drivers/mtd/nand/fsl_upm.c

   1 /*
   2  * Freescale UPM NAND driver.
   3  *
   4  * Copyright © 2007-2008  MontaVista Software, Inc.
   5  *
   6  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/delay.h>
  17 #include <linux/mtd/nand.h>
  18 #include <linux/mtd/nand_ecc.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/of_gpio.h>
  23 #include <linux/io.h>
  24 #include <linux/slab.h>
  25 #include <asm/fsl_lbc.h>
  26
  27 #define FSL_UPM_WAIT_RUN_PATTERN  0x1
  28 #define FSL_UPM_WAIT_WRITE_BYTE   0x2
  29 #define FSL_UPM_WAIT_WRITE_BUFFER 0x4
  30
  31 struct fsl_upm_nand {
  32         struct device *dev;
  33         struct mtd_info mtd;
  34         struct nand_chip chip;
  35         int last_ctrl;
  36         struct mtd_partition *parts;
  37         struct fsl_upm upm;
  38         uint8_t upm_addr_offset;
  39         uint8_t upm_cmd_offset;
  40         void __iomem *io_base;
  41         int rnb_gpio[NAND_MAX_CHIPS];
  42         uint32_t mchip_offsets[NAND_MAX_CHIPS];
  43         uint32_t mchip_count;
  44         uint32_t mchip_number;
  45         int chip_delay;
  46         uint32_t wait_flags;
  47 };
  48
  49 static inline struct fsl_upm_nand *to_fsl_upm_nand(struct mtd_info *mtdinfo)
  50 {
  51         return container_of(mtdinfo, struct fsl_upm_nand, mtd);
  52 }
  53
  54 static int fun_chip_ready(struct mtd_info *mtd)
  55 {
  56         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  57
  58         if (gpio_get_value(fun->rnb_gpio[fun->mchip_number]))
  59                 return 1;
  60
  61         dev_vdbg(fun->dev, "busy\n");
  62         return 0;
  63 }
  64
  65 static void fun_wait_rnb(struct fsl_upm_nand *fun)
  66 {
  67         if (fun->rnb_gpio[fun->mchip_number] >= 0) {
  68                 int cnt = 1000000;
  69
  70                 while (--cnt && !fun_chip_ready(&fun->mtd))
  71                         cpu_relax();
  72                 if (!cnt)
  73                         dev_err(fun->dev, "tired waiting for RNB\n");
  74         } else {
  75                 ndelay(100);
  76         }
  77 }
  78
  79 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  80 {
  81         struct nand_chip *chip = mtd->priv;
  82         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  83         u32 mar;
  84
  85         if (!(ctrl & fun->last_ctrl)) {
  86                 fsl_upm_end_pattern(&fun->upm);
  87
  88                 if (cmd == NAND_CMD_NONE)
  89                         return;
  90
  91                 fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
  92         }
  93
  94         if (ctrl & NAND_CTRL_CHANGE) {
  95                 if (ctrl & NAND_ALE)
  96                         fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
  97                 else if (ctrl & NAND_CLE)
  98                         fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
  99         }
 100
 101         mar = (cmd << (32 - fun->upm.width)) |
 102                 fun->mchip_offsets[fun->mchip_number];
 103         fsl_upm_run_pattern(&fun->upm, chip->IO_ADDR_R, mar);
 104
 105         if (fun->wait_flags & FSL_UPM_WAIT_RUN_PATTERN)
 106                 fun_wait_rnb(fun);
 107 }
 108
 109 static void fun_select_chip(struct mtd_info *mtd, int mchip_nr)
 110 {
 111         struct nand_chip *chip = mtd->priv;
 112         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 113
 114         if (mchip_nr == -1) {
 115                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
 116         } else if (mchip_nr >= 0 && mchip_nr < NAND_MAX_CHIPS) {
 117                 fun->mchip_number = mchip_nr;
 118                 chip->IO_ADDR_R = fun->io_base + fun->mchip_offsets[mchip_nr];
 119                 chip->IO_ADDR_W = chip->IO_ADDR_R;
 120         } else {
 121                 BUG();
 122         }
 123 }
 124
 125 static uint8_t fun_read_byte(struct mtd_info *mtd)
 126 {
 127         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 128
 129         return in_8(fun->chip.IO_ADDR_R);
 130 }
 131
 132 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 133 {
 134         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 135         int i;
 136
 137         for (i = 0; i < len; i++)
 138                 buf[i] = in_8(fun->chip.IO_ADDR_R);
 139 }
 140
 141 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 142 {
 143         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 144         int i;
 145
 146         for (i = 0; i < len; i++) {
 147                 out_8(fun->chip.IO_ADDR_W, buf[i]);
 148                 if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BYTE)
 149                         fun_wait_rnb(fun);
 150         }
 151         if (fun->wait_flags & FSL_UPM_WAIT_WRITE_BUFFER)
 152                 fun_wait_rnb(fun);
 153 }
 154
 155 static int fun_chip_init(struct fsl_upm_nand *fun,
 156                          const struct device_node *upm_np,
 157                          const struct resource *io_res)
 158 {
 159         int ret;
 160         struct device_node *flash_np;
 161         struct mtd_part_parser_data ppdata;
 162
 163         fun->chip.IO_ADDR_R = fun->io_base;
 164         fun->chip.IO_ADDR_W = fun->io_base;
 165         fun->chip.cmd_ctrl = fun_cmd_ctrl;
 166         fun->chip.chip_delay = fun->chip_delay;
 167         fun->chip.read_byte = fun_read_byte;
 168         fun->chip.read_buf = fun_read_buf;
 169         fun->chip.write_buf = fun_write_buf;
 170         fun->chip.ecc.mode = NAND_ECC_SOFT;
 171         if (fun->mchip_count > 1)
 172                 fun->chip.select_chip = fun_select_chip;
 173
 174         if (fun->rnb_gpio[0] >= 0)
 175                 fun->chip.dev_ready = fun_chip_ready;
 176
 177         fun->mtd.priv = &fun->chip;
 178         fun->mtd.owner = THIS_MODULE;
 179
 180         flash_np = of_get_next_child(upm_np, NULL);
 181         if (!flash_np)
 182                 return -ENODEV;
 183
 184         fun->mtd.name = kasprintf(GFP_KERNEL, "0x%llx.%s", (u64)io_res->start,
 185                                   flash_np->name);
 186         if (!fun->mtd.name) {
 187                 ret = -ENOMEM;
 188                 goto err;
 189         }
 190
 191         ret = nand_scan(&fun->mtd, fun->mchip_count);
 192         if (ret)
 193                 goto err;
 194
 195         ppdata.of_node = flash_np;
 196         ret = mtd_device_parse_register(&fun->mtd, NULL, &ppdata, NULL, 0);
 197 err:
 198         of_node_put(flash_np);
 199         if (ret)
 200                 kfree(fun->mtd.name);
 201         return ret;
 202 }
 203
 204 static int fun_probe(struct platform_device *ofdev)
 205 {
 206         struct fsl_upm_nand *fun;
 207         struct resource io_res;
 208         const __be32 *prop;
 209         int rnb_gpio;
 210         int ret;
 211         int size;
 212         int i;
 213
 214         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
 215         if (!fun)
 216                 return -ENOMEM;
 217
 218         ret = of_address_to_resource(ofdev->dev.of_node, 0, &io_res);
 219         if (ret) {
 220                 dev_err(&ofdev->dev, "can't get IO base\n");
 221                 goto err1;
 222         }
 223
 224         ret = fsl_upm_find(io_res.start, &fun->upm);
 225         if (ret) {
 226                 dev_err(&ofdev->dev, "can't find UPM\n");
 227                 goto err1;
 228         }
 229
 230         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
 231                                &size);
 232         if (!prop || size != sizeof(uint32_t)) {
 233                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
 234                 ret = -EINVAL;
 235                 goto err1;
 236         }
 237         fun->upm_addr_offset = *prop;
 238
 239         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
 240         if (!prop || size != sizeof(uint32_t)) {
 241                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
 242                 ret = -EINVAL;
 243                 goto err1;
 244         }
 245         fun->upm_cmd_offset = *prop;
 246
 247         prop = of_get_property(ofdev->dev.of_node,
 248                                "fsl,upm-addr-line-cs-offsets", &size);
 249         if (prop && (size / sizeof(uint32_t)) > 0) {
 250                 fun->mchip_count = size / sizeof(uint32_t);
 251                 if (fun->mchip_count >= NAND_MAX_CHIPS) {
 252                         dev_err(&ofdev->dev, "too much multiple chips\n");
 253                         goto err1;
 254                 }
 255                 for (i = 0; i < fun->mchip_count; i++)
 256                         fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
 257         } else {
 258                 fun->mchip_count = 1;
 259         }
 260
 261         for (i = 0; i < fun->mchip_count; i++) {
 262                 fun->rnb_gpio[i] = -1;
 263                 rnb_gpio = of_get_gpio(ofdev->dev.of_node, i);
 264                 if (rnb_gpio >= 0) {
 265                         ret = gpio_request(rnb_gpio, dev_name(&ofdev->dev));
 266                         if (ret) {
 267                                 dev_err(&ofdev->dev,
 268                                         "can't request RNB gpio #%d\n", i);
 269                                 goto err2;
 270                         }
 271                         gpio_direction_input(rnb_gpio);
 272                         fun->rnb_gpio[i] = rnb_gpio;
 273                 } else if (rnb_gpio == -EINVAL) {
 274                         dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
 275                         goto err2;
 276                 }
 277         }
 278
 279         prop = of_get_property(ofdev->dev.of_node, "chip-delay", NULL);
 280         if (prop)
 281                 fun->chip_delay = be32_to_cpup(prop);
 282         else
 283                 fun->chip_delay = 50;
 284
 285         prop = of_get_property(ofdev->dev.of_node, "fsl,upm-wait-flags", &size);
 286         if (prop && size == sizeof(uint32_t))
 287                 fun->wait_flags = be32_to_cpup(prop);
 288         else
 289                 fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
 290                                   FSL_UPM_WAIT_WRITE_BYTE;
 291
 292         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
 293                                             resource_size(&io_res));
 294         if (!fun->io_base) {
 295                 ret = -ENOMEM;
 296                 goto err2;
 297         }
 298
 299         fun->dev = &ofdev->dev;
 300         fun->last_ctrl = NAND_CLE;
 301
 302         ret = fun_chip_init(fun, ofdev->dev.of_node, &io_res);
 303         if (ret)
 304                 goto err2;
 305
 306         dev_set_drvdata(&ofdev->dev, fun);
 307
 308         return 0;
 309 err2:
 310         for (i = 0; i < fun->mchip_count; i++) {
 311                 if (fun->rnb_gpio[i] < 0)
 312                         break;
 313                 gpio_free(fun->rnb_gpio[i]);
 314         }
 315 err1:
 316         kfree(fun);
 317
 318         return ret;
 319 }
 320
 321 static int fun_remove(struct platform_device *ofdev)
 322 {
 323         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
 324         int i;
 325
 326         nand_release(&fun->mtd);
 327         kfree(fun->mtd.name);
 328
 329         for (i = 0; i < fun->mchip_count; i++) {
 330                 if (fun->rnb_gpio[i] < 0)
 331                         break;
 332                 gpio_free(fun->rnb_gpio[i]);
 333         }
 334
 335         kfree(fun);
 336
 337         return 0;
 338 }
 339
 340 static const struct of_device_id of_fun_match[] = {
 341         { .compatible = "fsl,upm-nand" },
 342         {},
 343 };
 344 MODULE_DEVICE_TABLE(of, of_fun_match);
 345
 346 static struct platform_driver of_fun_driver = {
 347         .driver = {
 348                 .name = "fsl,upm-nand",
 349                 .owner = THIS_MODULE,
 350                 .of_match_table = of_fun_match,
 351         },
 352         .probe          = fun_probe,
 353         .remove         = fun_remove,
 354 };
 355
 356 module_platform_driver(of_fun_driver);
 357
 358 MODULE_LICENSE("GPL");
 359 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
 360 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
 361                    "LocalBus User-Programmable Machine");