在 2017-06-07 17:42，Maxime Ripard 写道：

On Mon, Jun 05, 2017 at 12:01:48AM +0800, Icenowy Zheng wrote:

quoted

+	soc {
+		display_clocks: clock@1000000 {
+			compatible = "allwinner,sun8i-a83t-de2-clk";
+			reg = <0x01000000 0x100000>;
+			clocks = <&ccu CLK_BUS_DE>,
+				 <&ccu CLK_DE>;
+			clock-names = "bus",
+				      "mod";
+			resets = <&ccu RST_BUS_DE>;
+			#clock-cells = <1>;
+			#reset-cells = <1>;
+			assigned-clocks = <&ccu CLK_DE>;
+			assigned-clock-parents = <&ccu CLK_PLL_DE>;
+			assigned-clock-rates = <432000000>;
+		};

We discussed that already a few times, but there's no reason to do
so. If you need a downstream clock at a particular rate, call
clk_set_rate on it, period.

Whether its parent will be coming from PLL_DE or some other more
appriopriate clock is not relevant and doesn't make any difference.

The clock framework is not so smart to deal with these infomations:
- CLK_PLL_PERIPH should always be 600MHz
- CLK_TVE should always be 216MHz
- CLK_DE (in fact CLK_MIXER{0,1}) should be larger than 300MHz (for 4K)

So we have to specify CLK_DE to be 432MHz, and then it will set
CLK_PLL_DE to this value, then the CLK_TVE can be set to 216MHz with
divider 2.

For DE there's no a real hardware block clock requirement, set it to

=300MHz is for 4K output support.

Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

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