Re: [PATCH v5 5/5] spi: spi-qcom-qspi: Add DMA mode support

[Doug Anderson <dianders@chromium.org>]

Hi,

On Mon, Apr 24, 2023 at 2:32 AM Vijaya Krishna Nivarthi
<quic_vnivarth@quicinc.com> wrote:
>
> Current driver supports only PIO mode.
>
> HW supports DMA, so add DMA mode support to the driver
> for better performance for larger xfers.
>
> Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
> ---
> v4 -> v5:
> - dropped xfer_mode
> - clear all interrupts in handle_err()
> - dont log ptr value
> - dropped some dev_err()
> - converted some dev_err() to dev_warn_once()
> - drop few redundant comments
> - can_dma() disabled if iommus not present in dev_node
> - other nits
>
> v3 -> v4:
> - corrected tabs spacing
> - dropped dma data descriptors
> - dropped INVALID from xfer_mode enum
> - qspi_buswidth_to_iomode() to return iomode without shifting
> - dropped non-functional change in qcom_qspi_set_speed()
> - drop redundant call to wmb()
> - fallback to pio if dma fails to setup
> - use dmam_pool_create() the devm version
> - thus drop dma_pool_destroy()
> - set dma_alignment field in probe()
> - other minor changes
>
> v2 -> v3:
> - dropped Reported-by tag
>
> v1 -> v2:
> - modified commit message
> - addressed kernel test robot error
> - correct placement of header file includes
> - added more comments
> - coding style related changes
> - renamed variables
> - used u32/u8 instead of uint32_t/8_t
> - removed unnecessary casting
> - retain same MSTR_CONFIG as PIO for DMA
> - unset fragment bit only for last cmd_desc of last xfer
> ---
>  drivers/spi/spi-qcom-qspi.c | 218 ++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 212 insertions(+), 6 deletions(-)

Reviewed-by: Douglas Anderson <dianders@chromium.org>