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         struct resource *res;
  84         void __iomem *io_base;
  85         int ret = 0;
  86 #ifdef CONFIG_MTD_PARTITIONS
  87         struct mtd_partition *partitions = NULL;
  88         int num_part = 0;
  89 #endif
  90
  91         nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
  92         if (!nc) {
  93                 printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
  94                 ret = -ENOMEM;
  95                 goto no_res;
  96         }
  97         mtd = (struct mtd_info *)(nc + 1);
  98
  99         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 100         if (!res) {
 101                 ret = -ENODEV;
 102                 goto no_res;
 103         }
 104
 105         io_base = ioremap(res->start, resource_size(res));
 106         if (!io_base) {
 107                 printk(KERN_ERR "orion_nand: ioremap failed\n");
 108                 ret = -EIO;
 109                 goto no_res;
 110         }
 111
 112         board = pdev->dev.platform_data;
 113
 114         mtd->priv = nc;
 115         mtd->owner = THIS_MODULE;
 116
 117         nc->priv = board;
 118         nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
 119         nc->cmd_ctrl = orion_nand_cmd_ctrl;
 120         nc->read_buf = orion_nand_read_buf;
 121         nc->ecc.mode = NAND_ECC_SOFT;
 122
 123         if (board->chip_delay)
 124                 nc->chip_delay = board->chip_delay;
 125
 126         if (board->width == 16)
 127                 nc->options |= NAND_BUSWIDTH_16;
 128
 129         if (board->dev_ready)
 130                 nc->dev_ready = board->dev_ready;
 131
 132         platform_set_drvdata(pdev, mtd);
 133
 134         if (nand_scan(mtd, 1)) {
 135                 ret = -ENXIO;
 136                 goto no_dev;
 137         }
 138
 139 #ifdef CONFIG_MTD_PARTITIONS
 140 #ifdef CONFIG_MTD_CMDLINE_PARTS
 141         mtd->name = "orion_nand";
 142         num_part = parse_mtd_partitions(mtd, part_probes, &partitions, 0);
 143 #endif
 144         /* If cmdline partitions have been passed, let them be used */
 145         if (num_part <= 0) {
 146                 num_part = board->nr_parts;
 147                 partitions = board->parts;
 148         }
 149
 150         if (partitions && num_part > 0)
 151                 ret = add_mtd_partitions(mtd, partitions, num_part);
 152         else
 153                 ret = add_mtd_device(mtd);
 154 #else
 155         ret = add_mtd_device(mtd);
 156 #endif
 157
 158         if (ret) {
 159                 nand_release(mtd);
 160                 goto no_dev;
 161         }
 162
 163         return 0;
 164
 165 no_dev:
 166         platform_set_drvdata(pdev, NULL);
 167         iounmap(io_base);
 168 no_res:
 169         kfree(nc);
 170
 171         return ret;
 172 }
 173
 174 static int __devexit orion_nand_remove(struct platform_device *pdev)
 175 {
 176         struct mtd_info *mtd = platform_get_drvdata(pdev);
 177         struct nand_chip *nc = mtd->priv;
 178
 179         nand_release(mtd);
 180
 181         iounmap(nc->IO_ADDR_W);
 182
 183         kfree(nc);
 184
 185         return 0;
 186 }
 187
 188 static struct platform_driver orion_nand_driver = {
 189         .remove         = __devexit_p(orion_nand_remove),
 190         .driver         = {
 191                 .name   = "orion_nand",
 192                 .owner  = THIS_MODULE,
 193         },
 194 };
 195
 196 static int __init orion_nand_init(void)
 197 {
 198         return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
 199 }
 200
 201 static void __exit orion_nand_exit(void)
 202 {
 203         platform_driver_unregister(&orion_nand_driver);
 204 }
 205
 206 module_init(orion_nand_init);
 207 module_exit(orion_nand_exit);
 208
 209 MODULE_LICENSE("GPL");
 210 MODULE_AUTHOR("Tzachi Perelstein");
 211 MODULE_DESCRIPTION("NAND glue for Orion platforms");
 212 MODULE_ALIAS("platform:orion_nand");