Hi Paul,
On 2020-04-26 5:56 a.m., Paul Cercueil wrote:
Le ven. 24 avril 2020 à 22:34, H. Nikolaus Schaller hns@goldelico.com a écrit :
From: Jonathan Bakker xc-racer2@live.ca
All s5pv210 devices have a PowerVR SGX 540 (revision 120) attached.
There is no external regulator for it so it can be enabled by default.
Signed-off-by: Jonathan Bakker xc-racer2@live.ca Signed-off-by: H. Nikolaus Schaller hns@goldelico.com
arch/arm/boot/dts/s5pv210.dtsi | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/arch/arm/boot/dts/s5pv210.dtsi b/arch/arm/boot/dts/s5pv210.dtsi index 2ad642f51fd9..abbdda205c1b 100644 --- a/arch/arm/boot/dts/s5pv210.dtsi +++ b/arch/arm/boot/dts/s5pv210.dtsi @@ -512,6 +512,19 @@ vic3: interrupt-controller@f2300000 { #interrupt-cells = <1>; };
+ gpu: gpu@f3000000 { + compatible = "samsung,s5pv210-sgx540-120"; + reg = <0xf3000000 0x10000>; + interrupt-parent = <&vic2>; + interrupts = <10>; + clock-names = "core"; + clocks = <&clocks CLK_G3D>;
+ assigned-clocks = <&clocks MOUT_G3D>, <&clocks DOUT_G3D>; + assigned-clock-rates = <0>, <66700000>; + assigned-clock-parents = <&clocks MOUT_MPLL>;
What are these clocks for, and why are they reparented / reclocked?
Shouldn't they be passed to 'clocks' as well?
-Paul
The G3D clock system can have multiple parents, and for stable operation it's recommended to use the MPLL clock as the parent (which in turn is actually a mux as well). MOUT_G3D is simply the mux for CLK_G3D (SGX core clock), DOUT_G3D is the divider. DOUT_G3D could equally be CLK_G3D (and probably should be, for readability) as CLK_G3D is simply the gate and DOUT_G3D is the divider for it.
The SGX clock layout on S5PV210 looks something like this:
MOUT_MPLL -----------> MOUT_G3D ---> DOUT_G3D ---> CLK_G3D (selectable parent clock) (mux) ---> (divider) ---> (gate)
This is fairly common for older Samsung SoCs, eg having a look at arch/arm/boot/dts/exynos4210-universal_c210.dts you can see that the FIMC clocks are parented to MPLL and have a rate set.
+ };
fimd: fimd@f8000000 { compatible = "samsung,s5pv210-fimd"; interrupt-parent = <&vic2>; -- 2.25.1
Thanks, Jonathan