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/of.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/nand.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/clk.h>
  21 #include <linux/err.h>
  22 #include <asm/io.h>
  23 #include <asm/sizes.h>
  24 #include <linux/platform_data/mtd-orion_nand.h>
  25
  26 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  27 {
  28         struct nand_chip *nc = mtd->priv;
  29         struct orion_nand_data *board = nc->priv;
  30         u32 offs;
  31
  32         if (cmd == NAND_CMD_NONE)
  33                 return;
  34
  35         if (ctrl & NAND_CLE)
  36                 offs = (1 << board->cle);
  37         else if (ctrl & NAND_ALE)
  38                 offs = (1 << board->ale);
  39         else
  40                 return;
  41
  42         if (nc->options & NAND_BUSWIDTH_16)
  43                 offs <<= 1;
  44
  45         writeb(cmd, nc->IO_ADDR_W + offs);
  46 }
  47
  48 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
  49 {
  50         struct nand_chip *chip = mtd->priv;
  51         void __iomem *io_base = chip->IO_ADDR_R;
  52         uint64_t *buf64;
  53         int i = 0;
  54
  55         while (len && (unsigned long)buf & 7) {
  56                 *buf++ = readb(io_base);
  57                 len--;
  58         }
  59         buf64 = (uint64_t *)buf;
  60         while (i < len/8) {
  61                 /*
  62                  * Since GCC has no proper constraint (PR 43518)
  63                  * force x variable to r2/r3 registers as ldrd instruction
  64                  * requires first register to be even.
  65                  */
  66                 register uint64_t x asm ("r2");
  67
  68                 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
  69                 buf64[i++] = x;
  70         }
  71         i *= 8;
  72         while (i < len)
  73                 buf[i++] = readb(io_base);
  74 }
  75
  76 static int __init orion_nand_probe(struct platform_device *pdev)
  77 {
  78         struct mtd_info *mtd;
  79         struct mtd_part_parser_data ppdata = {};
  80         struct nand_chip *nc;
  81         struct orion_nand_data *board;
  82         struct resource *res;
  83         struct clk *clk;
  84         void __iomem *io_base;
  85         int ret = 0;
  86         u32 val = 0;
  87
  88         nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
  89         if (!nc) {
  90                 printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
  91                 ret = -ENOMEM;
  92                 goto no_res;
  93         }
  94         mtd = (struct mtd_info *)(nc + 1);
  95
  96         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  97         if (!res) {
  98                 ret = -ENODEV;
  99                 goto no_res;
 100         }
 101
 102         io_base = ioremap(res->start, resource_size(res));
 103         if (!io_base) {
 104                 printk(KERN_ERR "orion_nand: ioremap failed\n");
 105                 ret = -EIO;
 106                 goto no_res;
 107         }
 108
 109         if (pdev->dev.of_node) {
 110                 board = devm_kzalloc(&pdev->dev, sizeof(struct orion_nand_data),
 111                                         GFP_KERNEL);
 112                 if (!board) {
 113                         printk(KERN_ERR "orion_nand: failed to allocate board structure.\n");
 114                         ret = -ENOMEM;
 115                         goto no_res;
 116                 }
 117                 if (!of_property_read_u32(pdev->dev.of_node, "cle", &val))
 118                         board->cle = (u8)val;
 119                 else
 120                         board->cle = 0;
 121                 if (!of_property_read_u32(pdev->dev.of_node, "ale", &val))
 122                         board->ale = (u8)val;
 123                 else
 124                         board->ale = 1;
 125                 if (!of_property_read_u32(pdev->dev.of_node,
 126                                                 "bank-width", &val))
 127                         board->width = (u8)val * 8;
 128                 else
 129                         board->width = 8;
 130                 if (!of_property_read_u32(pdev->dev.of_node,
 131                                                 "chip-delay", &val))
 132                         board->chip_delay = (u8)val;
 133         } else {
 134                 board = dev_get_platdata(&pdev->dev);
 135         }
 136
 137         mtd->priv = nc;
 138         mtd->owner = THIS_MODULE;
 139
 140         nc->priv = board;
 141         nc->IO_ADDR_R = nc->IO_ADDR_W = io_base;
 142         nc->cmd_ctrl = orion_nand_cmd_ctrl;
 143         nc->read_buf = orion_nand_read_buf;
 144         nc->ecc.mode = NAND_ECC_SOFT;
 145
 146         if (board->chip_delay)
 147                 nc->chip_delay = board->chip_delay;
 148
 149         WARN(board->width > 16,
 150                 "%d bit bus width out of range",
 151                 board->width);
 152
 153         if (board->width == 16)
 154                 nc->options |= NAND_BUSWIDTH_16;
 155
 156         if (board->dev_ready)
 157                 nc->dev_ready = board->dev_ready;
 158
 159         platform_set_drvdata(pdev, mtd);
 160
 161         /* Not all platforms can gate the clock, so it is not
 162            an error if the clock does not exists. */
 163         clk = clk_get(&pdev->dev, NULL);
 164         if (!IS_ERR(clk)) {
 165                 clk_prepare_enable(clk);
 166                 clk_put(clk);
 167         }
 168
 169         if (nand_scan(mtd, 1)) {
 170                 ret = -ENXIO;
 171                 goto no_dev;
 172         }
 173
 174         mtd->name = "orion_nand";
 175         ppdata.of_node = pdev->dev.of_node;
 176         ret = mtd_device_parse_register(mtd, NULL, &ppdata,
 177                         board->parts, board->nr_parts);
 178         if (ret) {
 179                 nand_release(mtd);
 180                 goto no_dev;
 181         }
 182
 183         return 0;
 184
 185 no_dev:
 186         if (!IS_ERR(clk)) {
 187                 clk_disable_unprepare(clk);
 188                 clk_put(clk);
 189         }
 190         iounmap(io_base);
 191 no_res:
 192         kfree(nc);
 193
 194         return ret;
 195 }
 196
 197 static int orion_nand_remove(struct platform_device *pdev)
 198 {
 199         struct mtd_info *mtd = platform_get_drvdata(pdev);
 200         struct nand_chip *nc = mtd->priv;
 201         struct clk *clk;
 202
 203         nand_release(mtd);
 204
 205         iounmap(nc->IO_ADDR_W);
 206
 207         kfree(nc);
 208
 209         clk = clk_get(&pdev->dev, NULL);
 210         if (!IS_ERR(clk)) {
 211                 clk_disable_unprepare(clk);
 212                 clk_put(clk);
 213         }
 214
 215         return 0;
 216 }
 217
 218 #ifdef CONFIG_OF
 219 static struct of_device_id orion_nand_of_match_table[] = {
 220         { .compatible = "marvell,orion-nand", },
 221         {},
 222 };
 223 #endif
 224
 225 static struct platform_driver orion_nand_driver = {
 226         .remove         = orion_nand_remove,
 227         .driver         = {
 228                 .name   = "orion_nand",
 229                 .owner  = THIS_MODULE,
 230                 .of_match_table = of_match_ptr(orion_nand_of_match_table),
 231         },
 232 };
 233
 234 module_platform_driver_probe(orion_nand_driver, orion_nand_probe);
 235
 236 MODULE_LICENSE("GPL");
 237 MODULE_AUTHOR("Tzachi Perelstein");
 238 MODULE_DESCRIPTION("NAND glue for Orion platforms");
 239 MODULE_ALIAS("platform:orion_nand");