On Mon, Nov 12, 2018 at 04:30:29PM +0100, Geert Uytterhoeven wrote:
> CC SuperH
>
> On Mon, Nov 12, 2018 at 4:22 PM Geert Uytterhoeven
> <geert+renesas@xxxxxxxxx> wrote:
> > Renesas R-Mobile APE6 support is currently unused:
> > - DMA slaves were never enabled in r8a73a4.dtsi,
> > - The driver relies on legacy filter matching and describing all
> > slaves and MID/RIDs in a table, unlike modern DMA engine drivers for
> > similar hardware like rcar-dmac,
> > - The driver doesn't seem to work well.
> >
> > Remove the driver, it can be resurrected from git history when needed.
> >
> > As this was the last user of SH_DMAE_BASE on Renesas ARM SoCs, the
> > sh-dma-engine driver core is now used on SuperH only.
> >
> > Note that the DT bindings are still present, as r8a73a4.dtsi uses them.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> > ---
> > Notes:
> > 1. As Renesas ARM SoCs no longer use drivers/dma/sh/shdma-base.c, the
> > task to remove use of the deprecated dma_slave_config.direction
> > field gets thrown into the SuperH maintainers' basket ;-)
> > 2. This affects shmobile_defconfig and renesas_defconfig
> > (CONFIG_SH_DMAE_BASE and CONFIG_SH_DMAE are no longer enabled by
> > default).
> > 3. I tried to get SCIFA DMA to work by:
> > - Applying the DT and driver patches below,
> > - Reverting 219fb0c1436e4893 ("serial: sh-sci: Remove the
> > platform data dma slave rx/tx channel IDs").
> > After that, serial console output using DMA seems to work, but the
> > system locks up when receiving any serial console input.
> > Probably it is easier to add r8a73a4 support to rcar-dmac.
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
