drivers/block/systemace.c

   1 /*
   2  * Copyright (c) 2004 Picture Elements, Inc.
   3  *    Stephen Williams (XXXXXXXXXXXXXXXX)
   4  *
   5  *    This source code is free software; you can redistribute it
   6  *    and/or modify it in source code form under the terms of the GNU
   7  *    General Public License as published by the Free Software
   8  *    Foundation; either version 2 of the License, or (at your option)
   9  *    any later version.
  10  *
  11  *    This program is distributed in the hope that it will be useful,
  12  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *    GNU General Public License for more details.
  15  *
  16  *    You should have received a copy of the GNU General Public License
  17  *    along with this program; if not, write to the Free Software
  18  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  19  */
  20
  21 /*
  22  * The Xilinx SystemACE chip support is activated by defining
  23  * CONFIG_SYSTEMACE to turn on support, and CFG_SYSTEMACE_BASE
  24  * to set the base address of the device. This code currently
  25  * assumes that the chip is connected via a byte-wide bus.
  26  *
  27  * The CONFIG_SYSTEMACE also adds to fat support the device class
  28  * "ace" that allows the user to execute "fatls ace 0" and the
  29  * like. This works by making the systemace_get_dev function
  30  * available to cmd_fat.c:get_dev and filling in a block device
  31  * description that has all the bits needed for FAT support to
  32  * read sectors.
  33  *
  34  * According to Xilinx technical support, before accessing the
  35  * SystemACE CF you need to set the following control bits:
  36  *      FORCECFGMODE : 1
  37  *      CFGMODE : 0
  38  *      CFGSTART : 0
  39  */
  40
  41 #include <common.h>
  42 #include <command.h>
  43 #include <systemace.h>
  44 #include <part.h>
  45 #include <asm/io.h>
  46
  47 #ifdef CONFIG_SYSTEMACE
  48
  49 /*
  50  * The ace_readw and writew functions read/write 16bit words, but the
  51  * offset value is the BYTE offset as most used in the Xilinx
  52  * datasheet for the SystemACE chip. The CFG_SYSTEMACE_BASE is defined
  53  * to be the base address for the chip, usually in the local
  54  * peripheral bus.
  55  */
  56 #if (CFG_SYSTEMACE_WIDTH == 8)
  57 #if !defined(__BIG_ENDIAN)
  58 #define ace_readw(off) ((readb(CFG_SYSTEMACE_BASE+off)<<8) | \
  59                         (readb(CFG_SYSTEMACE_BASE+off+1)))
  60 #define ace_writew(val, off) {writeb(val>>8, CFG_SYSTEMACE_BASE+off); \
  61                               writeb(val, CFG_SYSTEMACE_BASE+off+1);}
  62 #else
  63 #define ace_readw(off) ((readb(CFG_SYSTEMACE_BASE+off)) | \
  64                         (readb(CFG_SYSTEMACE_BASE+off+1)<<8))
  65 #define ace_writew(val, off) {writeb(val, CFG_SYSTEMACE_BASE+off); \
  66                               writeb(val>>8, CFG_SYSTEMACE_BASE+off+1);}
  67 #endif
  68 #else
  69 #define ace_readw(off) (in16(CFG_SYSTEMACE_BASE+off))
  70 #define ace_writew(val, off) (out16(CFG_SYSTEMACE_BASE+off,val))
  71 #endif
  72
  73 /* */
  74
  75 static unsigned long systemace_read(int dev, unsigned long start,
  76                                     unsigned long blkcnt, void *buffer);
  77
  78 static block_dev_desc_t systemace_dev = { 0 };
  79
  80 static int get_cf_lock(void)
  81 {
  82         int retry = 10;
  83
  84         /* CONTROLREG = LOCKREG */
  85         unsigned val = ace_readw(0x18);
  86         val |= 0x0002;
  87         ace_writew((val & 0xffff), 0x18);
  88
  89         /* Wait for MPULOCK in STATUSREG[15:0] */
  90         while (!(ace_readw(0x04) & 0x0002)) {
  91
  92                 if (retry < 0)
  93                         return -1;
  94
  95                 udelay(100000);
  96                 retry -= 1;
  97         }
  98
  99         return 0;
 100 }
 101
 102 static void release_cf_lock(void)
 103 {
 104         unsigned val = ace_readw(0x18);
 105         val &= ~(0x0002);
 106         ace_writew((val & 0xffff), 0x18);
 107 }
 108
 109 block_dev_desc_t *systemace_get_dev(int dev)
 110 {
 111         /* The first time through this, the systemace_dev object is
 112            not yet initialized. In that case, fill it in. */
 113         if (systemace_dev.blksz == 0) {
 114                 systemace_dev.if_type = IF_TYPE_UNKNOWN;
 115                 systemace_dev.dev = 0;
 116                 systemace_dev.part_type = PART_TYPE_UNKNOWN;
 117                 systemace_dev.type = DEV_TYPE_HARDDISK;
 118                 systemace_dev.blksz = 512;
 119                 systemace_dev.removable = 1;
 120                 systemace_dev.block_read = systemace_read;
 121
 122                 /*
 123                  * Ensure the correct bus mode (8/16 bits) gets enabled
 124                  */
 125                 ace_writew(CFG_SYSTEMACE_WIDTH == 8 ? 0 : 0x0001, 0);
 126
 127                 init_part(&systemace_dev);
 128
 129         }
 130
 131         return &systemace_dev;
 132 }
 133
 134 /*
 135  * This function is called (by dereferencing the block_read pointer in
 136  * the dev_desc) to read blocks of data. The return value is the
 137  * number of blocks read. A zero return indicates an error.
 138  */
 139 static unsigned long systemace_read(int dev, unsigned long start,
 140                                     unsigned long blkcnt, void *buffer)
 141 {
 142         int retry;
 143         unsigned blk_countdown;
 144         unsigned char *dp = buffer;
 145         unsigned val;
 146
 147         if (get_cf_lock() < 0) {
 148                 unsigned status = ace_readw(0x04);
 149
 150                 /* If CFDETECT is false, card is missing. */
 151                 if (!(status & 0x0010)) {
 152                         printf("** CompactFlash card not present. **\n");
 153                         return 0;
 154                 }
 155
 156                 printf("**** ACE locked away from me (STATUSREG=%04x)\n",
 157                        status);
 158                 return 0;
 159         }
 160 #ifdef DEBUG_SYSTEMACE
 161         printf("... systemace read %lu sectors at %lu\n", blkcnt, start);
 162 #endif
 163
 164         retry = 2000;
 165         for (;;) {
 166                 val = ace_readw(0x04);
 167
 168                 /* If CFDETECT is false, card is missing. */
 169                 if (!(val & 0x0010)) {
 170                         printf("**** ACE CompactFlash not found.\n");
 171                         release_cf_lock();
 172                         return 0;
 173                 }
 174
 175                 /* If RDYFORCMD, then we are ready to go. */
 176                 if (val & 0x0100)
 177                         break;
 178
 179                 if (retry < 0) {
 180                         printf("**** SystemACE not ready.\n");
 181                         release_cf_lock();
 182                         return 0;
 183                 }
 184
 185                 udelay(1000);
 186                 retry -= 1;
 187         }
 188
 189         /* The SystemACE can only transfer 256 sectors at a time, so
 190            limit the current chunk of sectors. The blk_countdown
 191            variable is the number of sectors left to transfer. */
 192
 193         blk_countdown = blkcnt;
 194         while (blk_countdown > 0) {
 195                 unsigned trans = blk_countdown;
 196
 197                 if (trans > 256)
 198                         trans = 256;
 199
 200 #ifdef DEBUG_SYSTEMACE
 201                 printf("... transfer %lu sector in a chunk\n", trans);
 202 #endif
 203                 /* Write LBA block address */
 204                 ace_writew((start >> 0) & 0xffff, 0x10);
 205                 ace_writew((start >> 16) & 0x0fff, 0x12);
 206
 207                 /* NOTE: in the Write Sector count below, a count of 0
 208                    causes a transfer of 256, so &0xff gives the right
 209                    value for whatever transfer count we want. */
 210
 211                 /* Write sector count | ReadMemCardData. */
 212                 ace_writew((trans & 0xff) | 0x0300, 0x14);
 213
 214 /*
 215  * For FPGA configuration via SystemACE is reset unacceptable
 216  * CFGDONE bit in STATUSREG is not set to 1.
 217  */
 218 #ifndef SYSTEMACE_CONFIG_FPGA
 219                 /* Reset the configruation controller */
 220                 val = ace_readw(0x18);
 221                 val |= 0x0080;
 222                 ace_writew(val, 0x18);
 223 #endif
 224
 225                 retry = trans * 16;
 226                 while (retry > 0) {
 227                         int idx;
 228
 229                         /* Wait for buffer to become ready. */
 230                         while (!(ace_readw(0x04) & 0x0020)) {
 231                                 udelay(100);
 232                         }
 233
 234                         /* Read 16 words of 2bytes from the sector buffer. */
 235                         for (idx = 0; idx < 16; idx += 1) {
 236                                 unsigned short val = ace_readw(0x40);
 237                                 *dp++ = val & 0xff;
 238                                 *dp++ = (val >> 8) & 0xff;
 239                         }
 240
 241                         retry -= 1;
 242                 }
 243
 244                 /* Clear the configruation controller reset */
 245                 val = ace_readw(0x18);
 246                 val &= ~0x0080;
 247                 ace_writew(val, 0x18);
 248
 249                 /* Count the blocks we transfer this time. */
 250                 start += trans;
 251                 blk_countdown -= trans;
 252         }
 253
 254         release_cf_lock();
 255
 256         return blkcnt;
 257 }
 258 #endif /* CONFIG_SYSTEMACE */