On Fri, 24 Aug 2012, Shilimkar, Santosh wrote: > On Fri, Aug 24, 2012 at 2:30 AM, Peter Meerwald <pmeerw@xxxxxxxxxx> wrote: > > > > On Wed, 18 Jul 2012, Javier Martinez Canillas wrote: > > > > > On Wed, Jul 18, 2012 at 10:36 AM, Shilimkar, Santosh > > > <santosh.shilimkar@xxxxxx> wrote: > > > > On Wed, Jul 18, 2012 at 1:14 PM, S, Venkatraman <svenkatr@xxxxxx> > > > > wrote: > > > >> On Wed, Jul 18, 2012 at 12:40 PM, Tony Lindgren <tony@xxxxxxxxxxx> > > > >> wrote: > > > >>> * Shilimkar, Santosh <santosh.shilimkar@xxxxxx> [120718 00:09]: > > > >>>> On Wed, Jul 18, 2012 at 12:29 PM, Tony Lindgren <tony@xxxxxxxxxxx> > > > >>>> wrote: > > > >>>> > * Javier Martinez Canillas <javier@xxxxxxxxxxxx> [120716 23:56]: > > > >>>> >> On Tue, Jul 17, 2012 at 8:45 AM, Shilimkar, Santosh > > > >>>> >> <santosh.shilimkar@xxxxxx> wrote: > > > >>>> >> > Hi, > > > >>>> >> > > > > >>>> >> > On Tue, Jul 17, 2012 at 6:00 AM, Javier Martinez Canillas > > > >>>> >> > <javier@xxxxxxxxxxxx> 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 <javier@xxxxxxxxxxxx> > > > >>>> >> >> --- > > > >>>> >> > 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 > > > > 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 > > > May be I am missing something, but why you would need below patch > for beagle with "89269ef1f0abc72c551198123e19cd4edfd43cf4" commit > enabling the DMA_OMAP for all OMAP boards. the commit just sets CONFIG_DMA_OMAP=y and CONFIG_DMADEVICES=y in omap2plus_defconfig; this does not help people updating the kernel while keeping the config, nor does it help people in configuring the kernel there is a dependency (at least for beagleboard) between MMC_OMAP_HS and DMA_OMAP, and I think this should be made explicit regards, p. -- Peter Meerwald +43-664-2444418 (mobile) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
