[people/arne_f/kernel.git] / arch / sh / mm / ioremap_fixed.c

/*
 * Re-map IO memory to kernel address space so that we can access it.
 *
 * These functions should only be used when it is necessary to map a
 * physical address space into the kernel address space before ioremap()
 * can be used, e.g. early in boot before paging_init().
 *
 * Copyright (C) 2009  Matt Fleming
 */

#include <linux/vmalloc.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/bootmem.h>
#include <linux/proc_fs.h>
#include <asm/fixmap.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/addrspace.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>

struct ioremap_map {
	void __iomem *addr;
	unsigned long size;
	unsigned long fixmap_addr;
};

static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS];

void __init ioremap_fixed_init(void)
{
	struct ioremap_map *map;
	int i;

	for (i = 0; i < FIX_N_IOREMAPS; i++) {
		map = &ioremap_maps[i];
		map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i);
	}
}

void __init __iomem *
ioremap_fixed(phys_addr_t phys_addr, unsigned long size, pgprot_t prot)
{
	enum fixed_addresses idx0, idx;
	struct ioremap_map *map;
	unsigned int nrpages;
	unsigned long offset;
	int i, slot;

	/*
	 * Mappings have to be page-aligned
	 */
	offset = phys_addr & ~PAGE_MASK;
	phys_addr &= PAGE_MASK;
	size = PAGE_ALIGN(phys_addr + size) - phys_addr;

	slot = -1;
	for (i = 0; i < FIX_N_IOREMAPS; i++) {
		map = &ioremap_maps[i];
		if (!map->addr) {
			map->size = size;
			slot = i;
			break;
		}
	}

	if (slot < 0)
		return NULL;

	/*
	 * Mappings have to fit in the FIX_IOREMAP area.
	 */
	nrpages = size >> PAGE_SHIFT;
	if (nrpages > FIX_N_IOREMAPS)
		return NULL;

	/*
	 * Ok, go for it..
	 */
	idx0 = FIX_IOREMAP_BEGIN + slot;
	idx = idx0;
	while (nrpages > 0) {
		pgprot_val(prot) |= _PAGE_WIRED;
		__set_fixmap(idx, phys_addr, prot);
		phys_addr += PAGE_SIZE;
		idx++;
		--nrpages;
	}

	map->addr = (void __iomem *)(offset + map->fixmap_addr);
	return map->addr;
}

int iounmap_fixed(void __iomem *addr)
{
	enum fixed_addresses idx;
	struct ioremap_map *map;
	unsigned int nrpages;
	int i, slot;

	slot = -1;
	for (i = 0; i < FIX_N_IOREMAPS; i++) {
		map = &ioremap_maps[i];
		if (map->addr == addr) {
			slot = i;
			break;
		}
	}

	/*
	 * If we don't match, it's not for us.
	 */
	if (slot < 0)
		return -EINVAL;

	nrpages = map->size >> PAGE_SHIFT;

	idx = FIX_IOREMAP_BEGIN + slot + nrpages - 1;
	while (nrpages > 0) {
		__clear_fixmap(idx, __pgprot(_PAGE_WIRED));
		--idx;
		--nrpages;
	}

	map->size = 0;
	map->addr = NULL;

	return 0;
}
Commit	Line	Data
4d35b93a MF	1	/*
	2	* Re-map IO memory to kernel address space so that we can access it.
	3	*
	4	* These functions should only be used when it is necessary to map a
	5	* physical address space into the kernel address space before ioremap()
	6	* can be used, e.g. early in boot before paging_init().
	7	*
	8	* Copyright (C) 2009 Matt Fleming
	9	*/
	10
	11	#include <linux/vmalloc.h>
	12	#include <linux/ioport.h>
	13	#include <linux/module.h>
	14	#include <linux/mm.h>
	15	#include <linux/io.h>
	16	#include <linux/bootmem.h>
	17	#include <linux/proc_fs.h>
4d35b93a MF	18	#include <asm/fixmap.h>
	19	#include <asm/page.h>
	20	#include <asm/pgalloc.h>
	21	#include <asm/addrspace.h>
	22	#include <asm/cacheflush.h>
	23	#include <asm/tlbflush.h>
	24	#include <asm/mmu.h>
	25	#include <asm/mmu_context.h>
	26
	27	struct ioremap_map {
	28	void __iomem *addr;
	29	unsigned long size;
	30	unsigned long fixmap_addr;
	31	};
	32
	33	static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS];
	34
	35	void __init ioremap_fixed_init(void)
	36	{
	37	struct ioremap_map *map;
	38	int i;
	39
	40	for (i = 0; i < FIX_N_IOREMAPS; i++) {
	41	map = &ioremap_maps[i];
	42	map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i);
	43	}
	44	}
	45
	46	void __init __iomem *
90e7d649	47	ioremap_fixed(phys_addr_t phys_addr, unsigned long size, pgprot_t prot)
4d35b93a MF	48	{
4d35b93a MF	49	enum fixed_addresses idx0, idx;
4d35b93a	50	struct ioremap_map *map;
4d35b93a	51	unsigned int nrpages;
90e7d649	52	unsigned long offset;
4d35b93a MF	53	int i, slot;
4d35b93a MF	54
90e7d649 PM	55	/*
	56	* Mappings have to be page-aligned
	57	*/
	58	offset = phys_addr & ~PAGE_MASK;
	59	phys_addr &= PAGE_MASK;
	60	size = PAGE_ALIGN(phys_addr + size) - phys_addr;
	61
4d35b93a MF	62	slot = -1;
	63	for (i = 0; i < FIX_N_IOREMAPS; i++) {
	64	map = &ioremap_maps[i];
	65	if (!map->addr) {
	66	map->size = size;
	67	slot = i;
	68	break;
	69	}
	70	}
	71
	72	if (slot < 0)
	73	return NULL;
	74
4d35b93a MF	75	/*
	76	* Mappings have to fit in the FIX_IOREMAP area.
	77	*/
	78	nrpages = size >> PAGE_SHIFT;
	79	if (nrpages > FIX_N_IOREMAPS)
	80	return NULL;
	81
	82	/*
	83	* Ok, go for it..
	84	*/
	85	idx0 = FIX_IOREMAP_BEGIN + slot;
	86	idx = idx0;
	87	while (nrpages > 0) {
	88	pgprot_val(prot) \|= _PAGE_WIRED;
	89	__set_fixmap(idx, phys_addr, prot);
	90	phys_addr += PAGE_SIZE;
	91	idx++;
	92	--nrpages;
	93	}
	94
	95	map->addr = (void __iomem *)(offset + map->fixmap_addr);
	96	return map->addr;
	97	}
	98
4f744aff	99	int iounmap_fixed(void __iomem *addr)
4d35b93a MF	100	{
4d35b93a MF	101	enum fixed_addresses idx;
4d35b93a	102	struct ioremap_map *map;
4d35b93a MF	103	unsigned int nrpages;
4d35b93a MF	104	int i, slot;
4d35b93a MF	105
	106	slot = -1;
	107	for (i = 0; i < FIX_N_IOREMAPS; i++) {
	108	map = &ioremap_maps[i];
	109	if (map->addr == addr) {
	110	slot = i;
	111	break;
	112	}
	113	}
	114
4f744aff PM	115	/*
	116	* If we don't match, it's not for us.
	117	*/
4d35b93a	118	if (slot < 0)
4f744aff	119	return -EINVAL;
4d35b93a	120
920efaab	121	nrpages = map->size >> PAGE_SHIFT;
4d35b93a	122
920efaab	123	idx = FIX_IOREMAP_BEGIN + slot + nrpages - 1;
4d35b93a	124	while (nrpages > 0) {
acf2c968	125	__clear_fixmap(idx, __pgprot(_PAGE_WIRED));
4d35b93a MF	126	--idx;
	127	--nrpages;
	128	}
	129
	130	map->size = 0;
	131	map->addr = NULL;
4f744aff PM	132
4f744aff PM	133	return 0;
4d35b93a	134	}