drivers/mtd/lpddr/qinfo_probe.c

   1 /*
   2  * Probing flash chips with QINFO records.
   3  * (C) 2008 Korolev Alexey <akorolev@infradead.org>
   4  * (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version 2
   9  * of the License, or (at your option) 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., 51 Franklin Street, Fifth Floor, Boston, MA
  19  * 02110-1301, USA.
  20  */
  21 #include <linux/module.h>
  22 #include <linux/types.h>
  23 #include <linux/kernel.h>
  24 #include <linux/init.h>
  25 #include <linux/errno.h>
  26 #include <linux/slab.h>
  27 #include <linux/interrupt.h>
  28
  29 #include <linux/mtd/xip.h>
  30 #include <linux/mtd/map.h>
  31 #include <linux/mtd/pfow.h>
  32 #include <linux/mtd/qinfo.h>
  33
  34 static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr);
  35 struct mtd_info *lpddr_probe(struct map_info *map);
  36 static struct lpddr_private *lpddr_probe_chip(struct map_info *map);
  37 static int lpddr_pfow_present(struct map_info *map,
  38                         struct lpddr_private *lpddr);
  39
  40 static struct qinfo_query_info qinfo_array[] = {
  41         /* General device info */
  42         {0, 0, "DevSizeShift", "Device size 2^n bytes"},
  43         {0, 3, "BufSizeShift", "Program buffer size 2^n bytes"},
  44         /* Erase block information */
  45         {1, 1, "TotalBlocksNum", "Total number of blocks"},
  46         {1, 2, "UniformBlockSizeShift", "Uniform block size 2^n bytes"},
  47         /* Partition information */
  48         {2, 1, "HWPartsNum", "Number of hardware partitions"},
  49         /* Optional features */
  50         {5, 1, "SuspEraseSupp", "Suspend erase supported"},
  51         /* Operation typical time */
  52         {10, 0, "SingleWordProgTime", "Single word program 2^n u-sec"},
  53         {10, 1, "ProgBufferTime", "Program buffer write 2^n u-sec"},
  54         {10, 2, "BlockEraseTime", "Block erase 2^n m-sec"},
  55         {10, 3, "FullChipEraseTime", "Full chip erase 2^n m-sec"},
  56 };
  57
  58 static long lpddr_get_qinforec_pos(struct map_info *map, char *id_str)
  59 {
  60         int qinfo_lines = ARRAY_SIZE(qinfo_array);
  61         int i;
  62         int bankwidth = map_bankwidth(map) * 8;
  63         int major, minor;
  64
  65         for (i = 0; i < qinfo_lines; i++) {
  66                 if (strcmp(id_str, qinfo_array[i].id_str) == 0) {
  67                         major = qinfo_array[i].major & ((1 << bankwidth) - 1);
  68                         minor = qinfo_array[i].minor & ((1 << bankwidth) - 1);
  69                         return minor | (major << bankwidth);
  70                 }
  71         }
  72         printk(KERN_ERR"%s qinfo id string is wrong! \n", map->name);
  73         BUG();
  74         return -1;
  75 }
  76
  77 static uint16_t lpddr_info_query(struct map_info *map, char *id_str)
  78 {
  79         unsigned int dsr, val;
  80         int bits_per_chip = map_bankwidth(map) * 8;
  81         unsigned long adr = lpddr_get_qinforec_pos(map, id_str);
  82         int attempts = 20;
  83
  84         /* Write a request for the PFOW record */
  85         map_write(map, CMD(LPDDR_INFO_QUERY),
  86                         map->pfow_base + PFOW_COMMAND_CODE);
  87         map_write(map, CMD(adr & ((1 << bits_per_chip) - 1)),
  88                         map->pfow_base + PFOW_COMMAND_ADDRESS_L);
  89         map_write(map, CMD(adr >> bits_per_chip),
  90                         map->pfow_base + PFOW_COMMAND_ADDRESS_H);
  91         map_write(map, CMD(LPDDR_START_EXECUTION),
  92                         map->pfow_base + PFOW_COMMAND_EXECUTE);
  93
  94         while ((attempts--) > 0) {
  95                 dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
  96                 if (dsr & DSR_READY_STATUS)
  97                         break;
  98                 udelay(10);
  99         }
 100
 101         val = CMDVAL(map_read(map, map->pfow_base + PFOW_COMMAND_DATA));
 102         return val;
 103 }
 104
 105 static int lpddr_pfow_present(struct map_info *map, struct lpddr_private *lpddr)
 106 {
 107         map_word pfow_val[4];
 108
 109         /* Check identification string */
 110         pfow_val[0] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_P);
 111         pfow_val[1] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_F);
 112         pfow_val[2] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_O);
 113         pfow_val[3] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_W);
 114
 115         if (!map_word_equal(map, CMD('P'), pfow_val[0]))
 116                 goto out;
 117
 118         if (!map_word_equal(map, CMD('F'), pfow_val[1]))
 119                 goto out;
 120
 121         if (!map_word_equal(map, CMD('O'), pfow_val[2]))
 122                 goto out;
 123
 124         if (!map_word_equal(map, CMD('W'), pfow_val[3]))
 125                 goto out;
 126
 127         return 1;       /* "PFOW" is found */
 128 out:
 129         printk(KERN_WARNING"%s: PFOW string at 0x%lx is not found \n",
 130                                         map->name, map->pfow_base);
 131         return 0;
 132 }
 133
 134 static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr)
 135 {
 136
 137         lpddr->qinfo = kzalloc(sizeof(struct qinfo_chip), GFP_KERNEL);
 138         if (!lpddr->qinfo) {
 139                 printk(KERN_WARNING "%s: no memory for LPDDR qinfo structure\n",
 140                                 map->name);
 141                 return 0;
 142         }
 143
 144         /* Get the ManuID */
 145         lpddr->ManufactId = CMDVAL(map_read(map, map->pfow_base + PFOW_MANUFACTURER_ID));
 146         /* Get the DeviceID */
 147         lpddr->DevId = CMDVAL(map_read(map, map->pfow_base + PFOW_DEVICE_ID));
 148         /* read parameters from chip qinfo table */
 149         lpddr->qinfo->DevSizeShift = lpddr_info_query(map, "DevSizeShift");
 150         lpddr->qinfo->TotalBlocksNum = lpddr_info_query(map, "TotalBlocksNum");
 151         lpddr->qinfo->BufSizeShift = lpddr_info_query(map, "BufSizeShift");
 152         lpddr->qinfo->HWPartsNum = lpddr_info_query(map, "HWPartsNum");
 153         lpddr->qinfo->UniformBlockSizeShift =
 154                                 lpddr_info_query(map, "UniformBlockSizeShift");
 155         lpddr->qinfo->SuspEraseSupp = lpddr_info_query(map, "SuspEraseSupp");
 156         lpddr->qinfo->SingleWordProgTime =
 157                                 lpddr_info_query(map, "SingleWordProgTime");
 158         lpddr->qinfo->ProgBufferTime = lpddr_info_query(map, "ProgBufferTime");
 159         lpddr->qinfo->BlockEraseTime = lpddr_info_query(map, "BlockEraseTime");
 160         return 1;
 161 }
 162 static struct lpddr_private *lpddr_probe_chip(struct map_info *map)
 163 {
 164         struct lpddr_private lpddr;
 165         struct lpddr_private *retlpddr;
 166         int numvirtchips;
 167
 168
 169         if ((map->pfow_base + 0x1000) >= map->size) {
 170                 printk(KERN_NOTICE"%s Probe at base (0x%08lx) past the end of"
 171                                 "the map(0x%08lx)\n", map->name,
 172                                 (unsigned long)map->pfow_base, map->size - 1);
 173                 return NULL;
 174         }
 175         memset(&lpddr, 0, sizeof(struct lpddr_private));
 176         if (!lpddr_pfow_present(map, &lpddr))
 177                 return NULL;
 178
 179         if (!lpddr_chip_setup(map, &lpddr))
 180                 return NULL;
 181
 182         /* Ok so we found a chip */
 183         lpddr.chipshift = lpddr.qinfo->DevSizeShift;
 184         lpddr.numchips = 1;
 185
 186         numvirtchips = lpddr.numchips * lpddr.qinfo->HWPartsNum;
 187         retlpddr = kzalloc(sizeof(struct lpddr_private) +
 188                         numvirtchips * sizeof(struct flchip), GFP_KERNEL);
 189         if (!retlpddr)
 190                 return NULL;
 191
 192         memcpy(retlpddr, &lpddr, sizeof(struct lpddr_private));
 193
 194         retlpddr->numchips = numvirtchips;
 195         retlpddr->chipshift = retlpddr->qinfo->DevSizeShift -
 196                                 __ffs(retlpddr->qinfo->HWPartsNum);
 197
 198         return retlpddr;
 199 }
 200
 201 struct mtd_info *lpddr_probe(struct map_info *map)
 202 {
 203         struct mtd_info *mtd = NULL;
 204         struct lpddr_private *lpddr;
 205
 206         /* First probe the map to see if we havecan open PFOW here */
 207         lpddr = lpddr_probe_chip(map);
 208         if (!lpddr)
 209                 return NULL;
 210
 211         map->fldrv_priv = lpddr;
 212         mtd = lpddr_cmdset(map);
 213         if (mtd) {
 214                 if (mtd->size > map->size) {
 215                         printk(KERN_WARNING "Reducing visibility of %ldKiB chip"
 216                                 "to %ldKiB\n", (unsigned long)mtd->size >> 10,
 217                                 (unsigned long)map->size >> 10);
 218                         mtd->size = map->size;
 219                 }
 220                 return mtd;
 221         }
 222
 223         kfree(lpddr->qinfo);
 224         kfree(lpddr);
 225         map->fldrv_priv = NULL;
 226         return NULL;
 227 }
 228
 229 static struct mtd_chip_driver lpddr_chipdrv = {
 230         .probe          = lpddr_probe,
 231         .name           = "qinfo_probe",
 232         .module         = THIS_MODULE
 233 };
 234
 235 static int __init lpddr_probe_init(void)
 236 {
 237         register_mtd_chip_driver(&lpddr_chipdrv);
 238         return 0;
 239 }
 240
 241 static void __exit lpddr_probe_exit(void)
 242 {
 243         unregister_mtd_chip_driver(&lpddr_chipdrv);
 244 }
 245
 246 module_init(lpddr_probe_init);
 247 module_exit(lpddr_probe_exit);
 248
 249 MODULE_LICENSE("GPL");
 250 MODULE_AUTHOR("Vasiliy Leonenko <vasiliy.leonenko@gmail.com>");
 251 MODULE_DESCRIPTION("Driver to probe qinfo flash chips");
 252