arm64: dts: Revert "specify console via command line"
[linux/fpc-iii.git] / arch / arm / mm / ioremap.c
blob72286f9a4d3047ebaa73cf7b2a15285f3cec49fb
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/arch/arm/mm/ioremap.c
5 * Re-map IO memory to kernel address space so that we can access it.
7 * (C) Copyright 1995 1996 Linus Torvalds
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
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.
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.)
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>
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>
40 #include <asm/mach/map.h>
41 #include <asm/mach/pci.h>
42 #include "mm.h"
45 LIST_HEAD(static_vmlist);
47 static struct static_vm *find_static_vm_paddr(phys_addr_t paddr,
48 size_t size, unsigned int mtype)
50 struct static_vm *svm;
51 struct vm_struct *vm;
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;
60 if (vm->phys_addr > paddr ||
61 paddr + size - 1 > vm->phys_addr + vm->size - 1)
62 continue;
64 return svm;
67 return NULL;
70 struct static_vm *find_static_vm_vaddr(void *vaddr)
72 struct static_vm *svm;
73 struct vm_struct *vm;
75 list_for_each_entry(svm, &static_vmlist, list) {
76 vm = &svm->vm;
78 /* static_vmlist is ascending order */
79 if (vm->addr > vaddr)
80 break;
82 if (vm->addr <= vaddr && vm->addr + vm->size > vaddr)
83 return svm;
86 return NULL;
89 void __init add_static_vm_early(struct static_vm *svm)
91 struct static_vm *curr_svm;
92 struct vm_struct *vm;
93 void *vaddr;
95 vm = &svm->vm;
96 vm_area_add_early(vm);
97 vaddr = vm->addr;
99 list_for_each_entry(curr_svm, &static_vmlist, list) {
100 vm = &curr_svm->vm;
102 if (vm->addr > vaddr)
103 break;
105 list_add_tail(&svm->list, &curr_svm->list);
108 int ioremap_page(unsigned long virt, unsigned long phys,
109 const struct mem_type *mtype)
111 return ioremap_page_range(virt, virt + PAGE_SIZE, phys,
112 __pgprot(mtype->prot_pte));
114 EXPORT_SYMBOL(ioremap_page);
116 void __check_vmalloc_seq(struct mm_struct *mm)
118 unsigned int seq;
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);
130 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
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.
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.
141 static void unmap_area_sections(unsigned long virt, unsigned long size)
143 unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
144 pgd_t *pgd;
145 pud_t *pud;
146 pmd_t *pmdp;
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;
155 if (!pmd_none(pmd)) {
157 * Clear the PMD from the page table, and
158 * increment the vmalloc sequence so others
159 * notice this change.
161 * Note: this is still racy on SMP machines.
163 pmd_clear(pmdp);
164 init_mm.context.vmalloc_seq++;
167 * Free the page table, if there was one.
169 if ((pmd_val(pmd) & PMD_TYPE_MASK) == PMD_TYPE_TABLE)
170 pte_free_kernel(&init_mm, pmd_page_vaddr(pmd));
173 addr += PMD_SIZE;
174 pmdp += 2;
175 } while (addr < end);
178 * Ensure that the active_mm is up to date - we want to
179 * catch any use-after-iounmap cases.
181 if (current->active_mm->context.vmalloc_seq != init_mm.context.vmalloc_seq)
182 __check_vmalloc_seq(current->active_mm);
184 flush_tlb_kernel_range(virt, end);
187 static int
188 remap_area_sections(unsigned long virt, unsigned long pfn,
189 size_t size, const struct mem_type *type)
191 unsigned long addr = virt, end = virt + size;
192 pgd_t *pgd;
193 pud_t *pud;
194 pmd_t *pmd;
197 * Remove and free any PTE-based mapping, and
198 * sync the current kernel mapping.
200 unmap_area_sections(virt, size);
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);
212 addr += PMD_SIZE;
213 pmd += 2;
214 } while (addr < end);
216 return 0;
219 static int
220 remap_area_supersections(unsigned long virt, unsigned long pfn,
221 size_t size, const struct mem_type *type)
223 unsigned long addr = virt, end = virt + size;
224 pgd_t *pgd;
225 pud_t *pud;
226 pmd_t *pmd;
229 * Remove and free any PTE-based mapping, and
230 * sync the current kernel mapping.
232 unmap_area_sections(virt, size);
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;
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;
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);
249 addr += PMD_SIZE;
250 pmd += 2;
253 pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
254 } while (addr < end);
256 return 0;
258 #endif
260 static void __iomem * __arm_ioremap_pfn_caller(unsigned long pfn,
261 unsigned long offset, size_t size, unsigned int mtype, void *caller)
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);
269 #ifndef CONFIG_ARM_LPAE
271 * High mappings must be supersection aligned
273 if (pfn >= 0x100000 && (paddr & ~SUPERSECTION_MASK))
274 return NULL;
275 #endif
277 type = get_mem_type(mtype);
278 if (!type)
279 return NULL;
282 * Page align the mapping size, taking account of any offset.
284 size = PAGE_ALIGN(offset + size);
287 * Try to reuse one of the static mapping whenever possible.
289 if (size && !(sizeof(phys_addr_t) == 4 && pfn >= 0x100000)) {
290 struct static_vm *svm;
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);
301 * Don't allow RAM to be mapped with mismatched attributes - this
302 * causes problems with ARMv6+
304 if (WARN_ON(pfn_valid(pfn) && mtype != MT_MEMORY_RW))
305 return NULL;
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;
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));
328 if (err) {
329 vunmap((void *)addr);
330 return NULL;
333 flush_cache_vmap(addr, addr + size);
334 return (void __iomem *) (offset + addr);
337 void __iomem *__arm_ioremap_caller(phys_addr_t phys_addr, size_t size,
338 unsigned int mtype, void *caller)
340 phys_addr_t last_addr;
341 unsigned long offset = phys_addr & ~PAGE_MASK;
342 unsigned long pfn = __phys_to_pfn(phys_addr);
345 * Don't allow wraparound or zero size
347 last_addr = phys_addr + size - 1;
348 if (!size || last_addr < phys_addr)
349 return NULL;
351 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
352 caller);
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.
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.
364 void __iomem *
365 __arm_ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
366 unsigned int mtype)
368 return __arm_ioremap_pfn_caller(pfn, offset, size, mtype,
369 __builtin_return_address(0));
371 EXPORT_SYMBOL(__arm_ioremap_pfn);
373 void __iomem * (*arch_ioremap_caller)(phys_addr_t, size_t,
374 unsigned int, void *) =
375 __arm_ioremap_caller;
377 void __iomem *ioremap(resource_size_t res_cookie, size_t size)
379 return arch_ioremap_caller(res_cookie, size, MT_DEVICE,
380 __builtin_return_address(0));
382 EXPORT_SYMBOL(ioremap);
384 void __iomem *ioremap_cache(resource_size_t res_cookie, size_t size)
386 return arch_ioremap_caller(res_cookie, size, MT_DEVICE_CACHED,
387 __builtin_return_address(0));
389 EXPORT_SYMBOL(ioremap_cache);
391 void __iomem *ioremap_wc(resource_size_t res_cookie, size_t size)
393 return arch_ioremap_caller(res_cookie, size, MT_DEVICE_WC,
394 __builtin_return_address(0));
396 EXPORT_SYMBOL(ioremap_wc);
399 * Remap an arbitrary physical address space into the kernel virtual
400 * address space as memory. Needed when the kernel wants to execute
401 * code in external memory. This is needed for reprogramming source
402 * clocks that would affect normal memory for example. Please see
403 * CONFIG_GENERIC_ALLOCATOR for allocating external memory.
405 void __iomem *
406 __arm_ioremap_exec(phys_addr_t phys_addr, size_t size, bool cached)
408 unsigned int mtype;
410 if (cached)
411 mtype = MT_MEMORY_RWX;
412 else
413 mtype = MT_MEMORY_RWX_NONCACHED;
415 return __arm_ioremap_caller(phys_addr, size, mtype,
416 __builtin_return_address(0));
419 void *arch_memremap_wb(phys_addr_t phys_addr, size_t size)
421 return (__force void *)arch_ioremap_caller(phys_addr, size,
422 MT_MEMORY_RW,
423 __builtin_return_address(0));
426 void __iounmap(volatile void __iomem *io_addr)
428 void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
429 struct static_vm *svm;
431 /* If this is a static mapping, we must leave it alone */
432 svm = find_static_vm_vaddr(addr);
433 if (svm)
434 return;
436 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
438 struct vm_struct *vm;
440 vm = find_vm_area(addr);
443 * If this is a section based mapping we need to handle it
444 * specially as the VM subsystem does not know how to handle
445 * such a beast.
447 if (vm && (vm->flags & VM_ARM_SECTION_MAPPING))
448 unmap_area_sections((unsigned long)vm->addr, vm->size);
450 #endif
452 vunmap(addr);
455 void (*arch_iounmap)(volatile void __iomem *) = __iounmap;
457 void iounmap(volatile void __iomem *cookie)
459 arch_iounmap(cookie);
461 EXPORT_SYMBOL(iounmap);
463 #ifdef CONFIG_PCI
464 static int pci_ioremap_mem_type = MT_DEVICE;
466 void pci_ioremap_set_mem_type(int mem_type)
468 pci_ioremap_mem_type = mem_type;
471 int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr)
473 BUG_ON(offset + SZ_64K - 1 > IO_SPACE_LIMIT);
475 return ioremap_page_range(PCI_IO_VIRT_BASE + offset,
476 PCI_IO_VIRT_BASE + offset + SZ_64K,
477 phys_addr,
478 __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte));
480 EXPORT_SYMBOL_GPL(pci_ioremap_io);
482 void __iomem *pci_remap_cfgspace(resource_size_t res_cookie, size_t size)
484 return arch_ioremap_caller(res_cookie, size, MT_UNCACHED,
485 __builtin_return_address(0));
487 EXPORT_SYMBOL_GPL(pci_remap_cfgspace);
488 #endif
491 * Must be called after early_fixmap_init
493 void __init early_ioremap_init(void)
495 early_ioremap_setup();