On Thu, Nov 18, 2010 at 04:21:48PM +0530, G, Manjunath Kondaiah wrote: > Certain errata's in OMAP2+ processors will require forcing > master standby to "no standby" mode before completing on going > operation. Without this, the results will be unpredictable. > > Since current implementation of PM run time framework does not support > changing sysconfig settings during middle of the on going operation, > these API's will support the same. One API will force the device's > sysconfig mstandby mode settings to "no standby" and other API will > releases "no standby" mode and sets it to "smart standby" or "no > standbyË depending on HWMOD_SWSUP_MSTANDBY value. > > These API's should be used by device drivers only incase of > erratum applicable to their modules if there is no other methods > to resolve. > > These API's are required for multiple DMA errata's which require > putting DMA controller in no mstandby mode before stopping dma. > > The applicable errata's: > 1. Errata ID: i557(Applicable for omap36xx all ES versions) > The channel hangs when the Pause bit (DMA4_CDPi [7] ) is cleared > through config port while in Standby. > > 2. Errata ID: i541(all omap2plus except omap4) > sDMA FIFO draining does not finish > > 3. OMAP3430 ES1.0(Errata ID:i88) will require DMA to be put in > no mstandby mode before disabling the channel after completing > the data transfer operation. > > Also fixes typo HWMOD_SWSUP_MSTDBY to HWMOD_SWSUP_MSTANDBY in > omap_hwmod.h > > Signed-off-by: G, Manjunath Kondaiah <manjugk@xxxxxx> > Cc: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx> > Cc: Paul Walmsley <paul@xxxxxxxxx> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > --- > Change summary: > v2: Review comments incorporated for: > https://patchwork.kernel.org/patch/282212/ > > arch/arm/mach-omap2/omap_hwmod.c | 45 +++++++++++++++- > arch/arm/plat-omap/include/plat/omap_device.h | 3 +- > arch/arm/plat-omap/include/plat/omap_hwmod.h | 4 +- > arch/arm/plat-omap/omap_device.c | 73 +++++++++++++++++++++++++ > 4 files changed, 122 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c > index 5a30658..9c1c2fc 100644 > --- a/arch/arm/mach-omap2/omap_hwmod.c > +++ b/arch/arm/mach-omap2/omap_hwmod.c > @@ -1427,6 +1427,50 @@ int omap_hwmod_set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode) > } > > /** > + * omap_hwmod_set_master_standbymode - set the hwmod's OCP mstandby mode > + * @oh: struct omap_hwmod * > + * @midlemode: flag to set mstandby to either "no standby" or "smart standby" > + * > + * Sets the IP block's OCP mstandby mode in hardware, and updates our > + * local copy. Intended to be used by drivers that have some erratum > + * that requires direct manipulation of the MIDLEMODE bits. Returns > + * -EINVAL if @oh is null, or passes along the return value from > + * _set_master_standbymode(). > + * > + * Any users of this function should be scrutinized carefully. > + */ > +int omap_hwmod_set_master_standbymode(struct omap_hwmod *oh, u8 idlemode) > +{ > + u32 v; > + u8 sf; > + int retval = 0; > + > + if (!oh) > + return -EINVAL; > + > + v = oh->_sysc_cache; > + > + if (!oh->class->sysc) > + return -EINVAL; > + Sorry. I forgot to take mutex here. I will add this change and repost this patch. -Manjunath [...] -- 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
