diff --git a/lib/librte_power/channel_commands.h b/lib/librte_power/channel_commands.h
index 33fd53a6d..ce587283c 100644
--- a/lib/librte_power/channel_commands.h
+++ b/lib/librte_power/channel_commands.h
@@ -15,6 +15,8 @@ extern "C" {
 /* Maximum number of channels per VM */
 #define CHANNEL_CMDS_MAX_VM_CHANNELS 64
 
+/* --- Incoming messages --- */
+
 /* Valid Commands */
 #define CPU_POWER               1
 #define CPU_POWER_CONNECT       2
@@ -29,10 +31,19 @@ extern "C" {
 #define CPU_POWER_ENABLE_TURBO  5
 #define CPU_POWER_DISABLE_TURBO 6
 
+/* CPU Power Queries */
+#define CPU_POWER_QUERY_FREQ_LIST  7
+#define CPU_POWER_QUERY_FREQ       8
+
+/* --- Outgoing messages --- */
+
 /* Generic Power Command Response */
 #define CPU_POWER_CMD_ACK       1
 #define CPU_POWER_CMD_NACK      2
 
+/* CPU Power Query Responses */
+#define CPU_POWER_FREQ_LIST     3
+
 #define HOURS 24
 
 #define MAX_VFS 10
@@ -85,6 +96,16 @@ struct channel_packet {
 	struct t_boost_status t_boost_status;
 };
 
+struct channel_packet_freq_list {
+	uint64_t resource_id; /**< core_num, device */
+	uint32_t unit;        /**< scale down/up/min/max */
+	uint32_t command;     /**< Power, IO, etc */
+	char vm_name[VM_MAX_NAME_SZ];
+
+	uint32_t freq_list[MAX_VCPU_PER_VM];
+	uint8_t num_vcpu;
+};
+
 
 #ifdef __cplusplus
 }
diff --git a/lib/librte_power/guest_channel.c b/lib/librte_power/guest_channel.c
index 888423891..439cd2f38 100644
--- a/lib/librte_power/guest_channel.c
+++ b/lib/librte_power/guest_channel.c
@@ -129,13 +129,15 @@ int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
 	return guest_channel_send_msg(pkt, lcore_id);
 }
 
-int power_guest_channel_read_msg(struct channel_packet *pkt,
-			unsigned int lcore_id)
+int power_guest_channel_read_msg(void *pkt,
+		size_t pkt_len,
+		unsigned int lcore_id)
 {
 	int ret;
 	struct pollfd fds;
-	void *buffer = pkt;
-	int buffer_len = sizeof(*pkt);
+
+	if (pkt_len == 0 || pkt == NULL)
+		return -1;
 
 	fds.fd = global_fds[lcore_id];
 	fds.events = POLLIN;
@@ -161,29 +163,32 @@ int power_guest_channel_read_msg(struct channel_packet *pkt,
 		return -1;
 	}
 
-	while (buffer_len > 0) {
+	while (pkt_len > 0) {
 		ret = read(global_fds[lcore_id],
-				buffer, buffer_len);
+				pkt, pkt_len);
+
 		if (ret < 0) {
 			if (errno == EINTR)
 				continue;
 			return -1;
 		}
+
 		if (ret == 0) {
 			RTE_LOG(ERR, GUEST_CHANNEL, "Expected more data, but connection has been closed.\n");
 			return -1;
 		}
-		buffer = (char *)buffer + ret;
-		buffer_len -= ret;
+		pkt = (char *)pkt + ret;
+		pkt_len -= ret;
 	}
 
 	return 0;
 }
 
-int rte_power_guest_channel_receive_msg(struct channel_packet *pkt,
-			unsigned int lcore_id)
+int rte_power_guest_channel_receive_msg(void *pkt,
+		size_t pkt_len,
+		unsigned int lcore_id)
 {
-	return power_guest_channel_read_msg(pkt, lcore_id);
+	return power_guest_channel_read_msg(pkt, pkt_len, lcore_id);
 }
 
 void
diff --git a/lib/librte_power/guest_channel.h b/lib/librte_power/guest_channel.h
index 7c385df39..473901547 100644
--- a/lib/librte_power/guest_channel.h
+++ b/lib/librte_power/guest_channel.h
@@ -17,6 +17,7 @@ extern "C" {
  *
  * @param path
  *  The path to the serial device on the filesystem
+ *
  * @param lcore_id
  *  lcore_id.
  *
@@ -73,7 +74,11 @@ int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
  * from the host endpoint.
  *
  * @param pkt
- *  Pointer to a populated struct channel_packet
+ *  Pointer to channel_packet or
+ *  channel_packet_freq_list struct.
+ *
+ * @param pkt_len
+ *  Size of expected data packet.
  *
  * @param lcore_id
  *  lcore_id.
@@ -82,7 +87,8 @@ int rte_power_guest_channel_send_msg(struct channel_packet *pkt,
  *  - 0 on success.
  *  - Negative on error.
  */
-int power_guest_channel_read_msg(struct channel_packet *pkt,
+int power_guest_channel_read_msg(void *pkt,
+		size_t pkt_len,
 		unsigned int lcore_id);
 
 /**
@@ -90,7 +96,11 @@ int power_guest_channel_read_msg(struct channel_packet *pkt,
  * from the host endpoint.
  *
  * @param pkt
- *  Pointer to a populated struct channel_packet
+ *  Pointer to channel_packet or
+ *  channel_packet_freq_list struct.
+ *
+ * @param pkt_len
+ *  Size of expected data packet.
  *
  * @param lcore_id
  *  lcore_id.
@@ -100,8 +110,9 @@ int power_guest_channel_read_msg(struct channel_packet *pkt,
  *  - Negative on error.
  */
 int __rte_experimental
-rte_power_guest_channel_receive_msg(struct channel_packet *pkt,
-			unsigned int lcore_id);
+rte_power_guest_channel_receive_msg(void *pkt,
+		size_t pkt_len,
+		unsigned int lcore_id);
 
 #ifdef __cplusplus
 }
