soc: arm: nxp: switch imxrt boards to use systick timer unless CONFIG_PM=y

Switch all imxrt boards to use the systick timer by default, and only
enable the GPT timer when using low power modes. This is desirable
because the systick has a higher resolution, but the GPT can run
while the core clock is gated, making it useful for low power modes.

Signed-off-by: Daniel DeGrasse <daniel.degrasse@nxp.com>

boards/arm/mimxrt1010_evk/mimxrt1010_evk.dts

@@ -104,9 +104,14 @@ zephyr_udc0: &usb1 {
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
+
+&systick {
+	status = "okay";
+};

boards/arm/mimxrt1015_evk/mimxrt1015_evk.dts

@@ -131,9 +131,14 @@ zephyr_udc0: &usb1 {
 	pinctrl-names = "default";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
+
+&systick {
+	status = "okay";
+};

boards/arm/mimxrt1020_evk/mimxrt1020_evk.dts

@@ -207,9 +207,14 @@ zephyr_udc0: &usb1 {
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
+
+&systick {
+	status = "okay";
+};

boards/arm/mimxrt1024_evk/mimxrt1024_evk.dts

@@ -165,13 +165,18 @@
 	pinctrl-names = "default";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 zephyr_udc0: &usb1 {
 	status = "okay";
 };

boards/arm/mimxrt1050_evk/mimxrt1050_evk.dts

@@ -282,9 +282,14 @@ zephyr_udc0: &usb1 {
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
+
+&systick {
+	status = "okay";
+};

boards/arm/mimxrt1060_evk/mimxrt1060_evk.dts

@@ -276,13 +276,18 @@ zephyr_udc0: &usb1 {
 	pinctrl-names = "default";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &iomuxcgpr {
 	status = "okay";
 };

boards/arm/mimxrt1064_evk/mimxrt1064_evk.dts

@@ -337,13 +337,18 @@ zephyr_udc0: &usb1 {
 	pinctrl-names = "default";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &itm {
 	pinctrl-0 = <&pinmux_swo>;
 	pinctrl-names = "default";

boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm4.dts

@@ -47,13 +47,18 @@
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &edma_lpsr0 {
 	status = "okay";
 };

boards/arm/mimxrt1160_evk/mimxrt1160_evk_cm7.dts

@@ -60,13 +60,18 @@
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &lpadc0 {
 	status = "okay";
 };

boards/arm/mimxrt1170_evk/mimxrt1170_evk_cm4.dts

@@ -47,13 +47,18 @@
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &sai1 {
 	status = "okay";
 };

boards/arm/mimxrt1170_evk/mimxrt1170_evk_cm7.dts

@@ -135,13 +135,18 @@
 	status = "okay";
 };
 
-/* Enable GPT for use as a hardware timer. This disables Cortex Systick.
+/* GPT and Systick are enabled. If power management is enabled, the GPT
- * to use systick, change this node from "gpt_hw_timer" to "systick"
+ * timer will be used instead of systick, as allows the core clock to
+ * be gated.
  */
 &gpt_hw_timer {
 	status = "okay";
 };
 
+&systick {
+	status = "okay";
+};
+
 &wdog1 {
 	status = "okay";
 };

drivers/timer/Kconfig.mcux_gpt

@@ -4,6 +4,7 @@
 config MCUX_GPT_TIMER
 	bool "MCUX GPT Event timer"
 	default y
+	depends on PM
 	depends on DT_HAS_NXP_GPT_HW_TIMER_ENABLED
 	select TICKLESS_CAPABLE
 	help

soc/arm/nxp_imx/rt/Kconfig.defconfig.mimxrt1166_cm4

@@ -14,4 +14,7 @@ config NUM_IRQS
 config GPIO
 	default y
 
+config SYS_CLOCK_HW_CYCLES_PER_SEC
+	default 240000000 if CORTEX_M_SYSTICK
+
 endif # SOC_MIMXRT1166_CM4

soc/arm/nxp_imx/rt/Kconfig.defconfig.mimxrt1166_cm7

@@ -14,4 +14,7 @@ config NUM_IRQS
 config GPIO
 	default y
 
+config SYS_CLOCK_HW_CYCLES_PER_SEC
+	default 600000000 if CORTEX_M_SYSTICK
+
 endif # SOC_MIMXRT1166_CM7

soc/arm/nxp_imx/rt/Kconfig.defconfig.series

@@ -47,6 +47,10 @@ config SYS_CLOCK_HW_CYCLES_PER_SEC
 	default $(dt_node_int_prop_int,$(DT_SYSCLK_PATH),clock-frequency) if SOC_SERIES_IMX_RT10XX && CORTEX_M_SYSTICK
 	default 32768 if MCUX_GPT_TIMER
 
+# Disable systick if using MCUX_GPT_TIMER, as they will conflict
+config CORTEX_M_SYSTICK
+	default n if MCUX_GPT_TIMER
+
 config PM_MCUX_GPC
 	default y if HAS_MCUX_GPC
 	depends on SOC_SERIES_IMX_RT11XX && PM