Re: [PATCH v1] dmaengine: imx-sdma: remove BD_INTR for channel0

[Sven Van Asbroeck <thesven73@gmail.com>]

Hi Robin, see comments inline.

On Fri, Jun 14, 2019 at 4:38 AM <yibin.gong@nxp.com> wrote:
>
> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> index deea9aa..b5a1ee2 100644
> --- a/drivers/dma/imx-sdma.c
> +++ b/drivers/dma/imx-sdma.c
> @@ -742,7 +742,7 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
>         spin_lock_irqsave(&sdma->channel_0_lock, flags);
>
>         bd0->mode.command = C0_SETPM;
> -       bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
> +       bd0->mode.status = BD_DONE | BD_WRAP | BD_EXTD;

I tested this change on its own, and it seemed sufficient to make the crash
disappear.

>         bd0->mode.count = size / 2;
>         bd0->buffer_addr = buf_phys;
>         bd0->ext_buffer_addr = address;
> @@ -1064,7 +1064,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
>         context->gReg[7] = sdmac->watermark_level;
>
>         bd0->mode.command = C0_SETDM;
> -       bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
> +       bd0->mode.status = BD_DONE | BD_WRAP | BD_EXTD;

This function isn't part of the firmware load path, so how can it be related
to fixing the firmware crash?

If this is an unrelated efficiency saving, maybe it should go into its
own patch?
Maybe we want bugfix patches to be as small and specific as possible, so they
can more easily be backported to older kernels?

>         bd0->mode.count = sizeof(*context) / 4;
>         bd0->buffer_addr = sdma->context_phys;
>         bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * channel;
> --
> 2.7.4
>

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