[PATCH v4 22/39] drm/msm/dp: Add support for sending VCPF packets in DP controller

[Yongxing Mou <yongxing.mou@oss.qualcomm.com>]

From: Abhinav Kumar <quic_abhinavk@quicinc.com>

The VC Payload Fill (VCPF) sequence is inserted by the DP controller
when stream symbols are absent, typically before a stream is disabled.
This patch adds support for triggering the VCPF sequence in the MSM DP
controller.

Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_ctrl.c    | 55 ++++++++++++++++++++++++++++++++++---
 drivers/gpu/drm/msm/dp/dp_ctrl.h    |  2 +-
 drivers/gpu/drm/msm/dp/dp_display.c |  2 +-
 drivers/gpu/drm/msm/dp/dp_reg.h     |  5 ++++
 4 files changed, 58 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index e64f81bc8c36..9907f2e56e65 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -65,9 +65,18 @@
 	(PSR_UPDATE_MASK | PSR_CAPTURE_MASK | PSR_EXIT_MASK | \
 	PSR_UPDATE_ERROR_MASK | PSR_WAKE_ERROR_MASK)
 
+#define DP_INTERRUPT_STATUS5 \
+	(DP_INTR_DP0_VCPF_SENT | DP_INTR_DP1_VCPF_SENT)
+#define DP_INTERRUPT_STATUS5_MASK \
+	(DP_INTERRUPT_STATUS5 << DP_INTERRUPT_STATUS_MASK_SHIFT)
+
 #define DP_CTRL_INTR_READY_FOR_VIDEO     BIT(0)
 #define DP_CTRL_INTR_IDLE_PATTERN_SENT  BIT(3)
 
+#define DP_DP0_PUSH_VCPF		BIT(12)
+#define DP_DP1_PUSH_VCPF		BIT(14)
+#define DP_MSTLINK_PUSH_VCPF		BIT(12)
+
 #define MR_LINK_TRAINING1  0x8
 #define MR_LINK_SYMBOL_ERM 0x80
 #define MR_LINK_PRBS7 0x100
@@ -405,6 +414,8 @@ void msm_dp_ctrl_enable_irq(struct msm_dp_ctrl *msm_dp_ctrl)
 			DP_INTERRUPT_STATUS1_MASK);
 	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS2,
 			DP_INTERRUPT_STATUS2_MASK);
+	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS5,
+			 DP_INTERRUPT_STATUS5_MASK);
 }
 
 void msm_dp_ctrl_disable_irq(struct msm_dp_ctrl *msm_dp_ctrl)
@@ -414,6 +425,7 @@ void msm_dp_ctrl_disable_irq(struct msm_dp_ctrl *msm_dp_ctrl)
 
 	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS, 0x00);
 	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS2, 0x00);
+	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS5, 0x00);
 }
 
 static u32 msm_dp_ctrl_get_psr_interrupt(struct msm_dp_ctrl_private *ctrl)
@@ -433,6 +445,20 @@ static void msm_dp_ctrl_config_psr_interrupt(struct msm_dp_ctrl_private *ctrl)
 	msm_dp_write_ahb(ctrl, REG_DP_INTR_MASK4, DP_INTERRUPT_MASK4);
 }
 
+static u32 msm_dp_ctrl_get_mst_interrupt(struct msm_dp_ctrl_private *ctrl)
+{
+	u32 intr, intr_ack;
+
+	intr = msm_dp_read_ahb(ctrl, REG_DP_INTR_STATUS5);
+	intr &= ~DP_INTERRUPT_STATUS5_MASK;
+	intr_ack = (intr & DP_INTERRUPT_STATUS5)
+			<< DP_INTERRUPT_STATUS_ACK_SHIFT;
+	msm_dp_write_ahb(ctrl, REG_DP_INTR_STATUS5,
+			 intr_ack | DP_INTERRUPT_STATUS5_MASK);
+
+	return intr;
+}
+
 static void msm_dp_ctrl_psr_mainlink_enable(struct msm_dp_ctrl_private *ctrl)
 {
 	u32 val;
@@ -516,14 +542,28 @@ static bool msm_dp_ctrl_mainlink_ready(struct msm_dp_ctrl_private *ctrl)
 	return true;
 }
 
-void msm_dp_ctrl_push_idle(struct msm_dp_ctrl *msm_dp_ctrl)
+void msm_dp_ctrl_push_idle(struct msm_dp_ctrl *msm_dp_ctrl, struct msm_dp_panel *msm_dp_panel)
 {
 	struct msm_dp_ctrl_private *ctrl;
+	u32 state = 0x0;
 
 	ctrl = container_of(msm_dp_ctrl, struct msm_dp_ctrl_private, msm_dp_ctrl);
 
+	if (!ctrl->mst_active)
+		state |= DP_STATE_CTRL_PUSH_IDLE;
+	else if (msm_dp_panel->stream_id == DP_STREAM_0)
+		state |= DP_DP0_PUSH_VCPF;
+	else if (msm_dp_panel->stream_id == DP_STREAM_1)
+		state |= DP_DP1_PUSH_VCPF;
+	else
+		state |= DP_MSTLINK_PUSH_VCPF;
+
 	reinit_completion(&ctrl->idle_comp);
-	msm_dp_write_link(ctrl, 0, REG_DP_STATE_CTRL, DP_STATE_CTRL_PUSH_IDLE);
+
+	msm_dp_write_link(ctrl, msm_dp_panel->stream_id,
+			  msm_dp_panel->stream_id > 1 ?
+			  REG_DP_MSTLINK_STATE_CTRL : REG_DP_STATE_CTRL,
+			  state);
 
 	if (!wait_for_completion_timeout(&ctrl->idle_comp,
 			IDLE_PATTERN_COMPLETION_TIMEOUT_JIFFIES))
@@ -2073,7 +2113,7 @@ void msm_dp_ctrl_set_psr(struct msm_dp_ctrl *msm_dp_ctrl, bool enter)
 			return;
 		}
 
-		msm_dp_ctrl_push_idle(msm_dp_ctrl);
+		msm_dp_ctrl_push_idle(msm_dp_ctrl, ctrl->panel);
 		msm_dp_write_link(ctrl, 0, REG_DP_STATE_CTRL, 0);
 
 		msm_dp_ctrl_psr_mainlink_disable(ctrl);
@@ -2183,7 +2223,7 @@ static int msm_dp_ctrl_link_maintenance(struct msm_dp_ctrl_private *ctrl)
 	int ret = 0;
 	int training_step = DP_TRAINING_NONE;
 
-	msm_dp_ctrl_push_idle(&ctrl->msm_dp_ctrl);
+	msm_dp_ctrl_push_idle(&ctrl->msm_dp_ctrl, ctrl->panel);
 
 	ctrl->link->phy_params.p_level = 0;
 	ctrl->link->phy_params.v_level = 0;
@@ -3005,6 +3045,13 @@ irqreturn_t msm_dp_ctrl_isr(struct msm_dp_ctrl *msm_dp_ctrl)
 		ret = IRQ_HANDLED;
 	}
 
+	isr = msm_dp_ctrl_get_mst_interrupt(ctrl);
+	if (isr & (DP_INTR_DP0_VCPF_SENT | DP_INTR_DP1_VCPF_SENT)) {
+		drm_dbg_dp(ctrl->drm_dev, "vcpf sent\n");
+		complete(&ctrl->idle_comp);
+		ret = IRQ_HANDLED;
+	}
+
 	/* DP aux isr */
 	isr = msm_dp_ctrl_get_aux_interrupt(ctrl);
 	if (isr)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp_ctrl.h
index c59338199399..cfe7e4496943 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
@@ -22,7 +22,7 @@ int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl,
 int msm_dp_ctrl_prepare_stream_on(struct msm_dp_ctrl *msm_dp_ctrl, bool force_link_train);
 void msm_dp_ctrl_off_link(struct msm_dp_ctrl *msm_dp_ctrl);
 void msm_dp_ctrl_off_pixel_clk(struct msm_dp_ctrl *msm_dp_ctrl, enum msm_dp_stream_id stream_id);
-void msm_dp_ctrl_push_idle(struct msm_dp_ctrl *msm_dp_ctrl);
+void msm_dp_ctrl_push_idle(struct msm_dp_ctrl *msm_dp_ctrl, struct msm_dp_panel *msm_dp_panel);
 irqreturn_t msm_dp_ctrl_isr(struct msm_dp_ctrl *msm_dp_ctrl);
 void msm_dp_ctrl_handle_sink_request(struct msm_dp_ctrl *msm_dp_ctrl);
 struct msm_dp_ctrl *msm_dp_ctrl_get(struct device *dev,
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index e0bf4dffa6af..e8028402f748 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1557,7 +1557,7 @@ void msm_dp_display_atomic_disable(struct msm_dp *msm_dp_display)
 
 	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
 
-	msm_dp_ctrl_push_idle(dp->ctrl);
+	msm_dp_ctrl_push_idle(dp->ctrl, dp->panel);
 	msm_dp_ctrl_mst_stream_channel_slot_setup(dp->ctrl);
 	msm_dp_ctrl_mst_send_act(dp->ctrl);
 }
diff --git a/drivers/gpu/drm/msm/dp/dp_reg.h b/drivers/gpu/drm/msm/dp/dp_reg.h
index 835a55446868..65695fcb48d0 100644
--- a/drivers/gpu/drm/msm/dp/dp_reg.h
+++ b/drivers/gpu/drm/msm/dp/dp_reg.h
@@ -42,9 +42,13 @@
 #define DP_INTR_FRAME_END		BIT(6)
 #define DP_INTR_CRC_UPDATED		BIT(9)
 
+#define DP_INTR_DP0_VCPF_SENT		BIT(0)
+#define DP_INTR_DP1_VCPF_SENT		BIT(3)
+
 #define REG_DP_INTR_STATUS3			(0x00000028)
 
 #define REG_DP_INTR_STATUS4			(0x0000002C)
+#define REG_DP_INTR_STATUS5			(0x00000034)
 #define PSR_UPDATE_INT				(0x00000001)
 #define PSR_CAPTURE_INT				(0x00000004)
 #define PSR_EXIT_INT				(0x00000010)
@@ -356,6 +360,7 @@
 #define REG_DP_DP0_RG				(0x000004F8)
 #define REG_DP_DP1_RG				(0x000004FC)
 
+#define REG_DP_MSTLINK_STATE_CTRL		(0x00000000)
 #define REG_DP_MSTLINK_CONFIGURATION_CTRL	(0x00000034)
 #define REG_DP_MSTLINK_TIMESLOT_1_32		(0x00000038)
 #define REG_DP_MSTLINK_TIMESLOT_33_63		(0x0000003C)

-- 
2.43.0