This patch makes the code compatible with FIFO depths other than 4 bytes. It also simplify read/write FIFO loops.
Signed-off-by: Vikas Manocha vikas.manocha@st.com Tested-by: Stefan Roese sr@denx.de ---
Changes in v3: Rebased to spi-next-dev Changes in v2: Fixed the checkpatch.pl error
drivers/spi/cadence_qspi_apb.c | 46 ++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 23 deletions(-)
diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c index cbf0d42..d053407 100644 --- a/drivers/spi/cadence_qspi_apb.c +++ b/drivers/spi/cadence_qspi_apb.c @@ -200,18 +200,16 @@ static void cadence_qspi_apb_read_fifo_data(void *dest, unsigned int *dest_ptr = (unsigned int *)dest; unsigned int *src_ptr = (unsigned int *)src_ahb_addr;
- while (remaining > 0) { - if (remaining >= CQSPI_FIFO_WIDTH) { - *dest_ptr = readl(src_ptr); - remaining -= CQSPI_FIFO_WIDTH; - } else { - /* dangling bytes */ - temp = readl(src_ptr); - memcpy(dest_ptr, &temp, remaining); - break; - } + while (remaining >= sizeof(dest_ptr)) { + *dest_ptr = readl(src_ptr); + remaining -= sizeof(src_ptr); dest_ptr++; } + if (remaining) { + /* dangling bytes */ + temp = readl(src_ptr); + memcpy(dest_ptr, &temp, remaining); + }
return; } @@ -219,24 +217,26 @@ static void cadence_qspi_apb_read_fifo_data(void *dest, static void cadence_qspi_apb_write_fifo_data(const void *dest_ahb_addr, const void *src, unsigned int bytes) { - unsigned int temp; + unsigned int temp = 0; + int i; int remaining = bytes; unsigned int *dest_ptr = (unsigned int *)dest_ahb_addr; unsigned int *src_ptr = (unsigned int *)src;
- while (remaining > 0) { - if (remaining >= CQSPI_FIFO_WIDTH) { - writel(*src_ptr, dest_ptr); - remaining -= sizeof(unsigned int); - } else { - /* dangling bytes */ - memcpy(&temp, src_ptr, remaining); - writel(temp, dest_ptr); - break; - } - src_ptr++; + while (remaining >= CQSPI_FIFO_WIDTH) { + for (i = CQSPI_FIFO_WIDTH/sizeof(src_ptr) - 1; i >= 0; i--) + writel(*(src_ptr+i), dest_ptr+i); + src_ptr += CQSPI_FIFO_WIDTH/sizeof(src_ptr); + remaining -= CQSPI_FIFO_WIDTH; + } + if (remaining) { + /* dangling bytes */ + i = remaining/sizeof(dest_ptr); + memcpy(&temp, src_ptr+i, remaining % sizeof(dest_ptr)); + writel(temp, dest_ptr+i); + for (--i; i >= 0; i--) + writel(*(src_ptr+i), dest_ptr+i); } - return; }