Re: [PATCH 1/3] dmaengine: qcom: gpi: set chain and link flag for duplex

From: Bjorn Andersson
Date: Tue Apr 12 2022 - 19:29:55 EST


On Wed 06 Apr 06:25 PDT 2022, Vinod Koul wrote:

> Newer platforms seem to have strict requirement for TRE flags which
> causes transaction to timeout. This was resolved to missing chain and
> link flag for duplex spi transaction.
>
> So add these two flags.
>
> Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>

Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Tested-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

> ---
> drivers/dma/qcom/gpi.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c
> index 94f3648f7483..3429ceccd13b 100644
> --- a/drivers/dma/qcom/gpi.c
> +++ b/drivers/dma/qcom/gpi.c
> @@ -1754,10 +1754,14 @@ static int gpi_create_spi_tre(struct gchan *chan, struct gpi_desc *desc,
> tre->dword[2] = u32_encode_bits(spi->rx_len, TRE_RX_LEN);
>
> tre->dword[3] = u32_encode_bits(TRE_TYPE_GO, TRE_FLAGS_TYPE);
> - if (spi->cmd == SPI_RX)
> + if (spi->cmd == SPI_RX) {
> tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOB);
> - else
> + } else if (spi->cmd == SPI_TX) {
> + tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
> + } else { /* SPI_DUPLEX */
> tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_CHAIN);
> + tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_LINK);
> + }
> }
>
> /* create the dma tre */
> --
> 2.34.1
>