[linux-2.6-block.git] / arch / arm64 / mm / ioremap.c

/*
 * 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>

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;

	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);
Commit	Line	Data
fc47897d CM	1	/*
	2	* Based on arch/arm/mm/ioremap.c
	3	*
	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
	7	* by Russell King
	8	* Copyright (C) 2012 ARM Ltd.
	9	*
	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.
	13	*
	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.
	18	*
	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/>.
	21	*/
	22
	23	#include <linux/export.h>
	24	#include <linux/mm.h>
	25	#include <linux/vmalloc.h>
	26	#include <linux/io.h>
	27
	28	static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size,
	29	pgprot_t prot, void *caller)
	30	{
	31	unsigned long last_addr;
	32	unsigned long offset = phys_addr & ~PAGE_MASK;
	33	int err;
	34	unsigned long addr;
	35	struct vm_struct *area;
	36
	37	/*
	38	* Page align the mapping address and size, taking account of any
	39	* offset.
	40	*/
	41	phys_addr &= PAGE_MASK;
	42	size = PAGE_ALIGN(size + offset);
	43
	44	/*
	45	* Don't allow wraparound, zero size or outside PHYS_MASK.
	46	*/
	47	last_addr = phys_addr + size - 1;
	48	if (!size \|\| last_addr < phys_addr \|\| (last_addr & ~PHYS_MASK))
	49	return NULL;
	50
	51	/*
	52	* Don't allow RAM to be mapped.
	53	*/
	54	if (WARN_ON(pfn_valid(__phys_to_pfn(phys_addr))))
	55	return NULL;
	56
	57	area = get_vm_area_caller(size, VM_IOREMAP, caller);
	58	if (!area)
	59	return NULL;
	60	addr = (unsigned long)area->addr;
	61
	62	err = ioremap_page_range(addr, addr + size, phys_addr, prot);
	63	if (err) {
	64	vunmap((void *)addr);
65	return NULL;
66	}
67
68	return (void __iomem *)(offset + addr);
69	}
70
71	void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot)
72	{
73	return __ioremap_caller(phys_addr, size, prot,
74	__builtin_return_address(0));
75	}
76	EXPORT_SYMBOL(__ioremap);
77
78	void __iounmap(volatile void __iomem *io_addr)
79	{
c04e8e2f	80	unsigned long addr = (unsigned long)io_addr & PAGE_MASK;
fc47897d	81
c04e8e2f MS	82	/*
	83	* We could get an address outside vmalloc range in case
	84	* of ioremap_cache() reusing a RAM mapping.
	85	*/
	86	if (VMALLOC_START <= addr && addr < VMALLOC_END)
	87	vunmap((void *)addr);
fc47897d CM	88	}
fc47897d CM	89	EXPORT_SYMBOL(__iounmap);
c04e8e2f MS	90
	91	void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size)
	92	{
	93	/* For normal memory we already have a cacheable mapping. */
	94	if (pfn_valid(__phys_to_pfn(phys_addr)))
	95	return (void __iomem *)__phys_to_virt(phys_addr);
	96
	97	return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL),
	98	__builtin_return_address(0));
	99	}
	100	EXPORT_SYMBOL(ioremap_cache);