Re: [PATCH 2/2] ARM: OMAP4: DSS hwmods: Add OCPIF_SWSUP_IDLE to all DSS L3 slave interfaces
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.
The current OMAP4 DSS clock setup is clearly a hack that should be fixed. Regards, Benoit _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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