drm/amd/display: Display does not light up after S4 resume

[Why]
Dpia hpd interrupt processing is disabled when entering S4/S0i3 and
would be reenabled after detection completes during resuming. Because,
keeping hpd interrupts enabled during detection leads to multiple
detections for the same hpd transition. There is a S4 case where dpia
hpd interrupt is missed when driver is in transitioning from hpd
interrupt processing disable to enable and the display does not light
up.

[How]
- Added dmub inbox command DMUB_CMD__DPIA_HPD_INT_ENABLE to explicitly
control dmub to issue dpia hpd interrupt or not. If dpia hpd interrupt
is disabled, dmub will keep the hpd pending and post it once driver
reenables dpia hpd interrupt or when querying with
DMUB_CMD__QUERY_HPD_STATE.
- Added dmub boot option dpia_hpd_int_enable_supported to notify dmub
about whether DMUB_CMD__DPIA_HPD_INT_ENABLE command would be used.
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Mustapha Ghaddar <Mustapha.Ghaddar@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Meenakshikumar Somasundaram <meenakshikumar.somasundaram@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc.c

@@ -4656,6 +4656,37 @@ enum dc_status dc_process_dmub_set_mst_slots(const struct dc *dc,
 	return DC_OK;
 }
 
+/**
+ *****************************************************************************
+ *  Function: dc_process_dmub_dpia_hpd_int_enable
+ *
+ *  @brief
+ *		Submits dpia hpd int enable command to dmub via inbox message
+ *
+ *  @param
+ *		[in] dc: dc structure
+ *		[in] hpd_int_enable: 1 for hpd int enable, 0 to disable
+ *
+ *	@return
+ *		None
+ *****************************************************************************
+ */
+void dc_process_dmub_dpia_hpd_int_enable(const struct dc *dc,
+				uint32_t hpd_int_enable)
+{
+	union dmub_rb_cmd cmd = {0};
+	struct dc_dmub_srv *dmub_srv = dc->ctx->dmub_srv;
+
+	cmd.dpia_hpd_int_enable.header.type = DMUB_CMD__DPIA_HPD_INT_ENABLE;
+	cmd.dpia_hpd_int_enable.enable = hpd_int_enable;
+
+	dc_dmub_srv_cmd_queue(dmub_srv, &cmd);
+	dc_dmub_srv_cmd_execute(dmub_srv);
+	dc_dmub_srv_wait_idle(dmub_srv);
+
+	DC_LOG_DEBUG("%s: hpd_int_enable(%d)\n", __func__, hpd_int_enable);
+}
+
 /**
  * dc_disable_accelerated_mode - disable accelerated mode
  * @dc: dc structure

drivers/gpu/drm/amd/display/dc/dc.h

@@ -1612,6 +1612,9 @@ enum dc_status dc_process_dmub_set_mst_slots(const struct dc *dc,
 				uint8_t mst_alloc_slots,
 				uint8_t *mst_slots_in_use);
 
+void dc_process_dmub_dpia_hpd_int_enable(const struct dc *dc,
+				uint32_t hpd_int_enable);
+
 /*******************************************************************************
  * DSC Interfaces
  ******************************************************************************/

drivers/gpu/drm/amd/display/dmub/dmub_srv.h

@@ -248,6 +248,7 @@ struct dmub_srv_hw_params {
 	bool disable_dpia;
 	bool usb4_cm_version;
 	bool fw_in_system_memory;
+	bool dpia_hpd_int_enable_supported;
 };
 
 /**

drivers/gpu/drm/amd/display/dmub/inc/dmub_cmd.h

@@ -400,8 +400,9 @@ union dmub_fw_boot_options {
 		uint32_t diag_env: 1; /* 1 if diagnostic environment */
 		uint32_t gpint_scratch8: 1; /* 1 if GPINT is in scratch8*/
 		uint32_t usb4_cm_version: 1; /**< 1 CM support */
+		uint32_t dpia_hpd_int_enable_supported: 1; /* 1 if dpia hpd int enable supported */
 
-		uint32_t reserved : 17; /**< reserved */
+		uint32_t reserved : 16; /**< reserved */
 	} bits; /**< boot bits */
 	uint32_t all; /**< 32-bit access to bits */
 };
@@ -728,6 +729,12 @@ enum dmub_cmd_type {
 	/**
 	 * Command type used for all VBIOS interface commands.
 	 */
+
+	/**
+	 * Command type used to set DPIA HPD interrupt state
+	 */
+	DMUB_CMD__DPIA_HPD_INT_ENABLE = 86,
+
 	DMUB_CMD__VBIOS = 128,
 };
 
@@ -1255,6 +1262,14 @@ struct dmub_rb_cmd_set_mst_alloc_slots {
 	struct dmub_cmd_mst_alloc_slots_control_data mst_slots_control; /* mst slots control */
 };
 
+/**
+ * DMUB command structure for DPIA HPD int enable control.
+ */
+struct dmub_rb_cmd_dpia_hpd_int_enable {
+	struct dmub_cmd_header header; /* header */
+	uint32_t enable; /* dpia hpd interrupt enable */
+};
+
 /**
  * struct dmub_rb_cmd_dpphy_init - DPPHY init.
  */
@@ -3336,6 +3351,10 @@ union dmub_rb_cmd {
 	 * Definition of a DMUB_CMD__QUERY_HPD_STATE command.
 	 */
 	struct dmub_rb_cmd_query_hpd_state query_hpd;
+	/**
+	 * Definition of a DMUB_CMD__DPIA_HPD_INT_ENABLE command.
+	 */
+	struct dmub_rb_cmd_dpia_hpd_int_enable dpia_hpd_int_enable;
 };
 
 /**

drivers/gpu/drm/amd/display/dmub/src/dmub_dcn31.c

@@ -350,6 +350,7 @@ void dmub_dcn31_enable_dmub_boot_options(struct dmub_srv *dmub, const struct dmu
 	boot_options.bits.dpia_supported = params->dpia_supported;
 	boot_options.bits.enable_dpia = params->disable_dpia ? 0 : 1;
 	boot_options.bits.usb4_cm_version = params->usb4_cm_version;
+	boot_options.bits.dpia_hpd_int_enable_supported = params->dpia_hpd_int_enable_supported;
 	boot_options.bits.power_optimization = params->power_optimization;
 
 	boot_options.bits.sel_mux_phy_c_d_phy_f_g = (dmub->asic == DMUB_ASIC_DCN31B) ? 1 : 0;