drivers/mtd/nand/raw/pasemi_nand.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2006-2007 PA Semi, Inc
   4  *
   5  * Author: Egor Martovetsky <egor@pasemi.com>
   6  * Maintained by: Olof Johansson <olof@lixom.net>
   7  *
   8  * Driver for the PWRficient onchip NAND flash interface
   9  */
  10
  11 #undef DEBUG
  12
  13 #include <linux/slab.h>
  14 #include <linux/module.h>
  15 #include <linux/mtd/mtd.h>
  16 #include <linux/mtd/rawnand.h>
  17 #include <linux/mtd/nand_ecc.h>
  18 #include <linux/of_address.h>
  19 #include <linux/of_irq.h>
  20 #include <linux/of_platform.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/pci.h>
  23
  24 #include <asm/io.h>
  25
  26 #define LBICTRL_LPCCTL_NR               0x00004000
  27 #define CLE_PIN_CTL                     15
  28 #define ALE_PIN_CTL                     14
  29
  30 static unsigned int lpcctl;
  31 static struct mtd_info *pasemi_nand_mtd;
  32 static const char driver_name[] = "pasemi-nand";
  33
  34 static void pasemi_read_buf(struct nand_chip *chip, u_char *buf, int len)
  35 {
  36         while (len > 0x800) {
  37                 memcpy_fromio(buf, chip->legacy.IO_ADDR_R, 0x800);
  38                 buf += 0x800;
  39                 len -= 0x800;
  40         }
  41         memcpy_fromio(buf, chip->legacy.IO_ADDR_R, len);
  42 }
  43
  44 static void pasemi_write_buf(struct nand_chip *chip, const u_char *buf,
  45                              int len)
  46 {
  47         while (len > 0x800) {
  48                 memcpy_toio(chip->legacy.IO_ADDR_R, buf, 0x800);
  49                 buf += 0x800;
  50                 len -= 0x800;
  51         }
  52         memcpy_toio(chip->legacy.IO_ADDR_R, buf, len);
  53 }
  54
  55 static void pasemi_hwcontrol(struct nand_chip *chip, int cmd,
  56                              unsigned int ctrl)
  57 {
  58         if (cmd == NAND_CMD_NONE)
  59                 return;
  60
  61         if (ctrl & NAND_CLE)
  62                 out_8(chip->legacy.IO_ADDR_W + (1 << CLE_PIN_CTL), cmd);
  63         else
  64                 out_8(chip->legacy.IO_ADDR_W + (1 << ALE_PIN_CTL), cmd);
  65
  66         /* Push out posted writes */
  67         eieio();
  68         inl(lpcctl);
  69 }
  70
  71 static int pasemi_device_ready(struct nand_chip *chip)
  72 {
  73         return !!(inl(lpcctl) & LBICTRL_LPCCTL_NR);
  74 }
  75
  76 static int pasemi_nand_probe(struct platform_device *ofdev)
  77 {
  78         struct device *dev = &ofdev->dev;
  79         struct pci_dev *pdev;
  80         struct device_node *np = dev->of_node;
  81         struct resource res;
  82         struct nand_chip *chip;
  83         int err = 0;
  84
  85         err = of_address_to_resource(np, 0, &res);
  86
  87         if (err)
  88                 return -EINVAL;
  89
  90         /* We only support one device at the moment */
  91         if (pasemi_nand_mtd)
  92                 return -ENODEV;
  93
  94         dev_dbg(dev, "pasemi_nand at %pR\n", &res);
  95
  96         /* Allocate memory for MTD device structure and private data */
  97         chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
  98         if (!chip) {
  99                 err = -ENOMEM;
 100                 goto out;
 101         }
 102
 103         pasemi_nand_mtd = nand_to_mtd(chip);
 104
 105         /* Link the private data with the MTD structure */
 106         pasemi_nand_mtd->dev.parent = dev;
 107
 108         chip->legacy.IO_ADDR_R = of_iomap(np, 0);
 109         chip->legacy.IO_ADDR_W = chip->legacy.IO_ADDR_R;
 110
 111         if (!chip->legacy.IO_ADDR_R) {
 112                 err = -EIO;
 113                 goto out_mtd;
 114         }
 115
 116         pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa008, NULL);
 117         if (!pdev) {
 118                 err = -ENODEV;
 119                 goto out_ior;
 120         }
 121
 122         lpcctl = pci_resource_start(pdev, 0);
 123         pci_dev_put(pdev);
 124
 125         if (!request_region(lpcctl, 4, driver_name)) {
 126                 err = -EBUSY;
 127                 goto out_ior;
 128         }
 129
 130         chip->legacy.cmd_ctrl = pasemi_hwcontrol;
 131         chip->legacy.dev_ready = pasemi_device_ready;
 132         chip->legacy.read_buf = pasemi_read_buf;
 133         chip->legacy.write_buf = pasemi_write_buf;
 134         chip->legacy.chip_delay = 0;
 135         chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
 136         chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
 137
 138         /* Enable the following for a flash based bad block table */
 139         chip->bbt_options = NAND_BBT_USE_FLASH;
 140
 141         /* Scan to find existence of the device */
 142         err = nand_scan(chip, 1);
 143         if (err)
 144                 goto out_lpc;
 145
 146         if (mtd_device_register(pasemi_nand_mtd, NULL, 0)) {
 147                 dev_err(dev, "Unable to register MTD device\n");
 148                 err = -ENODEV;
 149                 goto out_cleanup_nand;
 150         }
 151
 152         dev_info(dev, "PA Semi NAND flash at %pR, control at I/O %x\n", &res,
 153                  lpcctl);
 154
 155         return 0;
 156
 157  out_cleanup_nand:
 158         nand_cleanup(chip);
 159  out_lpc:
 160         release_region(lpcctl, 4);
 161  out_ior:
 162         iounmap(chip->legacy.IO_ADDR_R);
 163  out_mtd:
 164         kfree(chip);
 165  out:
 166         return err;
 167 }
 168
 169 static int pasemi_nand_remove(struct platform_device *ofdev)
 170 {
 171         struct nand_chip *chip;
 172         int ret;
 173
 174         if (!pasemi_nand_mtd)
 175                 return 0;
 176
 177         chip = mtd_to_nand(pasemi_nand_mtd);
 178
 179         /* Release resources, unregister device */
 180         ret = mtd_device_unregister(pasemi_nand_mtd);
 181         WARN_ON(ret);
 182         nand_cleanup(chip);
 183
 184         release_region(lpcctl, 4);
 185
 186         iounmap(chip->legacy.IO_ADDR_R);
 187
 188         /* Free the MTD device structure */
 189         kfree(chip);
 190
 191         pasemi_nand_mtd = NULL;
 192
 193         return 0;
 194 }
 195
 196 static const struct of_device_id pasemi_nand_match[] =
 197 {
 198         {
 199                 .compatible   = "pasemi,localbus-nand",
 200         },
 201         {},
 202 };
 203
 204 MODULE_DEVICE_TABLE(of, pasemi_nand_match);
 205
 206 static struct platform_driver pasemi_nand_driver =
 207 {
 208         .driver = {
 209                 .name = driver_name,
 210                 .of_match_table = pasemi_nand_match,
 211         },
 212         .probe          = pasemi_nand_probe,
 213         .remove         = pasemi_nand_remove,
 214 };
 215
 216 module_platform_driver(pasemi_nand_driver);
 217
 218 MODULE_LICENSE("GPL");
 219 MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
 220 MODULE_DESCRIPTION("NAND flash interface driver for PA Semi PWRficient");