drivers/mtd/nand/pasemi_nand.c

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