drm/amd/display: Add Support for reg inbox0 for host->DMUB CMDs

[WHY]
DCN4+ supports a new register based mailbox for sending messages
from host to DMCUB. This mailbox supports 64 byte commands, which makes
it compatible with the same structure as the frame buffer based mailbox.

[HOW]
The intention for reg_inbox0 is to be slot in replacement for the frame
buffer based mailbox (Inbox1). It supports all of the required features:
- Supports all messages handled by FB Inbox1
- Supports multi command batching

Reviewed-by: Joshua Aberback <joshua.aberback@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 292 insertions, 135 deletions

diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
index e67f7c4784eb..731ca9b6a6cf 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.c
@@ -517,28 +517,69 @@ void dmub_dcn401_send_reg_inbox0_cmd_msg(struct dmub_srv *dmub,
 		union dmub_rb_cmd *cmd)
 {
 	uint32_t *dwords = (uint32_t *)cmd;
-
+	int32_t payload_size_bytes = cmd->cmd_common.header.payload_bytes;
+	uint32_t msg_index;
 	static_assert(sizeof(*cmd) == 64, "DMUB command size mismatch");
 
-	REG_WRITE(DMCUB_REG_INBOX0_MSG0, dwords[0]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG1, dwords[1]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG2, dwords[2]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG3, dwords[3]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG4, dwords[4]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG5, dwords[5]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG6, dwords[6]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG7, dwords[7]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG8, dwords[8]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG9, dwords[9]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG10, dwords[10]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG11, dwords[11]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG12, dwords[12]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG13, dwords[13]);
-	REG_WRITE(DMCUB_REG_INBOX0_MSG14, dwords[14]);
+	/* read remaining data based on payload size */
+	for (msg_index = 0; msg_index < 15; msg_index++) {
+		if (payload_size_bytes <= msg_index * 4) {
+			break;
+		}
+
+		switch (msg_index) {
+		case 0:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG0, dwords[msg_index + 1]);
+			break;
+		case 1:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG1, dwords[msg_index + 1]);
+			break;
+		case 2:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG2, dwords[msg_index + 1]);
+			break;
+		case 3:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG3, dwords[msg_index + 1]);
+			break;
+		case 4:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG4, dwords[msg_index + 1]);
+			break;
+		case 5:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG5, dwords[msg_index + 1]);
+			break;
+		case 6:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG6, dwords[msg_index + 1]);
+			break;
+		case 7:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG7, dwords[msg_index + 1]);
+			break;
+		case 8:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG8, dwords[msg_index + 1]);
+			break;
+		case 9:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG9, dwords[msg_index + 1]);
+			break;
+		case 10:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG10, dwords[msg_index + 1]);
+			break;
+		case 11:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG11, dwords[msg_index + 1]);
+			break;
+		case 12:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG12, dwords[msg_index + 1]);
+			break;
+		case 13:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG13, dwords[msg_index + 1]);
+			break;
+		case 14:
+			REG_WRITE(DMCUB_REG_INBOX0_MSG14, dwords[msg_index + 1]);
+			break;
+		}
+	}
+
 	/* writing to INBOX RDY register will trigger DMUB REG INBOX0 RDY
 	 * interrupt.
 	 */
-	REG_WRITE(DMCUB_REG_INBOX0_RDY, dwords[15]);
+	REG_WRITE(DMCUB_REG_INBOX0_RDY, dwords[0]);
 }
 
 uint32_t dmub_dcn401_read_reg_inbox0_rsp_int_status(struct dmub_srv *dmub)
@@ -556,30 +597,39 @@ void dmub_dcn401_read_reg_inbox0_cmd_rsp(struct dmub_srv *dmub,
 
 	static_assert(sizeof(*cmd) == 64, "DMUB command size mismatch");
 
-	dwords[0] = REG_READ(DMCUB_REG_INBOX0_MSG0);
-	dwords[1] = REG_READ(DMCUB_REG_INBOX0_MSG1);
-	dwords[2] = REG_READ(DMCUB_REG_INBOX0_MSG2);
-	dwords[3] = REG_READ(DMCUB_REG_INBOX0_MSG3);
-	dwords[4] = REG_READ(DMCUB_REG_INBOX0_MSG4);
-	dwords[5] = REG_READ(DMCUB_REG_INBOX0_MSG5);
-	dwords[6] = REG_READ(DMCUB_REG_INBOX0_MSG6);
-	dwords[7] = REG_READ(DMCUB_REG_INBOX0_MSG7);
-	dwords[8] = REG_READ(DMCUB_REG_INBOX0_MSG8);
-	dwords[9] = REG_READ(DMCUB_REG_INBOX0_MSG9);
-	dwords[10] = REG_READ(DMCUB_REG_INBOX0_MSG10);
-	dwords[11] = REG_READ(DMCUB_REG_INBOX0_MSG11);
-	dwords[12] = REG_READ(DMCUB_REG_INBOX0_MSG12);
-	dwords[13] = REG_READ(DMCUB_REG_INBOX0_MSG13);
-	dwords[14] = REG_READ(DMCUB_REG_INBOX0_MSG14);
-	dwords[15] = REG_READ(DMCUB_REG_INBOX0_RSP);
+	dwords[0] = REG_READ(DMCUB_REG_INBOX0_RSP);
+	dwords[1] = REG_READ(DMCUB_REG_INBOX0_MSG0);
+	dwords[2] = REG_READ(DMCUB_REG_INBOX0_MSG1);
+	dwords[3] = REG_READ(DMCUB_REG_INBOX0_MSG2);
+	dwords[4] = REG_READ(DMCUB_REG_INBOX0_MSG3);
+	dwords[5] = REG_READ(DMCUB_REG_INBOX0_MSG4);
+	dwords[6] = REG_READ(DMCUB_REG_INBOX0_MSG5);
+	dwords[7] = REG_READ(DMCUB_REG_INBOX0_MSG6);
+	dwords[8] = REG_READ(DMCUB_REG_INBOX0_MSG7);
+	dwords[9] = REG_READ(DMCUB_REG_INBOX0_MSG8);
+	dwords[10] = REG_READ(DMCUB_REG_INBOX0_MSG9);
+	dwords[11] = REG_READ(DMCUB_REG_INBOX0_MSG10);
+	dwords[12] = REG_READ(DMCUB_REG_INBOX0_MSG11);
+	dwords[13] = REG_READ(DMCUB_REG_INBOX0_MSG12);
+	dwords[14] = REG_READ(DMCUB_REG_INBOX0_MSG13);
+	dwords[15] = REG_READ(DMCUB_REG_INBOX0_MSG14);
 }
 
 void dmub_dcn401_write_reg_inbox0_rsp_int_ack(struct dmub_srv *dmub)
 {
 	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_INBOX0_RSP_INT_ACK, 1);
+}
+
+void dmub_dcn401_clear_reg_inbox0_rsp_int_ack(struct dmub_srv *dmub)
+{
 	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_INBOX0_RSP_INT_ACK, 0);
 }
 
+void dmub_dcn401_enable_reg_inbox0_rsp_int(struct dmub_srv *dmub, bool enable)
+{
+	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_INBOX0_RSP_INT_EN, enable ? 1:0);
+}
+
 void dmub_dcn401_write_reg_outbox0_rdy_int_ack(struct dmub_srv *dmub)
 {
 	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_OUTBOX0_RDY_INT_ACK, 1);
@@ -604,11 +654,6 @@ uint32_t dmub_dcn401_read_reg_outbox0_rsp_int_status(struct dmub_srv *dmub)
 	return status;
 }
 
-void dmub_dcn401_enable_reg_inbox0_rsp_int(struct dmub_srv *dmub, bool enable)
-{
-	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_INBOX0_RSP_INT_EN, enable ? 1:0);
-}
-
 void dmub_dcn401_enable_reg_outbox0_rdy_int(struct dmub_srv *dmub, bool enable)
 {
 	REG_UPDATE(HOST_INTERRUPT_CSR, HOST_REG_OUTBOX0_RDY_INT_EN, enable ? 1:0);
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.h b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.h
index c35be52676f6..88c3a44d67d9 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.h
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn401.h
@@ -277,11 +277,13 @@ uint32_t dmub_dcn401_read_reg_inbox0_rsp_int_status(struct dmub_srv *dmub);
 void dmub_dcn401_read_reg_inbox0_cmd_rsp(struct dmub_srv *dmub,
 		union dmub_rb_cmd *cmd);
 void dmub_dcn401_write_reg_inbox0_rsp_int_ack(struct dmub_srv *dmub);
+void dmub_dcn401_clear_reg_inbox0_rsp_int_ack(struct dmub_srv *dmub);
+void dmub_dcn401_enable_reg_inbox0_rsp_int(struct dmub_srv *dmub, bool enable);
+
 void dmub_dcn401_write_reg_outbox0_rdy_int_ack(struct dmub_srv *dmub);
 void dmub_dcn401_read_reg_outbox0_msg(struct dmub_srv *dmub, uint32_t *msg);
 void dmub_dcn401_write_reg_outbox0_rsp(struct dmub_srv *dmub, uint32_t *msg);
 uint32_t dmub_dcn401_read_reg_outbox0_rsp_int_status(struct dmub_srv *dmub);
-void dmub_dcn401_enable_reg_inbox0_rsp_int(struct dmub_srv *dmub, bool enable);
 void dmub_dcn401_enable_reg_outbox0_rdy_int(struct dmub_srv *dmub, bool enable);
 uint32_t dmub_dcn401_read_reg_outbox0_rdy_int_status(struct dmub_srv *dmub);
 
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
index 0a2285540daf..713576a1f6fa 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
@@ -157,6 +157,9 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 {
 	struct dmub_srv_hw_funcs *funcs = &dmub->hw_funcs;
 
+	/* default to specifying now inbox type */
+	enum dmub_inbox_cmd_interface_type default_inbox_type = DMUB_CMD_INTERFACE_DEFAULT;
+
 	switch (asic) {
 	case DMUB_ASIC_DCN20:
 	case DMUB_ASIC_DCN21:
@@ -353,7 +356,7 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 
 			funcs->init_reg_offsets = dmub_srv_dcn35_regs_init;
 			if (asic == DMUB_ASIC_DCN351)
-                                funcs->init_reg_offsets = dmub_srv_dcn351_regs_init;
+				funcs->init_reg_offsets = dmub_srv_dcn351_regs_init;
 			if (asic == DMUB_ASIC_DCN36)
 				funcs->init_reg_offsets = dmub_srv_dcn36_regs_init;
 
@@ -395,10 +398,15 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 
 		funcs->get_current_time = dmub_dcn401_get_current_time;
 		funcs->get_diagnostic_data = dmub_dcn401_get_diagnostic_data;
+
 		funcs->send_reg_inbox0_cmd_msg = dmub_dcn401_send_reg_inbox0_cmd_msg;
 		funcs->read_reg_inbox0_rsp_int_status = dmub_dcn401_read_reg_inbox0_rsp_int_status;
 		funcs->read_reg_inbox0_cmd_rsp = dmub_dcn401_read_reg_inbox0_cmd_rsp;
 		funcs->write_reg_inbox0_rsp_int_ack = dmub_dcn401_write_reg_inbox0_rsp_int_ack;
+		funcs->clear_reg_inbox0_rsp_int_ack = dmub_dcn401_clear_reg_inbox0_rsp_int_ack;
+		funcs->enable_reg_inbox0_rsp_int = dmub_dcn401_enable_reg_inbox0_rsp_int;
+		default_inbox_type = DMUB_CMD_INTERFACE_FB; // still default to FB for now
+
 		funcs->write_reg_outbox0_rdy_int_ack = dmub_dcn401_write_reg_outbox0_rdy_int_ack;
 		funcs->read_reg_outbox0_msg = dmub_dcn401_read_reg_outbox0_msg;
 		funcs->write_reg_outbox0_rsp = dmub_dcn401_write_reg_outbox0_rsp;
@@ -411,6 +419,20 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 		return false;
 	}
 
+	/* set default inbox type if not overriden */
+	if (dmub->inbox_type == DMUB_CMD_INTERFACE_DEFAULT) {
+		if (default_inbox_type != DMUB_CMD_INTERFACE_DEFAULT) {
+			/* use default inbox type as specified by DCN rev */
+			dmub->inbox_type = default_inbox_type;
+		} else if (funcs->send_reg_inbox0_cmd_msg) {
+			/* prefer reg as default inbox type if present */
+			dmub->inbox_type = DMUB_CMD_INTERFACE_REG;
+		} else {
+			/* use fb as fallback */
+			dmub->inbox_type = DMUB_CMD_INTERFACE_FB;
+		}
+	}
+
 	return true;
 }
 
@@ -426,6 +448,7 @@ enum dmub_status dmub_srv_create(struct dmub_srv *dmub,
 	dmub->asic = params->asic;
 	dmub->fw_version = params->fw_version;
 	dmub->is_virtual = params->is_virtual;
+	dmub->inbox_type = params->inbox_type;
 
 	/* Setup asic dependent hardware funcs. */
 	if (!dmub_srv_hw_setup(dmub, params->asic)) {
@@ -695,7 +718,7 @@ enum dmub_status dmub_srv_hw_init(struct dmub_srv *dmub,
 	inbox1.base = cw4.region.base;
 	inbox1.top = cw4.region.base + DMUB_RB_SIZE;
 	outbox1.base = inbox1.top;
-	outbox1.top = cw4.region.top;
+	outbox1.top = inbox1.top + DMUB_RB_SIZE;
 
 	cw5.offset.quad_part = tracebuff_fb->gpu_addr;
 	cw5.region.base = DMUB_CW5_BASE;
@@ -737,7 +760,7 @@ enum dmub_status dmub_srv_hw_init(struct dmub_srv *dmub,
 	rb_params.ctx = dmub;
 	rb_params.base_address = mail_fb->cpu_addr;
 	rb_params.capacity = DMUB_RB_SIZE;
-	dmub_rb_init(&dmub->inbox1_rb, &rb_params);
+	dmub_rb_init(&dmub->inbox1.rb, &rb_params);
 
 	// Initialize outbox1 ring buffer
 	rb_params.ctx = dmub;
@@ -768,27 +791,6 @@ enum dmub_status dmub_srv_hw_init(struct dmub_srv *dmub,
 	return DMUB_STATUS_OK;
 }
 
-enum dmub_status dmub_srv_sync_inbox1(struct dmub_srv *dmub)
-{
-	if (!dmub->sw_init)
-		return DMUB_STATUS_INVALID;
-
-	if (dmub->hw_funcs.get_inbox1_rptr && dmub->hw_funcs.get_inbox1_wptr) {
-		uint32_t rptr = dmub->hw_funcs.get_inbox1_rptr(dmub);
-		uint32_t wptr = dmub->hw_funcs.get_inbox1_wptr(dmub);
-
-		if (rptr > dmub->inbox1_rb.capacity || wptr > dmub->inbox1_rb.capacity) {
-			return DMUB_STATUS_HW_FAILURE;
-		} else {
-			dmub->inbox1_rb.rptr = rptr;
-			dmub->inbox1_rb.wrpt = wptr;
-			dmub->inbox1_last_wptr = dmub->inbox1_rb.wrpt;
-		}
-	}
-
-	return DMUB_STATUS_OK;
-}
-
 enum dmub_status dmub_srv_hw_reset(struct dmub_srv *dmub)
 {
 	if (!dmub->sw_init)
@@ -799,8 +801,13 @@ enum dmub_status dmub_srv_hw_reset(struct dmub_srv *dmub)
 
 	/* mailboxes have been reset in hw, so reset the sw state as well */
 	dmub->inbox1_last_wptr = 0;
-	dmub->inbox1_rb.wrpt = 0;
-	dmub->inbox1_rb.rptr = 0;
+	dmub->inbox1.rb.wrpt = 0;
+	dmub->inbox1.rb.rptr = 0;
+	dmub->inbox1.num_reported = 0;
+	dmub->inbox1.num_submitted = 0;
+	dmub->reg_inbox0.num_reported = 0;
+	dmub->reg_inbox0.num_submitted = 0;
+	dmub->reg_inbox0.is_pending = 0;
 	dmub->outbox0_rb.wrpt = 0;
 	dmub->outbox0_rb.rptr = 0;
 	dmub->outbox1_rb.wrpt = 0;
@@ -811,7 +818,7 @@ enum dmub_status dmub_srv_hw_reset(struct dmub_srv *dmub)
 	return DMUB_STATUS_OK;
 }
 
-enum dmub_status dmub_srv_cmd_queue(struct dmub_srv *dmub,
+enum dmub_status dmub_srv_fb_cmd_queue(struct dmub_srv *dmub,
 				    const union dmub_rb_cmd *cmd)
 {
 	if (!dmub->hw_init)
@@ -820,18 +827,20 @@ enum dmub_status dmub_srv_cmd_queue(struct dmub_srv *dmub,
 	if (dmub->power_state != DMUB_POWER_STATE_D0)
 		return DMUB_STATUS_POWER_STATE_D3;
 
-	if (dmub->inbox1_rb.rptr > dmub->inbox1_rb.capacity ||
-	    dmub->inbox1_rb.wrpt > dmub->inbox1_rb.capacity) {
+	if (dmub->inbox1.rb.rptr > dmub->inbox1.rb.capacity ||
+	    dmub->inbox1.rb.wrpt > dmub->inbox1.rb.capacity) {
 		return DMUB_STATUS_HW_FAILURE;
 	}
 
-	if (dmub_rb_push_front(&dmub->inbox1_rb, cmd))
+	if (dmub_rb_push_front(&dmub->inbox1.rb, cmd)) {
+		dmub->inbox1.num_submitted++;
 		return DMUB_STATUS_OK;
+	}
 
 	return DMUB_STATUS_QUEUE_FULL;
 }
 
-enum dmub_status dmub_srv_cmd_execute(struct dmub_srv *dmub)
+enum dmub_status dmub_srv_fb_cmd_execute(struct dmub_srv *dmub)
 {
 	struct dmub_rb flush_rb;
 
@@ -846,13 +855,13 @@ enum dmub_status dmub_srv_cmd_execute(struct dmub_srv *dmub)
 	 * been flushed to framebuffer memory. Otherwise DMCUB might
 	 * read back stale, fully invalid or partially invalid data.
 	 */
-	flush_rb = dmub->inbox1_rb;
+	flush_rb = dmub->inbox1.rb;
 	flush_rb.rptr = dmub->inbox1_last_wptr;
 	dmub_rb_flush_pending(&flush_rb);
 
-	dmub->hw_funcs.set_inbox1_wptr(dmub, dmub->inbox1_rb.wrpt);
+		dmub->hw_funcs.set_inbox1_wptr(dmub, dmub->inbox1.rb.wrpt);
 
-	dmub->inbox1_last_wptr = dmub->inbox1_rb.wrpt;
+	dmub->inbox1_last_wptr = dmub->inbox1.rb.wrpt;
 
 	return DMUB_STATUS_OK;
 }
@@ -910,26 +919,97 @@ enum dmub_status dmub_srv_wait_for_auto_load(struct dmub_srv *dmub,
 	return DMUB_STATUS_TIMEOUT;
 }
 
+static void dmub_srv_update_reg_inbox0_status(struct dmub_srv *dmub)
+{
+	if (dmub->reg_inbox0.is_pending) {
+		dmub->reg_inbox0.is_pending = dmub->hw_funcs.read_reg_inbox0_rsp_int_status &&
+				!dmub->hw_funcs.read_reg_inbox0_rsp_int_status(dmub);
+
+		if (!dmub->reg_inbox0.is_pending) {
+			/* ack the rsp interrupt */
+			if (dmub->hw_funcs.write_reg_inbox0_rsp_int_ack)
+				dmub->hw_funcs.write_reg_inbox0_rsp_int_ack(dmub);
+
+			/* only update the reported count if commands aren't being batched */
+			if (!dmub->reg_inbox0.is_pending && !dmub->reg_inbox0.is_multi_pending) {
+				dmub->reg_inbox0.num_reported = dmub->reg_inbox0.num_submitted;
+			}
+		}
+	}
+}
+
+enum dmub_status dmub_srv_wait_for_pending(struct dmub_srv *dmub,
+					uint32_t timeout_us)
+{
+	uint32_t i;
+	const uint32_t polling_interval_us = 1;
+	struct dmub_srv_inbox scratch_reg_inbox0 = dmub->reg_inbox0;
+	struct dmub_srv_inbox scratch_inbox1 = dmub->inbox1;
+	const volatile struct dmub_srv_inbox *reg_inbox0 = &dmub->reg_inbox0;
+	const volatile struct dmub_srv_inbox *inbox1 = &dmub->inbox1;
+
+	if (!dmub->hw_init ||
+			!dmub->hw_funcs.get_inbox1_wptr)
+		return DMUB_STATUS_INVALID;
+
+	/* take a snapshot of the required mailbox state */
+	scratch_inbox1.rb.wrpt = dmub->hw_funcs.get_inbox1_wptr(dmub);
+
+	for (i = 0; i <= timeout_us; i += polling_interval_us) {
+			scratch_inbox1.rb.rptr = dmub->hw_funcs.get_inbox1_rptr(dmub);
+
+		scratch_reg_inbox0.is_pending = scratch_reg_inbox0.is_pending &&
+				dmub->hw_funcs.read_reg_inbox0_rsp_int_status &&
+				!dmub->hw_funcs.read_reg_inbox0_rsp_int_status(dmub);
+
+		if (scratch_inbox1.rb.rptr > dmub->inbox1.rb.capacity)
+			return DMUB_STATUS_HW_FAILURE;
+
+		/* check current HW state first, but use command submission vs reported as a fallback */
+		if ((dmub_rb_empty(&scratch_inbox1.rb) ||
+				inbox1->num_reported >= scratch_inbox1.num_submitted) &&
+				(!scratch_reg_inbox0.is_pending ||
+				reg_inbox0->num_reported >= scratch_reg_inbox0.num_submitted))
+			return DMUB_STATUS_OK;
+
+		udelay(polling_interval_us);
+	}
+
+	return DMUB_STATUS_TIMEOUT;
+}
+
 enum dmub_status dmub_srv_wait_for_idle(struct dmub_srv *dmub,
 					uint32_t timeout_us)
 {
 	uint32_t i, rptr;
+	const uint32_t polling_interval_us = 1;
 
 	if (!dmub->hw_init)
 		return DMUB_STATUS_INVALID;
 
-	for (i = 0; i <= timeout_us; ++i) {
-		rptr = dmub->hw_funcs.get_inbox1_rptr(dmub);
+	for (i = 0; i < timeout_us; i += polling_interval_us) {
+		/* update inbox1 state */
+			rptr = dmub->hw_funcs.get_inbox1_rptr(dmub);
 
-		if (rptr > dmub->inbox1_rb.capacity)
+		if (rptr > dmub->inbox1.rb.capacity)
 			return DMUB_STATUS_HW_FAILURE;
 
-		dmub->inbox1_rb.rptr = rptr;
+		if (dmub->inbox1.rb.rptr > rptr) {
+			/* rb wrapped */
+			dmub->inbox1.num_reported += (rptr + dmub->inbox1.rb.capacity - dmub->inbox1.rb.rptr) / DMUB_RB_CMD_SIZE;
+		} else {
+			dmub->inbox1.num_reported += (rptr - dmub->inbox1.rb.rptr) / DMUB_RB_CMD_SIZE;
+		}
+		dmub->inbox1.rb.rptr = rptr;
+
+		/* update reg_inbox0 */
+		dmub_srv_update_reg_inbox0_status(dmub);
 
-		if (dmub_rb_empty(&dmub->inbox1_rb))
+		/* check for idle */
+		if (dmub_rb_empty(&dmub->inbox1.rb) && !dmub->reg_inbox0.is_pending)
 			return DMUB_STATUS_OK;
 
-		udelay(1);
+		udelay(polling_interval_us);
 	}
 
 	return DMUB_STATUS_TIMEOUT;
@@ -1040,35 +1120,6 @@ enum dmub_status dmub_srv_set_skip_panel_power_sequence(struct dmub_srv *dmub,
 	return DMUB_STATUS_OK;
 }
 
-enum dmub_status dmub_srv_cmd_with_reply_data(struct dmub_srv *dmub,
-					      union dmub_rb_cmd *cmd)
-{
-	enum dmub_status status = DMUB_STATUS_OK;
-
-	// Queue command
-	status = dmub_srv_cmd_queue(dmub, cmd);
-
-	if (status != DMUB_STATUS_OK)
-		return status;
-
-	// Execute command
-	status = dmub_srv_cmd_execute(dmub);
-
-	if (status != DMUB_STATUS_OK)
-		return status;
-
-	// Wait for DMUB to process command
-	status = dmub_srv_wait_for_idle(dmub, 100000);
-
-	if (status != DMUB_STATUS_OK)
-		return status;
-
-	// Copy data back from ring buffer into command
-	dmub_rb_get_return_data(&dmub->inbox1_rb, cmd);
-
-	return status;
-}
-
 static inline bool dmub_rb_out_trace_buffer_front(struct dmub_rb *rb,
 				 void *entry)
 {
@@ -1160,46 +1211,105 @@ void dmub_srv_subvp_save_surf_addr(struct dmub_srv *dmub, const struct dc_plane_
 	}
 }
 
-enum dmub_status dmub_srv_send_reg_inbox0_cmd(
-		struct dmub_srv *dmub,
-		union dmub_rb_cmd *cmd,
-		bool with_reply, uint32_t timeout_us)
+void dmub_srv_set_power_state(struct dmub_srv *dmub, enum dmub_srv_power_state_type dmub_srv_power_state)
 {
-	uint32_t rsp_ready = 0;
-	uint32_t i;
+	if (!dmub || !dmub->hw_init)
+		return;
+
+	dmub->power_state = dmub_srv_power_state;
+}
+
+enum dmub_status dmub_srv_reg_cmd_execute(struct dmub_srv *dmub, union dmub_rb_cmd *cmd)
+{
+	uint32_t num_pending = 0;
+
+	if (!dmub->hw_init)
+		return DMUB_STATUS_INVALID;
+
+	if (dmub->power_state != DMUB_POWER_STATE_D0)
+		return DMUB_STATUS_POWER_STATE_D3;
+
+	if (!dmub->hw_funcs.send_reg_inbox0_cmd_msg ||
+			!dmub->hw_funcs.clear_reg_inbox0_rsp_int_ack)
+		return DMUB_STATUS_INVALID;
+
+	if (dmub->reg_inbox0.num_submitted >= dmub->reg_inbox0.num_reported)
+		num_pending = dmub->reg_inbox0.num_submitted - dmub->reg_inbox0.num_reported;
+	else
+		/* num_submitted wrapped */
+		num_pending = DMUB_REG_INBOX0_RB_MAX_ENTRY -
+				(dmub->reg_inbox0.num_reported - dmub->reg_inbox0.num_submitted);
 
+	if (num_pending >= DMUB_REG_INBOX0_RB_MAX_ENTRY)
+		return DMUB_STATUS_QUEUE_FULL;
+
+	/* clear last rsp ack and send message */
+	dmub->hw_funcs.clear_reg_inbox0_rsp_int_ack(dmub);
 	dmub->hw_funcs.send_reg_inbox0_cmd_msg(dmub, cmd);
 
-	for (i = 0; i < timeout_us; i++) {
-		rsp_ready = dmub->hw_funcs.read_reg_inbox0_rsp_int_status(dmub);
-		if (rsp_ready)
-			break;
-		udelay(1);
+	dmub->reg_inbox0.num_submitted++;
+	dmub->reg_inbox0.is_pending = true;
+	dmub->reg_inbox0.is_multi_pending = cmd->cmd_common.header.multi_cmd_pending;
+
+	return DMUB_STATUS_OK;
+}
+
+void dmub_srv_cmd_get_response(struct dmub_srv *dmub,
+		union dmub_rb_cmd *cmd_rsp)
+{
+	if (dmub) {
+		if (dmub->inbox_type == DMUB_CMD_INTERFACE_REG &&
+				dmub->hw_funcs.read_reg_inbox0_cmd_rsp) {
+			dmub->hw_funcs.read_reg_inbox0_cmd_rsp(dmub, cmd_rsp);
+		} else {
+			dmub_rb_get_return_data(&dmub->inbox1.rb, cmd_rsp);
+		}
 	}
-	if (rsp_ready == 0)
-		return DMUB_STATUS_TIMEOUT;
+}
 
-	if (with_reply)
-		dmub->hw_funcs.read_reg_inbox0_cmd_rsp(dmub, cmd);
+static enum dmub_status dmub_srv_sync_reg_inbox0(struct dmub_srv *dmub)
+{
+	if (!dmub || !dmub->sw_init)
+		return DMUB_STATUS_INVALID;
 
-	dmub->hw_funcs.write_reg_inbox0_rsp_int_ack(dmub);
+	dmub->reg_inbox0.is_pending = 0;
+	dmub->reg_inbox0.is_multi_pending = 0;
 
-	/* wait for rsp int status is cleared to initial state before exit */
-	for (; i <= timeout_us; i++) {
-		rsp_ready = dmub->hw_funcs.read_reg_inbox0_rsp_int_status(dmub);
-		if (rsp_ready == 0)
-			break;
-		udelay(1);
+	return DMUB_STATUS_OK;
+}
+
+static enum dmub_status dmub_srv_sync_inbox1(struct dmub_srv *dmub)
+{
+	if (!dmub->sw_init)
+		return DMUB_STATUS_INVALID;
+
+	if (dmub->hw_funcs.get_inbox1_rptr && dmub->hw_funcs.get_inbox1_wptr) {
+		uint32_t rptr = dmub->hw_funcs.get_inbox1_rptr(dmub);
+		uint32_t wptr = dmub->hw_funcs.get_inbox1_wptr(dmub);
+
+		if (rptr > dmub->inbox1.rb.capacity || wptr > dmub->inbox1.rb.capacity) {
+			return DMUB_STATUS_HW_FAILURE;
+		} else {
+			dmub->inbox1.rb.rptr = rptr;
+			dmub->inbox1.rb.wrpt = wptr;
+			dmub->inbox1_last_wptr = dmub->inbox1.rb.wrpt;
+		}
 	}
-	ASSERT(rsp_ready == 0);
 
 	return DMUB_STATUS_OK;
 }
 
-void dmub_srv_set_power_state(struct dmub_srv *dmub, enum dmub_srv_power_state_type dmub_srv_power_state)
+enum dmub_status dmub_srv_sync_inboxes(struct dmub_srv *dmub)
 {
-	if (!dmub || !dmub->hw_init)
-		return;
+	enum dmub_status status;
 
-	dmub->power_state = dmub_srv_power_state;
+	status = dmub_srv_sync_reg_inbox0(dmub);
+	if (status != DMUB_STATUS_OK)
+		return status;
+
+	status = dmub_srv_sync_inbox1(dmub);
+	if (status != DMUB_STATUS_OK)
+		return status;
+
+	return DMUB_STATUS_OK;
 }