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 <mach/hardware.h>
  25 #include <plat/orion_nand.h>
  26
  27 static void orion_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  28 {
  29         struct nand_chip *nc = mtd->priv;
  30         struct orion_nand_data *board = nc->priv;
  31         u32 offs;
  32
  33         if (cmd == NAND_CMD_NONE)
  34                 return;
  35
  36         if (ctrl & NAND_CLE)
  37                 offs = (1 << board->cle);
  38         else if (ctrl & NAND_ALE)
  39                 offs = (1 << board->ale);
  40         else
  41                 return;
  42
  43         if (nc->options & NAND_BUSWIDTH_16)
  44                 offs <<= 1;
  45
  46         writeb(cmd, nc->IO_ADDR_W + offs);
  47 }
  48
  49 static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
  50 {
  51         struct nand_chip *chip = mtd->priv;
  52         void __iomem *io_base = chip->IO_ADDR_R;
  53         uint64_t *buf64;
  54         int i = 0;
  55
  56         while (len && (unsigned long)buf & 7) {
  57                 *buf++ = readb(io_base);
  58                 len--;
  59         }
  60         buf64 = (uint64_t *)buf;
  61         while (i < len/8) {
  62                 /*
  63                  * Since GCC has no proper constraint (PR 43518)
  64                  * force x variable to r2/r3 registers as ldrd instruction
  65                  * requires first register to be even.
  66                  */
  67                 register uint64_t x asm ("r2");
  68
  69                 asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base));
  70                 buf64[i++] = x;
  71         }
  72         i *= 8;
  73         while (i < len)
  74                 buf[i++] = readb(io_base);
  75 }
  76
  77 static int __init orion_nand_probe(struct platform_device *pdev)
  78 {
  79         struct mtd_info *mtd;
  80         struct mtd_part_parser_data ppdata = {};
  81         struct nand_chip *nc;
  82         struct orion_nand_data *board;
  83         struct resource *res;
  84         struct clk *clk;
  85         void __iomem *io_base;
  86         int ret = 0;
  87         u32 val = 0;
  88
  89         nc = kzalloc(sizeof(struct nand_chip) + sizeof(struct mtd_info), GFP_KERNEL);
  90         if (!nc) {
  91                 printk(KERN_ERR "orion_nand: failed to allocate device structure.\n");
  92                 ret = -ENOMEM;
  93                 goto no_res;
  94         }
  95         mtd = (struct mtd_info *)(nc + 1);
  96
  97         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  98         if (!res) {
  99                 ret = -ENODEV;
 100                 goto no_res;
 101         }
 102
 103         io_base = ioremap(res->start, resource_size(res));
 104         if (!io_base) {
 105                 printk(KERN_ERR "orion_nand: ioremap failed\n");
 106                 ret = -EIO;
 107                 goto no_res;
 108         }
 109
 110         if (pdev->dev.of_node) {
 111                 board = devm_kzalloc(&pdev->dev, sizeof(struct orion_nand_data),
 112                                         GFP_KERNEL);
 113                 if (!board) {
 114                         printk(KERN_ERR "orion_nand: failed to allocate board structure.\n");
 115                         ret = -ENOMEM;
 116                         goto no_res;
 117                 }
 118                 if (!of_property_read_u32(pdev->dev.of_node, "cle", &val))
 119                         board->cle = (u8)val;
 120                 else
 121                         board->cle = 0;
 122                 if (!of_property_read_u32(pdev->dev.of_node, "ale", &val))
 123                         board->ale = (u8)val;
 124                 else
 125                         board->ale = 1;
 126                 if (!of_property_read_u32(pdev->dev.of_node,
 127                                                 "bank-width", &val))
 128                         board->width = (u8)val * 8;
 129                 else
 130                         board->width = 8;
 131                 if (!of_property_read_u32(pdev->dev.of_node,
 132                                                 "chip-delay", &val))
 133                         board->chip_delay = (u8)val;
 134         } else
 135                 board = pdev->dev.platform_data;
 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         platform_set_drvdata(pdev, NULL);
 187         iounmap(io_base);
 188 no_res:
 189         kfree(nc);
 190
 191         return ret;
 192 }
 193
 194 static int __devexit orion_nand_remove(struct platform_device *pdev)
 195 {
 196         struct mtd_info *mtd = platform_get_drvdata(pdev);
 197         struct nand_chip *nc = mtd->priv;
 198         struct clk *clk;
 199
 200         nand_release(mtd);
 201
 202         iounmap(nc->IO_ADDR_W);
 203
 204         kfree(nc);
 205
 206         clk = clk_get(&pdev->dev, NULL);
 207         if (!IS_ERR(clk)) {
 208                 clk_disable_unprepare(clk);
 209                 clk_put(clk);
 210         }
 211
 212         return 0;
 213 }
 214
 215 #ifdef CONFIG_OF
 216 static struct of_device_id orion_nand_of_match_table[] = {
 217         { .compatible = "mrvl,orion-nand", },
 218         {},
 219 };
 220 #endif
 221
 222 static struct platform_driver orion_nand_driver = {
 223         .remove         = __devexit_p(orion_nand_remove),
 224         .driver         = {
 225                 .name   = "orion_nand",
 226                 .owner  = THIS_MODULE,
 227                 .of_match_table = of_match_ptr(orion_nand_of_match_table),
 228         },
 229 };
 230
 231 static int __init orion_nand_init(void)
 232 {
 233         return platform_driver_probe(&orion_nand_driver, orion_nand_probe);
 234 }
 235
 236 static void __exit orion_nand_exit(void)
 237 {
 238         platform_driver_unregister(&orion_nand_driver);
 239 }
 240
 241 module_init(orion_nand_init);
 242 module_exit(orion_nand_exit);
 243
 244 MODULE_LICENSE("GPL");
 245 MODULE_AUTHOR("Tzachi Perelstein");
 246 MODULE_DESCRIPTION("NAND glue for Orion platforms");
 247 MODULE_ALIAS("platform:orion_nand");