RE: [PATCH v5 11/15] dmaengine: imx-sdma: fix ecspi1 rx dma not work on i.mx8mm

From: Robin Gong
Date: Thu Sep 26 2019 - 21:55:20 EST


On 2019-9-25 22:53 Schrempf Frieder <frieder.schrempf@xxxxxxxxxx> wrote:
> On 25.09.19 13:26, Robin Gong wrote:
> > On 2019-9-24 21:28 Schrempf Frieder <frieder.schrempf@xxxxxxxxxx>
> wrote:
> >>
> >> Hi Robin,
> >>
> >>> From: Robin Gong <yibin.gong at nxp.com>
> >>>
> >>> Because the number of ecspi1 rx event on i.mx8mm is 0, the condition
> >>> check ignore such special case without dma channel enabled, which
> >>> caused
> >>> ecspi1 rx works failed. Actually, no need to check
> >>> event_id0/event_id1 and replace checking 'event_id1' with
> >>> 'DMA_DEV_TO_DEV', so that configure
> >>> event_id1 only in case DEV_TO_DEV.
> >>>
> >>> Signed-off-by: Robin Gong <yibin.gong at nxp.com>
> >>> Acked-by: Vinod Koul <vkoul at kernel.org>
> >>
> >> I have a custom board with i.MX8MM and SPI flash on ecspi1. I'm
> >> currently testing with v5.3 and as SPI didn't work, I tried two different
> things:
> >>
> >> 1. Removing 'dmas' and 'dma-names' from the ecspi1 node in
> imx8mm.dtsi,
> >> to use PIO instead of DMA. This works as expected and the driver
> >> boots with the following messages:
> >>
> >> spi_imx 30820000.spi: dma setup error -19, use pio
> >> m25p80 spi0.0: mx25v8035f (1024 Kbytes)
> >> spi_imx 30820000.spi: probed
> >>
> >> 2. Applying your patchset and use DMA. In this case, the flash also
> >> works fine, but there are some error messages printed while
> booting:
> >>
> >> spi_master spi0: I/O Error in DMA RX
> >> m25p80 spi0.0: SPI transfer failed: -110
> >> spi_master spi0: failed to transfer one message from queue
> >> m25p80 spi0.0: mx25v8035f (1024 Kbytes)
> >> spi_imx 30820000.spi: probed
> >>
> >> It would be great to get your patches merged and fix SPI + DMA, but
> >> for i.MX8MM, we need to get rid of the error messages. Do you have an
> >> idea, what's wrong?
>
> > Could you check if the length of spi message is bigger than fifo_size
> > during spi_nor probe? If yes, at that time maybe sdma firmware not loaded.
> > if (transfer->len < spi_imx->devtype_data->fifo_size)
>
> Indeed, most of the transfers triggered by the SPI NOR dirver are below
> fifo_size and work fine, but some are bigger. The transfers therefore try to
> use DMA, but the firmware is not loaded yet.
>
> How is this supposed to work? Shouldn't all transfers use PIO as long as the
> SDMA firmware is not loaded yet?
Yes, for ecspi should work with ram script, it's better check if sdma firmware
is ready in spi_imx_dma_configure(), need modification in sdma driver too.
I'll create another patch after this patch set accepted.
>
> (+ Cc: linux-spi@xxxxxxxxxxxxxxx)