2 * drivers/mtd/nand/orion_nand.c
4 * NAND support for Marvell Orion SoC platforms
6 * Tzachi Perelstein <tzachi@marvell.com>
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.
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/nand.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/clk.h>
21 #include <linux/err.h>
23 #include <asm/sizes.h>
24 #include <linux/platform_data/mtd-orion_nand.h>
26 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
28 struct nand_chip *nc = mtd_to_nand(mtd);
29 struct orion_nand_data *board = nand_get_controller_data(nc);
32 if (cmd == NAND_CMD_NONE)
36 offs = (1 << board->cle);
37 else if (ctrl & NAND_ALE)
38 offs = (1 << board->ale);
42 if (nc->options & NAND_BUSWIDTH_16)
45 writeb(cmd, nc->IO_ADDR_W + offs);
48 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
50 struct nand_chip *chip = mtd_to_nand(mtd);
51 void __iomem *io_base = chip->IO_ADDR_R;
55 while (len && (unsigned long)buf & 7) {
56 *buf++ = readb(io_base);
59 buf64 = (uint64_t *)buf;
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.
66 register uint64_t x asm ("r2");
68 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
73 buf[i++] = readb(io_base);
76 static int __init orion_nand_probe(struct platform_device *pdev)
80 struct orion_nand_data *board;
83 void __iomem *io_base;
87 nc = devm_kzalloc(&pdev->dev,
88 sizeof(struct nand_chip),
92 mtd = nand_to_mtd(nc);
94 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
95 io_base = devm_ioremap_resource(&pdev->dev, res);
98 return PTR_ERR(io_base);
100 if (pdev->dev.of_node) {
101 board = devm_kzalloc(&pdev->dev, sizeof(struct orion_nand_data),
105 if (!of_property_read_u32(pdev->dev.of_node, "cle", &val))
106 board->cle = (u8)val;
109 if (!of_property_read_u32(pdev->dev.of_node, "ale", &val))
110 board->ale = (u8)val;
113 if (!of_property_read_u32(pdev->dev.of_node,
115 board->width = (u8)val * 8;
118 if (!of_property_read_u32(pdev->dev.of_node,
120 board->chip_delay = (u8)val;
122 board = dev_get_platdata(&pdev->dev);
125 mtd->dev.parent = &pdev->dev;
127 nand_set_controller_data(nc, board);
128 nand_set_flash_node(nc, pdev->dev.of_node);
129 nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
130 nc->cmd_ctrl = orion_nand_cmd_ctrl;
131 nc->read_buf = orion_nand_read_buf;
132 nc->ecc.mode = NAND_ECC_SOFT;
133 nc->ecc.algo = NAND_ECC_HAMMING;
135 if (board->chip_delay)
136 nc->chip_delay = board->chip_delay;
138 WARN(board->width > 16,
139 "%d bit bus width out of range",
142 if (board->width == 16)
143 nc->options |= NAND_BUSWIDTH_16;
145 if (board->dev_ready)
146 nc->dev_ready = board->dev_ready;
148 platform_set_drvdata(pdev, mtd);
150 /* Not all platforms can gate the clock, so it is not
151 an error if the clock does not exists. */
152 clk = clk_get(&pdev->dev, NULL);
154 clk_prepare_enable(clk);
158 if (nand_scan(mtd, 1)) {
163 mtd->name = "orion_nand";
164 ret = mtd_device_register(mtd, board->parts, board->nr_parts);
174 clk_disable_unprepare(clk);
181 static int orion_nand_remove(struct platform_device *pdev)
183 struct mtd_info *mtd = platform_get_drvdata(pdev);
188 clk = clk_get(&pdev->dev, NULL);
190 clk_disable_unprepare(clk);
198 static const struct of_device_id orion_nand_of_match_table[] = {
199 { .compatible = "marvell,orion-nand", },
202 MODULE_DEVICE_TABLE(of, orion_nand_of_match_table);
205 static struct platform_driver orion_nand_driver = {
206 .remove = orion_nand_remove,
208 .name = "orion_nand",
209 .of_match_table = of_match_ptr(orion_nand_of_match_table),
213 module_platform_driver_probe(orion_nand_driver, orion_nand_probe);
215 MODULE_LICENSE("GPL");
216 MODULE_AUTHOR("Tzachi Perelstein");
217 MODULE_DESCRIPTION("NAND glue for Orion platforms");
218 MODULE_ALIAS("platform:orion_nand");