xref: /openbmc/linux/drivers/mtd/nand/raw/pasemi_nand.c (revision 828ff2ad)
1 /*
2  * Copyright (C) 2006-2007 PA Semi, Inc
3  *
4  * Author: Egor Martovetsky <egor@pasemi.com>
5  * Maintained by: Olof Johansson <olof@lixom.net>
6  *
7  * Driver for the PWRficient onchip NAND flash interface
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  */
22 
23 #undef DEBUG
24 
25 #include <linux/slab.h>
26 #include <linux/module.h>
27 #include <linux/mtd/mtd.h>
28 #include <linux/mtd/rawnand.h>
29 #include <linux/mtd/nand_ecc.h>
30 #include <linux/of_address.h>
31 #include <linux/of_irq.h>
32 #include <linux/of_platform.h>
33 #include <linux/platform_device.h>
34 #include <linux/pci.h>
35 
36 #include <asm/io.h>
37 
38 #define LBICTRL_LPCCTL_NR		0x00004000
39 #define CLE_PIN_CTL			15
40 #define ALE_PIN_CTL			14
41 
42 static unsigned int lpcctl;
43 static struct mtd_info *pasemi_nand_mtd;
44 static const char driver_name[] = "pasemi-nand";
45 
46 static void pasemi_read_buf(struct nand_chip *chip, u_char *buf, int len)
47 {
48 	while (len > 0x800) {
49 		memcpy_fromio(buf, chip->legacy.IO_ADDR_R, 0x800);
50 		buf += 0x800;
51 		len -= 0x800;
52 	}
53 	memcpy_fromio(buf, chip->legacy.IO_ADDR_R, len);
54 }
55 
56 static void pasemi_write_buf(struct nand_chip *chip, const u_char *buf,
57 			     int len)
58 {
59 	while (len > 0x800) {
60 		memcpy_toio(chip->legacy.IO_ADDR_R, buf, 0x800);
61 		buf += 0x800;
62 		len -= 0x800;
63 	}
64 	memcpy_toio(chip->legacy.IO_ADDR_R, buf, len);
65 }
66 
67 static void pasemi_hwcontrol(struct nand_chip *chip, int cmd,
68 			     unsigned int ctrl)
69 {
70 	if (cmd == NAND_CMD_NONE)
71 		return;
72 
73 	if (ctrl & NAND_CLE)
74 		out_8(chip->legacy.IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
75 	else
76 		out_8(chip->legacy.IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
77 
78 	/* Push out posted writes */
79 	eieio();
80 	inl(lpcctl);
81 }
82 
83 int pasemi_device_ready(struct nand_chip *chip)
84 {
85 	return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
86 }
87 
88 static int pasemi_nand_probe(struct platform_device *ofdev)
89 {
90 	struct device *dev = &ofdev->dev;
91 	struct pci_dev *pdev;
92 	struct device_node *np = dev->of_node;
93 	struct resource res;
94 	struct nand_chip *chip;
95 	int err = 0;
96 
97 	err = of_address_to_resource(np, 0, &res);
98 
99 	if (err)
100 		return -EINVAL;
101 
102 	/* We only support one device at the moment */
103 	if (pasemi_nand_mtd)
104 		return -ENODEV;
105 
106 	dev_dbg(dev, "pasemi_nand at %pR\n", &res);
107 
108 	/* Allocate memory for MTD device structure and private data */
109 	chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
110 	if (!chip) {
111 		err = -ENOMEM;
112 		goto out;
113 	}
114 
115 	pasemi_nand_mtd = nand_to_mtd(chip);
116 
117 	/* Link the private data with the MTD structure */
118 	pasemi_nand_mtd->dev.parent = dev;
119 
120 	chip->legacy.IO_ADDR_R = of_iomap(np, 0);
121 	chip->legacy.IO_ADDR_W = chip->legacy.IO_ADDR_R;
122 
123 	if (!chip->legacy.IO_ADDR_R) {
124 		err = -EIO;
125 		goto out_mtd;
126 	}
127 
128 	pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
129 	if (!pdev) {
130 		err = -ENODEV;
131 		goto out_ior;
132 	}
133 
134 	lpcctl = pci_resource_start(pdev, 0);
135 	pci_dev_put(pdev);
136 
137 	if (!request_region(lpcctl, 4, driver_name)) {
138 		err = -EBUSY;
139 		goto out_ior;
140 	}
141 
142 	chip->legacy.cmd_ctrl = pasemi_hwcontrol;
143 	chip->legacy.dev_ready = pasemi_device_ready;
144 	chip->legacy.read_buf = pasemi_read_buf;
145 	chip->legacy.write_buf = pasemi_write_buf;
146 	chip->legacy.chip_delay = 0;
147 	chip->ecc.mode = NAND_ECC_SOFT;
148 	chip->ecc.algo = NAND_ECC_HAMMING;
149 
150 	/* Enable the following for a flash based bad block table */
151 	chip->bbt_options = NAND_BBT_USE_FLASH;
152 
153 	/* Scan to find existence of the device */
154 	err = nand_scan(chip, 1);
155 	if (err)
156 		goto out_lpc;
157 
158 	if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
159 		dev_err(dev, "Unable to register MTD device\n");
160 		err = -ENODEV;
161 		goto out_lpc;
162 	}
163 
164 	dev_info(dev, "PA Semi NAND flash at %pR, control at I/O %x\n", &res,
165 		 lpcctl);
166 
167 	return 0;
168 
169  out_lpc:
170 	release_region(lpcctl, 4);
171  out_ior:
172 	iounmap(chip->legacy.IO_ADDR_R);
173  out_mtd:
174 	kfree(chip);
175  out:
176 	return err;
177 }
178 
179 static int pasemi_nand_remove(struct platform_device *ofdev)
180 {
181 	struct nand_chip *chip;
182 
183 	if (!pasemi_nand_mtd)
184 		return 0;
185 
186 	chip = mtd_to_nand(pasemi_nand_mtd);
187 
188 	/* Release resources, unregister device */
189 	nand_release(chip);
190 
191 	release_region(lpcctl, 4);
192 
193 	iounmap(chip->legacy.IO_ADDR_R);
194 
195 	/* Free the MTD device structure */
196 	kfree(chip);
197 
198 	pasemi_nand_mtd = NULL;
199 
200 	return 0;
201 }
202 
203 static const struct of_device_id pasemi_nand_match[] =
204 {
205 	{
206 		.compatible   = "pasemi,localbus-nand",
207 	},
208 	{},
209 };
210 
211 MODULE_DEVICE_TABLE(of, pasemi_nand_match);
212 
213 static struct platform_driver pasemi_nand_driver =
214 {
215 	.driver = {
216 		.name = driver_name,
217 		.of_match_table = pasemi_nand_match,
218 	},
219 	.probe		= pasemi_nand_probe,
220 	.remove		= pasemi_nand_remove,
221 };
222 
223 module_platform_driver(pasemi_nand_driver);
224 
225 MODULE_LICENSE("GPL");
226 MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
227 MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");
228