_k(VMALLOC_START),
57 sizeof(pgd_t) * (pgd_index(VMALLOC_END) -
58 pgd_index(VMALLOC_START)));
59 mm->context.kvm_seq = seq;
60 } while (seq != init_mm.context.kvm_seq);
61}
62
63#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
64/*
65 * Section support is unsafe on SMP - If you iounmap and ioremap a region,
66 * the other CPUs will not see this change until their next context switch.
67 * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
68 * which requires the new ioremap'd region to be referenced, the CPU will
69 * reference the _old_ region.
70 *
71 * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
72 * mask the size back to 1MB aligned or we will overflow in the loop below.
73 */
74static void unmap_area_sections(unsigned long virt, unsigned long size)
75{
76 unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
77 pgd_t *pgd;
78 pud_t *pud;
79 pmd_t *pmdp;
80
81 flush_cache_vunmap(addr, end);
82 pgd = pgd_offset_k(addr);
83 pud = pud_offset(pgd, addr);
84 pmdp = pmd_offset(pud, addr);
85 do {
86 pmd_t pmd = *pmdp;
87
88 if (!pmd_none(pmd)) {
89 /*
90 * Clear the PMD from the page table, and
91 * increment the kvm sequence so others
92 * notice this change.
93 *
94 * Note: this is still racy on SMP machines.
95 */
96 pmd_clear(pmdp);
97 init_mm.context.kvm_seq++;
98
99 /*
100 * Free the page table, if there was one.
101 */
102 if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
103 pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
104 }
105
106 addr += PMD_SIZE;
107 pmdp += 2;
108 } while (addr < end);
109
110 /*
111 * Ensure that the active_mm is up to date - we want to
112 * catch any use-after-iounmap cases.
113 */
114 if (current->active_mm->context.kvm_seq != init_mm.context.kvm_seq)
115 __check_kvm_seq(current->active_mm);
116
117 flush_tlb_kernel_range(virt, end);
118}
119
120static int
121remap_area_sections(unsigned long virt, unsigned long pfn,
122 size_t size, const struct mem_type *type)
123{
124 unsigned long addr = virt, end = virt + size;
125 pgd_t *pgd;
126 pud_t *pud;
127 pmd_t *pmd;
128
129 /*
130 * Remove and free any PTE-based mapping, and
131 * sync the current kernel mapping.
132 */
133 unmap_area_sections(virt, size);
134
135 pgd = pgd_offset_k(addr);
136 pud = pud_offset(pgd, addr);
137 pmd = pmd_offset(pud, addr);
138 do {
139 pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
140 pfn += SZ_1M >> PAGE_SHIFT;
141 pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
142 pfn += SZ_1M >> PAGE_SHIFT;
143 flush_pmd_entry(pmd);
144
145 addr += PMD_SIZE;
146 pmd += 2;
147 } while (addr < end);
148
149 return 0;
150}
151
152static int
153remap_area_supersections(unsigned long virt, unsigned long pfn,
154 size_t size, const struct mem_type *type)
155{
156 unsigned long addr = virt, end = virt + size;
157 pgd_t *pgd;
158 pud_t *pud;
159 pmd_t *pmd;
160
161 /*
162 * Remove and free any PTE-based mapping, and
163 * sync the current kernel mapping.
164 */
165 unmap_area_sections(virt, size);
166
167 pgd = pgd_offset_k(virt);
168 pud = pud_offset(pgd, addr);
169 pmd = pmd_offset(pud, addr);
170 do {
171 unsigned long super_pmd_val, i;
172
173 super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
174 PMD_SECT_SUPER;
175 super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
176
177 for (i = 0; i < 8; i++) {
178 pmd[0] = __pmd(super_pmd_val);
179 pmd[1] = __pmd(super_pmd_val);
180 flush_pmd_entry(pmd);
181
182 addr += PMD_SIZE;
183 pmd += 2;
184 }
185
186 pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
187 } while (addr < end);
188
189 return 0;
190}
191#endif
192
193void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
194 unsigned long offset, size_t size, unsigned int mtype, void *caller)
195{
196 const struct mem_type *type;
197 int err;
198 unsigned long addr;
199 struct vm_struct * area;
200
201#ifndef CONFIG_ARM_LPAE
202 /*
203 * High mappings must be supersection aligned
204 */
205 if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK))
206 return NULL;
207#endif
208
209 type = get_mem_type(mtype);
210 if (!type)
211 return NULL;
212
213 /*
214 * Page align the mapping size, taking account of any offset.
215 */
216 size = PAGE_ALIGN(offset + size);
217
218 /*
219 * Try to reuse one of the static mapping whenever possible.
220 */
221 read_lock(&vmlist_lock);
222 for (area = vmlist; area; area = area->next) {
223 if (!size || (sizeof(phys_addr_t) == 4 && pfn >= 0x100000))
224 break;
225 if (!(area->flags & VM_ARM_STATIC_MAPPING))
226 continue;
227 if ((area->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
228 continue;
229 if (__phys_to_pfn(area->phys_addr) > pfn ||
230 __pfn_to_phys(pfn) + size-1 > area->phys_addr + area->size-1)
231 continue;
232 /* we can drop the lock here as we know *area is static */
233 read_unlock(&vmlist_lock);
234 addr = (unsigned long)area->addr;
235 addr += __pfn_to_phys(pfn) - area->phys_addr;
236 return (void __iomem *) (offset + addr);
237 }
238 read_unlock(&vmlist_lock);
239
240 /*
241 * Don't allow RAM to be mapped - this causes problems with ARMv6+
242 */
243 if (WARN_ON(pfn_valid(pfn)))
244 return NULL;
245
246 area = get_vm_area_caller(size, VM_IOREMAP, caller);
247 if (!area)
248 return NULL;
249 addr = (unsigned long)area->addr;
250
251#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
252 if (DOMAIN_IO == 0 &&
253 (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
254 cpu_is_xsc3()) && pfn >= 0x100000 &&
255 !((__pfn_to_phys(pfn) | size | addr) & ~SUPERSECTION_MASK)) {
256 area->flags |= VM_ARM_SECTION_MAPPING;
257 err = remap_area_supersections(addr, pfn, size, type);
258 } else if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) {
259 area->flags |= VM_ARM_SECTION_MAPPING;
260 err = remap_area_sections(addr, pfn, size, type);
261 } else
262#endif
263 err = ioremap_page_range(addr, addr + size, __pfn_to_phys(pfn),
264 __pgprot(type->prot_pte));
265
266 if (err) {
267 vunmap((void *)addr);
268 return NULL;
269 }
270
271 flush_cache_vmap(addr, addr + size);
272 return (void __iomem *) (offset + addr);
273}
274
275void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
276 unsigned int mtype, void *caller)
277{
278 unsigned long last_addr;
279 unsigned long offset = phys_addr & ~PAGE_MASK;
280 unsigned long pfn = __phys_to_pfn(phys_addr);
281
282 /*
283 * Don't allow wraparound or zero size
284 */
285 last_addr = phys_addr + size - 1;
286 if (!size || last_addr < phys_addr)
287 return NULL;
288
289 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
290 caller);
291}
292
293/*
294 * Remap an arbitrary physical address space into the kernel virtual
295 * address space. Needed when the kernel wants to access high addresses
296 * directly.
297 *
298 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
299 * have to convert them into an offset in a page-aligned mapping, but the
300 * caller shouldn't need to know that small detail.
301 */
302void __iomem *
303__arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
304 unsigned int mtype)
305{
306 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
307 __builtin_return_address(0));
308}
309EXPORT_SYMBOL(__arm_ioremap_pfn);
310
311void __iomem * (*arch_ioremap_caller)(unsigned long, size_t,
312 unsigned int, void *) =
313 __arm_ioremap_caller;
314
315void __iomem *
316__arm_ioremap(unsigned long phys_addr, size_t size, unsigned int mtype)
317{
318 return arch_ioremap_caller(phys_addr, size, mtype,
319 __builtin_return_address(0));
320}
321EXPORT_SYMBOL(__arm_ioremap);
322
323/*
324 * Remap an arbitrary physical address space into the kernel virtual
325 * address space as memory. Needed when the kernel wants to execute
326 * code in external memory. This is needed for reprogramming source
327 * clocks that would affect normal memory for example. Please see
328 * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
329 */
330void __iomem *
331__arm_ioremap_exec(unsigned long phys_addr, size_t size, bool cached)
332{
333 unsigned int mtype;
334
335 if (cached)
336 mtype = MT_MEMORY;
337 else
338 mtype = MT_MEMORY_NONCACHED;
339
340 return __arm_ioremap_caller(phys_addr, size, mtype,
341 __builtin_return_address(0));
342}
343
344void __iounmap(volatile void __iomem *io_addr)
345{
346 void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
347 struct vm_struct *vm;
348
349 read_lock(&vmlist_lock);
350 for (vm = vmlist; vm; vm = vm->next) {
351 if (vm->addr > addr)
352 break;
353 if (!(vm->flags & VM_IOREMAP))
354 continue;
355 /* If this is a static mapping we must leave it alone */
356 if ((vm->flags & VM_ARM_STATIC_MAPPING) &&
357 (vm->addr <= addr) && (vm->addr + vm->size > addr)) {
358 read_unlock(&vmlist_lock);
359 return;
360 }
361#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
362 /*
363 * If this is a section based mapping we need to handle it
364 * specially as the VM subsystem does not know how to handle
365 * such a beast.
366 */
367 if ((vm->addr == addr) &&
368 (vm->flags & VM_ARM_SECTION_MAPPING)) {
369 unmap_area_sections((unsigned long)vm->addr, vm->size);
370 break;
371 }
372#endif
373 }
374 read_unlock(&vmlist_lock);
375
376 vunmap(addr);
377}
378
379void (*arch_iounmap)(volatile void __iomem *) = __iounmap;
380
381void __arm_iounmap(volatile void __iomem *io_addr)
382{
383 arch_iounmap(io_addr);
384}
385EXPORT_SYMBOL(__arm_iounmap);