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pasemi_nand.c
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1 /*
2  * Copyright (C) 2006-2007 PA Semi, Inc
3  *
4  * Author: Egor Martovetsky <[email protected]>
5  * Maintained by: Olof Johansson <[email protected]>
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/init.h>
27 #include <linux/module.h>
28 #include <linux/mtd/mtd.h>
29 #include <linux/mtd/nand.h>
30 #include <linux/mtd/nand_ecc.h>
31 #include <linux/of_platform.h>
32 #include <linux/platform_device.h>
33 #include <linux/pci.h>
34 
35 #include <asm/io.h>
36 
37 #define LBICTRL_LPCCTL_NR 0x00004000
38 #define CLE_PIN_CTL 15
39 #define ALE_PIN_CTL 14
40 
41 static unsigned int lpcctl;
42 static struct mtd_info *pasemi_nand_mtd;
43 static const char driver_name[] = "pasemi-nand";
44 
45 static void pasemi_read_buf(struct mtd_info *mtd, u_char *buf, int len)
46 {
47  struct nand_chip *chip = mtd->priv;
48 
49  while (len > 0x800) {
50  memcpy_fromio(buf, chip->IO_ADDR_R, 0x800);
51  buf += 0x800;
52  len -= 0x800;
53  }
54  memcpy_fromio(buf, chip->IO_ADDR_R, len);
55 }
56 
57 static void pasemi_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
58 {
59  struct nand_chip *chip = mtd->priv;
60 
61  while (len > 0x800) {
62  memcpy_toio(chip->IO_ADDR_R, buf, 0x800);
63  buf += 0x800;
64  len -= 0x800;
65  }
66  memcpy_toio(chip->IO_ADDR_R, buf, len);
67 }
68 
69 static void pasemi_hwcontrol(struct mtd_info *mtd, int cmd,
70  unsigned int ctrl)
71 {
72  struct nand_chip *chip = mtd->priv;
73 
74  if (cmd == NAND_CMD_NONE)
75  return;
76 
77  if (ctrl & NAND_CLE)
78  out_8(chip->IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
79  else
80  out_8(chip->IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
81 
82  /* Push out posted writes */
83  eieio();
84  inl(lpcctl);
85 }
86 
87 int pasemi_device_ready(struct mtd_info *mtd)
88 {
89  return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
90 }
91 
92 static int __devinit pasemi_nand_probe(struct platform_device *ofdev)
93 {
94  struct pci_dev *pdev;
95  struct device_node *np = ofdev->dev.of_node;
96  struct resource res;
97  struct nand_chip *chip;
98  int err = 0;
99 
100  err = of_address_to_resource(np, 0, &res);
101 
102  if (err)
103  return -EINVAL;
104 
105  /* We only support one device at the moment */
106  if (pasemi_nand_mtd)
107  return -ENODEV;
108 
109  pr_debug("pasemi_nand at %pR\n", &res);
110 
111  /* Allocate memory for MTD device structure and private data */
112  pasemi_nand_mtd = kzalloc(sizeof(struct mtd_info) +
113  sizeof(struct nand_chip), GFP_KERNEL);
114  if (!pasemi_nand_mtd) {
116  "Unable to allocate PASEMI NAND MTD device structure\n");
117  err = -ENOMEM;
118  goto out;
119  }
120 
121  /* Get pointer to private data */
122  chip = (struct nand_chip *)&pasemi_nand_mtd[1];
123 
124  /* Link the private data with the MTD structure */
125  pasemi_nand_mtd->priv = chip;
126  pasemi_nand_mtd->owner = THIS_MODULE;
127 
128  chip->IO_ADDR_R = of_iomap(np, 0);
129  chip->IO_ADDR_W = chip->IO_ADDR_R;
130 
131  if (!chip->IO_ADDR_R) {
132  err = -EIO;
133  goto out_mtd;
134  }
135 
136  pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
137  if (!pdev) {
138  err = -ENODEV;
139  goto out_ior;
140  }
141 
142  lpcctl = pci_resource_start(pdev, 0);
143  pci_dev_put(pdev);
144 
145  if (!request_region(lpcctl, 4, driver_name)) {
146  err = -EBUSY;
147  goto out_ior;
148  }
149 
150  chip->cmd_ctrl = pasemi_hwcontrol;
152  chip->read_buf = pasemi_read_buf;
153  chip->write_buf = pasemi_write_buf;
154  chip->chip_delay = 0;
155  chip->ecc.mode = NAND_ECC_SOFT;
156 
157  /* Enable the following for a flash based bad block table */
159 
160  /* Scan to find existence of the device */
161  if (nand_scan(pasemi_nand_mtd, 1)) {
162  err = -ENXIO;
163  goto out_lpc;
164  }
165 
166  if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
167  printk(KERN_ERR "pasemi_nand: Unable to register MTD device\n");
168  err = -ENODEV;
169  goto out_lpc;
170  }
171 
172  printk(KERN_INFO "PA Semi NAND flash at %08llx, control at I/O %x\n",
173  res.start, lpcctl);
174 
175  return 0;
176 
177  out_lpc:
178  release_region(lpcctl, 4);
179  out_ior:
180  iounmap(chip->IO_ADDR_R);
181  out_mtd:
182  kfree(pasemi_nand_mtd);
183  out:
184  return err;
185 }
186 
187 static int __devexit pasemi_nand_remove(struct platform_device *ofdev)
188 {
189  struct nand_chip *chip;
190 
191  if (!pasemi_nand_mtd)
192  return 0;
193 
194  chip = pasemi_nand_mtd->priv;
195 
196  /* Release resources, unregister device */
197  nand_release(pasemi_nand_mtd);
198 
199  release_region(lpcctl, 4);
200 
201  iounmap(chip->IO_ADDR_R);
202 
203  /* Free the MTD device structure */
204  kfree(pasemi_nand_mtd);
205 
206  pasemi_nand_mtd = NULL;
207 
208  return 0;
209 }
210 
211 static const struct of_device_id pasemi_nand_match[] =
212 {
213  {
214  .compatible = "pasemi,localbus-nand",
215  },
216  {},
217 };
218 
219 MODULE_DEVICE_TABLE(of, pasemi_nand_match);
220 
221 static struct platform_driver pasemi_nand_driver =
222 {
223  .driver = {
224  .name = (char*)driver_name,
225  .owner = THIS_MODULE,
226  .of_match_table = pasemi_nand_match,
227  },
228  .probe = pasemi_nand_probe,
229  .remove = pasemi_nand_remove,
230 };
231 
232 module_platform_driver(pasemi_nand_driver);
233 
234 MODULE_LICENSE("GPL");
235 MODULE_AUTHOR("Egor Martovetsky <[email protected]>");
236 MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");