[PATCH 1/1] mmc: host: enable OMAP DMA engine support for omap hosts by default
From: Peter Meerwald <hidden>
Date: 2012-08-23 21:00:42
Also in:
linux-mmc, linux-omap
On Wed, 18 Jul 2012, Javier Martinez Canillas wrote:
quoted hunk ↗ jump to hunk
On Wed, Jul 18, 2012 at 10:36 AM, Shilimkar, Santosh [off-list ref] wrote:quoted
On Wed, Jul 18, 2012 at 1:14 PM, S, Venkatraman [off-list ref] wrote:quoted
On Wed, Jul 18, 2012 at 12:40 PM, Tony Lindgren [off-list ref] wrote:quoted
* Shilimkar, Santosh [off-list ref] [120718 00:09]:quoted
On Wed, Jul 18, 2012 at 12:29 PM, Tony Lindgren [off-list ref] wrote:quoted
* Javier Martinez Canillas [off-list ref] [120716 23:56]:quoted
On Tue, Jul 17, 2012 at 8:45 AM, Shilimkar, Santosh [off-list ref] wrote:quoted
Hi, On Tue, Jul 17, 2012 at 6:00 AM, Javier Martinez Canillas [off-list ref] wrote:quoted
The OMAP MMC and OMAP High Speed MMC hosts now use entirely the DMA engine API instead of the previous private DMA API implementation. So, if the kernel is built with support for any of these hosts but it doesn't support DMA devices nor OMAP DMA support, it fails when trying to obtain a DMA channel which leads to the following error on an OMAP3 IGEPv2 Rev.C board (and probably on most OMAP boards with MMC support): [ 2.199981] omap_hsmmc omap_hsmmc.1: unable to obtain RX DMA engine channel 48 [ 2.215087] omap_hsmmc omap_hsmmc.0: unable to obtain RX DMA engine channel 62 selecting automatically CONFIG_DMADEVICES and CONFIG_DMA_OMAP solves it. Signed-off-by: Javier Martinez Canillas <javier@dowhile0.org> ---Considering, we are updating drivers to select the DMA engine, can you also include "drivers/spi/spi-omap2-mcspi.c" which is also updated for DMA engine. Regards SantoshHi Santosh, Ok, I'll send a v2 now which includes spi-omap2-mcspi then.I don't think we should do this, the drivers should work with and without dma. This just needs to be added to the omap2plus_defconfig.Well this was not decided based on any DMA CONFIG option before for the subject drivers. It is already by default enabled if the DMA is supported by the driver IP. There is a possibility to disable it from driver platform/dt data so that still remains.I think it should rather be that if the driver is broken and does not work without DMA, it should have depends on CONFIG_DMA_OMAP.I can confirm that omap MMC can't work without DMA; polled mode is not supported / implemented.Same case for SPI driver as well. It uses DMA for everything except the cases where DMA doesn't make sense like 1 byte/2 byte etc. And its not configurable, At least considering this, it is better we do this per driver than enabling it at SOC config. Regards Santosh --Hi Santosh, And what about enabling it at the SoC config level but making the drivers dependant on CONFIG_DMADEVICES and CONFIG_DMA_OMAP? If you agree I can send something like this in two different patches (one for the omap2plus_defconfig and another to make the drivers dependant on the config option):diff --git a/arch/arm/configs/omap2plus_defconfigb/arch/arm/configs/omap2plus_defconfig index b152de7..e58edc3 100644--- a/arch/arm/configs/omap2plus_defconfig +++ b/arch/arm/configs/omap2plus_defconfig@@ -193,6 +193,8 @@ CONFIG_MMC_OMAP_HS=y CONFIG_RTC_CLASS=y CONFIG_RTC_DRV_TWL92330=y CONFIG_RTC_DRV_TWL4030=y +CONFIG_DMADEVICES=y +CONFIG_DMA_OMAP=y CONFIG_EXT2_FS=y CONFIG_EXT3_FS=y # CONFIG_EXT3_FS_XATTR is not set
above has been merged, 89269ef1f0abc72c551198123e19cd4edfd43cf4 but I am missing the patches below in mainline (3.6-rc3) -- what happened? as Javier pointed out in https://patchwork.kernel.org/patch/1203391/, MMC is broken support e.g. on beagleboard unless DMA_OMAP is defined I suggest to take below patches and help to avoid some extra gray hair for people looking for a fix for non-booting beagleboards thanks, p.
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diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index aa131b3..314c7bd 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig@@ -231,7 +231,7 @@ config MMC_SDHCI_S3C_DMA config MMC_OMAP tristate "TI OMAP Multimedia Card Interface support" - depends on ARCH_OMAP + depends on ARCH_OMAP && DMADEVICES && DMA_OMAP select TPS65010 if MACH_OMAP_H2 help This selects the TI OMAP Multimedia card Interface.@@ -242,7 +242,8 @@ config MMC_OMAP config MMC_OMAP_HS tristate "TI OMAP High Speed Multimedia Card Interface support" - depends on SOC_OMAP2430 || ARCH_OMAP3 || ARCH_OMAP4 + depends on (SOC_OMAP2430 || ARCH_OMAP3 || ARCH_OMAP4) && \ + DMADEVICES && DMA_OMAP help This selects the TI OMAP High Speed Multimedia card Interface. If you have an OMAP2430 or OMAP3 board or OMAP4 board with adiff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index cd2fe35..1c23242 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig@@ -237,7 +237,7 @@ config SPI_OMAP_UWIRE config SPI_OMAP24XX tristate "McSPI driver for OMAP" - depends on ARCH_OMAP2PLUS + depends on ARCH_OMAP2PLUS && DMADEVICES && DMA_OMAP help SPI master controller for OMAP24XX and later Multichannel SPI (McSPI) modules.
-- Peter Meerwald +43-664-2444418 (mobile)