From mboxrd@z Thu Jan 1 00:00:00 1970 From: Javier Martinez Canillas Subject: Re: [PATCH 1/1] mmc: host: enable OMAP DMA engine support for omap hosts by default Date: Wed, 18 Jul 2012 11:16:03 +0200 Message-ID: References: <1342485005-5178-1-git-send-email-javier@dowhile0.org> <20120718065951.GH6522@atomide.com> <20120718071039.GI6522@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: Sender: linux-omap-owner@vger.kernel.org To: "Shilimkar, Santosh" Cc: "S, Venkatraman" , Tony Lindgren , Javier Martinez Canillas , Kevin Hilman , Russell King , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Chris Ball , linux-mmc@vger.kernel.org List-Id: linux-mmc@vger.kernel.org On Wed, Jul 18, 2012 at 11:11 AM, Shilimkar, Santosh wrote: > On Wed, Jul 18, 2012 at 2:19 PM, Javier Martinez Canillas > wrote: >> On Wed, Jul 18, 2012 at 10:36 AM, Shilimkar, Santosh >> wrote: >>> On Wed, Jul 18, 2012 at 1:14 PM, S, Venkatraman wrote: >>>> On Wed, Jul 18, 2012 at 12:40 PM, Tony Lindgren wrote: >>>>> * Shilimkar, Santosh [120718 00:09]: >>>>>> On Wed, Jul 18, 2012 at 12:29 PM, Tony Lindgren wrote: >>>>>> > * Javier Martinez Canillas [120716 23:56]: >>>>>> >> On Tue, Jul 17, 2012 at 8:45 AM, Shilimkar, Santosh >>>>>> >> wrote: >>>>>> >> > Hi, >>>>>> >> > >>>>>> >> > On Tue, Jul 17, 2012 at 6:00 AM, Javier Martinez Canillas >>>>>> >> > wrote: >>>>>> >> >> 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 >>>>>> >> >> --- >>>>>> >> > 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 >>>>>> >> > Santosh >>>>>> >> >>>>>> >> Hi 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_defconfig >> b/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 >> 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 > > May be. But since for sure a driver knows that it needs DMA > support to be enabled, I will just select it rather than depends > on. > > Regards > santosh Yes I agree with you, I was just exploring other options :-) Best regards, Javier From mboxrd@z Thu Jan 1 00:00:00 1970 From: martinez.javier@gmail.com (Javier Martinez Canillas) Date: Wed, 18 Jul 2012 11:16:03 +0200 Subject: [PATCH 1/1] mmc: host: enable OMAP DMA engine support for omap hosts by default In-Reply-To: References: <1342485005-5178-1-git-send-email-javier@dowhile0.org> <20120718065951.GH6522@atomide.com> <20120718071039.GI6522@atomide.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Jul 18, 2012 at 11:11 AM, Shilimkar, Santosh wrote: > On Wed, Jul 18, 2012 at 2:19 PM, Javier Martinez Canillas > wrote: >> On Wed, Jul 18, 2012 at 10:36 AM, Shilimkar, Santosh >> wrote: >>> On Wed, Jul 18, 2012 at 1:14 PM, S, Venkatraman wrote: >>>> On Wed, Jul 18, 2012 at 12:40 PM, Tony Lindgren wrote: >>>>> * Shilimkar, Santosh [120718 00:09]: >>>>>> On Wed, Jul 18, 2012 at 12:29 PM, Tony Lindgren wrote: >>>>>> > * Javier Martinez Canillas [120716 23:56]: >>>>>> >> On Tue, Jul 17, 2012 at 8:45 AM, Shilimkar, Santosh >>>>>> >> wrote: >>>>>> >> > Hi, >>>>>> >> > >>>>>> >> > On Tue, Jul 17, 2012 at 6:00 AM, Javier Martinez Canillas >>>>>> >> > wrote: >>>>>> >> >> 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 >>>>>> >> >> --- >>>>>> >> > 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 >>>>>> >> > Santosh >>>>>> >> >>>>>> >> Hi 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_defconfig >> b/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 >> 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 > > May be. But since for sure a driver knows that it needs DMA > support to be enabled, I will just select it rather than depends > on. > > Regards > santosh Yes I agree with you, I was just exploring other options :-) Best regards, Javier