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/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 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) {
 115                 printk(KERN_WARNING
 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;
 151         chip->dev_ready = pasemi_device_ready;
 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 */
 158         chip->bbt_options = NAND_BBT_USE_FLASH;
 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 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 <egor@pasemi.com>");
 236 MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");