[PATCH 2/2] ARM: OMAP4: DSS hwmods: Add OCPIF_SWSUP_IDLE to all DSS L3 slave interfaces

Paul Walmsley paul at pwsan.com
Fri May 4 02:39:12 EDT 2012


Hi Archit,

On Fri, 13 Apr 2012, Archit Taneja wrote:

> On Friday 13 April 2012 02:13 PM, Cousson, Benoit wrote:
> > On 4/13/2012 10:01 AM, Archit Taneja wrote:
> > > The clock for all DSS L3 slave interfaces had been recently changed to
> > > "dss_fck" from "l3_div_ck". "dss_fck" is an optional clock in DSS
> > > clock domain
> > > which can't autoidle when enabled.
> > > 
> > > Add OCPIF_SWSUP_IDLE flag to all the L3 slave interfaces used by DSS
> > > hwmods so
> > > that clock is explicitly enabled and disabled by software. Without this,
> > > "dss_fck" would be left as enabled and the OMAP4 device won't idle
> > > even when
> > > DSS is not in use.
> > 
> > Yeah, that was done on purpose with Tomi knowning well that limitation.
> > 
> > The issue was mainly due to the lack of proper parent / child
> > relationship between the DSS (the whole subsystem) and the DSS children
> > at that time.
> > 
> > I think that Tomi posted a series to fix that for 3.4. So if we ensure
> > that every DSS IPs are children of the DSS, then pm_runtime will always
> > ensure that the DSS will be enabled each time a submodule is used.
> > 
> > So the right fix is to put back the proper iclk (l3_div) to the DSS
> > instead of the dss_fck.
> 
> Ok, I get it now. Tomi's patch series ensured the parent-child 
> dependency, but they didn't switch the iclks back to l3_div, I guess 
> that should be a part of the series too.

Just checking on this one.  Does this patch need to be updated ?


- Paul



More information about the linux-arm-kernel mailing list