NXP imx95 add basic pm support

drivers/firmware/scmi/clk.c

@@ -6,6 +6,7 @@
 
 #include <zephyr/drivers/firmware/scmi/clk.h>
 #include <string.h>
+#include <zephyr/kernel.h>
 
 /* TODO: if extended attributes are supported this should be moved
  * to the header file so that users will have access to it.
@@ -57,7 +58,7 @@ int scmi_clock_rate_get(struct scmi_protocol *proto,
 	reply.len = sizeof(reply_buffer);
 	reply.content = &reply_buffer;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -98,7 +99,7 @@ int scmi_clock_rate_set(struct scmi_protocol *proto, struct scmi_clock_rate_conf
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -134,7 +135,7 @@ int scmi_clock_parent_get(struct scmi_protocol *proto, uint32_t clk_id, uint32_t
 	reply.len = sizeof(reply_buffer);
 	reply.content = &reply_buffer;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -172,7 +173,7 @@ int scmi_clock_parent_set(struct scmi_protocol *proto, uint32_t clk_id, uint32_t
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -223,7 +224,7 @@ int scmi_clock_config_set(struct scmi_protocol *proto,
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -260,7 +261,7 @@ int scmi_clock_protocol_attributes(struct scmi_protocol *proto, uint32_t *attrib
 	reply.len = sizeof(reply_buffer);
 	reply.content = &reply_buffer;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}

drivers/firmware/scmi/core.c

@@ -8,6 +8,7 @@
 #include <zephyr/drivers/firmware/scmi/transport.h>
 #include <zephyr/logging/log.h>
 #include <zephyr/device.h>
+#include "mailbox.h"
 
 LOG_MODULE_REGISTER(scmi_core);
 
@@ -87,12 +88,34 @@ static int scmi_core_setup_chan(const struct device *transport,
 	return 0;
 }
 
+static int scmi_interrupt_enable(struct scmi_channel *chan, bool enable)
+{
+	struct scmi_mbox_channel *mbox_chan;
+	struct mbox_dt_spec *tx_reply;
+	bool compInt;
+
+	mbox_chan = chan->data;
+	compInt = enable ? SCMI_SHMEM_CHAN_FLAG_IRQ_BIT : 0;
+
+	if (mbox_chan->tx_reply.dev) {
+		tx_reply = &mbox_chan->tx_reply;
+	} else {
+		tx_reply = &mbox_chan->tx;
+	}
+
+	/* re-set completion interrupt */
+	scmi_shmem_update_flags(mbox_chan->shmem, SCMI_SHMEM_CHAN_FLAG_IRQ_BIT, compInt);
+
+	return mbox_set_enabled_dt(tx_reply, enable);
+}
+
 static int scmi_send_message_pre_kernel(struct scmi_protocol *proto,
 					struct scmi_message *msg,
 					struct scmi_message *reply)
 {
 	int ret;
 
+	scmi_interrupt_enable(proto->tx, false);
 	ret = scmi_transport_send_message(proto->transport, proto->tx, msg);
 	if (ret < 0) {
 		return ret;
@@ -113,6 +136,7 @@ static int scmi_send_message_pre_kernel(struct scmi_protocol *proto,
 		return ret;
 	}
 
+	scmi_interrupt_enable(proto->tx, true);
 	return ret;
 }
 
@@ -159,7 +183,7 @@ static int scmi_send_message_post_kernel(struct scmi_protocol *proto,
 }
 
 int scmi_send_message(struct scmi_protocol *proto, struct scmi_message *msg,
-		      struct scmi_message *reply)
+		      struct scmi_message *reply, bool pre_kernel)
 {
 	if (!proto->tx) {
 		return -ENODEV;
@@ -169,7 +193,7 @@ int scmi_send_message(struct scmi_protocol *proto, struct scmi_message *msg,
 		return -EINVAL;
 	}
 
-	if (k_is_pre_kernel()) {
+	if (pre_kernel) {
 		return scmi_send_message_pre_kernel(proto, msg, reply);
 	} else {
 		return scmi_send_message_post_kernel(proto, msg, reply);

drivers/firmware/scmi/nxp/cpu.c

@@ -6,6 +6,7 @@
 
 #include <string.h>
 #include <zephyr/drivers/firmware/scmi/nxp/cpu.h>
+#include <zephyr/kernel.h>
 
 DT_SCMI_PROTOCOL_DEFINE_NODEV(DT_INST(0, nxp_scmi_cpu), NULL);
 
@@ -33,7 +34,43 @@ int scmi_cpu_sleep_mode_set(struct scmi_cpu_sleep_mode_config *cfg)
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, true);
+	if (ret < 0) {
+		return ret;
+	}
+
+	if (status != SCMI_SUCCESS) {
+		return scmi_status_to_errno(status);
+	}
+
+	return 0;
+}
+
+int scmi_cpu_pd_lpm_set(struct scmi_cpu_pd_lpm_config *cfg)
+{
+	struct scmi_protocol *proto = &SCMI_PROTOCOL_NAME(SCMI_PROTOCOL_CPU_DOMAIN);
+	struct scmi_message msg, reply;
+	int status, ret;
+
+	/* sanity checks */
+	if (!proto || !cfg) {
+		return -EINVAL;
+	}
+
+	if (proto->id != SCMI_PROTOCOL_CPU_DOMAIN) {
+		return -EINVAL;
+	}
+
+	msg.hdr = SCMI_MESSAGE_HDR_MAKE(SCMI_CPU_DOMAIN_MSG_CPU_PD_LPM_CONFIG_SET, SCMI_COMMAND,
+					proto->id, 0x0);
+	msg.len = sizeof(*cfg);
+	msg.content = cfg;
+
+	reply.hdr = msg.hdr;
+	reply.len = sizeof(status);
+	reply.content = &status;
+
+	ret = scmi_send_message(proto, &msg, &reply, true);
 	if (ret < 0) {
 		return ret;
 	}

drivers/firmware/scmi/pinctrl.c

@@ -5,6 +5,7 @@
  */
 
 #include <zephyr/drivers/firmware/scmi/pinctrl.h>
+#include <zephyr/kernel.h>
 
 DT_SCMI_PROTOCOL_DEFINE_NODEV(DT_INST(0, arm_scmi_pinctrl), NULL);
 
@@ -50,7 +51,7 @@ int scmi_pinctrl_settings_configure(struct scmi_pinctrl_settings *settings)
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}

drivers/firmware/scmi/power.c

@@ -6,6 +6,7 @@
 
 #include <zephyr/drivers/firmware/scmi/power.h>
 #include <string.h>
+#include <zephyr/kernel.h>
 
 DT_SCMI_PROTOCOL_DEFINE_NODEV(DT_INST(0, arm_scmi_power), NULL);
 
@@ -39,7 +40,7 @@ int scmi_power_state_get(uint32_t domain_id, uint32_t *power_state)
 	reply.len = sizeof(reply_buffer);
 	reply.content = &reply_buffer;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}
@@ -82,7 +83,7 @@ int scmi_power_state_set(struct scmi_power_state_config *cfg)
 	reply.len = sizeof(status);
 	reply.content = &status;
 
-	ret = scmi_send_message(proto, &msg, &reply);
+	ret = scmi_send_message(proto, &msg, &reply, k_is_pre_kernel());
 	if (ret < 0) {
 		return ret;
 	}

dts/arm/nxp/nxp_imx95_m7.dtsi

@@ -15,9 +15,10 @@
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-		cpu@0 {
+		cpu0: cpu@0 {
 			device_type = "cpu";
 			compatible = "arm,cortex-m7";
+			cpu-power-states = <&wait &stop &suspend>;
 			reg = <0>;
 
 			#address-cells = <1>;
@@ -27,6 +28,30 @@
 				compatible = "arm,armv7m-mpu";
 				reg = <0xe000ed90 0x40>;
 			};
+
+		};
+
+		power-states {
+			wait: power-state-wait {
+				compatible = "zephyr,power-state";
+				power-state-name = "runtime-idle";
+				min-residency-us = <100>;
+				exit-latency-us = <50>;
+			};
+
+			stop: power-state-stop {
+				compatible = "zephyr,power-state";
+				power-state-name = "suspend-to-idle";
+				min-residency-us = <1000>;
+				exit-latency-us = <200>;
+			};
+
+			suspend: power-state-suspend {
+				compatible = "zephyr,power-state";
+				power-state-name = "standby";
+				min-residency-us = <5000>;
+				exit-latency-us = <1000>;
+			};
 		};
 	};
 

include/zephyr/drivers/firmware/scmi/nxp/cpu.h

@@ -21,6 +21,8 @@
 
 #define SCMI_PROTOCOL_CPU_DOMAIN 130
 
+#define SCMI_CPU_MAX_PDCONFIGS_T 7U
+
 /**
  * @struct scmi_cpu_sleep_mode_config
  *
@@ -33,6 +35,23 @@ struct scmi_cpu_sleep_mode_config {
 	uint32_t sleep_mode;
 };
 
+struct scmi_pd_lpm_settings {
+	uint32_t domainId;
+	uint32_t lpmSetting;
+	uint32_t retMask;
+};
+
+/**
+ * @struct scmi_cpu_pd_lpm_config
+ *
+ * @brief Describes cpu power domain low power mode setting
+ */
+struct scmi_cpu_pd_lpm_config {
+	uint32_t cpu_id;
+	uint32_t num_cfg;
+	struct scmi_pd_lpm_settings cfgs[SCMI_CPU_MAX_PDCONFIGS_T];
+};
+
 /**
  * @brief CPU domain protocol command message IDs
  */
@@ -64,4 +83,14 @@ enum scmi_cpu_domain_message {
  */
 int scmi_cpu_sleep_mode_set(struct scmi_cpu_sleep_mode_config *cfg);
 
+/**
+ * @brief Send the SCMI_CPU_DOMAIN_MSG_CPU_PD_LPM_CONFIG_SET command and get its reply
+ *
+ * @param cfg pointer to structure containing configuration
+ * to be set
+ *
+ * @retval 0 if successful
+ * @retval negative errno if failure
+ */
+int scmi_cpu_pd_lpm_set(struct scmi_cpu_pd_lpm_config *cfg);
 #endif /* _INCLUDE_ZEPHYR_DRIVERS_FIRMWARE_SCMI_CPU_H_ */

include/zephyr/drivers/firmware/scmi/protocol.h

@@ -115,8 +115,10 @@ int scmi_status_to_errno(int scmi_status);
  *
  * @retval 0 if successful
  * @retval negative errno if failure
+ * @param pre_kernel current kernel state
  */
 int scmi_send_message(struct scmi_protocol *proto,
-		      struct scmi_message *msg, struct scmi_message *reply);
+		      struct scmi_message *msg, struct scmi_message *reply,
+		      bool pre_kernel);
 
 #endif /* _INCLUDE_ZEPHYR_DRIVERS_FIRMWARE_SCMI_PROTOCOL_H_ */

soc/nxp/imx/imx9/imx95/Kconfig

@@ -13,6 +13,7 @@ config SOC_MIMX9596_M7
 	select SOC_LATE_INIT_HOOK
 	select HAS_MCUX
 	select HAS_MCUX_CACHE
+	select HAS_PM
 
 config SOC_MIMX9596_A55
 	select ARM64

soc/nxp/imx/imx9/imx95/Kconfig.defconfig.mimx95.m7

@@ -50,5 +50,11 @@ config CACHE_MANAGEMENT
 
 config ETH_NXP_IMX_MSGINTR
 	default 2
+if PM
+# PM code that runs from the idle loop has a large
+# footprint. Hence increase the size when PM is enabled.
+config IDLE_STACK_SIZE
+	default 640
+endif
 
 endif # SOC_MIMX9596_M7