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 void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
88 EXPORT_SYMBOL(__iounmap);
90 void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
92 /* For normal memory we already have a cacheable mapping. */
93 if (pfn_valid(__phys_to_pfn(phys_addr)))
94 return (void __iomem *)__phys_to_virt(phys_addr);
96 return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
97 __builtin_return_address(0));
99 EXPORT_SYMBOL(ioremap_cache);
101 #ifndef CONFIG_ARM64_64K_PAGES
102 static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;
105 static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
110 pgd = pgd_offset_k(addr);
111 BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));
113 pud = pud_offset(pgd, addr);
114 BUG_ON(pud_none(*pud) || pud_bad(*pud));
116 return pmd_offset(pud, addr);
119 static inline pte_t * __init early_ioremap_pte(unsigned long addr)
121 pmd_t *pmd = early_ioremap_pmd(addr);
123 BUG_ON(pmd_none(*pmd) || pmd_bad(*pmd));
125 return pte_offset_kernel(pmd, addr);
128 void __init early_ioremap_init(void)
132 pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
133 #ifndef CONFIG_ARM64_64K_PAGES
134 /* need to populate pmd for 4k pagesize only */
135 pmd_populate_kernel(&init_mm, pmd, bm_pte);
138 * The boot-ioremap range spans multiple pmds, for which
139 * we are not prepared:
141 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
142 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
144 if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
146 pr_warn("pmd %p != %p\n",
147 pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
148 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
149 fix_to_virt(FIX_BTMAP_BEGIN));
150 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
151 fix_to_virt(FIX_BTMAP_END));
153 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
154 pr_warn("FIX_BTMAP_BEGIN: %d\n",
158 early_ioremap_setup();
161 void __init __early_set_fixmap(enum fixed_addresses idx,
162 phys_addr_t phys, pgprot_t flags)
164 unsigned long addr = __fix_to_virt(idx);
167 if (idx >= __end_of_fixed_addresses) {
172 pte = early_ioremap_pte(addr);
174 if (pgprot_val(flags))
175 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
177 pte_clear(&init_mm, addr, pte);
178 flush_tlb_kernel_range(addr, addr+PAGE_SIZE);