From: Quanyang Wang quanyang.wang@windriver.com
[ Upstream commit 8ad07d79bd56a531990a1a3f3f1c0eb19d2de806 ]
There is a data corruption issue that occurs in the reading operation (cmd:0x6c) when transmitting common data as dummy circles.
The gqspi controller has the functionality to send dummy clock circles. When writing data with the fields [receive, transmit, data_xfer] = [0,0,1] to the Generic FIFO, and configuring the correct SPI mode, the controller will transmit dummy circles.
So let's switch to hardware dummy cycles transfer to fix this issue.
Fixes: 1c26372e5aa9 ("spi: spi-zynqmp-gqspi: Update driver to use spi-mem framework") Signed-off-by: Quanyang Wang quanyang.wang@windriver.com Reviewed-by: Amit Kumar Mahapatra amit.kumar-mahapatra@xilinx.com Link: https://lore.kernel.org/r/20210408040223.23134-4-quanyang.wang@windriver.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-zynqmp-gqspi.c | 40 +++++++++++++++------------------- 1 file changed, 18 insertions(+), 22 deletions(-)
diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c index 3b39461d58b3..cf73a069b759 100644 --- a/drivers/spi/spi-zynqmp-gqspi.c +++ b/drivers/spi/spi-zynqmp-gqspi.c @@ -521,7 +521,7 @@ static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size) { u32 count = 0, intermediate;
- while ((xqspi->bytes_to_transfer > 0) && (count < size)) { + while ((xqspi->bytes_to_transfer > 0) && (count < size) && (xqspi->txbuf)) { memcpy(&intermediate, xqspi->txbuf, 4); zynqmp_gqspi_write(xqspi, GQSPI_TXD_OFST, intermediate);
@@ -580,7 +580,7 @@ static void zynqmp_qspi_fillgenfifo(struct zynqmp_qspi *xqspi, u8 nbits, genfifoentry |= GQSPI_GENFIFO_DATA_XFER; genfifoentry |= GQSPI_GENFIFO_TX; transfer_len = xqspi->bytes_to_transfer; - } else { + } else if (xqspi->rxbuf) { genfifoentry &= ~GQSPI_GENFIFO_TX; genfifoentry |= GQSPI_GENFIFO_DATA_XFER; genfifoentry |= GQSPI_GENFIFO_RX; @@ -588,6 +588,11 @@ static void zynqmp_qspi_fillgenfifo(struct zynqmp_qspi *xqspi, u8 nbits, transfer_len = xqspi->dma_rx_bytes; else transfer_len = xqspi->bytes_to_receive; + } else { + /* Sending dummy circles here */ + genfifoentry &= ~(GQSPI_GENFIFO_TX | GQSPI_GENFIFO_RX); + genfifoentry |= GQSPI_GENFIFO_DATA_XFER; + transfer_len = xqspi->bytes_to_transfer; } genfifoentry |= zynqmp_qspi_selectspimode(xqspi, nbits); xqspi->genfifoentry = genfifoentry; @@ -1011,32 +1016,23 @@ static int zynqmp_qspi_exec_op(struct spi_mem *mem, }
if (op->dummy.nbytes) { - tmpbuf = kzalloc(op->dummy.nbytes, GFP_KERNEL | GFP_DMA); - if (!tmpbuf) - return -ENOMEM; - memset(tmpbuf, 0xff, op->dummy.nbytes); - reinit_completion(&xqspi->data_completion); - xqspi->txbuf = tmpbuf; + xqspi->txbuf = NULL; xqspi->rxbuf = NULL; - xqspi->bytes_to_transfer = op->dummy.nbytes; + /* + * xqspi->bytes_to_transfer here represents the dummy circles + * which need to be sent. + */ + xqspi->bytes_to_transfer = op->dummy.nbytes * 8 / op->dummy.buswidth; xqspi->bytes_to_receive = 0; - zynqmp_qspi_write_op(xqspi, op->dummy.buswidth, + /* + * Using op->data.buswidth instead of op->dummy.buswidth here because + * we need to use it to configure the correct SPI mode. + */ + zynqmp_qspi_write_op(xqspi, op->data.buswidth, genfifoentry); zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) | GQSPI_CFG_START_GEN_FIFO_MASK); - zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST, - GQSPI_IER_TXEMPTY_MASK | - GQSPI_IER_GENFIFOEMPTY_MASK | - GQSPI_IER_TXNOT_FULL_MASK); - if (!wait_for_completion_interruptible_timeout - (&xqspi->data_completion, msecs_to_jiffies(1000))) { - err = -ETIMEDOUT; - kfree(tmpbuf); - goto return_err; - } - - kfree(tmpbuf); }
if (op->data.nbytes) {