return false;
}
-/**
- * gpmi_copy_bits - copy bits from one memory region to another
- * @dst: destination buffer
- * @dst_bit_off: bit offset we're starting to write at
- * @src: source buffer
- * @src_bit_off: bit offset we're starting to read from
- * @nbits: number of bits to copy
- *
- * This functions copies bits from one memory region to another, and is used by
- * the GPMI driver to copy ECC sections which are not guaranteed to be byte
- * aligned.
- *
- * src and dst should not overlap.
- *
- */
-static void gpmi_copy_bits(u8 *dst, size_t dst_bit_off, const u8 *src,
- size_t src_bit_off, size_t nbits)
-{
- size_t i;
- size_t nbytes;
- u32 src_buffer = 0;
- size_t bits_in_src_buffer = 0;
-
- if (!nbits)
- return;
-
- /*
- * Move src and dst pointers to the closest byte pointer and store bit
- * offsets within a byte.
- */
- src += src_bit_off / 8;
- src_bit_off %= 8;
-
- dst += dst_bit_off / 8;
- dst_bit_off %= 8;
-
- /*
- * Initialize the src_buffer value with bits available in the first
- * byte of data so that we end up with a byte aligned src pointer.
- */
- if (src_bit_off) {
- src_buffer = src[0] >> src_bit_off;
- if (nbits >= (8 - src_bit_off)) {
- bits_in_src_buffer += 8 - src_bit_off;
- } else {
- src_buffer &= GENMASK(nbits - 1, 0);
- bits_in_src_buffer += nbits;
- }
- nbits -= bits_in_src_buffer;
- src++;
- }
-
- /* Calculate the number of bytes that can be copied from src to dst. */
- nbytes = nbits / 8;
-
- /* Try to align dst to a byte boundary. */
- if (dst_bit_off) {
- if (bits_in_src_buffer < (8 - dst_bit_off) && nbytes) {
- src_buffer |= src[0] << bits_in_src_buffer;
- bits_in_src_buffer += 8;
- src++;
- nbytes--;
- }
-
- if (bits_in_src_buffer >= (8 - dst_bit_off)) {
- dst[0] &= GENMASK(dst_bit_off - 1, 0);
- dst[0] |= src_buffer << dst_bit_off;
- src_buffer >>= (8 - dst_bit_off);
- bits_in_src_buffer -= (8 - dst_bit_off);
- dst_bit_off = 0;
- dst++;
- if (bits_in_src_buffer > 7) {
- bits_in_src_buffer -= 8;
- dst[0] = src_buffer;
- dst++;
- src_buffer >>= 8;
- }
- }
- }
-
- if (!bits_in_src_buffer && !dst_bit_off) {
- /*
- * Both src and dst pointers are byte aligned, thus we can
- * just use the optimized memcpy function.
- */
- if (nbytes)
- memcpy(dst, src, nbytes);
- } else {
- /*
- * src buffer is not byte aligned, hence we have to copy each
- * src byte to the src_buffer variable before extracting a byte
- * to store in dst.
- */
- for (i = 0; i < nbytes; i++) {
- src_buffer |= src[i] << bits_in_src_buffer;
- dst[i] = src_buffer;
- src_buffer >>= 8;
- }
- }
- /* Update dst and src pointers */
- dst += nbytes;
- src += nbytes;
-
- /*
- * nbits is the number of remaining bits. It should not exceed 8 as
- * we've already copied as much bytes as possible.
- */
- nbits %= 8;
-
- /*
- * If there's no more bits to copy to the destination and src buffer
- * was already byte aligned, then we're done.
- */
- if (!nbits && !bits_in_src_buffer)
- return;
-
- /* Copy the remaining bits to src_buffer */
- if (nbits)
- src_buffer |= (*src & GENMASK(nbits - 1, 0)) <<
- bits_in_src_buffer;
- bits_in_src_buffer += nbits;
-
- /*
- * In case there were not enough bits to get a byte aligned dst buffer
- * prepare the src_buffer variable to match the dst organization (shift
- * src_buffer by dst_bit_off and retrieve the least significant bits
- * from dst).
- */
- if (dst_bit_off)
- src_buffer = (src_buffer << dst_bit_off) |
- (*dst & GENMASK(dst_bit_off - 1, 0));
- bits_in_src_buffer += dst_bit_off;
-
- /*
- * Keep most significant bits from dst if we end up with an unaligned
- * number of bits.
- */
- nbytes = bits_in_src_buffer / 8;
- if (bits_in_src_buffer % 8) {
- src_buffer |= (dst[nbytes] &
- GENMASK(7, bits_in_src_buffer % 8)) <<
- (nbytes * 8);
- nbytes++;
- }
-
- /* Copy the remaining bytes to dst */
- for (i = 0; i < nbytes; i++) {
- dst[i] = src_buffer;
- src_buffer >>= 8;
- }
-}
-
/* add our owner bbt descriptor */
static uint8_t scan_ff_pattern[] = { 0xff };
static struct nand_bbt_descr gpmi_bbt_descr = {
* inline (interleaved with payload DATA), and do not align data chunk on
* byte boundaries.
* We thus need to take care moving the payload data and ECC bits stored in the
- * page into the provided buffers, which is why we're using gpmi_copy_bits.
+ * page into the provided buffers, which is why we're using nand_extract_bits().
*
* See set_geometry_by_ecc_info inline comments to have a full description
* of the layout used by the GPMI controller.
/* Extract interleaved payload data and ECC bits */
for (step = 0; step < nfc_geo->ecc_chunk_count; step++) {
if (buf)
- gpmi_copy_bits(buf, step * eccsize * 8,
- tmp_buf, src_bit_off,
- eccsize * 8);
+ nand_extract_bits(buf, step * eccsize, tmp_buf,
+ src_bit_off, eccsize * 8);
src_bit_off += eccsize * 8;
/* Align last ECC block to align a byte boundary */
eccbits += 8 - ((oob_bit_off + eccbits) % 8);
if (oob_required)
- gpmi_copy_bits(oob, oob_bit_off,
- tmp_buf, src_bit_off,
- eccbits);
+ nand_extract_bits(oob, oob_bit_off, tmp_buf,
+ src_bit_off, eccbits);
src_bit_off += eccbits;
oob_bit_off += eccbits;
* inline (interleaved with payload DATA), and do not align data chunk on
* byte boundaries.
* We thus need to take care moving the OOB area at the right place in the
- * final page, which is why we're using gpmi_copy_bits.
+ * final page, which is why we're using nand_extract_bits().
*
* See set_geometry_by_ecc_info inline comments to have a full description
* of the layout used by the GPMI controller.
/* Interleave payload data and ECC bits */
for (step = 0; step < nfc_geo->ecc_chunk_count; step++) {
if (buf)
- gpmi_copy_bits(tmp_buf, dst_bit_off,
- buf, step * eccsize * 8, eccsize * 8);
+ nand_extract_bits(tmp_buf, dst_bit_off, buf,
+ step * eccsize * 8, eccsize * 8);
dst_bit_off += eccsize * 8;
/* Align last ECC block to align a byte boundary */
eccbits += 8 - ((oob_bit_off + eccbits) % 8);
if (oob_required)
- gpmi_copy_bits(tmp_buf, dst_bit_off,
- oob, oob_bit_off, eccbits);
+ nand_extract_bits(tmp_buf, dst_bit_off, oob,
+ oob_bit_off, eccbits);
dst_bit_off += eccbits;
oob_bit_off += eccbits;
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