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->priv;
  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->priv;
  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->priv;
  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 pci_dev *pdev;
  96         struct device_node *np = ofdev->dev.of_node;
  97         struct resource res;
  98         struct nand_chip *chip;
  99         int err = 0;
 100
 101         err = of_address_to_resource(np, 0, &res);
 102
 103         if (err)
 104                 return -EINVAL;
 105
 106         /* We only support one device at the moment */
 107         if (pasemi_nand_mtd)
 108                 return -ENODEV;
 109
 110         pr_debug("pasemi_nand at %pR\n", &res);
 111
 112         /* Allocate memory for MTD device structure and private data */
 113         pasemi_nand_mtd = kzalloc(sizeof(struct mtd_info) +
 114                                   sizeof(struct nand_chip), GFP_KERNEL);
 115         if (!pasemi_nand_mtd) {
 116                 printk(KERN_WARNING
 117                        "Unable to allocate PASEMI NAND MTD device structure\n");
 118                 err = -ENOMEM;
 119                 goto out;
 120         }
 121
 122         /* Get pointer to private data */
 123         chip = (struct nand_chip *)&pasemi_nand_mtd[1];
 124
 125         /* Link the private data with the MTD structure */
 126         pasemi_nand_mtd->priv = chip;
 127         pasemi_nand_mtd->owner = THIS_MODULE;
 128
 129         chip->IO_ADDR_R = of_iomap(np, 0);
 130         chip->IO_ADDR_W = chip->IO_ADDR_R;
 131
 132         if (!chip->IO_ADDR_R) {
 133                 err = -EIO;
 134                 goto out_mtd;
 135         }
 136
 137         pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
 138         if (!pdev) {
 139                 err = -ENODEV;
 140                 goto out_ior;
 141         }
 142
 143         lpcctl = pci_resource_start(pdev, 0);
 144         pci_dev_put(pdev);
 145
 146         if (!request_region(lpcctl, 4, driver_name)) {
 147                 err = -EBUSY;
 148                 goto out_ior;
 149         }
 150
 151         chip->cmd_ctrl = pasemi_hwcontrol;
 152         chip->dev_ready = pasemi_device_ready;
 153         chip->read_buf = pasemi_read_buf;
 154         chip->write_buf = pasemi_write_buf;
 155         chip->chip_delay = 0;
 156         chip->ecc.mode = NAND_ECC_SOFT;
 157
 158         /* Enable the following for a flash based bad block table */
 159         chip->bbt_options = NAND_BBT_USE_FLASH;
 160
 161         /* Scan to find existence of the device */
 162         if (nand_scan(pasemi_nand_mtd, 1)) {
 163                 err = -ENXIO;
 164                 goto out_lpc;
 165         }
 166
 167         if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
 168                 printk(KERN_ERR "pasemi_nand: Unable to register MTD device\n");
 169                 err = -ENODEV;
 170                 goto out_lpc;
 171         }
 172
 173         printk(KERN_INFO "PA Semi NAND flash at %08llx, control at I/O %x\n",
 174                res.start, lpcctl);
 175
 176         return 0;
 177
 178  out_lpc:
 179         release_region(lpcctl, 4);
 180  out_ior:
 181         iounmap(chip->IO_ADDR_R);
 182  out_mtd:
 183         kfree(pasemi_nand_mtd);
 184  out:
 185         return err;
 186 }
 187
 188 static int pasemi_nand_remove(struct platform_device *ofdev)
 189 {
 190         struct nand_chip *chip;
 191
 192         if (!pasemi_nand_mtd)
 193                 return 0;
 194
 195         chip = pasemi_nand_mtd->priv;
 196
 197         /* Release resources, unregister device */
 198         nand_release(pasemi_nand_mtd);
 199
 200         release_region(lpcctl, 4);
 201
 202         iounmap(chip->IO_ADDR_R);
 203
 204         /* Free the MTD device structure */
 205         kfree(pasemi_nand_mtd);
 206
 207         pasemi_nand_mtd = NULL;
 208
 209         return 0;
 210 }
 211
 212 static const struct of_device_id pasemi_nand_match[] =
 213 {
 214         {
 215                 .compatible   = "pasemi,localbus-nand",
 216         },
 217         {},
 218 };
 219
 220 MODULE_DEVICE_TABLE(of, pasemi_nand_match);
 221
 222 static struct platform_driver pasemi_nand_driver =
 223 {
 224         .driver = {
 225                 .name = driver_name,
 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");