drivers/mtd/nand/cs553x_nand.c

   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
  98 static void cs553x_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  99 {
 100         struct nand_chip *this = mtd_to_nand(mtd);
 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
 110 static void cs553x_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
 111 {
 112         struct nand_chip *this = mtd_to_nand(mtd);
 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
 122 static unsigned char cs553x_read_byte(struct mtd_info *mtd)
 123 {
 124         struct nand_chip *this = mtd_to_nand(mtd);
 125         return readb(this->IO_ADDR_R);
 126 }
 127
 128 static void cs553x_write_byte(struct mtd_info *mtd, u_char byte)
 129 {
 130         struct nand_chip *this = mtd_to_nand(mtd);
 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
 140 static void cs553x_hwcontrol(struct mtd_info *mtd, int cmd,
 141                              unsigned int ctrl)
 142 {
 143         struct nand_chip *this = mtd_to_nand(mtd);
 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
 153 static int cs553x_device_ready(struct mtd_info *mtd)
 154 {
 155         struct nand_chip *this = mtd_to_nand(mtd);
 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
 162 static void cs_enable_hwecc(struct mtd_info *mtd, int mode)
 163 {
 164         struct nand_chip *this = mtd_to_nand(mtd);
 165         void __iomem *mmio_base = this->IO_ADDR_R;
 166
 167         writeb(0x07, mmio_base + MM_NAND_ECC_CTL);
 168 }
 169
 170 static 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_to_nand(mtd);
 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
 184 static struct mtd_info *cs553x_mtd[4];
 185
 186 static 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         this = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
 201         if (!this) {
 202                 err = -ENOMEM;
 203                 goto out;
 204         }
 205
 206         new_mtd = nand_to_mtd(this);
 207
 208         /* Link the private data with the MTD structure */
 209         new_mtd->owner = THIS_MODULE;
 210
 211         /* map physical address */
 212         this->IO_ADDR_R = this->IO_ADDR_W = ioremap(adr, 4096);
 213         if (!this->IO_ADDR_R) {
 214                 printk(KERN_WARNING "ioremap cs553x NAND @0x%08lx failed\n", adr);
 215                 err = -EIO;
 216                 goto out_mtd;
 217         }
 218
 219         this->cmd_ctrl = cs553x_hwcontrol;
 220         this->dev_ready = cs553x_device_ready;
 221         this->read_byte = cs553x_read_byte;
 222         this->read_buf = cs553x_read_buf;
 223         this->write_buf = cs553x_write_buf;
 224
 225         this->chip_delay = 0;
 226
 227         this->ecc.mode = NAND_ECC_HW;
 228         this->ecc.size = 256;
 229         this->ecc.bytes = 3;
 230         this->ecc.hwctl  = cs_enable_hwecc;
 231         this->ecc.calculate = cs_calculate_ecc;
 232         this->ecc.correct  = nand_correct_data;
 233         this->ecc.strength = 1;
 234
 235         /* Enable the following for a flash based bad block table */
 236         this->bbt_options = NAND_BBT_USE_FLASH;
 237
 238         new_mtd->name = kasprintf(GFP_KERNEL, "cs553x_nand_cs%d", cs);
 239         if (!new_mtd->name) {
 240                 err = -ENOMEM;
 241                 goto out_ior;
 242         }
 243
 244         /* Scan to find existence of the device */
 245         if (nand_scan(new_mtd, 1)) {
 246                 err = -ENXIO;
 247                 goto out_free;
 248         }
 249
 250         cs553x_mtd[cs] = new_mtd;
 251         goto out;
 252
 253 out_free:
 254         kfree(new_mtd->name);
 255 out_ior:
 256         iounmap(this->IO_ADDR_R);
 257 out_mtd:
 258         kfree(this);
 259 out:
 260         return err;
 261 }
 262
 263 static int is_geode(void)
 264 {
 265         /* These are the CPUs which will have a CS553[56] companion chip */
 266         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 267             boot_cpu_data.x86 == 5 &&
 268             boot_cpu_data.x86_model == 10)
 269                 return 1; /* Geode LX */
 270
 271         if ((boot_cpu_data.x86_vendor == X86_VENDOR_NSC ||
 272              boot_cpu_data.x86_vendor == X86_VENDOR_CYRIX) &&
 273             boot_cpu_data.x86 == 5 &&
 274             boot_cpu_data.x86_model == 5)
 275                 return 1; /* Geode GX (née GX2) */
 276
 277         return 0;
 278 }
 279
 280 static int __init cs553x_init(void)
 281 {
 282         int err = -ENXIO;
 283         int i;
 284         uint64_t val;
 285
 286         /* If the CPU isn't a Geode GX or LX, abort */
 287         if (!is_geode())
 288                 return -ENXIO;
 289
 290         /* If it doesn't have the CS553[56], abort */
 291         rdmsrl(MSR_DIVIL_GLD_CAP, val);
 292         val &= ~0xFFULL;
 293         if (val != CAP_CS5535 && val != CAP_CS5536)
 294                 return -ENXIO;
 295
 296         /* If it doesn't have the NAND controller enabled, abort */
 297         rdmsrl(MSR_DIVIL_BALL_OPTS, val);
 298         if (val & PIN_OPT_IDE) {
 299                 printk(KERN_INFO "CS553x NAND controller: Flash I/O not enabled in MSR_DIVIL_BALL_OPTS.\n");
 300                 return -ENXIO;
 301         }
 302
 303         for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 304                 rdmsrl(MSR_DIVIL_LBAR_FLSH0 + i, val);
 305
 306                 if ((val & (FLSH_LBAR_EN|FLSH_NOR_NAND)) == (FLSH_LBAR_EN|FLSH_NOR_NAND))
 307                         err = cs553x_init_one(i, !!(val & FLSH_MEM_IO), val & 0xFFFFFFFF);
 308         }
 309
 310         /* Register all devices together here. This means we can easily hack it to
 311            do mtdconcat etc. if we want to. */
 312         for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 313                 if (cs553x_mtd[i]) {
 314                         /* If any devices registered, return success. Else the last error. */
 315                         mtd_device_parse_register(cs553x_mtd[i], NULL, NULL,
 316                                                   NULL, 0);
 317                         err = 0;
 318                 }
 319         }
 320
 321         return err;
 322 }
 323
 324 module_init(cs553x_init);
 325
 326 static void __exit cs553x_cleanup(void)
 327 {
 328         int i;
 329
 330         for (i = 0; i < NR_CS553X_CONTROLLERS; i++) {
 331                 struct mtd_info *mtd = cs553x_mtd[i];
 332                 struct nand_chip *this;
 333                 void __iomem *mmio_base;
 334
 335                 if (!mtd)
 336                         continue;
 337
 338                 this = mtd_to_nand(mtd);
 339                 mmio_base = this->IO_ADDR_R;
 340
 341                 /* Release resources, unregister device */
 342                 nand_release(mtd);
 343                 kfree(mtd->name);
 344                 cs553x_mtd[i] = NULL;
 345
 346                 /* unmap physical address */
 347                 iounmap(mmio_base);
 348
 349                 /* Free the MTD device structure */
 350                 kfree(this);
 351         }
 352 }
 353
 354 module_exit(cs553x_cleanup);
 355
 356 MODULE_LICENSE("GPL");
 357 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 358 MODULE_DESCRIPTION("NAND controller driver for AMD CS5535/CS5536 companion chip");