linux-kernel - [PATCH v5 09/14] drm/msm/a6xx: Resolve the meaning of rgb565

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250625-topic-ubwc_central-v5-9-e256d18219e2@oss.qualcomm.com>
Date: Wed, 25 Jun 2025 15:10:17 +0200
From: Konrad Dybcio <konradybcio@...nel.org>
To: Bjorn Andersson <andersson@...nel.org>, 
 Konrad Dybcio <konradybcio@...nel.org>, 
 Abhinav Kumar <quic_abhinavk@...cinc.com>, 
 Dmitry Baryshkov <lumag@...nel.org>, Sean Paul <sean@...rly.run>, 
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
 Rob Clark <robin.clark@....qualcomm.com>, 
 Abhinav Kumar <abhinav.kumar@...ux.dev>, 
 Jessica Zhang <jessica.zhang@....qualcomm.com>, 
 Rob Clark <robin.clark@....qualcomm.com>, 
 Akhil P Oommen <akhilpo@....qualcomm.com>
Cc: Marijn Suijten <marijn.suijten@...ainline.org>, 
 linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org, 
 dri-devel@...ts.freedesktop.org, freedreno@...ts.freedesktop.org, 
 Konrad Dybcio <konrad.dybcio@....qualcomm.com>, 
 Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
Subject: [PATCH v5 09/14] drm/msm/a6xx: Resolve the meaning of
 rgb565_predicator

From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>

It's supposed to be on when the UBWC encoder version is >= 4.0.
Drop the per-GPU assignments.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
Signed-off-by: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 78782f94ee678e13baa6eb1a009a412e13557d59..53493f68ead2113143dab594bfedf492014d5aaa 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -610,7 +610,6 @@ static int a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
 	if (IS_ERR(gpu->common_ubwc_cfg))
 		return PTR_ERR(gpu->common_ubwc_cfg);
 
-	gpu->ubwc_config.rgb565_predicator = 0;
 	gpu->ubwc_config.min_acc_len = 0;
 	gpu->ubwc_config.ubwc_swizzle = 0x6;
 	gpu->ubwc_config.macrotile_mode = 0;
@@ -637,7 +636,6 @@ static int a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
 
 	if (adreno_is_a623(gpu)) {
 		gpu->ubwc_config.highest_bank_bit = 16;
-		gpu->ubwc_config.rgb565_predicator = 1;
 		gpu->ubwc_config.macrotile_mode = 1;
 	}
 
@@ -651,13 +649,11 @@ static int a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
 	    adreno_is_a740_family(gpu)) {
 		/* TODO: get ddr type from bootloader and use 2 for LPDDR4 */
 		gpu->ubwc_config.highest_bank_bit = 16;
-		gpu->ubwc_config.rgb565_predicator = 1;
 		gpu->ubwc_config.macrotile_mode = 1;
 	}
 
 	if (adreno_is_a663(gpu)) {
 		gpu->ubwc_config.highest_bank_bit = 13;
-		gpu->ubwc_config.rgb565_predicator = 1;
 		gpu->ubwc_config.macrotile_mode = 1;
 		gpu->ubwc_config.ubwc_swizzle = 0x4;
 	}
@@ -686,6 +682,7 @@ static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
 	 */
 	BUG_ON(adreno_gpu->ubwc_config.highest_bank_bit < 13);
 	u32 hbb = adreno_gpu->ubwc_config.highest_bank_bit - 13;
+	bool rgb565_predicator = cfg->ubwc_enc_version >= UBWC_4_0;
 	u32 level2_swizzling_dis = !(cfg->ubwc_swizzle & BIT(1));
 	bool ubwc_mode = qcom_ubwc_get_ubwc_mode(cfg);
 	bool amsbc = cfg->ubwc_enc_version >= UBWC_3_0;
@@ -698,7 +695,7 @@ static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
 
 	gpu_write(gpu, REG_A6XX_RB_NC_MODE_CNTL,
 		  level2_swizzling_dis << 12 |
-		  adreno_gpu->ubwc_config.rgb565_predicator << 11 |
+		  rgb565_predicator << 11 |
 		  hbb_hi << 10 | amsbc << 4 |
 		  adreno_gpu->ubwc_config.min_acc_len << 3 |
 		  hbb_lo << 1 | ubwc_mode);

-- 
2.50.0