git.sur5r.net Git - u-boot/blob - drivers/mtd/nand/nand_spl_loaders.c

   1 int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
   2 {
   3         unsigned int block, lastblock;
   4         unsigned int page, page_offset;
   5
   6         /* offs has to be aligned to a page address! */
   7         block = offs / CONFIG_SYS_NAND_BLOCK_SIZE;
   8         lastblock = (offs + size - 1) / CONFIG_SYS_NAND_BLOCK_SIZE;
   9         page = (offs % CONFIG_SYS_NAND_BLOCK_SIZE) / CONFIG_SYS_NAND_PAGE_SIZE;
  10         page_offset = offs % CONFIG_SYS_NAND_PAGE_SIZE;
  11
  12         while (block <= lastblock) {
  13                 if (!nand_is_bad_block(block)) {
  14                         /* Skip bad blocks */
  15                         while (page < CONFIG_SYS_NAND_PAGE_COUNT) {
  16                                 nand_read_page(block, page, dst);
  17                                 /*
  18                                  * When offs is not aligned to page address the
  19                                  * extra offset is copied to dst as well. Copy
  20                                  * the image such that its first byte will be
  21                                  * at the dst.
  22                                  */
  23                                 if (unlikely(page_offset)) {
  24                                         memmove(dst, dst + page_offset,
  25                                                 CONFIG_SYS_NAND_PAGE_SIZE);
  26                                         dst = (void *)((int)dst - page_offset);
  27                                         page_offset = 0;
  28                                 }
  29                                 dst += CONFIG_SYS_NAND_PAGE_SIZE;
  30                                 page++;
  31                         }
  32
  33                         page = 0;
  34                 } else {
  35                         lastblock++;
  36                 }
  37
  38                 block++;
  39         }
  40
  41         return 0;
  42 }
  43
  44 #ifdef CONFIG_SPL_UBI
  45 /*
  46  * Temporary storage for non NAND page aligned and non NAND page sized
  47  * reads. Note: This does not support runtime detected FLASH yet, but
  48  * that should be reasonably easy to fix by making the buffer large
  49  * enough :)
  50  */
  51 static u8 scratch_buf[CONFIG_SYS_NAND_PAGE_SIZE];
  52
  53 /**
  54  * nand_spl_read_block - Read data from physical eraseblock into a buffer
  55  * @block:      Number of the physical eraseblock
  56  * @offset:     Data offset from the start of @peb
  57  * @len:        Data size to read
  58  * @dst:        Address of the destination buffer
  59  *
  60  * This could be further optimized if we'd have a subpage read
  61  * function in the simple code. On NAND which allows subpage reads
  62  * this would spare quite some time to readout e.g. the VID header of
  63  * UBI.
  64  *
  65  * Notes:
  66  *      @offset + @len are not allowed to be larger than a physical
  67  *      erase block. No sanity check done for simplicity reasons.
  68  *
  69  * To support runtime detected flash this needs to be extended by
  70  * information about the actual flash geometry, but thats beyond the
  71  * scope of this effort and for most applications where fast boot is
  72  * required it is not an issue anyway.
  73  */
  74 int nand_spl_read_block(int block, int offset, int len, void *dst)
  75 {
  76         int page, read;
  77
  78         /* Calculate the page number */
  79         page = offset / CONFIG_SYS_NAND_PAGE_SIZE;
  80
  81         /* Offset to the start of a flash page */
  82         offset = offset % CONFIG_SYS_NAND_PAGE_SIZE;
  83
  84         while (len) {
  85                 /*
  86                  * Non page aligned reads go to the scratch buffer.
  87                  * Page aligned reads go directly to the destination.
  88                  */
  89                 if (offset || len < CONFIG_SYS_NAND_PAGE_SIZE) {
  90                         nand_read_page(block, page, scratch_buf);
  91                         read = min(len, CONFIG_SYS_NAND_PAGE_SIZE - offset);
  92                         memcpy(dst, scratch_buf + offset, read);
  93                         offset = 0;
  94                 } else {
  95                         nand_read_page(block, page, dst);
  96                         read = CONFIG_SYS_NAND_PAGE_SIZE;
  97                 }
  98                 page++;
  99                 len -= read;
 100                 dst += read;
 101         }
 102         return 0;
 103 }
 104 #endif