Re: [linux-sunxi] [PATCH 07/13] ARM: sun8i: h3: add display engine pipeline barebone

From: icenowy
Date: Wed Aug 02 2017 - 01:08:04 EST


å 2017-08-02 12:47ïJernej Åkrabec åéï
Hi Icenowy,

Dne torek, 01. avgust 2017 ob 15:12:58 CEST je Icenowy Zheng napisal(a):
As we have already the support for the DE2 on Allwinner H3, add the
display engine pipeline device tree nodes to its DTSI file.

The H5 pipeline has some differences and will be enabled later.

Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
---
arch/arm/boot/dts/sun8i-h3.dtsi | 170
++++++++++++++++++++++++++++++++++++++++ 1 file changed, 170 insertions(+)

diff --git a/arch/arm/boot/dts/sun8i-h3.dtsi
b/arch/arm/boot/dts/sun8i-h3.dtsi index b36f9f423c39..75ad7b65a7fc 100644
--- a/arch/arm/boot/dts/sun8i-h3.dtsi
+++ b/arch/arm/boot/dts/sun8i-h3.dtsi
@@ -41,6 +41,8 @@
*/

#include "sunxi-h3-h5.dtsi"
+#include <dt-bindings/clock/sun8i-de2.h>
+#include <dt-bindings/reset/sun8i-de2.h>

/ {
cpus {
@@ -72,6 +74,174 @@
};
};

+ de: display-engine {
+ compatible = "allwinner,sun8i-h3-display-engine";
+ allwinner,pipelines = <&mixer0>,
+ <&mixer1>;
+ status = "disabled";
+ };
+
+ 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>;
+ };

I believe Maxime ask you to use clk_set_rate() in the past:
http://lists.infradead.org/pipermail/linux-arm-kernel/2017-June/512909.html

Yes, but I think the frequency is still part of our configuration, not forced
by the hardware.

If we set it in the driver, why don't we set it to 300MHz?

(In fact for pipelines without TVE we can really use 300MHz for CLK_DE, and if
we do not want 4K we can even use lower frequency)


Regards,
Jernej