drivers/mtd/nand/raw/cs553x_nand.c

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