drivers/mtd/nand/raw/sm_common.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright © 2009 - Maxim Levitsky
   4  * Common routines & support for SmartMedia/xD format
   5  */
   6 #include <linux/bitops.h>
   7 #include <linux/mtd/mtd.h>
   8
   9 /* Full oob structure as written on the flash */
  10 struct sm_oob {
  11         uint32_t reserved;
  12         uint8_t data_status;
  13         uint8_t block_status;
  14         uint8_t lba_copy1[2];
  15         uint8_t ecc2[3];
  16         uint8_t lba_copy2[2];
  17         uint8_t ecc1[3];
  18 } __packed;
  19
  20
  21 /* one sector is always 512 bytes, but it can consist of two nand pages */
  22 #define SM_SECTOR_SIZE          512
  23
  24 /* oob area is also 16 bytes, but might be from two pages */
  25 #define SM_OOB_SIZE             16
  26
  27 /* This is maximum zone size, and all devices that have more that one zone
  28    have this size */
  29 #define SM_MAX_ZONE_SIZE        1024
  30
  31 /* support for small page nand */
  32 #define SM_SMALL_PAGE           256
  33 #define SM_SMALL_OOB_SIZE       8
  34
  35
  36 int sm_register_device(struct mtd_info *mtd, int smartmedia);
  37
  38
  39 static inline int sm_sector_valid(struct sm_oob *oob)
  40 {
  41         return hweight16(oob->data_status) >= 5;
  42 }
  43
  44 static inline int sm_block_valid(struct sm_oob *oob)
  45 {
  46         return hweight16(oob->block_status) >= 7;
  47 }
  48
  49 static inline int sm_block_erased(struct sm_oob *oob)
  50 {
  51         static const uint32_t erased_pattern[4] = {
  52                 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
  53
  54         /* First test for erased block */
  55         if (!memcmp(oob, erased_pattern, sizeof(*oob)))
  56                 return 1;
  57         return 0;
  58 }