soc: realtek: ec: Implement power saving

Impelment RTS5912 power saving (heavy sleep)
Remove the power state of "suspend_to_ram"

Signed-off-by: Lin Yu-Cheng <[email protected]>

Author: JasonLin-RealTek

dts/arm/realtek/ec/rts5912.dtsi

@@ -12,6 +12,7 @@
 #include <zephyr/dt-bindings/pwm/pwm.h>
 #include <mem.h>
 #include <zephyr/dt-bindings/i2c/i2c.h>
+#include <freq.h>
 
 / {
 	cpus {
@@ -21,7 +22,7 @@
 		cpu0: cpu@0 {
 			compatible = "arm,cortex-m33f";
 			reg = <0>;
-			cpu-power-states = <&idle &suspend_to_ram>;
+			cpu-power-states = <&idle>;
 		};
 
 		power-states {
@@ -31,11 +32,6 @@
 				min-residency-us = <100000000>;
 			};
 
-			suspend_to_ram: suspend_to_ram {
-				compatible = "zephyr,power-state";
-				power-state-name = "suspend-to-ram";
-				min-residency-us = <250000000>;
-			};
 		};
 	};
 

soc/realtek/ec/rts5912/power.c

@@ -11,27 +11,12 @@
 #include <reg/reg_system.h>
 #include "device_power.h"
 
-#define RTS5912_SCCON_REG_BASE ((SYSTEM_Type *)(DT_REG_ADDR(DT_NODELABEL(sccon))))
-
 static void realtek_WFI(void)
 {
 	__DSB();
 	__WFI();
 }
 
-static void rts5912_light_sleep(void)
-{
-	SYSTEM_Type *sys_reg = RTS5912_SCCON_REG_BASE;
-
-	before_rts5912_sleep();
-
-	sys_reg->SLPCTRL &= ~SYSTEM_SLPCTRL_SLPMDSEL_Msk;
-
-	realtek_WFI();
-
-	after_rts5912_sleep();
-}
-
 static void rts5912_heavy_sleep(void)
 {
 	SYSTEM_Type *sys_reg = RTS5912_SCCON_REG_BASE;
@@ -50,7 +35,7 @@ static void rts5912_heavy_sleep(void)
 		sys_reg->SYSCLK |= SYSTEM_SYSCLK_SRC_Msk; /* Switch system clock to PLL */
 	}
 
-	sys_reg->SLPCTRL |= SYSTEM_SLPCTRL_SLPMDSEL_Msk; /* Heavy Sleep mode */
+	sys_reg->SLPCTRL |= (SYSTEM_SLPCTRL_SLPMDSEL_Msk | SYSTEM_SLPCTRL_GPIOWKEN_Msk);
 
 	realtek_WFI();
 
@@ -69,9 +54,6 @@ void pm_state_set(enum pm_state state, uint8_t substate_id)
 
 	switch (state) {
 	case PM_STATE_SUSPEND_TO_IDLE:
-		rts5912_light_sleep();
-		break;
-	case PM_STATE_SUSPEND_TO_RAM:
 		rts5912_heavy_sleep();
 		break;
 	default:
@@ -83,6 +65,4 @@ void pm_state_exit_post_ops(enum pm_state state, uint8_t substate_id)
 {
 	ARG_UNUSED(state);
 	ARG_UNUSED(substate_id);
-
-	irq_unlock(0);
 }

soc/realtek/ec/rts5912/reg/reg_system.h

@@ -334,4 +334,10 @@ typedef struct {
 
 #define RTS5912_SCCON_REG_BASE ((SYSTEM_Type *)(DT_REG_ADDR(DT_NODELABEL(sccon))))
 
+#define RTS5912_PUF_ADDRESS 0x40010800UL
+#define RTS5912_TRNG_OFFSET 0x600UL
+#define RTS5912_OTP_OFFSET  0x680UL
+#define RTS5912_CFG_PDSTB   (RTS5912_PUF_ADDRESS + RTS5912_OTP_OFFSET + 0x0024UL)
+#define RTS5912_RNG_RUN     (RTS5912_PUF_ADDRESS + RTS5912_TRNG_OFFSET + 0x0020UL)
+
 #endif /* ZEPHYR_SOC_REALTEK_RTS5912_REG_SYSTEM_H */

soc/realtek/ec/rts5912/soc.c

@@ -8,8 +8,10 @@
 #include <zephyr/kernel.h>
 #include <zephyr/device.h>
 #include <zephyr/init.h>
+#include <zephyr/pm/policy.h>
 #include <zephyr/logging/log.h>
 #include "debug_swj.h"
+#include <reg/reg_system.h>
 
 LOG_MODULE_REGISTER(soc, CONFIG_SOC_LOG_LEVEL);
 
@@ -28,15 +30,21 @@ bool z_arm_on_enter_cpu_idle(void)
  */
 void soc_early_init_hook(void)
 {
-	if (!IS_ENABLED(CONFIG_RTS5912_DEBUG_SWJ)) {
-		return;
-	}
-
+	SYSTEM_Type *sys_reg = RTS5912_SCCON_REG_BASE;
 	int ret;
 
 	/* Apply device related preinit configuration */
-	ret = swj_connector_init();
-	if (ret < 0) {
-		LOG_ERR("SWJ init failed");
+	if (IS_ENABLED(CONFIG_RTS5912_DEBUG_SWJ)) {
+		ret = swj_connector_init();
+		if (ret < 0) {
+			LOG_ERR("SWJ init failed %d", ret);
+		}
+	}
+
+	if (IS_ENABLED(CONFIG_PM)) {
+		/* turn off TRNG/ OTP/ LDO3 power */
+		sys_write32(0ul, RTS5912_RNG_RUN);
+		sys_write32(0ul, RTS5912_CFG_PDSTB);
+		sys_reg->LDOCTRL &= ~SYSTEM_LDOCTRL_LDO3EN_Msk;
 	}
 }