Quoting Taniya Das (2018-07-09 02:34:07) > > > On 7/9/2018 1:07 PM, Stephen Boyd wrote: > > Quoting Taniya Das (2018-07-09 00:07:21) > >> > >> > >> On 7/9/2018 11:46 AM, Stephen Boyd wrote: > >>>> > >>>> > Why is the nocache flag needed? Applies to all clks in this file. > >>>> > > >>>> > >>>> This flag is required for all RCGs whose PLLs are controlled outside the > >>>> clock controller. The display code would require the recalculated rate > >>>> always. > >>> > >>> Right. Why is the PLL controlled outside of the clock controller? The > >>> rate should propagate upward to the PLL from here, so who's going > >>> outside of that? > >>> > >> The DSI0/1 PLL are not part of the display clock controller, but in the > >> display subsystem which are managed by the DRM drivers. When DRM drivers > >> query for the rate clock driver should always return the non cached rates. > > > > Why? Is the DSI PLL changing rate all the time, randomly, without going > > through the clk APIs to do so? > > > > Hmm, I am afraid I do not have an answer for this, but this was the > requirement to always return the non cached rates from the clock driver. > Ok. Who knows about this requirement? Can we add someone from the display driver to understand more? -- To unsubscribe from this list: send the line "unsubscribe linux-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
