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 #ifdef CONFIG_MTD_CMDLINE_PARTS
  25 static const char *part_probes[] = { "cmdlinepart", NULL };
  26 #endif
  27
  28 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  29 {
  30         struct nand_chip *nc = mtd->priv;
  31         struct orion_nand_data *board = nc->priv;
  32         u32 offs;
  33
  34         if (cmd == NAND_CMD_NONE)
  35                 return;
  36
  37         if (ctrl & NAND_CLE)
  38                 offs = (1 << board->cle);
  39         else if (ctrl & NAND_ALE)
  40                 offs = (1 << board->ale);
  41         else
  42                 return;
  43
  44         if (nc->options & NAND_BUSWIDTH_16)
  45                 offs <<= 1;
  46
  47         writeb(cmd, nc->IO_ADDR_W + offs);
  48 }
  49
  50 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
  51 {
  52         struct nand_chip *chip = mtd->priv;
  53         void __iomem *io_base = chip->IO_ADDR_R;
  54         uint64_t *buf64;
  55         int i = 0;
  56
  57         while (len && (unsigned long)buf & 7) {
  58                 *buf++ = readb(io_base);
  59                 len--;
  60         }
  61         buf64 = (uint64_t *)buf;
  62         while (i < len/8) {
  63                 /*
  64                  * Since GCC has no proper constraint (PR 43518)
  65                  * force x variable to r2/r3 registers as ldrd instruction
  66                  * requires first register to be even.
  67                  */
  68                 register uint64_t x asm ("r2");
  69
  70                 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
  71                 buf64[i++] = x;
  72         }
  73         i *= 8;
  74         while (i < len)
  75                 buf[i++] = readb(io_base);
  76 }
  77
  78 static int __init orion_nand_probe(struct platform_device *pdev)
  79 {
  80         struct mtd_info *mtd;
  81         struct nand_chip *nc;
  82         struct orion_nand_data *board;
  83         void __iomem *io_base;
  84         int ret = 0;
  85 #ifdef CONFIG_MTD_PARTITIONS
  86         struct mtd_partition *partitions = NULL;
  87         int num_part = 0;
  88 #endif
  89
  90         nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
  91         if (!nc) {
  92                 printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
  93                 ret = -ENOMEM;
  94                 goto no_res;
  95         }
  96         mtd = (struct mtd_info *)(nc + 1);
  97
  98         io_base = ioremap(pdev->resource[0].start,
  99                         pdev->resource[0].end - pdev->resource[0].start + 1);
 100         if (!io_base) {
 101                 printk(KERN_ERR "orion_nand: ioremap failed\n");
 102                 ret = -EIO;
 103                 goto no_res;
 104         }
 105
 106         board = pdev->dev.platform_data;
 107
 108         mtd->priv = nc;
 109         mtd->owner = THIS_MODULE;
 110
 111         nc->priv = board;
 112         nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
 113         nc->cmd_ctrl = orion_nand_cmd_ctrl;
 114         nc->read_buf = orion_nand_read_buf;
 115         nc->ecc.mode = NAND_ECC_SOFT;
 116
 117         if (board->chip_delay)
 118                 nc->chip_delay = board->chip_delay;
 119
 120         if (board->width == 16)
 121                 nc->options |= NAND_BUSWIDTH_16;
 122
 123         platform_set_drvdata(pdev, mtd);
 124
 125         if (nand_scan(mtd, 1)) {
 126                 ret = -ENXIO;
 127                 goto no_dev;
 128         }
 129
 130 #ifdef CONFIG_MTD_PARTITIONS
 131 #ifdef CONFIG_MTD_CMDLINE_PARTS
 132         mtd->name = "orion_nand";
 133         num_part = parse_mtd_partitions(mtd, part_probes, &partitions, 0);
 134 #endif
 135         /* If cmdline partitions have been passed, let them be used */
 136         if (num_part <= 0) {
 137                 num_part = board->nr_parts;
 138                 partitions = board->parts;
 139         }
 140
 141         if (partitions && num_part > 0)
 142                 ret = add_mtd_partitions(mtd, partitions, num_part);
 143         else
 144                 ret = add_mtd_device(mtd);
 145 #else
 146         ret = add_mtd_device(mtd);
 147 #endif
 148
 149         if (ret) {
 150                 nand_release(mtd);
 151                 goto no_dev;
 152         }
 153
 154         return 0;
 155
 156 no_dev:
 157         platform_set_drvdata(pdev, NULL);
 158         iounmap(io_base);
 159 no_res:
 160         kfree(nc);
 161
 162         return ret;
 163 }
 164
 165 static int __devexit orion_nand_remove(struct platform_device *pdev)
 166 {
 167         struct mtd_info *mtd = platform_get_drvdata(pdev);
 168         struct nand_chip *nc = mtd->priv;
 169
 170         nand_release(mtd);
 171
 172         iounmap(nc->IO_ADDR_W);
 173
 174         kfree(nc);
 175
 176         return 0;
 177 }
 178
 179 static struct platform_driver orion_nand_driver = {
 180         .remove         = __devexit_p(orion_nand_remove),
 181         .driver         = {
 182                 .name   = "orion_nand",
 183                 .owner  = THIS_MODULE,
 184         },
 185 };
 186
 187 static int __init orion_nand_init(void)
 188 {
 189         return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
 190 }
 191
 192 static void __exit orion_nand_exit(void)
 193 {
 194         platform_driver_unregister(&orion_nand_driver);
 195 }
 196
 197 module_init(orion_nand_init);
 198 module_exit(orion_nand_exit);
 199
 200 MODULE_LICENSE("GPL");
 201 MODULE_AUTHOR("Tzachi Perelstein");
 202 MODULE_DESCRIPTION("NAND glue for Orion platforms");
 203 MODULE_ALIAS("platform:orion_nand");