From: George Shen <george.shen@amd.com>
Date: Sat, 15 Feb 2025 03:00:13 +0000 (-0500)
Subject: drm/amd/display: Skip checking FRL_MODE bit for PCON BW determination
X-Git-Tag: v6.15-rc1~120^2~12^2~71
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0584bbcf0c53c133081100e4f4c9fe41e598d045;p=thirdparty%2Fkernel%2Flinux.git

drm/amd/display: Skip checking FRL_MODE bit for PCON BW determination

[Why/How]
Certain PCON will clear the FRL_MODE bit despite supporting the link BW
indicated in the other bits.

Thus, skip checking the FRL_MODE bit when interpreting the
hdmi_encoded_link_bw struct.

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
index da19f6a3b42bf..a774101226360 100644
--- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
+++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c
@@ -250,21 +250,21 @@ static uint32_t intersect_frl_link_bw_support(
 {
 	uint32_t supported_bw_in_kbps = max_supported_frl_bw_in_kbps;
 
-	// HDMI_ENCODED_LINK_BW bits are only valid if HDMI Link Configuration bit is 1 (FRL mode)
-	if (hdmi_encoded_link_bw.bits.FRL_MODE) {
-		if (hdmi_encoded_link_bw.bits.BW_48Gbps)
-			supported_bw_in_kbps = 48000000;
-		else if (hdmi_encoded_link_bw.bits.BW_40Gbps)
-			supported_bw_in_kbps = 40000000;
-		else if (hdmi_encoded_link_bw.bits.BW_32Gbps)
-			supported_bw_in_kbps = 32000000;
-		else if (hdmi_encoded_link_bw.bits.BW_24Gbps)
-			supported_bw_in_kbps = 24000000;
-		else if (hdmi_encoded_link_bw.bits.BW_18Gbps)
-			supported_bw_in_kbps = 18000000;
-		else if (hdmi_encoded_link_bw.bits.BW_9Gbps)
-			supported_bw_in_kbps = 9000000;
-	}
+	/* Skip checking FRL_MODE bit, as certain PCON will clear
+	 * it despite supporting the link BW indicated in the other bits.
+	 */
+	if (hdmi_encoded_link_bw.bits.BW_48Gbps)
+		supported_bw_in_kbps = 48000000;
+	else if (hdmi_encoded_link_bw.bits.BW_40Gbps)
+		supported_bw_in_kbps = 40000000;
+	else if (hdmi_encoded_link_bw.bits.BW_32Gbps)
+		supported_bw_in_kbps = 32000000;
+	else if (hdmi_encoded_link_bw.bits.BW_24Gbps)
+		supported_bw_in_kbps = 24000000;
+	else if (hdmi_encoded_link_bw.bits.BW_18Gbps)
+		supported_bw_in_kbps = 18000000;
+	else if (hdmi_encoded_link_bw.bits.BW_9Gbps)
+		supported_bw_in_kbps = 9000000;
 
 	return supported_bw_in_kbps;
 }