On 8/28/23 13:19, Chris Morgan wrote:

This is not accurate. The CCU's 32 kHz clock comes from the internal
RTC, whether you lie to the kernel about it or not. :)

If the external 32 kHz crystal represented by &osc32k really exists,
then I would expect the internal RTC to be accurate. At least the Linux
driver tries to switch to the external crystal.

If it's not using the external crystal... well, the V3s manual says
"Note: Internal 32kHz is divided from OSC24MHz". And there's no integer
factor of 24 MHz that gets you 32768 Hz, so that would explain the poor
accuracy. Even in that case, if you can't use the RTC as an RTC, it
should still be enabled in the DT, so the rest of the system can know
the actual OSC32K/LOSC clock frequency. Userspace should be able to deal
with the system having more than one RTC.

+
+&codec {
+	allwinner,audio-routing = "Speaker", "HP",
+				  "MIC1", "Mic",
+				  "Mic", "HBIAS";
+	allwinner,pa-gpios = <&pio 5 6 (GPIO_ACTIVE_HIGH | GPIO_PULL_UP)>; /* PF6 */
+	status = "okay";
+};
+
+&ehci {
+	status = "okay";
+};
+
+&i2c0 {
+	status = "okay";
+
+	gpio_expander: gpio@20 {
+		compatible = "nxp,pcal6416";
+		reg = <0x20>;
+		gpio-controller;
+		#gpio-cells = <2>;
+		#interrupt-cells = <2>;
+		interrupt-controller;
+		interrupt-parent = <&pio>;
+		interrupts = <1 3 IRQ_TYPE_EDGE_BOTH>; /* PB3/EINT3 */
+		vcc-supply = <&reg_vcc3v3>;
+	};
+
+	axp209: pmic@34 {
+		reg = <0x34>;
+		interrupt-parent = <&pio>;
+		interrupts = <1 5 IRQ_TYPE_EDGE_FALLING>; /* PB5/EINT5 */
+	};
+
+	pcf8563: rtc@51 {
+		compatible = "nxp,pcf8563";
+		reg = <0x51>;
+	};
+};
+
+#include "axp209.dtsi"
+
+&battery_power_supply {
+	status = "okay";
+};
+
+&mmc0 {
+	broken-cd;
+	bus-width = <4>;
+	disable-wp;
+	vmmc-supply = <&reg_vcc3v3>;
+	vqmmc-supply = <&reg_vcc3v3>;
+	status = "okay";
+};
+
+&ohci {
+	status = "okay";
+};
+
+&pio {
+	clocks = <&ccu CLK_BUS_PIO>, <&osc24M>, <&osc32k>;

The same concern applies here.

Regards,
Samuel

+	vcc-pb-supply = <&reg_vcc3v3>;
+	vcc-pc-supply = <&reg_vcc3v3>;
+	vcc-pf-supply = <&reg_vcc3v3>;
+	vcc-pg-supply = <&reg_vcc3v3>;
+
+	spi0_no_miso_pins: spi0-no-miso-pins {
+		pins = "PC1", "PC2", "PC3";
+		function = "spi0";
+	};
+};
+
+&pwm {
+	pinctrl-0 = <&pwm0_pin>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/* DCDC2 wired into vdd-cpu, vdd-sys, and vdd-ephy. */
+&reg_dcdc2 {
+	regulator-always-on;
+	regulator-max-microvolt = <1250000>;
+	regulator-min-microvolt = <1250000>;
+	regulator-name = "vdd-cpu";
+};
+
+/* DCDC3 wired into every 3.3v input that isn't the RTC. */
+&reg_dcdc3 {
+	regulator-always-on;
+	regulator-max-microvolt = <3300000>;
+	regulator-min-microvolt = <3300000>;
+	regulator-name = "vcc-io";
+};
+
+/*
+ * LDO1 wired into RTC, voltage is hard-wired at 3.3v and cannot be
+ * software modified. Note that setting voltage here to 3.3v for accuracy
+ * sake causes an issue with the driver that causes it to fail to probe
+ * because of a voltage constraint in the driver.
+ */
+&reg_ldo1 {
+	regulator-always-on;
+	regulator-name = "vcc-rtc";
+};
+
+/* LDO2 wired into VCC-PLL and audio codec. */
+&reg_ldo2 {
+	regulator-always-on;
+	regulator-max-microvolt = <3000000>;
+	regulator-min-microvolt = <3000000>;
+	regulator-name = "vcc-pll";
+};
+
+/* LDO3, LDO4, and LDO5 unused. */
+&reg_ldo3 {
+	status = "disabled";
+};
+
+&reg_ldo4 {
+	status = "disabled";
+};
+
+/* External RTC used instead, internal RTC runs fast. */
+&rtc {
+	status = "disabled";
+};
+
+&spi0 {
+	pinctrl-0 = <&spi0_no_miso_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	display@0 {
+		compatible = "saef,sftc154b", "panel-mipi-dbi-spi";
+		reg = <0>;
+		backlight = <&backlight>;
+		dc-gpios = <&pio 2 0 GPIO_ACTIVE_HIGH>; /* PC0 */
+		reset-gpios = <&pio 1 2 GPIO_ACTIVE_HIGH>; /* PB2 */
+		spi-max-frequency = <100000000>;
+
+		height-mm = <39>;
+		width-mm = <39>;
+
+		/* Set hb-porch to compensate for non-visible area */
+		panel-timing {
+			hactive = <240>;
+			vactive = <240>;
+			hback-porch = <80>;
+			vback-porch = <0>;
+			clock-frequency = <0>;
+			hfront-porch = <0>;
+			hsync-len = <0>;
+			vfront-porch = <0>;
+			vsync-len = <0>;
+		};
+	};
+};
+
+&uart0 {
+	pinctrl-0 = <&uart0_pb_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&usb_otg {
+	dr_mode = "otg";
+	status = "okay";
+};
+
+&usb_power_supply {
+	status = "okay";
+};
+
+&usbphy {
+	usb0_id_det-gpios = <&pio 6 5 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>; /* PG5 */
+	status = "okay";
+};