Commit a06d565b authored by Mustapha Ghaddar's avatar Mustapha Ghaddar Committed by Alex Deucher
Browse files

drm/amd/display: Allocation at stream Enable 



[WHY & HOW]
After we allocate BW at plug, we will de-alloc
and allocate only what stream needs at
stream_enable()

[HOW]
Introduce bw allocation check at link_enable()
for DPIA links

Reviewed-by: default avatarWenjing Liu <Wenjing.Liu@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarMustapha Ghaddar <mghaddar@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 36951fc9

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

+2 −0
Original line number Diff line number Diff line
@@ -293,6 +293,8 @@ struct dc_link { 


	struct dc_panel_config panel_config;

	struct phy_state phy_state;

	// BW ALLOCATON USB4 ONLY

	struct dc_dpia_bw_alloc dpia_bw_alloc_config;

};

drivers/gpu/drm/amd/display/dc/link/link_dpms.c

+9 −2
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ 
#include "protocols/link_dp_capability.h"

#include "protocols/link_dp_training.h"

#include "protocols/link_edp_panel_control.h"

#include "protocols/link_dp_dpia_bw.h"



#include "dm_helpers.h"

#include "link_enc_cfg.h"
@@ -2044,11 +2045,17 @@ static enum dc_status enable_link_dp(struct dc_state *state, 
		}

	}



	/* Train with fallback when enabling DPIA link. Conventional links are

	/*

	 * If the link is DP-over-USB4 do the following:

	 * - Train with fallback when enabling DPIA link. Conventional links are

	 * trained with fallback during sink detection.

	 * - Allocate only what the stream needs for bw in Gbps. Inform the CM

	 * in case stream needs more or less bw from what has been allocated

	 * earlier at plug time.

	 */

	if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA)

	if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA) {

		do_fallback = true;

	}



	/*

	 * Temporary w/a to get DP2.0 link rates to work with SST.

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c

+32 −1
Original line number Diff line number Diff line
@@ -246,7 +246,7 @@ static bool get_cm_response_ready_flag(struct dc_link *link) 
// ------------------------------------------------------------------

//					PUBLIC FUNCTIONS

// ------------------------------------------------------------------

bool set_dptx_usb4_bw_alloc_support(struct dc_link *link)

bool link_dp_dpia_set_dptx_usb4_bw_alloc_support(struct dc_link *link)

{

	bool ret = false;

	uint8_t response = 0,
@@ -439,3 +439,34 @@ int dc_link_dp_dpia_handle_usb4_bandwidth_allocation_for_link(struct dc_link *li 
out:

	return ret;

}

int link_dp_dpia_allocate_usb4_bandwidth_for_stream(struct dc_link *link, int req_bw)

{

	int ret = 0;

	uint8_t timeout = 10;



	if (!get_bw_alloc_proceed_flag(link))

		goto out;



	/*

	 * Sometimes stream uses same timing parameters as the already

	 * allocated max sink bw so no need to re-alloc

	 */

	if (req_bw != link->dpia_bw_alloc_config.sink_allocated_bw) {

		dc_link_set_usb4_req_bw_req(link, req_bw);

		do {

			if (!timeout > 0)

				timeout--;

			else

				break;

			udelay(10 * 1000);

		} while (!get_cm_response_ready_flag(link));



		if (!timeout)

			ret = 0;// ERROR TIMEOUT waiting for response for allocating bw

		else if (link->dpia_bw_alloc_config.sink_allocated_bw > 0)

			ret = get_host_router_total_bw(link, HOST_ROUTER_BW_ALLOCATED);

	}



out:

	return ret;

}

drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.h

+13 −1
Original line number Diff line number Diff line
@@ -42,6 +42,18 @@ enum bw_type { 
 *

 * return: SUCCESS or FAILURE

 */

bool set_dptx_usb4_bw_alloc_support(struct dc_link *link);

bool link_dp_dpia_set_dptx_usb4_bw_alloc_support(struct dc_link *link);



/*

 * Allocates only what the stream needs for bw, so if:

 * If (stream_req_bw < or > already_allocated_bw_at_HPD)

 * => Deallocate Max Bw & then allocate only what the stream needs

 *

 * @link: pointer to the dc_link struct instance

 * @req_bw: Bw requested by the stream

 *

 * return: allocated bw else return 0

 */

int link_dp_dpia_allocate_usb4_bandwidth_for_stream(struct dc_link *link, int req_bw);



#endif /* DC_INC_LINK_DP_DPIA_BW_H_ */