linux/drivers/mtd/nand/fsl_upm.c
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   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_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
  32struct 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
  49static 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
  55static 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
  66static 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
  81static 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
 111static 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
 127static 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
 134static 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
 143static 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
 157static 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        fun->chip.ecc.algo = NAND_ECC_HAMMING;
 174        if (fun->mchip_count > 1)
 175                fun->chip.select_chip = fun_select_chip;
 176
 177        if (fun->rnb_gpio[0] >= 0)
 178                fun->chip.dev_ready = fun_chip_ready;
 179
 180        mtd->dev.parent = fun->dev;
 181
 182        flash_np = of_get_next_child(upm_np, NULL);
 183        if (!flash_np)
 184                return -ENODEV;
 185
 186        nand_set_flash_node(&fun->chip, flash_np);
 187        mtd->name = kasprintf(GFP_KERNEL, "0x%llx.%s", (u64)io_res->start,
 188                              flash_np->name);
 189        if (!mtd->name) {
 190                ret = -ENOMEM;
 191                goto err;
 192        }
 193
 194        ret = nand_scan(mtd, fun->mchip_count);
 195        if (ret)
 196                goto err;
 197
 198        ret = mtd_device_register(mtd, NULL, 0);
 199err:
 200        of_node_put(flash_np);
 201        if (ret)
 202                kfree(mtd->name);
 203        return ret;
 204}
 205
 206static int fun_probe(struct platform_device *ofdev)
 207{
 208        struct fsl_upm_nand *fun;
 209        struct resource io_res;
 210        const __be32 *prop;
 211        int rnb_gpio;
 212        int ret;
 213        int size;
 214        int i;
 215
 216        fun = kzalloc(sizeof(*fun), GFP_KERNEL);
 217        if (!fun)
 218                return -ENOMEM;
 219
 220        ret = of_address_to_resource(ofdev->dev.of_node, 0, &io_res);
 221        if (ret) {
 222                dev_err(&ofdev->dev, "can't get IO base\n");
 223                goto err1;
 224        }
 225
 226        ret = fsl_upm_find(io_res.start, &fun->upm);
 227        if (ret) {
 228                dev_err(&ofdev->dev, "can't find UPM\n");
 229                goto err1;
 230        }
 231
 232        prop = of_get_property(ofdev->dev.of_node, "fsl,upm-addr-offset",
 233                               &size);
 234        if (!prop || size != sizeof(uint32_t)) {
 235                dev_err(&ofdev->dev, "can't get UPM address offset\n");
 236                ret = -EINVAL;
 237                goto err1;
 238        }
 239        fun->upm_addr_offset = *prop;
 240
 241        prop = of_get_property(ofdev->dev.of_node, "fsl,upm-cmd-offset", &size);
 242        if (!prop || size != sizeof(uint32_t)) {
 243                dev_err(&ofdev->dev, "can't get UPM command offset\n");
 244                ret = -EINVAL;
 245                goto err1;
 246        }
 247        fun->upm_cmd_offset = *prop;
 248
 249        prop = of_get_property(ofdev->dev.of_node,
 250                               "fsl,upm-addr-line-cs-offsets", &size);
 251        if (prop && (size / sizeof(uint32_t)) > 0) {
 252                fun->mchip_count = size / sizeof(uint32_t);
 253                if (fun->mchip_count >= NAND_MAX_CHIPS) {
 254                        dev_err(&ofdev->dev, "too much multiple chips\n");
 255                        goto err1;
 256                }
 257                for (i = 0; i < fun->mchip_count; i++)
 258                        fun->mchip_offsets[i] = be32_to_cpu(prop[i]);
 259        } else {
 260                fun->mchip_count = 1;
 261        }
 262
 263        for (i = 0; i < fun->mchip_count; i++) {
 264                fun->rnb_gpio[i] = -1;
 265                rnb_gpio = of_get_gpio(ofdev->dev.of_node, i);
 266                if (rnb_gpio >= 0) {
 267                        ret = gpio_request(rnb_gpio, dev_name(&ofdev->dev));
 268                        if (ret) {
 269                                dev_err(&ofdev->dev,
 270                                        "can't request RNB gpio #%d\n", i);
 271                                goto err2;
 272                        }
 273                        gpio_direction_input(rnb_gpio);
 274                        fun->rnb_gpio[i] = rnb_gpio;
 275                } else if (rnb_gpio == -EINVAL) {
 276                        dev_err(&ofdev->dev, "RNB gpio #%d is invalid\n", i);
 277                        goto err2;
 278                }
 279        }
 280
 281        prop = of_get_property(ofdev->dev.of_node, "chip-delay", NULL);
 282        if (prop)
 283                fun->chip_delay = be32_to_cpup(prop);
 284        else
 285                fun->chip_delay = 50;
 286
 287        prop = of_get_property(ofdev->dev.of_node, "fsl,upm-wait-flags", &size);
 288        if (prop && size == sizeof(uint32_t))
 289                fun->wait_flags = be32_to_cpup(prop);
 290        else
 291                fun->wait_flags = FSL_UPM_WAIT_RUN_PATTERN |
 292                                  FSL_UPM_WAIT_WRITE_BYTE;
 293
 294        fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
 295                                            resource_size(&io_res));
 296        if (!fun->io_base) {
 297                ret = -ENOMEM;
 298                goto err2;
 299        }
 300
 301        fun->dev = &ofdev->dev;
 302        fun->last_ctrl = NAND_CLE;
 303
 304        ret = fun_chip_init(fun, ofdev->dev.of_node, &io_res);
 305        if (ret)
 306                goto err2;
 307
 308        dev_set_drvdata(&ofdev->dev, fun);
 309
 310        return 0;
 311err2:
 312        for (i = 0; i < fun->mchip_count; i++) {
 313                if (fun->rnb_gpio[i] < 0)
 314                        break;
 315                gpio_free(fun->rnb_gpio[i]);
 316        }
 317err1:
 318        kfree(fun);
 319
 320        return ret;
 321}
 322
 323static int fun_remove(struct platform_device *ofdev)
 324{
 325        struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
 326        struct mtd_info *mtd = nand_to_mtd(&fun->chip);
 327        int i;
 328
 329        nand_release(mtd);
 330        kfree(mtd->name);
 331
 332        for (i = 0; i < fun->mchip_count; i++) {
 333                if (fun->rnb_gpio[i] < 0)
 334                        break;
 335                gpio_free(fun->rnb_gpio[i]);
 336        }
 337
 338        kfree(fun);
 339
 340        return 0;
 341}
 342
 343static const struct of_device_id of_fun_match[] = {
 344        { .compatible = "fsl,upm-nand" },
 345        {},
 346};
 347MODULE_DEVICE_TABLE(of, of_fun_match);
 348
 349static struct platform_driver of_fun_driver = {
 350        .driver = {
 351                .name = "fsl,upm-nand",
 352                .of_match_table = of_fun_match,
 353        },
 354        .probe          = fun_probe,
 355        .remove         = fun_remove,
 356};
 357
 358module_platform_driver(of_fun_driver);
 359
 360MODULE_LICENSE("GPL");
 361MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
 362MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
 363                   "LocalBus User-Programmable Machine");
 364