Re: [PATCH mmc/next v2 3/4] mmc: renesas-sdhi: add support for R-Car Gen3 SDHI DMAC

[Simon Horman <horms@verge.net.au>]

On Fri, Jun 16, 2017 at 11:58:53AM +0200, Simon Horman wrote:
> Add a new variant of the SDHI driver to support R-Car Gen3 with DMA via
> on-chip bus mastering.  Since the DMAC is in a part of the SDHI module it
> is not suitable to be used via DMA Engine.
> 
> Clearing of DM_CM_INFO1 after DMA thanks to Dirk Behme
> 
> Cc: Dirk Behme <dirk.behme@de.bosch.com>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> Signed-off-by: Ai Kyuse <ai.kyuse.uw@renesas.com>
> ---
> v2
> * Enhanced help text and changelog
> ---
>  drivers/mmc/host/Kconfig                      |  19 ++
>  drivers/mmc/host/Makefile                     |   8 +-
>  drivers/mmc/host/renesas_sdhi_internal_dmac.c | 275 ++++++++++++++++++++++++++
>  drivers/mmc/host/renesas_sdhi_sys_dmac.c      |   2 +-
>  drivers/mmc/host/tmio_mmc.h                   |   1 +
>  5 files changed, 303 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/mmc/host/renesas_sdhi_internal_dmac.c
> 
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 5755b69f2f72..81c81ed19735 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -575,10 +575,29 @@ config MMC_SDHI
>  	depends on SUPERH || ARM || ARM64
>  	depends on SUPERH || ARCH_RENESAS || COMPILE_TEST
>  	select MMC_TMIO_CORE
> +	select MMC_SDHI_SYS_DMAC if (SUPERH || ARM)
> +	select MMC_SDHI_INTERNAL_DMAC if ARM64
>  	help
>  	  This provides support for the SDHI SD/SDIO controller found in
>  	  Renesas SuperH, ARM and ARM64 based SoCs
>  
> +config MMC_SDHI_SYS_DMAC
> +	tristate "DMA for SDHI SD/SDIO controllers using SYS-DMAC"
> +	depends on MMC_SDHI
> +	help
> +	  This provides DMA support for SDHI SD/SDIO controllers
> +	  using SYS-DMAC via DMA Engine. This supports the controllers
> +	  found in SuperH and Renesas ARM based SoCs.
> +
> +config MMC_SDHI_INTERNAL_DMAC
> +	tristate "DMA for SDHI SD/SDIO controllers using on-chip bus mastering"

0-day tells me that building fails on arm/allmodconfig due to
writeq not being defined. I believe this is because it only exists on
64bit systems. My proposed fix for v3 is:

	depends on 64BIT


> +	depends on ARM64 || COMPILE_TEST
> +	depends on MMC_SDHI
> +	help
> +	  This provides DMA support for SDHI SD/SDIO controllers
> +	  using on-chip bus mastering. This supports the controllers
> +	  found in arm64 based SoCs.
> +
>  config MMC_CB710
>  	tristate "ENE CB710 MMC/SD Interface support"
>  	depends on PCI

> diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> index 4d4547116311..8c46766c000c 100644
> --- a/drivers/mmc/host/Makefile
> +++ b/drivers/mmc/host/Makefile

...

> +static void
> +renesas_sdhi_internal_dmac_dm_write(struct tmio_mmc_host *host,
> +				    int addr, u64 val)
> +{
> +	writeq(val, host->ctl + addr);
> +}

...