drivers/mtd/nand/orion_nand.c

   1 /*
   2  * drivers/mtd/nand/orion_nand.c
   3  *
   4  * NAND support for Marvell Orion SoC platforms
   5  *
   6  * Tzachi Perelstein <tzachi@marvell.com>
   7  *
   8  * This file is licensed under  the terms of the GNU General Public
   9  * License version 2. This program is licensed "as is" without any
  10  * warranty of any kind, whether express or implied.
  11  */
  12
  13 #include <linux/slab.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/mtd/nand.h>
  18 #include <linux/mtd/partitions.h>
  19 #include <asm/io.h>
  20 #include <asm/sizes.h>
  21 #include <mach/hardware.h>
  22 #include <plat/orion_nand.h>
  23
  24 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  25 {
  26         struct nand_chip *nc = mtd->priv;
  27         struct orion_nand_data *board = nc->priv;
  28         u32 offs;
  29
  30         if (cmd == NAND_CMD_NONE)
  31                 return;
  32
  33         if (ctrl & NAND_CLE)
  34                 offs = (1 << board->cle);
  35         else if (ctrl & NAND_ALE)
  36                 offs = (1 << board->ale);
  37         else
  38                 return;
  39
  40         if (nc->options & NAND_BUSWIDTH_16)
  41                 offs <<= 1;
  42
  43         writeb(cmd, nc->IO_ADDR_W + offs);
  44 }
  45
  46 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
  47 {
  48         struct nand_chip *chip = mtd->priv;
  49         void __iomem *io_base = chip->IO_ADDR_R;
  50         uint64_t *buf64;
  51         int i = 0;
  52
  53         while (len && (unsigned long)buf & 7) {
  54                 *buf++ = readb(io_base);
  55                 len--;
  56         }
  57         buf64 = (uint64_t *)buf;
  58         while (i < len/8) {
  59                 /*
  60                  * Since GCC has no proper constraint (PR 43518)
  61                  * force x variable to r2/r3 registers as ldrd instruction
  62                  * requires first register to be even.
  63                  */
  64                 register uint64_t x asm ("r2");
  65
  66                 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
  67                 buf64[i++] = x;
  68         }
  69         i *= 8;
  70         while (i < len)
  71                 buf[i++] = readb(io_base);
  72 }
  73
  74 static int __init orion_nand_probe(struct platform_device *pdev)
  75 {
  76         struct mtd_info *mtd;
  77         struct nand_chip *nc;
  78         struct orion_nand_data *board;
  79         struct resource *res;
  80         void __iomem *io_base;
  81         int ret = 0;
  82
  83         nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
  84         if (!nc) {
  85                 printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
  86                 ret = -ENOMEM;
  87                 goto no_res;
  88         }
  89         mtd = (struct mtd_info *)(nc + 1);
  90
  91         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  92         if (!res) {
  93                 ret = -ENODEV;
  94                 goto no_res;
  95         }
  96
  97         io_base = ioremap(res->start, resource_size(res));
  98         if (!io_base) {
  99                 printk(KERN_ERR "orion_nand: ioremap failed\n");
 100                 ret = -EIO;
 101                 goto no_res;
 102         }
 103
 104         board = pdev->dev.platform_data;
 105
 106         mtd->priv = nc;
 107         mtd->owner = THIS_MODULE;
 108
 109         nc->priv = board;
 110         nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
 111         nc->cmd_ctrl = orion_nand_cmd_ctrl;
 112         nc->read_buf = orion_nand_read_buf;
 113         nc->ecc.mode = NAND_ECC_SOFT;
 114
 115         if (board->chip_delay)
 116                 nc->chip_delay = board->chip_delay;
 117
 118         if (board->width == 16)
 119                 nc->options |= NAND_BUSWIDTH_16;
 120
 121         if (board->dev_ready)
 122                 nc->dev_ready = board->dev_ready;
 123
 124         platform_set_drvdata(pdev, mtd);
 125
 126         if (nand_scan(mtd, 1)) {
 127                 ret = -ENXIO;
 128                 goto no_dev;
 129         }
 130
 131         mtd->name = "orion_nand";
 132         ret = mtd_device_parse_register(mtd, NULL, 0,
 133                         board->parts, board->nr_parts);
 134         if (ret) {
 135                 nand_release(mtd);
 136                 goto no_dev;
 137         }
 138
 139         return 0;
 140
 141 no_dev:
 142         platform_set_drvdata(pdev, NULL);
 143         iounmap(io_base);
 144 no_res:
 145         kfree(nc);
 146
 147         return ret;
 148 }
 149
 150 static int __devexit orion_nand_remove(struct platform_device *pdev)
 151 {
 152         struct mtd_info *mtd = platform_get_drvdata(pdev);
 153         struct nand_chip *nc = mtd->priv;
 154
 155         nand_release(mtd);
 156
 157         iounmap(nc->IO_ADDR_W);
 158
 159         kfree(nc);
 160
 161         return 0;
 162 }
 163
 164 static struct platform_driver orion_nand_driver = {
 165         .remove         = __devexit_p(orion_nand_remove),
 166         .driver         = {
 167                 .name   = "orion_nand",
 168                 .owner  = THIS_MODULE,
 169         },
 170 };
 171
 172 static int __init orion_nand_init(void)
 173 {
 174         return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
 175 }
 176
 177 static void __exit orion_nand_exit(void)
 178 {
 179         platform_driver_unregister(&orion_nand_driver);
 180 }
 181
 182 module_init(orion_nand_init);
 183 module_exit(orion_nand_exit);
 184
 185 MODULE_LICENSE("GPL");
 186 MODULE_AUTHOR("Tzachi Perelstein");
 187 MODULE_DESCRIPTION("NAND glue for Orion platforms");
 188 MODULE_ALIAS("platform:orion_nand");