[PATCH 5/6] ARM: mstar: Add the external clocks to the base dsti

Daniel Palmer daniel at 0x0f.com
Sat Nov 14 08:50:43 EST 2020


All of the currently known MStar/SigmaStar ARMv7 SoCs have an "xtal"
clock input that is usually 24MHz and an "RTC xtal" that is usually 32KHz.

The xtal input has to be connected to something so it's enabled by default.

The MSC313 and MSC313E do not bring the RTC clock input out to the pins
so it's impossible to connect it. The SSC8336 does bring the input
out to the pins but it's not always actually connected to something.

The RTC node needs to always be present because in the future the nodes
for the clock muxes will refer to it even if it's not usable.

The RTC node is disabled by default and should be enabled at the board
level if the RTC input is wired up.

Signed-off-by: Daniel Palmer <daniel at 0x0f.com>
---
 arch/arm/boot/dts/mstar-v7.dtsi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/arch/arm/boot/dts/mstar-v7.dtsi b/arch/arm/boot/dts/mstar-v7.dtsi
index 81369bc07f78..6749d421dbf4 100644
--- a/arch/arm/boot/dts/mstar-v7.dtsi
+++ b/arch/arm/boot/dts/mstar-v7.dtsi
@@ -46,6 +46,21 @@ pmu: pmu {
 		interrupt-affinity = <&cpu0>;
 	};
 
+	clocks: clocks {
+		xtal: xtal {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <24000000>;
+		};
+
+		rtc_xtal: rtc_xtal {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <32768>;
+			status = "disabled";
+		};
+	};
+
 	soc: soc {
 		compatible = "simple-bus";
 		#address-cells = <1>;
-- 
2.29.2




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