LXR linux/drivers/mtd/nand/cs553x

   1/*
   2 * drivers/mtd/nand/cs553x_nand.c
   3 *
   4 * (C) 2005, 2006 Red Hat Inc.
   5 *
   6 * Author: David Woodhouse <dwmw2@infradead.org>
   7 *         Tom Sylla <tom.sylla@amd.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 *
  13 *  Overview:
  14 *   This is a device driver for the NAND flash controller found on
  15 *   the AMD CS5535/CS5536 companion chipsets for the Geode processor.
  16 *   mtd-id for command line partitioning is cs553x_nand_cs[0-3]
  17 *   where 0-3 reflects the chip select for NAND.
  18 *
  19 */
  20
  21#include <linux/kernel.h>
  22#include <linux/slab.h>
  23#include <linux/init.h>
  24#include <linux/module.h>
  25#include <linux/delay.h>
  26#include <linux/mtd/mtd.h>
  27#include <linux/mtd/nand.h>
  28#include <linux/mtd/nand_ecc.h>
  29#include <linux/mtd/partitions.h>
  30
  31#include <asm/msr.h>
  32#include <asm/io.h>
  33
  34#define NR_CS553X_CONTROLLERS   4
  35
  36#define MSR_DIVIL_GLD_CAP       0x51400000      /* DIVIL capabilitiies */
  37#define CAP_CS5535              0x2df000ULL
  38#define CAP_CS5536              0x5df500ULL
  39
  40/* NAND Timing MSRs */
  41#define MSR_NANDF_DATA          0x5140001b      /* NAND Flash Data Timing MSR */
  42#define MSR_NANDF_CTL           0x5140001c      /* NAND Flash Control Timing */
  43#define MSR_NANDF_RSVD          0x5140001d      /* Reserved */
  44
  45/* NAND BAR MSRs */
  46#define MSR_DIVIL_LBAR_FLSH0    0x51400010      /* Flash Chip Select 0 */
  47#define MSR_DIVIL_LBAR_FLSH1    0x51400011      /* Flash Chip Select 1 */
  48#define MSR_DIVIL_LBAR_FLSH2    0x51400012      /* Flash Chip Select 2 */
  49#define MSR_DIVIL_LBAR_FLSH3    0x51400013      /* Flash Chip Select 3 */
  50        /* Each made up of... */
  51#define FLSH_LBAR_EN            (1ULL<<32)
  52#define FLSH_NOR_NAND           (1ULL<<33)      /* 1 for NAND */
  53#define FLSH_MEM_IO             (1ULL<<34)      /* 1 for MMIO */
  54        /* I/O BARs have BASE_ADDR in bits 15:4, IO_MASK in 47:36 */
  55        /* MMIO BARs have BASE_ADDR in bits 31:12, MEM_MASK in 63:44 */
  56
  57/* Pin function selection MSR (IDE vs. flash on the IDE pins) */
  58#define MSR_DIVIL_BALL_OPTS     0x51400015
  59#define PIN_OPT_IDE             (1<<0)  /* 0 for flash, 1 for IDE */
  60
  61/* Registers within the NAND flash controller BAR -- memory mapped */
  62#define MM_NAND_DATA            0x00    /* 0 to 0x7ff, in fact */
  63#define MM_NAND_CTL             0x800   /* Any even address 0x800-0x80e */
  64#define MM_NAND_IO              0x801   /* Any odd address 0x801-0x80f */
  65#define MM_NAND_STS             0x810
  66#define MM_NAND_ECC_LSB         0x811
  67#define MM_NAND_ECC_MSB         0x812
  68#define MM_NAND_ECC_COL         0x813
  69#define MM_NAND_LAC             0x814
  70#define MM_NAND_ECC_CTL         0x815
  71
  72/* Registers within the NAND flash controller BAR -- I/O mapped */
  73#define IO_NAND_DATA            0x00    /* 0 to 3, in fact */
  74#define IO_NAND_CTL             0x04
  75#define IO_NAND_IO              0x05
  76#define IO_NAND_STS             0x06
  77#define IO_NAND_ECC_CTL         0x08
  78#define IO_NAND_ECC_LSB         0x09
  79#define IO_NAND_ECC_MSB         0x0a
  80#define IO_NAND_ECC_COL         0x0b
  81#define IO_NAND_LAC             0x0c
  82
  83#define CS_NAND_CTL_DIST_EN     (1<<4)  /* Enable NAND Distract interrupt */
  84#define CS_NAND_CTL_RDY_INT_MASK        (1<<3)  /* Enable RDY/BUSY# interrupt */
  85#define CS_NAND_CTL_ALE         (1<<2)
  86#define CS_NAND_CTL_CLE         (1<<1)
  87#define CS_NAND_CTL_CE          (1<<0)  /* Keep low; 1 to reset */
  88
  89#define CS_NAND_STS_FLASH_RDY   (1<<3)
  90#define CS_NAND_CTLR_BUSY       (1<<2)
  91#define CS_NAND_CMD_COMP        (1<<1)
  92#define CS_NAND_DIST_ST         (1<<0)
  93
  94#define CS_NAND_ECC_PARITY      (1<<2)
  95#define CS_NAND_ECC_CLRECC      (1<<1)
  96#define CS_NAND_ECC_ENECC       (1<<0)
  97
  98static void cs553x_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  99{
 100        struct nand_chip *this = mtd->priv;
 101
 102        while (unlikely(len > 0x800)) {
 103                memcpy_fromio(buf, this->IO_ADDR_R, 0x800);
 104                buf += 0x800;
 105                len -= 0x800;
 106        }
 107        memcpy_fromio(buf, this->IO_ADDR_R, len);
 108}
 109
 110static void cs553x_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
 111{
 112        struct nand_chip *this = mtd->priv;
 113
 114        while (unlikely(len > 0x800)) {
 115                memcpy_toio(this->IO_ADDR_R, buf, 0x800);
 116                buf += 0x800;
 117                len -= 0x800;
 118        }
 119        memcpy_toio(this->IO_ADDR_R, buf, len);
 120}
 121
 122static unsigned char cs553x_read_byte(struct mtd_info *mtd)
 123{
 124        struct nand_chip *this = mtd->priv;
 125        return readb(this->IO_ADDR_R);
 126}
 127
 128static void cs553x_write_byte(struct mtd_info *mtd, u_char byte)
 129{
 130        struct nand_chip *this = mtd->priv;
 131        int i = 100000;
 132
 133        while (i && readb(this->IO_ADDR_R + MM_NAND_STS) & CS_NAND_CTLR_BUSY) {
 134                udelay(1);
 135                i--;
 136        }
 137        writeb(byte, this->IO_ADDR_W + 0x801);
 138}
 139
 140static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd,
 141                             unsigned int ctrl)
 142{
 143        struct nand_chip *this = mtd->priv;
 144        void __iomem *mmio_base = this->IO_ADDR_R;
 145        if (ctrl & NAND_CTRL_CHANGE) {
 146                unsigned char ctl = (ctrl & ~NAND_CTRL_CHANGE ) ^ 0x01;
 147                writeb(ctl, mmio_base + MM_NAND_CTL);
 148        }
 149        if (cmd != NAND_CMD_NONE)
 150                cs553x_write_byte(mtd, cmd);
 151}
 152
 153static int cs553x_device_ready(struct mtd_info *mtd)
 154{
 155        struct nand_chip *this = mtd->priv;
 156        void __iomem *mmio_base = this->IO_ADDR_R;
 157        unsigned char foo = readb(mmio_base + MM_NAND_STS);
 158
 159        return (foo & CS_NAND_STS_FLASH_RDY) && !(foo & CS_NAND_CTLR_BUSY);
 160}
 161
 162static void cs_enable_hwecc(struct mtd_info *mtd, int mode)
 163{
 164        struct nand_chip *this = mtd->priv;
 165        void __iomem *mmio_base = this->IO_ADDR_R;
 166
 167        writeb(0x07, mmio_base + MM_NAND_ECC_CTL);
 168}
 169
 170static int cs_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code)
 171{
 172        uint32_t ecc;
 173        struct nand_chip *this = mtd->priv;
 174        void __iomem *mmio_base = this->IO_ADDR_R;
 175
 176        ecc = readl(mmio_base + MM_NAND_STS);
 177
 178        ecc_code[1] = ecc >> 8;
 179        ecc_code[0] = ecc >> 16;
 180        ecc_code[2] = ecc >> 24;
 181        return 0;
 182}
 183
 184static struct mtd_info *cs553x_mtd[4];
 185
 186static int __init cs553x_init_one(int cs, int mmio, unsigned long adr)
 187{
 188        int err = 0;
 189        struct nand_chip *this;
 190        struct mtd_info *new_mtd;
 191
 192        printk(KERN_NOTICE "Probing CS553x NAND controller CS#%d at %sIO 0x%08lx\n", cs, mmio?"MM":"P", adr);
 193
 194        if (!mmio) {
 195                printk(KERN_NOTICE "PIO mode not yet implemented for CS553X NAND controller\n");
 196                return -ENXIO;
 197        }
 198
 199        /* Allocate memory for MTD device structure and private data */
 200        new_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
 201        if (!new_mtd) {
 202                printk(KERN_WARNING "Unable to allocate CS553X NAND MTD device structure.\n");
 203                err = -ENOMEM;
 204                goto out;
 205        }
 206
 207        /* Get pointer to private data */
 208        this = (struct nand_chip *)(&new_mtd[1]);
 209
 210        /* Initialize structures */
 211        memset(new_mtd, 0, sizeof(struct mtd_info));
 212        memset(this, 0, sizeof(struct nand_chip));
 213
 214        /* Link the private data with the MTD structure */
 215        new_mtd->priv = this;
 216        new_mtd->owner = THIS_MODULE;
 217
 218        /* map physical address */
 219        this->IO_ADDR_R = this->IO_ADDR_W = ioremap(adr, 4096);
 220        if (!this->IO_ADDR_R) {
 221                printk(KERN_WARNING "ioremap cs553x NAND @0x%08lx failed\n", adr);
 222                err = -EIO;
 223                goto out_mtd;
 224        }
 225
 226        this->cmd_ctrl = cs553x_hwcontrol;
 227        this->dev_ready = cs553x_device_ready;
 228        this->read_byte = cs553x_read_byte;
 229        this->read_buf = cs553x_read_buf;
 230        this->write_buf = cs553x_write_buf;
 231
 232        this->chip_delay = 0;
 233
 234        this->ecc.mode = NAND_ECC_HW;
 235        this->ecc.size = 256;
 236        this->ecc.bytes = 3;
 237        this->ecc.hwctl  = cs_enable_hwecc;
 238        this->ecc.calculate = cs_calculate_ecc;
 239        this->ecc.correct  = nand_correct_data;
 240        this->ecc.strength = 1;
 241
 242        /* Enable the following for a flash based bad block table */
 243        this->bbt_options = NAND_BBT_USE_FLASH;
 244
 245        /* Scan to find existence of the device */
 246        if (nand_scan(new_mtd, 1)) {
 247                err = -ENXIO;
 248                goto out_ior;
 249        }
 250
 251        new_mtd->name = kasprintf(GFP_KERNEL, "cs553x_nand_cs%d", cs);
 252
 253        cs553x_mtd[cs] = new_mtd;
 254        goto out;
 255
 256out_ior:
 257        iounmap(this->IO_ADDR_R);
 258out_mtd:
 259        kfree(new_mtd);
 260out:
 261        return err;
 262}
 263
 264static int is_geode(void)
 265{
 266        /* These are the CPUs which will have a CS553[56] companion chip */
 267        if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 268            boot_cpu_data.x86 == 5 &&
 269            boot_cpu_data.x86_model == 10)
 270                return 1; /* Geode LX */
 271
 272        if ((boot_cpu_data.x86_vendor == X86_VENDOR_NSC ||
 273             boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX) &&
 274            boot_cpu_data.x86 == 5 &&
 275            boot_cpu_data.x86_model == 5)
 276                return 1; /* Geode GX (née GX2) */
 277
 278        return 0;
 279}
 280
 281static int __init cs553x_init(void)
 282{
 283        int err = -ENXIO;
 284        int i;
 285        uint64_t val;
 286
 287        /* If the CPU isn't a Geode GX or LX, abort */
 288        if (!is_geode())
 289                return -ENXIO;
 290
 291        /* If it doesn't have the CS553[56], abort */
 292        rdmsrl(MSR_DIVIL_GLD_CAP, val);
 293        val &= ~0xFFULL;
 294        if (val != CAP_CS5535 && val != CAP_CS5536)
 295                return -ENXIO;
 296
 297        /* If it doesn't have the NAND controller enabled, abort */
 298        rdmsrl(MSR_DIVIL_BALL_OPTS, val);
 299        if (val & PIN_OPT_IDE) {
 300                printk(KERN_INFO "CS553x NAND controller: Flash I/O not enabled in MSR_DIVIL_BALL_OPTS.\n");
 301                return -ENXIO;
 302        }
 303
 304        for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 305                rdmsrl(MSR_DIVIL_LBAR_FLSH0 + i, val);
 306
 307                if ((val & (FLSH_LBAR_EN|FLSH_NOR_NAND)) == (FLSH_LBAR_EN|FLSH_NOR_NAND))
 308                        err = cs553x_init_one(i, !!(val & FLSH_MEM_IO), val & 0xFFFFFFFF);
 309        }
 310
 311        /* Register all devices together here. This means we can easily hack it to
 312           do mtdconcat etc. if we want to. */
 313        for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 314                if (cs553x_mtd[i]) {
 315                        /* If any devices registered, return success. Else the last error. */
 316                        mtd_device_parse_register(cs553x_mtd[i], NULL, NULL,
 317                                                  NULL, 0);
 318                        err = 0;
 319                }
 320        }
 321
 322        return err;
 323}
 324
 325module_init(cs553x_init);
 326
 327static void __exit cs553x_cleanup(void)
 328{
 329        int i;
 330
 331        for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 332                struct mtd_info *mtd = cs553x_mtd[i];
 333                struct nand_chip *this;
 334                void __iomem *mmio_base;
 335
 336                if (!mtd)
 337                        continue;
 338
 339                this = cs553x_mtd[i]->priv;
 340                mmio_base = this->IO_ADDR_R;
 341
 342                /* Release resources, unregister device */
 343                nand_release(cs553x_mtd[i]);
 344                kfree(cs553x_mtd[i]->name);
 345                cs553x_mtd[i] = NULL;
 346
 347                /* unmap physical address */
 348                iounmap(mmio_base);
 349
 350                /* Free the MTD device structure */
 351                kfree(mtd);
 352        }
 353}
 354
 355module_exit(cs553x_cleanup);
 356
 357MODULE_LICENSE("GPL");
 358MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 359MODULE_DESCRIPTION("NAND controller driver for AMD CS5535/CS5536 companion chip");
 360