1 /*
2 * NAND support for Marvell Orion SoC platforms
3 *
4 * Tzachi Perelstein <tzachi@marvell.com>
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/of.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/rawnand.h>
17 #include <linux/mtd/partitions.h>
18 #include <linux/clk.h>
19 #include <linux/err.h>
20 #include <linux/io.h>
21 #include <linux/sizes.h>
22 #include <linux/platform_data/mtd-orion_nand.h>
23
24 struct orion_nand_info {
25 struct nand_controller controller;
26 struct nand_chip chip;
27 struct clk *clk;
28 };
29
orion_nand_cmd_ctrl(struct nand_chip * nc,int cmd,unsigned int ctrl)30 static void orion_nand_cmd_ctrl(struct nand_chip *nc, int cmd,
31 unsigned int ctrl)
32 {
33 struct orion_nand_data *board = nand_get_controller_data(nc);
34 u32 offs;
35
36 if (cmd == NAND_CMD_NONE)
37 return;
38
39 if (ctrl & NAND_CLE)
40 offs = (1 << board->cle);
41 else if (ctrl & NAND_ALE)
42 offs = (1 << board->ale);
43 else
44 return;
45
46 if (nc->options & NAND_BUSWIDTH_16)
47 offs <<= 1;
48
49 writeb(cmd, nc->legacy.IO_ADDR_W + offs);
50 }
51
orion_nand_read_buf(struct nand_chip * chip,uint8_t * buf,int len)52 static void orion_nand_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
53 {
54 void __iomem *io_base = chip->legacy.IO_ADDR_R;
55 #if defined(__LINUX_ARM_ARCH__) && __LINUX_ARM_ARCH__ >= 5
56 uint64_t *buf64;
57 #endif
58 int i = 0;
59
60 while (len && (unsigned long)buf & 7) {
61 *buf++ = readb(io_base);
62 len--;
63 }
64 #if defined(__LINUX_ARM_ARCH__) && __LINUX_ARM_ARCH__ >= 5
65 buf64 = (uint64_t *)buf;
66 while (i < len/8) {
67 /*
68 * Since GCC has no proper constraint (PR 43518)
69 * force x variable to r2/r3 registers as ldrd instruction
70 * requires first register to be even.
71 */
72 register uint64_t x asm ("r2");
73
74 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
75 buf64[i++] = x;
76 }
77 i *= 8;
78 #else
79 readsl(io_base, buf, len/4);
80 i = len / 4 * 4;
81 #endif
82 while (i < len)
83 buf[i++] = readb(io_base);
84 }
85
orion_nand_attach_chip(struct nand_chip * chip)86 static int orion_nand_attach_chip(struct nand_chip *chip)
87 {
88 chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
89
90 if (chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN)
91 chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
92
93 return 0;
94 }
95
96 static const struct nand_controller_ops orion_nand_ops = {
97 .attach_chip = orion_nand_attach_chip,
98 };
99
orion_nand_probe(struct platform_device * pdev)100 static int __init orion_nand_probe(struct platform_device *pdev)
101 {
102 struct orion_nand_info *info;
103 struct mtd_info *mtd;
104 struct nand_chip *nc;
105 struct orion_nand_data *board;
106 struct resource *res;
107 void __iomem *io_base;
108 int ret = 0;
109 u32 val = 0;
110
111 info = devm_kzalloc(&pdev->dev,
112 sizeof(struct orion_nand_info),
113 GFP_KERNEL);
114 if (!info)
115 return -ENOMEM;
116 nc = &info->chip;
117 mtd = nand_to_mtd(nc);
118
119 nand_controller_init(&info->controller);
120 info->controller.ops = &orion_nand_ops;
121 nc->controller = &info->controller;
122
123 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
124 io_base = devm_ioremap_resource(&pdev->dev, res);
125
126 if (IS_ERR(io_base))
127 return PTR_ERR(io_base);
128
129 if (pdev->dev.of_node) {
130 board = devm_kzalloc(&pdev->dev, sizeof(struct orion_nand_data),
131 GFP_KERNEL);
132 if (!board)
133 return -ENOMEM;
134 if (!of_property_read_u32(pdev->dev.of_node, "cle", &val))
135 board->cle = (u8)val;
136 else
137 board->cle = 0;
138 if (!of_property_read_u32(pdev->dev.of_node, "ale", &val))
139 board->ale = (u8)val;
140 else
141 board->ale = 1;
142 if (!of_property_read_u32(pdev->dev.of_node,
143 "bank-width", &val))
144 board->width = (u8)val * 8;
145 else
146 board->width = 8;
147 if (!of_property_read_u32(pdev->dev.of_node,
148 "chip-delay", &val))
149 board->chip_delay = (u8)val;
150 } else {
151 board = dev_get_platdata(&pdev->dev);
152 }
153
154 mtd->dev.parent = &pdev->dev;
155
156 nand_set_controller_data(nc, board);
157 nand_set_flash_node(nc, pdev->dev.of_node);
158 nc->legacy.IO_ADDR_R = nc->legacy.IO_ADDR_W = io_base;
159 nc->legacy.cmd_ctrl = orion_nand_cmd_ctrl;
160 nc->legacy.read_buf = orion_nand_read_buf;
161
162 if (board->chip_delay)
163 nc->legacy.chip_delay = board->chip_delay;
164
165 WARN(board->width > 16,
166 "%d bit bus width out of range",
167 board->width);
168
169 if (board->width == 16)
170 nc->options |= NAND_BUSWIDTH_16;
171
172 platform_set_drvdata(pdev, info);
173
174 /* Not all platforms can gate the clock, so it is not
175 an error if the clock does not exists. */
176 info->clk = devm_clk_get(&pdev->dev, NULL);
177 if (IS_ERR(info->clk)) {
178 ret = PTR_ERR(info->clk);
179 if (ret == -ENOENT) {
180 info->clk = NULL;
181 } else {
182 dev_err(&pdev->dev, "failed to get clock!\n");
183 return ret;
184 }
185 }
186
187 ret = clk_prepare_enable(info->clk);
188 if (ret) {
189 dev_err(&pdev->dev, "failed to prepare clock!\n");
190 return ret;
191 }
192
193 ret = nand_scan(nc, 1);
194 if (ret)
195 goto no_dev;
196
197 mtd->name = "orion_nand";
198 ret = mtd_device_register(mtd, board->parts, board->nr_parts);
199 if (ret) {
200 nand_cleanup(nc);
201 goto no_dev;
202 }
203
204 return 0;
205
206 no_dev:
207 clk_disable_unprepare(info->clk);
208 return ret;
209 }
210
orion_nand_remove(struct platform_device * pdev)211 static int orion_nand_remove(struct platform_device *pdev)
212 {
213 struct orion_nand_info *info = platform_get_drvdata(pdev);
214 struct nand_chip *chip = &info->chip;
215 int ret;
216
217 ret = mtd_device_unregister(nand_to_mtd(chip));
218 WARN_ON(ret);
219
220 nand_cleanup(chip);
221
222 clk_disable_unprepare(info->clk);
223
224 return 0;
225 }
226
227 #ifdef CONFIG_OF
228 static const struct of_device_id orion_nand_of_match_table[] = {
229 { .compatible = "marvell,orion-nand", },
230 {},
231 };
232 MODULE_DEVICE_TABLE(of, orion_nand_of_match_table);
233 #endif
234
235 static struct platform_driver orion_nand_driver = {
236 .remove = orion_nand_remove,
237 .driver = {
238 .name = "orion_nand",
239 .of_match_table = of_match_ptr(orion_nand_of_match_table),
240 },
241 };
242
243 module_platform_driver_probe(orion_nand_driver, orion_nand_probe);
244
245 MODULE_LICENSE("GPL");
246 MODULE_AUTHOR("Tzachi Perelstein");
247 MODULE_DESCRIPTION("NAND glue for Orion platforms");
248 MODULE_ALIAS("platform:orion_nand");
249