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v3.1
 
  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/cputype.h>
 30#include <asm/cacheflush.h>
 
 31#include <asm/mmu_context.h>
 32#include <asm/pgalloc.h>
 33#include <asm/tlbflush.h>
 34#include <asm/sizes.h>
 35
 36#include <asm/mach/map.h>
 
 37#include "mm.h"
 38
 39/*
 40 * Used by ioremap() and iounmap() code to mark (super)section-mapped
 41 * I/O regions in vm_struct->flags field.
 42 */
 43#define VM_ARM_SECTION_MAPPING	0x80000000
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 44
 45int ioremap_page(unsigned long virt, unsigned long phys,
 46		 const struct mem_type *mtype)
 47{
 48	return ioremap_page_range(virt, virt + PAGE_SIZE, phys,
 49				  __pgprot(mtype->prot_pte));
 50}
 51EXPORT_SYMBOL(ioremap_page);
 52
 53void __check_kvm_seq(struct mm_struct *mm)
 54{
 55	unsigned int seq;
 56
 57	do {
 58		seq = init_mm.context.kvm_seq;
 59		memcpy(pgd_offset(mm, VMALLOC_START),
 60		       pgd_offset_k(VMALLOC_START),
 61		       sizeof(pgd_t) * (pgd_index(VMALLOC_END) -
 62					pgd_index(VMALLOC_START)));
 63		mm->context.kvm_seq = seq;
 64	} while (seq != init_mm.context.kvm_seq);
 65}
 66
 67#ifndef CONFIG_SMP
 68/*
 69 * Section support is unsafe on SMP - If you iounmap and ioremap a region,
 70 * the other CPUs will not see this change until their next context switch.
 71 * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
 72 * which requires the new ioremap'd region to be referenced, the CPU will
 73 * reference the _old_ region.
 74 *
 75 * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
 76 * mask the size back to 1MB aligned or we will overflow in the loop below.
 77 */
 78static void unmap_area_sections(unsigned long virt, unsigned long size)
 79{
 80	unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
 81	pgd_t *pgd;
 
 
 82
 83	flush_cache_vunmap(addr, end);
 84	pgd = pgd_offset_k(addr);
 
 
 85	do {
 86		pmd_t pmd, *pmdp = pmd_offset(pgd, addr);
 87
 88		pmd = *pmdp;
 89		if (!pmd_none(pmd)) {
 90			/*
 91			 * Clear the PMD from the page table, and
 92			 * increment the kvm sequence so others
 93			 * notice this change.
 94			 *
 95			 * Note: this is still racy on SMP machines.
 96			 */
 97			pmd_clear(pmdp);
 98			init_mm.context.kvm_seq++;
 99
100			/*
101			 * Free the page table, if there was one.
102			 */
103			if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
104				pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
105		}
106
107		addr += PGDIR_SIZE;
108		pgd++;
109	} while (addr < end);
110
111	/*
112	 * Ensure that the active_mm is up to date - we want to
113	 * catch any use-after-iounmap cases.
114	 */
115	if (current->active_mm->context.kvm_seq != init_mm.context.kvm_seq)
116		__check_kvm_seq(current->active_mm);
117
118	flush_tlb_kernel_range(virt, end);
119}
120
121static int
122remap_area_sections(unsigned long virt, unsigned long pfn,
123		    size_t size, const struct mem_type *type)
124{
125	unsigned long addr = virt, end = virt + size;
126	pgd_t *pgd;
 
 
127
128	/*
129	 * Remove and free any PTE-based mapping, and
130	 * sync the current kernel mapping.
131	 */
132	unmap_area_sections(virt, size);
133
134	pgd = pgd_offset_k(addr);
 
 
135	do {
136		pmd_t *pmd = pmd_offset(pgd, addr);
137
138		pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
139		pfn += SZ_1M >> PAGE_SHIFT;
140		pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
141		pfn += SZ_1M >> PAGE_SHIFT;
142		flush_pmd_entry(pmd);
143
144		addr += PGDIR_SIZE;
145		pgd++;
146	} while (addr < end);
147
148	return 0;
149}
150
151static int
152remap_area_supersections(unsigned long virt, unsigned long pfn,
153			 size_t size, const struct mem_type *type)
154{
155	unsigned long addr = virt, end = virt + size;
156	pgd_t *pgd;
 
 
157
158	/*
159	 * Remove and free any PTE-based mapping, and
160	 * sync the current kernel mapping.
161	 */
162	unmap_area_sections(virt, size);
163
164	pgd = pgd_offset_k(virt);
 
 
165	do {
166		unsigned long super_pmd_val, i;
167
168		super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
169				PMD_SECT_SUPER;
170		super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
171
172		for (i = 0; i < 8; i++) {
173			pmd_t *pmd = pmd_offset(pgd, addr);
174
175			pmd[0] = __pmd(super_pmd_val);
176			pmd[1] = __pmd(super_pmd_val);
177			flush_pmd_entry(pmd);
178
179			addr += PGDIR_SIZE;
180			pgd++;
181		}
182
183		pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
184	} while (addr < end);
185
186	return 0;
187}
188#endif
189
190void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
191	unsigned long offset, size_t size, unsigned int mtype, void *caller)
192{
193	const struct mem_type *type;
194	int err;
195	unsigned long addr;
196 	struct vm_struct * area;
 
197
 
198	/*
199	 * High mappings must be supersection aligned
200	 */
201	if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK))
202		return NULL;
203
204	/*
205	 * Don't allow RAM to be mapped - this causes problems with ARMv6+
206	 */
207	if (WARN_ON(pfn_valid(pfn)))
208		return NULL;
 
209
210	type = get_mem_type(mtype);
211	if (!type)
212		return NULL;
213
214	/*
215	 * Page align the mapping size, taking account of any offset.
216	 */
217	size = PAGE_ALIGN(offset + size);
218
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
219	area = get_vm_area_caller(size, VM_IOREMAP, caller);
220 	if (!area)
221 		return NULL;
222 	addr = (unsigned long)area->addr;
 
223
224#ifndef CONFIG_SMP
225	if (DOMAIN_IO == 0 &&
226	    (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
227	       cpu_is_xsc3()) && pfn >= 0x100000 &&
228	       !((__pfn_to_phys(pfn) | size | addr) & ~SUPERSECTION_MASK)) {
229		area->flags |= VM_ARM_SECTION_MAPPING;
230		err = remap_area_supersections(addr, pfn, size, type);
231	} else if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) {
232		area->flags |= VM_ARM_SECTION_MAPPING;
233		err = remap_area_sections(addr, pfn, size, type);
234	} else
235#endif
236		err = ioremap_page_range(addr, addr + size, __pfn_to_phys(pfn),
237					 __pgprot(type->prot_pte));
238
239	if (err) {
240 		vunmap((void *)addr);
241 		return NULL;
242 	}
243
244	flush_cache_vmap(addr, addr + size);
245	return (void __iomem *) (offset + addr);
246}
247
248void __iomem *__arm_ioremap_caller(unsigned long phys_addr, size_t size,
249	unsigned int mtype, void *caller)
250{
251	unsigned long last_addr;
252 	unsigned long offset = phys_addr & ~PAGE_MASK;
253 	unsigned long pfn = __phys_to_pfn(phys_addr);
254
255 	/*
256 	 * Don't allow wraparound or zero size
257	 */
258	last_addr = phys_addr + size - 1;
259	if (!size || last_addr < phys_addr)
260		return NULL;
261
262	return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
263			caller);
264}
265
266/*
267 * Remap an arbitrary physical address space into the kernel virtual
268 * address space. Needed when the kernel wants to access high addresses
269 * directly.
270 *
271 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
272 * have to convert them into an offset in a page-aligned mapping, but the
273 * caller shouldn't need to know that small detail.
274 */
275void __iomem *
276__arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
277		  unsigned int mtype)
278{
279	return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
280			__builtin_return_address(0));
281}
282EXPORT_SYMBOL(__arm_ioremap_pfn);
283
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
284void __iomem *
285__arm_ioremap(unsigned long phys_addr, size_t size, unsigned int mtype)
286{
 
 
 
 
 
 
 
287	return __arm_ioremap_caller(phys_addr, size, mtype,
288			__builtin_return_address(0));
289}
290EXPORT_SYMBOL(__arm_ioremap);
 
 
 
 
 
 
291
292void __iounmap(volatile void __iomem *io_addr)
293{
294	void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
295#ifndef CONFIG_SMP
296	struct vm_struct **p, *tmp;
297
298	/*
299	 * If this is a section based mapping we need to handle it
300	 * specially as the VM subsystem does not know how to handle
301	 * such a beast. We need the lock here b/c we need to clear
302	 * all the mappings before the area can be reclaimed
303	 * by someone else.
304	 */
305	write_lock(&vmlist_lock);
306	for (p = &vmlist ; (tmp = *p) ; p = &tmp->next) {
307		if ((tmp->flags & VM_IOREMAP) && (tmp->addr == addr)) {
308			if (tmp->flags & VM_ARM_SECTION_MAPPING) {
309				unmap_area_sections((unsigned long)tmp->addr,
310						    tmp->size);
311			}
312			break;
313		}
 
 
314	}
315	write_unlock(&vmlist_lock);
316#endif
317
318	vunmap(addr);
319}
320EXPORT_SYMBOL(__iounmap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v5.4
  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/mm.h>
 27#include <linux/vmalloc.h>
 28#include <linux/io.h>
 29#include <linux/sizes.h>
 30
 31#include <asm/cp15.h>
 32#include <asm/cputype.h>
 33#include <asm/cacheflush.h>
 34#include <asm/early_ioremap.h>
 35#include <asm/mmu_context.h>
 36#include <asm/pgalloc.h>
 37#include <asm/tlbflush.h>
 38#include <asm/system_info.h>
 39
 40#include <asm/mach/map.h>
 41#include <asm/mach/pci.h>
 42#include "mm.h"
 43
 44
 45LIST_HEAD(static_vmlist);
 46
 47static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
 48			size_t size, unsigned int mtype)
 49{
 50	struct static_vm *svm;
 51	struct vm_struct *vm;
 52
 53	list_for_each_entry(svm, &static_vmlist, list) {
 54		vm = &svm->vm;
 55		if (!(vm->flags & VM_ARM_STATIC_MAPPING))
 56			continue;
 57		if ((vm->flags & VM_ARM_MTYPE_MASK) != VM_ARM_MTYPE(mtype))
 58			continue;
 59
 60		if (vm->phys_addr > paddr ||
 61			paddr + size - 1 > vm->phys_addr + vm->size - 1)
 62			continue;
 63
 64		return svm;
 65	}
 66
 67	return NULL;
 68}
 69
 70struct static_vm *find_static_vm_vaddr(void *vaddr)
 71{
 72	struct static_vm *svm;
 73	struct vm_struct *vm;
 74
 75	list_for_each_entry(svm, &static_vmlist, list) {
 76		vm = &svm->vm;
 77
 78		/* static_vmlist is ascending order */
 79		if (vm->addr > vaddr)
 80			break;
 81
 82		if (vm->addr <= vaddr && vm->addr + vm->size > vaddr)
 83			return svm;
 84	}
 85
 86	return NULL;
 87}
 88
 89void __init add_static_vm_early(struct static_vm *svm)
 90{
 91	struct static_vm *curr_svm;
 92	struct vm_struct *vm;
 93	void *vaddr;
 94
 95	vm = &svm->vm;
 96	vm_area_add_early(vm);
 97	vaddr = vm->addr;
 98
 99	list_for_each_entry(curr_svm, &static_vmlist, list) {
100		vm = &curr_svm->vm;
101
102		if (vm->addr > vaddr)
103			break;
104	}
105	list_add_tail(&svm->list, &curr_svm->list);
106}
107
108int ioremap_page(unsigned long virt, unsigned long phys,
109		 const struct mem_type *mtype)
110{
111	return ioremap_page_range(virt, virt + PAGE_SIZE, phys,
112				  __pgprot(mtype->prot_pte));
113}
114EXPORT_SYMBOL(ioremap_page);
115
116void __check_vmalloc_seq(struct mm_struct *mm)
117{
118	unsigned int seq;
119
120	do {
121		seq = init_mm.context.vmalloc_seq;
122		memcpy(pgd_offset(mm, VMALLOC_START),
123		       pgd_offset_k(VMALLOC_START),
124		       sizeof(pgd_t) * (pgd_index(VMALLOC_END) -
125					pgd_index(VMALLOC_START)));
126		mm->context.vmalloc_seq = seq;
127	} while (seq != init_mm.context.vmalloc_seq);
128}
129
130#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
131/*
132 * Section support is unsafe on SMP - If you iounmap and ioremap a region,
133 * the other CPUs will not see this change until their next context switch.
134 * Meanwhile, (eg) if an interrupt comes in on one of those other CPUs
135 * which requires the new ioremap'd region to be referenced, the CPU will
136 * reference the _old_ region.
137 *
138 * Note that get_vm_area_caller() allocates a guard 4K page, so we need to
139 * mask the size back to 1MB aligned or we will overflow in the loop below.
140 */
141static void unmap_area_sections(unsigned long virt, unsigned long size)
142{
143	unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
144	pgd_t *pgd;
145	pud_t *pud;
146	pmd_t *pmdp;
147
148	flush_cache_vunmap(addr, end);
149	pgd = pgd_offset_k(addr);
150	pud = pud_offset(pgd, addr);
151	pmdp = pmd_offset(pud, addr);
152	do {
153		pmd_t pmd = *pmdp;
154
 
155		if (!pmd_none(pmd)) {
156			/*
157			 * Clear the PMD from the page table, and
158			 * increment the vmalloc sequence so others
159			 * notice this change.
160			 *
161			 * Note: this is still racy on SMP machines.
162			 */
163			pmd_clear(pmdp);
164			init_mm.context.vmalloc_seq++;
165
166			/*
167			 * Free the page table, if there was one.
168			 */
169			if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
170				pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
171		}
172
173		addr += PMD_SIZE;
174		pmdp += 2;
175	} while (addr < end);
176
177	/*
178	 * Ensure that the active_mm is up to date - we want to
179	 * catch any use-after-iounmap cases.
180	 */
181	if (current->active_mm->context.vmalloc_seq != init_mm.context.vmalloc_seq)
182		__check_vmalloc_seq(current->active_mm);
183
184	flush_tlb_kernel_range(virt, end);
185}
186
187static int
188remap_area_sections(unsigned long virt, unsigned long pfn,
189		    size_t size, const struct mem_type *type)
190{
191	unsigned long addr = virt, end = virt + size;
192	pgd_t *pgd;
193	pud_t *pud;
194	pmd_t *pmd;
195
196	/*
197	 * Remove and free any PTE-based mapping, and
198	 * sync the current kernel mapping.
199	 */
200	unmap_area_sections(virt, size);
201
202	pgd = pgd_offset_k(addr);
203	pud = pud_offset(pgd, addr);
204	pmd = pmd_offset(pud, addr);
205	do {
 
 
206		pmd[0] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
207		pfn += SZ_1M >> PAGE_SHIFT;
208		pmd[1] = __pmd(__pfn_to_phys(pfn) | type->prot_sect);
209		pfn += SZ_1M >> PAGE_SHIFT;
210		flush_pmd_entry(pmd);
211
212		addr += PMD_SIZE;
213		pmd += 2;
214	} while (addr < end);
215
216	return 0;
217}
218
219static int
220remap_area_supersections(unsigned long virt, unsigned long pfn,
221			 size_t size, const struct mem_type *type)
222{
223	unsigned long addr = virt, end = virt + size;
224	pgd_t *pgd;
225	pud_t *pud;
226	pmd_t *pmd;
227
228	/*
229	 * Remove and free any PTE-based mapping, and
230	 * sync the current kernel mapping.
231	 */
232	unmap_area_sections(virt, size);
233
234	pgd = pgd_offset_k(virt);
235	pud = pud_offset(pgd, addr);
236	pmd = pmd_offset(pud, addr);
237	do {
238		unsigned long super_pmd_val, i;
239
240		super_pmd_val = __pfn_to_phys(pfn) | type->prot_sect |
241				PMD_SECT_SUPER;
242		super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
243
244		for (i = 0; i < 8; i++) {
 
 
245			pmd[0] = __pmd(super_pmd_val);
246			pmd[1] = __pmd(super_pmd_val);
247			flush_pmd_entry(pmd);
248
249			addr += PMD_SIZE;
250			pmd += 2;
251		}
252
253		pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
254	} while (addr < end);
255
256	return 0;
257}
258#endif
259
260static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
261	unsigned long offset, size_t size, unsigned int mtype, void *caller)
262{
263	const struct mem_type *type;
264	int err;
265	unsigned long addr;
266	struct vm_struct *area;
267	phys_addr_t paddr = __pfn_to_phys(pfn);
268
269#ifndef CONFIG_ARM_LPAE
270	/*
271	 * High mappings must be supersection aligned
272	 */
273	if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
 
 
 
 
 
 
274		return NULL;
275#endif
276
277	type = get_mem_type(mtype);
278	if (!type)
279		return NULL;
280
281	/*
282	 * Page align the mapping size, taking account of any offset.
283	 */
284	size = PAGE_ALIGN(offset + size);
285
286	/*
287	 * Try to reuse one of the static mapping whenever possible.
288	 */
289	if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
290		struct static_vm *svm;
291
292		svm = find_static_vm_paddr(paddr, size, mtype);
293		if (svm) {
294			addr = (unsigned long)svm->vm.addr;
295			addr += paddr - svm->vm.phys_addr;
296			return (void __iomem *) (offset + addr);
297		}
298	}
299
300	/*
301	 * Don't allow RAM to be mapped with mismatched attributes - this
302	 * causes problems with ARMv6+
303	 */
304	if (WARN_ON(pfn_valid(pfn) && mtype != MT_MEMORY_RW))
305		return NULL;
306
307	area = get_vm_area_caller(size, VM_IOREMAP, caller);
308 	if (!area)
309 		return NULL;
310 	addr = (unsigned long)area->addr;
311	area->phys_addr = paddr;
312
313#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
314	if (DOMAIN_IO == 0 &&
315	    (((cpu_architecture() >= CPU_ARCH_ARMv6) && (get_cr() & CR_XP)) ||
316	       cpu_is_xsc3()) && pfn >= 0x100000 &&
317	       !((paddr | size | addr) & ~SUPERSECTION_MASK)) {
318		area->flags |= VM_ARM_SECTION_MAPPING;
319		err = remap_area_supersections(addr, pfn, size, type);
320	} else if (!((paddr | size | addr) & ~PMD_MASK)) {
321		area->flags |= VM_ARM_SECTION_MAPPING;
322		err = remap_area_sections(addr, pfn, size, type);
323	} else
324#endif
325		err = ioremap_page_range(addr, addr + size, paddr,
326					 __pgprot(type->prot_pte));
327
328	if (err) {
329 		vunmap((void *)addr);
330 		return NULL;
331 	}
332
333	flush_cache_vmap(addr, addr + size);
334	return (void __iomem *) (offset + addr);
335}
336
337void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
338	unsigned int mtype, void *caller)
339{
340	phys_addr_t last_addr;
341 	unsigned long offset = phys_addr & ~PAGE_MASK;
342 	unsigned long pfn = __phys_to_pfn(phys_addr);
343
344 	/*
345 	 * Don't allow wraparound or zero size
346	 */
347	last_addr = phys_addr + size - 1;
348	if (!size || last_addr < phys_addr)
349		return NULL;
350
351	return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
352			caller);
353}
354
355/*
356 * Remap an arbitrary physical address space into the kernel virtual
357 * address space. Needed when the kernel wants to access high addresses
358 * directly.
359 *
360 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
361 * have to convert them into an offset in a page-aligned mapping, but the
362 * caller shouldn't need to know that small detail.
363 */
364void __iomem *
365__arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
366		  unsigned int mtype)
367{
368	return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
369					__builtin_return_address(0));
370}
371EXPORT_SYMBOL(__arm_ioremap_pfn);
372
373void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
374				      unsigned int, void *) =
375	__arm_ioremap_caller;
376
377void __iomem *ioremap(resource_size_t res_cookie, size_t size)
378{
379	return arch_ioremap_caller(res_cookie, size, MT_DEVICE,
380				   __builtin_return_address(0));
381}
382EXPORT_SYMBOL(ioremap);
383
384void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
385	__alias(ioremap_cached);
386
387void __iomem *ioremap_cached(resource_size_t res_cookie, size_t size)
388{
389	return arch_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
390				   __builtin_return_address(0));
391}
392EXPORT_SYMBOL(ioremap_cache);
393EXPORT_SYMBOL(ioremap_cached);
394
395void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
396{
397	return arch_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
398				   __builtin_return_address(0));
399}
400EXPORT_SYMBOL(ioremap_wc);
401
402/*
403 * Remap an arbitrary physical address space into the kernel virtual
404 * address space as memory. Needed when the kernel wants to execute
405 * code in external memory. This is needed for reprogramming source
406 * clocks that would affect normal memory for example. Please see
407 * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
408 */
409void __iomem *
410__arm_ioremap_exec(phys_addr_t phys_addr, size_t size, bool cached)
411{
412	unsigned int mtype;
413
414	if (cached)
415		mtype = MT_MEMORY_RWX;
416	else
417		mtype = MT_MEMORY_RWX_NONCACHED;
418
419	return __arm_ioremap_caller(phys_addr, size, mtype,
420			__builtin_return_address(0));
421}
422
423void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
424{
425	return (__force void *)arch_ioremap_caller(phys_addr, size,
426						   MT_MEMORY_RW,
427						   __builtin_return_address(0));
428}
429
430void __iounmap(volatile void __iomem *io_addr)
431{
432	void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
433	struct static_vm *svm;
 
434
435	/* If this is a static mapping, we must leave it alone */
436	svm = find_static_vm_vaddr(addr);
437	if (svm)
438		return;
439
440#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
441	{
442		struct vm_struct *vm;
443
444		vm = find_vm_area(addr);
445
446		/*
447		 * If this is a section based mapping we need to handle it
448		 * specially as the VM subsystem does not know how to handle
449		 * such a beast.
450		 */
451		if (vm && (vm->flags & VM_ARM_SECTION_MAPPING))
452			unmap_area_sections((unsigned long)vm->addr, vm->size);
453	}
 
454#endif
455
456	vunmap(addr);
457}
458
459void (*arch_iounmap)(volatile void __iomem *) = __iounmap;
460
461void iounmap(volatile void __iomem *cookie)
462{
463	arch_iounmap(cookie);
464}
465EXPORT_SYMBOL(iounmap);
466
467#ifdef CONFIG_PCI
468static int pci_ioremap_mem_type = MT_DEVICE;
469
470void pci_ioremap_set_mem_type(int mem_type)
471{
472	pci_ioremap_mem_type = mem_type;
473}
474
475int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr)
476{
477	BUG_ON(offset + SZ_64K - 1 > IO_SPACE_LIMIT);
478
479	return ioremap_page_range(PCI_IO_VIRT_BASE + offset,
480				  PCI_IO_VIRT_BASE + offset + SZ_64K,
481				  phys_addr,
482				  __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte));
483}
484EXPORT_SYMBOL_GPL(pci_ioremap_io);
485
486void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
487{
488	return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
489				   __builtin_return_address(0));
490}
491EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
492#endif
493
494/*
495 * Must be called after early_fixmap_init
496 */
497void __init early_ioremap_init(void)
498{
499	early_ioremap_setup();
500}