Commit 5419a207 authored by Nicholas Kazlauskas's avatar Nicholas Kazlauskas Committed by Alex Deucher
Browse files

drm/amd/display: Notify idle link detection through shared state 



[Why]
We can hang in IPS2 checking DMCUB_SCRATCH0 for link detection state.

[How]
Replace the HW access with a check on the shared state bit. This will
work the same way as the SCRATCH0 but won't require a wake in the case
where link detection isn't required.

Reviewed-by: default avatarDuncan Ma <duncan.ma@amd.com>
Acked-by: default avatarWayne Lin <wayne.lin@amd.com>
Signed-off-by: default avatarNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent d2c5cb0c

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

+30 −0
Original line number Diff line number Diff line
@@ -1460,6 +1460,36 @@ void dc_dmub_srv_set_power_state(struct dc_dmub_srv *dc_dmub_srv, enum dc_acpi_c 
		dmub_srv_set_power_state(dmub, DMUB_POWER_STATE_D3);

}



bool dc_dmub_srv_should_detect(struct dc_dmub_srv *dc_dmub_srv)

{

	volatile const struct dmub_shared_state_ips_fw *ips_fw;

	bool reallow_idle = false, should_detect = false;



	if (!dc_dmub_srv || !dc_dmub_srv->dmub)

		return false;



	if (dc_dmub_srv->dmub->shared_state &&

	    dc_dmub_srv->dmub->meta_info.feature_bits.bits.shared_state_link_detection) {

		ips_fw = &dc_dmub_srv->dmub->shared_state[DMUB_SHARED_SHARE_FEATURE__IPS_FW].data.ips_fw;

		return ips_fw->signals.bits.detection_required;

	}



	/* Detection may require reading scratch 0 - exit out of idle prior to the read. */

	if (dc_dmub_srv->idle_allowed) {

		dc_dmub_srv_apply_idle_power_optimizations(dc_dmub_srv->ctx->dc, false);

		reallow_idle = true;

	}



	should_detect = dmub_srv_should_detect(dc_dmub_srv->dmub);



	/* Re-enter idle if we're not about to immediately redetect links. */

	if (!should_detect && reallow_idle && dc_dmub_srv->idle_exit_counter == 0 &&

	    !dc_dmub_srv->ctx->dc->debug.disable_dmub_reallow_idle)

		dc_dmub_srv_apply_idle_power_optimizations(dc_dmub_srv->ctx->dc, true);



	return should_detect;

}



void dc_dmub_srv_apply_idle_power_optimizations(const struct dc *dc, bool allow_idle)

{

	struct dc_dmub_srv *dc_dmub_srv = dc->ctx->dmub_srv;

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

+10 −0
Original line number Diff line number Diff line
@@ -111,6 +111,16 @@ void dc_dmub_srv_apply_idle_power_optimizations(const struct dc *dc, bool allow_ 


void dc_dmub_srv_set_power_state(struct dc_dmub_srv *dc_dmub_srv, enum dc_acpi_cm_power_state powerState);



/**

 * @dc_dmub_srv_should_detect() - Checks if link detection is required.

 *

 * While in idle power states we may need driver to manually redetect in

 * the case of a missing hotplug. Should be called from a polling timer.

 *

 * Return: true if redetection is required.

 */

bool dc_dmub_srv_should_detect(struct dc_dmub_srv *dc_dmub_srv);



/**

 * dc_wake_and_execute_dmub_cmd() - Wrapper for DMUB command execution.

 *

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

+1 −0
Original line number Diff line number Diff line
@@ -529,6 +529,7 @@ struct dmub_srv { 
	uint32_t psp_version;



	/* Feature capabilities reported by fw */

	struct dmub_fw_meta_info meta_info;

	struct dmub_feature_caps feature_caps;

	struct dmub_visual_confirm_color visual_confirm_color;

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

+14 −1
Original line number Diff line number Diff line
@@ -496,6 +496,17 @@ struct dmub_visual_confirm_color { 
/* Offset from the end of the file to the dmub_fw_meta_info */

#define DMUB_FW_META_OFFSET 0x24



/**

 * union dmub_fw_meta_feature_bits - Static feature bits for pre-initialization

 */

union dmub_fw_meta_feature_bits {

	struct {

		uint32_t shared_state_link_detection : 1; /**< 1 supports link detection via shared state */

		uint32_t reserved : 31;

	} bits; /**< status bits */

	uint32_t all; /**< 32-bit access to status bits */

};



/**

 * struct dmub_fw_meta_info - metadata associated with fw binary

 *
@@ -521,6 +532,7 @@ struct dmub_fw_meta_info { 
	uint32_t shared_state_size; /**< size of the shared state region in bytes */

	uint16_t shared_state_features; /**< number of shared state features */

	uint16_t reserved2; /**< padding bytes */

	union dmub_fw_meta_feature_bits feature_bits; /**< static feature bits */

};



/**
@@ -698,7 +710,8 @@ union dmub_shared_state_ips_fw_signals { 
		uint32_t ips1_commit : 1;  /**< 1 if in IPS1 */

		uint32_t ips2_commit : 1; /**< 1 if in IPS2 */

		uint32_t in_idle : 1; /**< 1 if DMCUB is in idle */

		uint32_t reserved_bits : 29; /**< Reversed */

		uint32_t detection_required : 1; /**< 1 if detection is required */

		uint32_t reserved_bits : 28; /**< Reversed */

	} bits;

	uint32_t all;

};

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

+2 −0
Original line number Diff line number Diff line
@@ -510,6 +510,8 @@ enum dmub_status 
	fw_info = dmub_get_fw_meta_info(params);



	if (fw_info) {

		memcpy(&dmub->meta_info, fw_info, sizeof(*fw_info));



		fw_state_size = fw_info->fw_region_size;

		trace_buffer_size = fw_info->trace_buffer_size;