[mirror_ubuntu-artful-kernel.git] / drivers / mtd / maps / ixp4xx.c

/*
 * drivers/mtd/maps/ixp4xx.c
 *
 * MTD Map file for IXP4XX based systems. Please do not make per-board
 * changes in here. If your board needs special setup, do it in your
 * platform level code in arch/arm/mach-ixp4xx/board-setup.c
 *
 * Original Author: Intel Corporation
 * Maintainer: Deepak Saxena <dsaxena@mvista.com>
 *
 * Copyright (C) 2002 Intel Corporation
 * Copyright (C) 2003-2004 MontaVista Software, Inc.
 *
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/platform_device.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>

#include <asm/io.h>
#include <asm/mach/flash.h>

#include <linux/reboot.h>

/*
 * Read/write a 16 bit word from flash address 'addr'.
 *
 * When the cpu is in little-endian mode it swizzles the address lines
 * ('address coherency') so we need to undo the swizzling to ensure commands
 * and the like end up on the correct flash address.
 *
 * To further complicate matters, due to the way the expansion bus controller
 * handles 32 bit reads, the byte stream ABCD is stored on the flash as:
 *     D15    D0
 *     +---+---+
 *     | A | B | 0
 *     +---+---+
 *     | C | D | 2
 *     +---+---+
 * This means that on LE systems each 16 bit word must be swapped. Note that
 * this requires CONFIG_MTD_CFI_BE_BYTE_SWAP to be enabled to 'unswap' the CFI
 * data and other flash commands which are always in D7-D0.
 */
#ifndef __ARMEB__
#ifndef CONFIG_MTD_CFI_BE_BYTE_SWAP
#  error CONFIG_MTD_CFI_BE_BYTE_SWAP required
#endif

static inline u16 flash_read16(void __iomem *addr)
{
	return be16_to_cpu(__raw_readw((void __iomem *)((unsigned long)addr ^ 0x2)));
}

static inline void flash_write16(u16 d, void __iomem *addr)
{
	__raw_writew(cpu_to_be16(d), (void __iomem *)((unsigned long)addr ^ 0x2));
}

#define	BYTE0(h)	((h) & 0xFF)
#define	BYTE1(h)	(((h) >> 8) & 0xFF)

#else

static inline u16 flash_read16(const void __iomem *addr)
{
	return __raw_readw(addr);
}

static inline void flash_write16(u16 d, void __iomem *addr)
{
	__raw_writew(d, addr);
}

#define	BYTE0(h)	(((h) >> 8) & 0xFF)
#define	BYTE1(h)	((h) & 0xFF)
#endif

static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs)
{
	map_word val;
	val.x[0] = flash_read16(map->virt + ofs);
	return val;
}

/*
 * The IXP4xx expansion bus only allows 16-bit wide acceses
 * when attached to a 16-bit wide device (such as the 28F128J3A),
 * so we can't just memcpy_fromio().
 */
static void ixp4xx_copy_from(struct map_info *map, void *to,
			     unsigned long from, ssize_t len)
{
	u8 *dest = (u8 *) to;
	void __iomem *src = map->virt + from;

	if (len <= 0)
		return;

	if (from & 1) {
		*dest++ = BYTE1(flash_read16(src));
                src++;
		--len;
	}

	while (len >= 2) {
		u16 data = flash_read16(src);
		*dest++ = BYTE0(data);
		*dest++ = BYTE1(data);
		src += 2;
		len -= 2;
        }

	if (len > 0)
		*dest++ = BYTE0(flash_read16(src));
}

/*
 * Unaligned writes are ignored, causing the 8-bit
 * probe to fail and proceed to the 16-bit probe (which succeeds).
 */
static void ixp4xx_probe_write16(struct map_info *map, map_word d, unsigned long adr)
{
	if (!(adr & 1))
		flash_write16(d.x[0], map->virt + adr);
}

/*
 * Fast write16 function without the probing check above
 */
static void ixp4xx_write16(struct map_info *map, map_word d, unsigned long adr)
{
	flash_write16(d.x[0], map->virt + adr);
}

struct ixp4xx_flash_info {
	struct mtd_info *mtd;
	struct map_info map;
	struct mtd_partition *partitions;
	struct resource *res;
};

static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };

static int ixp4xx_flash_remove(struct platform_device *dev)
{
	struct flash_platform_data *plat = dev->dev.platform_data;
	struct ixp4xx_flash_info *info = platform_get_drvdata(dev);

	platform_set_drvdata(dev, NULL);

	if(!info)
		return 0;

	if (info->mtd) {
		del_mtd_partitions(info->mtd);
		map_destroy(info->mtd);
	}
	if (info->map.virt)
		iounmap(info->map.virt);

	kfree(info->partitions);

	if (info->res) {
		release_resource(info->res);
		kfree(info->res);
	}

	if (plat->exit)
		plat->exit();

	return 0;
}

static int ixp4xx_flash_probe(struct platform_device *dev)
{
	struct flash_platform_data *plat = dev->dev.platform_data;
	struct ixp4xx_flash_info *info;
	int err = -1;

	if (!plat)
		return -ENODEV;

	if (plat->init) {
		err = plat->init();
		if (err)
			return err;
	}

	info = kmalloc(sizeof(struct ixp4xx_flash_info), GFP_KERNEL);
	if(!info) {
		err = -ENOMEM;
		goto Error;
	}
	memzero(info, sizeof(struct ixp4xx_flash_info));

	platform_set_drvdata(dev, info);

	/*
	 * Tell the MTD layer we're not 1:1 mapped so that it does
	 * not attempt to do a direct access on us.
	 */
	info->map.phys = NO_XIP;
	info->map.size = dev->resource->end - dev->resource->start + 1;

	/*
	 * We only support 16-bit accesses for now. If and when
	 * any board use 8-bit access, we'll fixup the driver to
	 * handle that.
	 */
	info->map.bankwidth = 2;
	info->map.name = dev->dev.bus_id;
	info->map.read = ixp4xx_read16,
	info->map.write = ixp4xx_probe_write16,
	info->map.copy_from = ixp4xx_copy_from,

	info->res = request_mem_region(dev->resource->start,
			dev->resource->end - dev->resource->start + 1,
			"IXP4XXFlash");
	if (!info->res) {
		printk(KERN_ERR "IXP4XXFlash: Could not reserve memory region\n");
		err = -ENOMEM;
		goto Error;
	}

	info->map.virt = ioremap(dev->resource->start,
				 dev->resource->end - dev->resource->start + 1);
	if (!info->map.virt) {
		printk(KERN_ERR "IXP4XXFlash: Failed to ioremap region\n");
		err = -EIO;
		goto Error;
	}

	info->mtd = do_map_probe(plat->map_name, &info->map);
	if (!info->mtd) {
		printk(KERN_ERR "IXP4XXFlash: map_probe failed\n");
		err = -ENXIO;
		goto Error;
	}
	info->mtd->owner = THIS_MODULE;

	/* Use the fast version */
	info->map.write = ixp4xx_write16,

	err = parse_mtd_partitions(info->mtd, probes, &info->partitions, dev->resource->start);
	if (err > 0) {
		err = add_mtd_partitions(info->mtd, info->partitions, err);
		if(err)
			printk(KERN_ERR "Could not parse partitions\n");
	}

	if (err)
		goto Error;

	return 0;

Error:
	ixp4xx_flash_remove(dev);
	return err;
}

static struct platform_driver ixp4xx_flash_driver = {
	.probe		= ixp4xx_flash_probe,
	.remove		= ixp4xx_flash_remove,
	.driver		= {
		.name	= "IXP4XX-Flash",
		.owner	= THIS_MODULE,
	},
};

static int __init ixp4xx_flash_init(void)
{
	return platform_driver_register(&ixp4xx_flash_driver);
}

static void __exit ixp4xx_flash_exit(void)
{
	platform_driver_unregister(&ixp4xx_flash_driver);
}


module_init(ixp4xx_flash_init);
module_exit(ixp4xx_flash_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems");
MODULE_AUTHOR("Deepak Saxena");
MODULE_ALIAS("platform:IXP4XX-Flash");
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* drivers/mtd/maps/ixp4xx.c
	3	*
	4	* MTD Map file for IXP4XX based systems. Please do not make per-board
	5	* changes in here. If your board needs special setup, do it in your
	6	* platform level code in arch/arm/mach-ixp4xx/board-setup.c
	7	*
	8	* Original Author: Intel Corporation
	9	* Maintainer: Deepak Saxena <dsaxena@mvista.com>
	10	*
	11	* Copyright (C) 2002 Intel Corporation
	12	* Copyright (C) 2003-2004 MontaVista Software, Inc.
	13	*
	14	*/
	15
	16	#include <linux/module.h>
	17	#include <linux/types.h>
	18	#include <linux/init.h>
	19	#include <linux/kernel.h>
	20	#include <linux/string.h>
4e57b681 TS	21	#include <linux/slab.h>
	22	#include <linux/ioport.h>
	23	#include <linux/device.h>
4fd5f826	24	#include <linux/platform_device.h>
4e57b681	25
1da177e4 LT	26	#include <linux/mtd/mtd.h>
	27	#include <linux/mtd/map.h>
	28	#include <linux/mtd/partitions.h>
4e57b681	29
1da177e4	30	#include <asm/io.h>
1da177e4 LT	31	#include <asm/mach/flash.h>
	32
	33	#include <linux/reboot.h>
	34
3c773547 JB	35	/*
	36	* Read/write a 16 bit word from flash address 'addr'.
	37	*
	38	* When the cpu is in little-endian mode it swizzles the address lines
	39	* ('address coherency') so we need to undo the swizzling to ensure commands
	40	* and the like end up on the correct flash address.
	41	*
	42	* To further complicate matters, due to the way the expansion bus controller
	43	* handles 32 bit reads, the byte stream ABCD is stored on the flash as:
	44	* D15 D0
	45	* +---+---+
	46	* \| A \| B \| 0
	47	* +---+---+
	48	* \| C \| D \| 2
	49	* +---+---+
	50	* This means that on LE systems each 16 bit word must be swapped. Note that
	51	* this requires CONFIG_MTD_CFI_BE_BYTE_SWAP to be enabled to 'unswap' the CFI
	52	* data and other flash commands which are always in D7-D0.
	53	*/
1da177e4	54	#ifndef __ARMEB__
3c773547 JB	55	#ifndef CONFIG_MTD_CFI_BE_BYTE_SWAP
	56	# error CONFIG_MTD_CFI_BE_BYTE_SWAP required
	57	#endif
	58
	59	static inline u16 flash_read16(void __iomem *addr)
	60	{
	61	return be16_to_cpu(__raw_readw((void __iomem *)((unsigned long)addr ^ 0x2)));
	62	}
	63
	64	static inline void flash_write16(u16 d, void __iomem *addr)
	65	{
	66	__raw_writew(cpu_to_be16(d), (void __iomem *)((unsigned long)addr ^ 0x2));
	67	}
	68
1da177e4 LT	69	#define BYTE0(h) ((h) & 0xFF)
1da177e4 LT	70	#define BYTE1(h) (((h) >> 8) & 0xFF)
3c773547	71
1da177e4	72	#else
3c773547 JB	73
	74	static inline u16 flash_read16(const void __iomem *addr)
	75	{
	76	return __raw_readw(addr);
	77	}
	78
	79	static inline void flash_write16(u16 d, void __iomem *addr)
	80	{
	81	__raw_writew(d, addr);
	82	}
	83
1da177e4 LT	84	#define BYTE0(h) (((h) >> 8) & 0xFF)
	85	#define BYTE1(h) ((h) & 0xFF)
	86	#endif
	87
	88	static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs)
	89	{
	90	map_word val;
3c773547	91	val.x[0] = flash_read16(map->virt + ofs);
1da177e4 LT	92	return val;
	93	}
	94
	95	/*
	96	* The IXP4xx expansion bus only allows 16-bit wide acceses
	97	* when attached to a 16-bit wide device (such as the 28F128J3A),
	98	* so we can't just memcpy_fromio().
	99	*/
	100	static void ixp4xx_copy_from(struct map_info map, void to,
	101	unsigned long from, ssize_t len)
	102	{
1da177e4	103	u8 dest = (u8 ) to;
9090ed0b	104	void __iomem *src = map->virt + from;
1da177e4	105
3c773547 JB	106	if (len <= 0)
	107	return;
	108
	109	if (from & 1) {
	110	*dest++ = BYTE1(flash_read16(src));
	111	src++;
	112	--len;
1da177e4 LT	113	}
1da177e4 LT	114
3c773547 JB	115	while (len >= 2) {
	116	u16 data = flash_read16(src);
	117	*dest++ = BYTE0(data);
	118	*dest++ = BYTE1(data);
	119	src += 2;
	120	len -= 2;
	121	}
	122
	123	if (len > 0)
	124	*dest++ = BYTE0(flash_read16(src));
1da177e4 LT	125	}
1da177e4 LT	126
69f34c98	127	/*
1da177e4 LT	128	* Unaligned writes are ignored, causing the 8-bit
	129	* probe to fail and proceed to the 16-bit probe (which succeeds).
	130	*/
	131	static void ixp4xx_probe_write16(struct map_info *map, map_word d, unsigned long adr)
	132	{
	133	if (!(adr & 1))
3c773547	134	flash_write16(d.x[0], map->virt + adr);
1da177e4 LT	135	}
1da177e4 LT	136
69f34c98	137	/*
1da177e4 LT	138	* Fast write16 function without the probing check above
	139	*/
	140	static void ixp4xx_write16(struct map_info *map, map_word d, unsigned long adr)
	141	{
3c773547	142	flash_write16(d.x[0], map->virt + adr);
1da177e4 LT	143	}
	144
	145	struct ixp4xx_flash_info {
	146	struct mtd_info *mtd;
	147	struct map_info map;
	148	struct mtd_partition *partitions;
	149	struct resource *res;
	150	};
	151
	152	static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
	153
3ae5eaec	154	static int ixp4xx_flash_remove(struct platform_device *dev)
1da177e4	155	{
1da177e4	156	struct flash_platform_data *plat = dev->dev.platform_data;
3ae5eaec	157	struct ixp4xx_flash_info *info = platform_get_drvdata(dev);
1da177e4	158
3ae5eaec	159	platform_set_drvdata(dev, NULL);
1da177e4 LT	160
	161	if(!info)
	162	return 0;
	163
1da177e4 LT	164	if (info->mtd) {
	165	del_mtd_partitions(info->mtd);
	166	map_destroy(info->mtd);
	167	}
9090ed0b DV	168	if (info->map.virt)
9090ed0b DV	169	iounmap(info->map.virt);
1da177e4	170
fa671646	171	kfree(info->partitions);
1da177e4 LT	172
	173	if (info->res) {
	174	release_resource(info->res);
	175	kfree(info->res);
	176	}
	177
	178	if (plat->exit)
	179	plat->exit();
	180
1da177e4 LT	181	return 0;
	182	}
	183
3ae5eaec	184	static int ixp4xx_flash_probe(struct platform_device *dev)
1da177e4	185	{
1da177e4 LT	186	struct flash_platform_data *plat = dev->dev.platform_data;
	187	struct ixp4xx_flash_info *info;
	188	int err = -1;
	189
	190	if (!plat)
	191	return -ENODEV;
	192
	193	if (plat->init) {
	194	err = plat->init();
	195	if (err)
	196	return err;
	197	}
	198
	199	info = kmalloc(sizeof(struct ixp4xx_flash_info), GFP_KERNEL);
	200	if(!info) {
	201	err = -ENOMEM;
	202	goto Error;
69f34c98	203	}
1da177e4 LT	204	memzero(info, sizeof(struct ixp4xx_flash_info));
1da177e4 LT	205
3ae5eaec	206	platform_set_drvdata(dev, info);
1da177e4	207
1da177e4 LT	208	/*
	209	* Tell the MTD layer we're not 1:1 mapped so that it does
	210	* not attempt to do a direct access on us.
	211	*/
	212	info->map.phys = NO_XIP;
	213	info->map.size = dev->resource->end - dev->resource->start + 1;
	214
	215	/*
	216	* We only support 16-bit accesses for now. If and when
	217	* any board use 8-bit access, we'll fixup the driver to
	218	* handle that.
	219	*/
	220	info->map.bankwidth = 2;
	221	info->map.name = dev->dev.bus_id;
	222	info->map.read = ixp4xx_read16,
	223	info->map.write = ixp4xx_probe_write16,
	224	info->map.copy_from = ixp4xx_copy_from,
	225
69f34c98 TG	226	info->res = request_mem_region(dev->resource->start,
69f34c98 TG	227	dev->resource->end - dev->resource->start + 1,
1da177e4 LT	228	"IXP4XXFlash");
	229	if (!info->res) {
	230	printk(KERN_ERR "IXP4XXFlash: Could not reserve memory region\n");
	231	err = -ENOMEM;
	232	goto Error;
	233	}
	234
9090ed0b DV	235	info->map.virt = ioremap(dev->resource->start,
	236	dev->resource->end - dev->resource->start + 1);
	237	if (!info->map.virt) {
1da177e4 LT	238	printk(KERN_ERR "IXP4XXFlash: Failed to ioremap region\n");
	239	err = -EIO;
	240	goto Error;
	241	}
	242
	243	info->mtd = do_map_probe(plat->map_name, &info->map);
	244	if (!info->mtd) {
	245	printk(KERN_ERR "IXP4XXFlash: map_probe failed\n");
	246	err = -ENXIO;
	247	goto Error;
	248	}
	249	info->mtd->owner = THIS_MODULE;
69f34c98	250
1da177e4 LT	251	/* Use the fast version */
	252	info->map.write = ixp4xx_write16,
	253
f40a6f1c	254	err = parse_mtd_partitions(info->mtd, probes, &info->partitions, dev->resource->start);
1da177e4 LT	255	if (err > 0) {
	256	err = add_mtd_partitions(info->mtd, info->partitions, err);
	257	if(err)
	258	printk(KERN_ERR "Could not parse partitions\n");
	259	}
	260
	261	if (err)
	262	goto Error;
	263
	264	return 0;
	265
	266	Error:
3ae5eaec	267	ixp4xx_flash_remove(dev);
1da177e4 LT	268	return err;
	269	}
	270
3ae5eaec	271	static struct platform_driver ixp4xx_flash_driver = {
1da177e4 LT	272	.probe = ixp4xx_flash_probe,
1da177e4 LT	273	.remove = ixp4xx_flash_remove,
3ae5eaec RK	274	.driver = {
3ae5eaec RK	275	.name = "IXP4XX-Flash",
41d867c9	276	.owner = THIS_MODULE,
3ae5eaec	277	},
1da177e4 LT	278	};
	279
	280	static int __init ixp4xx_flash_init(void)
	281	{
3ae5eaec	282	return platform_driver_register(&ixp4xx_flash_driver);
1da177e4 LT	283	}
	284
	285	static void __exit ixp4xx_flash_exit(void)
	286	{
3ae5eaec	287	platform_driver_unregister(&ixp4xx_flash_driver);
1da177e4 LT	288	}
	289
	290
	291	module_init(ixp4xx_flash_init);
	292	module_exit(ixp4xx_flash_exit);
	293
	294	MODULE_LICENSE("GPL");
82810a90	295	MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems");
1da177e4	296	MODULE_AUTHOR("Deepak Saxena");
41d867c9	297	MODULE_ALIAS("platform:IXP4XX-Flash");