diff options
Diffstat (limited to 'kernel/arch/arm64/mm/ioremap.c')
-rw-r--r-- | kernel/arch/arm64/mm/ioremap.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/kernel/arch/arm64/mm/ioremap.c b/kernel/arch/arm64/mm/ioremap.c new file mode 100644 index 000000000..01e88c8bc --- /dev/null +++ b/kernel/arch/arm64/mm/ioremap.c @@ -0,0 +1,113 @@ +/* + * Based on arch/arm/mm/ioremap.c + * + * (C) Copyright 1995 1996 Linus Torvalds + * Hacked for ARM by Phil Blundell <philb@gnu.org> + * Hacked to allow all architectures to build, and various cleanups + * by Russell King + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/io.h> + +#include <asm/fixmap.h> +#include <asm/tlbflush.h> +#include <asm/pgalloc.h> + +static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size, + pgprot_t prot, void *caller) +{ + unsigned long last_addr; + unsigned long offset = phys_addr & ~PAGE_MASK; + int err; + unsigned long addr; + struct vm_struct *area; + + /* + * Page align the mapping address and size, taking account of any + * offset. + */ + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(size + offset); + + /* + * Don't allow wraparound, zero size or outside PHYS_MASK. + */ + last_addr = phys_addr + size - 1; + if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK)) + return NULL; + + /* + * Don't allow RAM to be mapped. + */ + if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr)))) + return NULL; + + area = get_vm_area_caller(size, VM_IOREMAP, caller); + if (!area) + return NULL; + addr = (unsigned long)area->addr; + area->phys_addr = phys_addr; + + err = ioremap_page_range(addr, addr + size, phys_addr, prot); + if (err) { + vunmap((void *)addr); + return NULL; + } + + return (void __iomem *)(offset + addr); +} + +void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot) +{ + return __ioremap_caller(phys_addr, size, prot, + __builtin_return_address(0)); +} +EXPORT_SYMBOL(__ioremap); + +void __iounmap(volatile void __iomem *io_addr) +{ + unsigned long addr = (unsigned long)io_addr & PAGE_MASK; + + /* + * We could get an address outside vmalloc range in case + * of ioremap_cache() reusing a RAM mapping. + */ + if (VMALLOC_START <= addr && addr < VMALLOC_END) + vunmap((void *)addr); +} +EXPORT_SYMBOL(__iounmap); + +void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size) +{ + /* For normal memory we already have a cacheable mapping. */ + if (pfn_valid(__phys_to_pfn(phys_addr))) + return (void __iomem *)__phys_to_virt(phys_addr); + + return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL), + __builtin_return_address(0)); +} +EXPORT_SYMBOL(ioremap_cache); + +/* + * Must be called after early_fixmap_init + */ +void __init early_ioremap_init(void) +{ + early_ioremap_setup(); +} |