[PATCH v2 2/2] drm/msm: Set CLK_IGNORE_UNUSED flag for PLL clocks

[Stephen Boyd]

On 10/27, Archit Taneja wrote:
> The DSI/HDMI PLLs in MSM require resources like interface clocks, power
> domains to be enabled before we can access their registers.
> 
> The clock framework doesn't have a mechanism at the moment where we can
> tie such resources to a clock, so we make sure that the KMS driver enables
> these resources whenever a PLL is expected to be in use.
> 
> One place where we can't ensure the resource dependencies are met is when
> the clock framework tries to disable unused clocks. The KMS driver doesn't
> know when the clock framework calls the is_enabled clk_op, and hence can't
> enable interface clocks/power domains beforehand.
> 
> We set the CLK_IGNORE_UNUSED flag for PLL clocks for now. This needs to be
> revisited, since bootloaders can enable display, and we would want to
> disable the PLL clocks if there isn't a display driver using them.
> 
> Cc: Stephen Boyd <sboyd at codeaurora.org>
> Signed-off-by: Archit Taneja <architt at codeaurora.org>
> ---

Acked-by: Stephen Boyd <sboyd at codeaurora.org>

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