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