Commit 263add30 authored by Fangzhi Zuo's avatar Fangzhi Zuo Committed by sanglipeng
Browse files

drm/amd/display: Add DSC Support for Synaptics Cascaded MST Hub 

stable inclusion
from stable-v5.10.177
commit 7051d51f1241d02a9db159485bddfe508427ab01
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I88YNP

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=7051d51f1241d02a9db159485bddfe508427ab01



--------------------------------

commit f4f3b7de upstream.

Traditional synaptics hub has one MST branch device without virtual dpcd.
Synaptics cascaded hub has two chained MST branch devices. DSC decoding
is performed via root MST branch device, instead of the second MST branch
device.

Reviewed-by: default avatarHersen Wu <hersenxs.wu@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarFangzhi Zuo <Jerry.Zuo@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarsanglipeng <sanglipeng1@jd.com>
parent 5a49f8f4

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c

+19 −0
Original line number Diff line number Diff line
@@ -164,6 +164,21 @@ static bool needs_dsc_aux_workaround(struct dc_link *link) 
	return false;

}



bool is_synaptics_cascaded_panamera(struct dc_link *link, struct drm_dp_mst_port *port)

{

	u8 branch_vendor_data[4] = { 0 }; // Vendor data 0x50C ~ 0x50F



	if (drm_dp_dpcd_read(port->mgr->aux, DP_BRANCH_VENDOR_SPECIFIC_START, &branch_vendor_data, 4) == 4) {

		if (link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_90CC24 &&

				IS_SYNAPTICS_CASCADED_PANAMERA(link->dpcd_caps.branch_dev_name, branch_vendor_data)) {

			DRM_INFO("Synaptics Cascaded MST hub\n");

			return true;

		}

	}



	return false;

}



static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnector)

{

	struct dc_sink *dc_sink = aconnector->dc_sink;
@@ -185,6 +200,10 @@ static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnecto 
	    needs_dsc_aux_workaround(aconnector->dc_link))

		aconnector->dsc_aux = &aconnector->mst_port->dm_dp_aux.aux;



	/* synaptics cascaded MST hub case */

	if (!aconnector->dsc_aux && is_synaptics_cascaded_panamera(aconnector->dc_link, port))

		aconnector->dsc_aux = port->mgr->aux;



	if (!aconnector->dsc_aux)

		return false;

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h

+12 −0
Original line number Diff line number Diff line
@@ -26,6 +26,18 @@ 
#ifndef __DAL_AMDGPU_DM_MST_TYPES_H__

#define __DAL_AMDGPU_DM_MST_TYPES_H__



#define DP_BRANCH_VENDOR_SPECIFIC_START 0x50C



/**

 * Panamera MST Hub detection

 * Offset DPCD 050Eh == 0x5A indicates cascaded MST hub case

 * Check from beginning of branch device vendor specific field (050Ch)

 */

#define IS_SYNAPTICS_PANAMERA(branchDevName) (((int)branchDevName[4] & 0xF0) == 0x50 ? 1 : 0)

#define BRANCH_HW_REVISION_PANAMERA_A2 0x10

#define SYNAPTICS_CASCADED_HUB_ID  0x5A

#define IS_SYNAPTICS_CASCADED_PANAMERA(devName, data) ((IS_SYNAPTICS_PANAMERA(devName) && ((int)data[2] == SYNAPTICS_CASCADED_HUB_ID)) ? 1 : 0)



struct amdgpu_display_manager;

struct amdgpu_dm_connector;