LXR uboot/drivers/mtd/nand/raw/nand_spl

   1int 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 */
  51static 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 */
  74int 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
 105