1/*
  2 * drivers/mtd/nand/orion_nand.c
  3 *
  4 * NAND support for Marvell Orion SoC platforms
  5 *
  6 * Tzachi Perelstein <tzachi@marvell.com>
  7 *
  8 * This file is licensed under  the terms of the GNU General Public
  9 * License version 2. This program is licensed "as is" without any
 10 * warranty of any kind, whether express or implied.
 11 */
 12
 13#include <linux/slab.h>
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/mtd/mtd.h>
 17#include <linux/mtd/nand.h>
 18#include <linux/mtd/partitions.h>
 19#include <asm/io.h>
 20#include <asm/sizes.h>
 21#include <mach/hardware.h>
 22#include <plat/orion_nand.h>
 23
 24static const char *part_probes[] = { "cmdlinepart", NULL };
 25
 26static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 27{
 28	struct nand_chip *nc = mtd->priv;
 29	struct orion_nand_data *board = nc->priv;
 30	u32 offs;
 31
 32	if (cmd == NAND_CMD_NONE)
 33		return;
 34
 35	if (ctrl & NAND_CLE)
 36		offs = (1 << board->cle);
 37	else if (ctrl & NAND_ALE)
 38		offs = (1 << board->ale);
 39	else
 40		return;
 41
 42	if (nc->options & NAND_BUSWIDTH_16)
 43		offs <<= 1;
 44
 45	writeb(cmd, nc->IO_ADDR_W + offs);
 46}
 47
 48static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 49{
 50	struct nand_chip *chip = mtd->priv;
 51	void __iomem *io_base = chip->IO_ADDR_R;
 52	uint64_t *buf64;
 53	int i = 0;
 54
 55	while (len && (unsigned long)buf & 7) {
 56		*buf++ = readb(io_base);
 57		len--;
 58	}
 59	buf64 = (uint64_t *)buf;
 60	while (i < len/8) {
 61		/*
 62		 * Since GCC has no proper constraint (PR 43518)
 63		 * force x variable to r2/r3 registers as ldrd instruction
 64		 * requires first register to be even.
 65		 */
 66		register uint64_t x asm ("r2");
 67
 68		asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
 69		buf64[i++] = x;
 70	}
 71	i *= 8;
 72	while (i < len)
 73		buf[i++] = readb(io_base);
 74}
 75
 76static int __init orion_nand_probe(struct platform_device *pdev)
 77{
 78	struct mtd_info *mtd;
 79	struct nand_chip *nc;
 80	struct orion_nand_data *board;
 81	struct resource *res;
 82	void __iomem *io_base;
 83	int ret = 0;
 84	struct mtd_partition *partitions = NULL;
 85	int num_part = 0;
 86
 87	nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
 88	if (!nc) {
 89		printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
 90		ret = -ENOMEM;
 91		goto no_res;
 92	}
 93	mtd = (struct mtd_info *)(nc + 1);
 94
 95	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 96	if (!res) {
 97		ret = -ENODEV;
 98		goto no_res;
 99	}
100
101	io_base = ioremap(res->start, resource_size(res));
102	if (!io_base) {
103		printk(KERN_ERR "orion_nand: ioremap failed\n");
104		ret = -EIO;
105		goto no_res;
106	}
107
108	board = pdev->dev.platform_data;
109
110	mtd->priv = nc;
111	mtd->owner = THIS_MODULE;
112
113	nc->priv = board;
114	nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
115	nc->cmd_ctrl = orion_nand_cmd_ctrl;
116	nc->read_buf = orion_nand_read_buf;
117	nc->ecc.mode = NAND_ECC_SOFT;
118
119	if (board->chip_delay)
120		nc->chip_delay = board->chip_delay;
121
122	if (board->width == 16)
123		nc->options |= NAND_BUSWIDTH_16;
124
125	if (board->dev_ready)
126		nc->dev_ready = board->dev_ready;
127
128	platform_set_drvdata(pdev, mtd);
129
130	if (nand_scan(mtd, 1)) {
131		ret = -ENXIO;
132		goto no_dev;
133	}
134
135#ifdef CONFIG_MTD_CMDLINE_PARTS
136	mtd->name = "orion_nand";
137	num_part = parse_mtd_partitions(mtd, part_probes, &partitions, 0);
138#endif
139	/* If cmdline partitions have been passed, let them be used */
140	if (num_part <= 0) {
141		num_part = board->nr_parts;
142		partitions = board->parts;
143	}
144
145	ret = mtd_device_register(mtd, partitions, num_part);
146	if (ret) {
147		nand_release(mtd);
148		goto no_dev;
149	}
150
151	return 0;
152
153no_dev:
154	platform_set_drvdata(pdev, NULL);
155	iounmap(io_base);
156no_res:
157	kfree(nc);
158
159	return ret;
160}
161
162static int __devexit orion_nand_remove(struct platform_device *pdev)
163{
164	struct mtd_info *mtd = platform_get_drvdata(pdev);
165	struct nand_chip *nc = mtd->priv;
166
167	nand_release(mtd);
168
169	iounmap(nc->IO_ADDR_W);
170
171	kfree(nc);
172
173	return 0;
174}
175
176static struct platform_driver orion_nand_driver = {
177	.remove		= __devexit_p(orion_nand_remove),
178	.driver		= {
179		.name	= "orion_nand",
180		.owner	= THIS_MODULE,
181	},
182};
183
184static int __init orion_nand_init(void)
185{
186	return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
187}
188
189static void __exit orion_nand_exit(void)
190{
191	platform_driver_unregister(&orion_nand_driver);
192}
193
194module_init(orion_nand_init);
195module_exit(orion_nand_exit);
196
197MODULE_LICENSE("GPL");
198MODULE_AUTHOR("Tzachi Perelstein");
199MODULE_DESCRIPTION("NAND glue for Orion platforms");
200MODULE_ALIAS("platform:orion_nand");