2 * Based on arch/arm/mm/ioremap.c
4 * (C) Copyright 1995 1996 Linus Torvalds
5 * Hacked for ARM by Phil Blundell <philb@gnu.org>
6 * Hacked to allow all architectures to build, and various cleanups
8 * Copyright (C) 2012 ARM Ltd.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include <linux/export.h>
25 #include <linux/vmalloc.h>
28 #include <asm/fixmap.h>
29 #include <asm/tlbflush.h>
30 #include <asm/pgalloc.h>
32 static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
33 pgprot_t prot, void *caller)
35 unsigned long last_addr;
36 unsigned long offset = phys_addr & ~PAGE_MASK;
39 struct vm_struct *area;
42 * Page align the mapping address and size, taking account of any
45 phys_addr &= PAGE_MASK;
46 size = PAGE_ALIGN(size + offset);
49 * Don't allow wraparound, zero size or outside PHYS_MASK.
51 last_addr = phys_addr + size - 1;
52 if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK))
56 * Don't allow RAM to be mapped.
58 if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
61 area = get_vm_area_caller(size, VM_IOREMAP, caller);
64 addr = (unsigned long)area->addr;
66 err = ioremap_page_range(addr, addr + size, phys_addr, prot);
72 return (void __iomem *)(offset + addr);
75 void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
77 return __ioremap_caller(phys_addr, size, prot,
78 __builtin_return_address(0));
80 EXPORT_SYMBOL(__ioremap);
82 void __iounmap(volatile void __iomem *io_addr)
84 unsigned long addr = (unsigned long)io_addr & PAGE_MASK;
87 * We could get an address outside vmalloc range in case
88 * of ioremap_cache() reusing a RAM mapping.
90 if (VMALLOC_START <= addr && addr < VMALLOC_END)
93 EXPORT_SYMBOL(__iounmap);
95 void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
97 /* For normal memory we already have a cacheable mapping. */
98 if (pfn_valid(__phys_to_pfn(phys_addr)))
99 return (void __iomem *)__phys_to_virt(phys_addr);
101 return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
102 __builtin_return_address(0));
104 EXPORT_SYMBOL(ioremap_cache);
106 #ifndef CONFIG_ARM64_64K_PAGES
107 static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
110 static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
115 pgd = pgd_offset_k(addr);
116 BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));
118 pud = pud_offset(pgd, addr);
119 BUG_ON(pud_none(*pud) || pud_bad(*pud));
121 return pmd_offset(pud, addr);
124 static inline pte_t * __init early_ioremap_pte(unsigned long addr)
126 pmd_t *pmd = early_ioremap_pmd(addr);
128 BUG_ON(pmd_none(*pmd) || pmd_bad(*pmd));
130 return pte_offset_kernel(pmd, addr);
133 void __init early_ioremap_init(void)
137 pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
138 #ifndef CONFIG_ARM64_64K_PAGES
139 /* need to populate pmd for 4k pagesize only */
140 pmd_populate_kernel(&init_mm, pmd, bm_pte);
143 * The boot-ioremap range spans multiple pmds, for which
144 * we are not prepared:
146 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
147 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
149 if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
151 pr_warn("pmd %p != %p\n",
152 pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
153 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
154 fix_to_virt(FIX_BTMAP_BEGIN));
155 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
156 fix_to_virt(FIX_BTMAP_END));
158 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
159 pr_warn("FIX_BTMAP_BEGIN: %d\n",
163 early_ioremap_setup();
166 void __init __early_set_fixmap(enum fixed_addresses idx,
167 phys_addr_t phys, pgprot_t flags)
169 unsigned long addr = __fix_to_virt(idx);
172 if (idx >= __end_of_fixed_addresses) {
177 pte = early_ioremap_pte(addr);
179 if (pgprot_val(flags))
180 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
182 pte_clear(&init_mm, addr, pte);
183 flush_tlb_kernel_range(addr, addr+PAGE_SIZE);