arm64: dts: exynos: gs101-oriole: configure simple-framebuffer

The bootloader configures the display hardware for a framebuffer at the
given address, let's add a simple-framebuffer node here until we get a
proper DRM driver.

This has several benefits since it's an OLED display:
* energy consumption goes down significantly, as it changes from white
  (as left by bootloader) to black (linux console), and we generally
  don't run out of battery anymore when plugged into a USB port
* less of a burn-in effect I assume
* phone stays cooler due to reduced energy consumption by display

Signed-off-by: André Draszik <andre.draszik@linaro.org>
Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://lore.kernel.org/r/20250117-gs101-simplefb-v4-2-a5b90ca2f917@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

diff --git a/arch/arm64/boot/dts/exynos/google/gs101-oriole.dts b/arch/arm64/boot/dts/exynos/google/gs101-oriole.dts
index e58881c61d53eaa9c9df95b874029d61ba23f11b..d3dd411c9bd0ce7902997fef10b14f3e66f45140 100644 (file)
--- a/arch/arm64/boot/dts/exynos/google/gs101-oriole.dts
+++ b/arch/arm64/boot/dts/exynos/google/gs101-oriole.dts
@@ -26,6 +26,16 @@
                /* Bootloader expects bootargs specified otherwise it crashes */
                bootargs = "";
                stdout-path = &serial_0;
+
+               /* Use display framebuffer as setup by bootloader */
+               framebuffer0: framebuffer-0 {
+                       compatible = "simple-framebuffer";
+                       memory-region = <&cont_splash_mem>;
+                       width = <1080>;
+                       height = <2400>;
+                       stride = <(1080 * 4)>;
+                       format = "a8r8g8b8";
+               };
        };
 
        gpio-keys {
@@ -69,6 +79,13 @@
                regulator-boot-on;
                enable-active-high;
        };
+
+       reserved-memory {
+               cont_splash_mem: splash@fac00000 {
+                       reg = <0x0 0xfac00000 (1080 * 2400 * 4)>;
+                       no-map;
+               };
+       };
 };
 
 &ext_24_5m {