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 
24 #ifdef CONFIG_MTD_CMDLINE_PARTS
25 static const char *part_probes[] = { "cmdlinepart", NULL };
26 #endif
27 
orion_nand_cmd_ctrl(struct mtd_info * mtd,int cmd,unsigned int ctrl)28 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
29 {
30 	struct nand_chip *nc = mtd->priv;
31 	struct orion_nand_data *board = nc->priv;
32 	u32 offs;
33 
34 	if (cmd == NAND_CMD_NONE)
35 		return;
36 
37 	if (ctrl & NAND_CLE)
38 		offs = (1 << board->cle);
39 	else if (ctrl & NAND_ALE)
40 		offs = (1 << board->ale);
41 	else
42 		return;
43 
44 	if (nc->options & NAND_BUSWIDTH_16)
45 		offs <<= 1;
46 
47 	writeb(cmd, nc->IO_ADDR_W + offs);
48 }
49 
orion_nand_read_buf(struct mtd_info * mtd,uint8_t * buf,int len)50 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
51 {
52 	struct nand_chip *chip = mtd->priv;
53 	void __iomem *io_base = chip->IO_ADDR_R;
54 	uint64_t *buf64;
55 	int i = 0;
56 
57 	while (len && (unsigned long)buf & 7) {
58 		*buf++ = readb(io_base);
59 		len--;
60 	}
61 	buf64 = (uint64_t *)buf;
62 	while (i < len/8) {
63 		/*
64 		 * Since GCC has no proper constraint (PR 43518)
65 		 * force x variable to r2/r3 registers as ldrd instruction
66 		 * requires first register to be even.
67 		 */
68 		register uint64_t x asm ("r2");
69 
70 		asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
71 		buf64[i++] = x;
72 	}
73 	i *= 8;
74 	while (i < len)
75 		buf[i++] = readb(io_base);
76 }
77 
orion_nand_probe(struct platform_device * pdev)78 static int __init orion_nand_probe(struct platform_device *pdev)
79 {
80 	struct mtd_info *mtd;
81 	struct nand_chip *nc;
82 	struct orion_nand_data *board;
83 	struct resource *res;
84 	void __iomem *io_base;
85 	int ret = 0;
86 #ifdef CONFIG_MTD_PARTITIONS
87 	struct mtd_partition *partitions = NULL;
88 	int num_part = 0;
89 #endif
90 
91 	nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
92 	if (!nc) {
93 		printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
94 		ret = -ENOMEM;
95 		goto no_res;
96 	}
97 	mtd = (struct mtd_info *)(nc + 1);
98 
99 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
100 	if (!res) {
101 		ret = -ENODEV;
102 		goto no_res;
103 	}
104 
105 	io_base = ioremap(res->start, resource_size(res));
106 	if (!io_base) {
107 		printk(KERN_ERR "orion_nand: ioremap failed\n");
108 		ret = -EIO;
109 		goto no_res;
110 	}
111 
112 	board = pdev->dev.platform_data;
113 
114 	mtd->priv = nc;
115 	mtd->owner = THIS_MODULE;
116 
117 	nc->priv = board;
118 	nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
119 	nc->cmd_ctrl = orion_nand_cmd_ctrl;
120 	nc->read_buf = orion_nand_read_buf;
121 	nc->ecc.mode = NAND_ECC_SOFT;
122 
123 	if (board->chip_delay)
124 		nc->chip_delay = board->chip_delay;
125 
126 	if (board->width == 16)
127 		nc->options |= NAND_BUSWIDTH_16;
128 
129 	if (board->dev_ready)
130 		nc->dev_ready = board->dev_ready;
131 
132 	platform_set_drvdata(pdev, mtd);
133 
134 	if (nand_scan(mtd, 1)) {
135 		ret = -ENXIO;
136 		goto no_dev;
137 	}
138 
139 #ifdef CONFIG_MTD_PARTITIONS
140 #ifdef CONFIG_MTD_CMDLINE_PARTS
141 	mtd->name = "orion_nand";
142 	num_part = parse_mtd_partitions(mtd, part_probes, &partitions, 0);
143 #endif
144 	/* If cmdline partitions have been passed, let them be used */
145 	if (num_part <= 0) {
146 		num_part = board->nr_parts;
147 		partitions = board->parts;
148 	}
149 
150 	if (partitions && num_part > 0)
151 		ret = add_mtd_partitions(mtd, partitions, num_part);
152 	else
153 		ret = add_mtd_device(mtd);
154 #else
155 	ret = add_mtd_device(mtd);
156 #endif
157 
158 	if (ret) {
159 		nand_release(mtd);
160 		goto no_dev;
161 	}
162 
163 	return 0;
164 
165 no_dev:
166 	platform_set_drvdata(pdev, NULL);
167 	iounmap(io_base);
168 no_res:
169 	kfree(nc);
170 
171 	return ret;
172 }
173 
orion_nand_remove(struct platform_device * pdev)174 static int __devexit orion_nand_remove(struct platform_device *pdev)
175 {
176 	struct mtd_info *mtd = platform_get_drvdata(pdev);
177 	struct nand_chip *nc = mtd->priv;
178 
179 	nand_release(mtd);
180 
181 	iounmap(nc->IO_ADDR_W);
182 
183 	kfree(nc);
184 
185 	return 0;
186 }
187 
188 static struct platform_driver orion_nand_driver = {
189 	.remove		= __devexit_p(orion_nand_remove),
190 	.driver		= {
191 		.name	= "orion_nand",
192 		.owner	= THIS_MODULE,
193 	},
194 };
195 
orion_nand_init(void)196 static int __init orion_nand_init(void)
197 {
198 	return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
199 }
200 
orion_nand_exit(void)201 static void __exit orion_nand_exit(void)
202 {
203 	platform_driver_unregister(&orion_nand_driver);
204 }
205 
206 module_init(orion_nand_init);
207 module_exit(orion_nand_exit);
208 
209 MODULE_LICENSE("GPL");
210 MODULE_AUTHOR("Tzachi Perelstein");
211 MODULE_DESCRIPTION("NAND glue for Orion platforms");
212 MODULE_ALIAS("platform:orion_nand");
213