Unlike other drivers, the DPU driver checks for exact UBWC version,
making it hard to add minor versions if necessary. Invert the order of
UBWC checks, letting the DPU driver handle new minors transparently.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c | 36 ++++++++++++++---------------
 1 file changed, 18 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c
index 6089a58074ac..b5e50fc1916f 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c
@@ -310,35 +310,35 @@ void dpu_hw_setup_format_impl(struct dpu_sw_pipe *pipe, const struct msm_format
 
 	if (fmt->fetch_mode != MDP_FETCH_LINEAR) {
 		u32 hbb = ctx->ubwc->highest_bank_bit - 13;
-		u32 ctrl_val;
+		u32 ctrl_val = 0;
 
 		if (MSM_FORMAT_IS_UBWC(fmt))
 			opmode |= MDSS_MDP_OP_BWC_EN;
 		src_format |= (fmt->fetch_mode & 3) << 30; /*FRAME_FORMAT */
 
-		if (ctx->ubwc->ubwc_enc_version == UBWC_1_0) {
+		if (ctx->ubwc->ubwc_enc_version > UBWC_6_0) {
+			DRM_WARN_ONCE("Unsupported UBWC version %x\n", ctx->ubwc->ubwc_enc_version);
+		} else if (ctx->ubwc->ubwc_enc_version >= UBWC_5_0) {
+			if (!MSM_FORMAT_IS_YUV(fmt)) {
+				ctrl_val = BIT(30);
+				if (!MSM_FORMAT_IS_DX(fmt)) /* and not FP16, but it's unsupported */
+					ctrl_val |= BIT(31);
+			}
+			/* SDE also sets bits for lossy formats, but we don't support them yet */
+		} else if (ctx->ubwc->ubwc_enc_version >= UBWC_4_0) {
+			ctrl_val = MSM_FORMAT_IS_YUV(fmt) ? 0 : BIT(30);
+		} else if (ctx->ubwc->ubwc_enc_version >= UBWC_3_0) {
+			ctrl_val = BIT(30) | qcom_ubwc_swizzle(ctx->ubwc) | (hbb << 4);
+		} else if (ctx->ubwc->ubwc_enc_version >= UBWC_2_0) {
+			fast_clear = fmt->alpha_enable ? BIT(31) : 0;
+			ctrl_val = fast_clear | qcom_ubwc_swizzle(ctx->ubwc) | (hbb << 4);
+		} else if (ctx->ubwc->ubwc_enc_version >= UBWC_1_0) {
 			fast_clear = fmt->alpha_enable ? BIT(31) : 0;
 			ctrl_val = fast_clear |
 				(qcom_ubwc_swizzle(ctx->ubwc) & UBWC_SWIZZLE_ENABLE_LVL1) |
 				BIT(8) | (hbb << 4);
-		} else if (ctx->ubwc->ubwc_enc_version == UBWC_2_0) {
-			fast_clear = fmt->alpha_enable ? BIT(31) : 0;
-			ctrl_val = fast_clear | qcom_ubwc_swizzle(ctx->ubwc) | (hbb << 4);
-		} else if (ctx->ubwc->ubwc_enc_version == UBWC_3_0) {
-			ctrl_val = BIT(30) | qcom_ubwc_swizzle(ctx->ubwc) | (hbb << 4);
-		} else if (ctx->ubwc->ubwc_enc_version == UBWC_4_0) {
-			ctrl_val = MSM_FORMAT_IS_YUV(fmt) ? 0 : BIT(30);
-		} else if (ctx->ubwc->ubwc_enc_version <= UBWC_6_0) {
-			if (MSM_FORMAT_IS_YUV(fmt))
-				ctrl_val = 0;
-			else if (MSM_FORMAT_IS_DX(fmt)) /* or FP16, but it's unsupported */
-				ctrl_val = BIT(30);
-			else
-				ctrl_val = BIT(30) | BIT(31);
-			/* SDE also sets bits for lossy formats, but we don't support them yet */
 		} else {
 			DRM_WARN_ONCE("Unsupported UBWC version %x\n", ctx->ubwc->ubwc_enc_version);
-			ctrl_val = 0;
 		}
 
 		DPU_REG_WRITE(c, ubwc_ctrl_off, ctrl_val);

-- 
2.47.3

On 3/12/26 2:29 PM, Dmitry Baryshkov wrote:
> Unlike other drivers, the DPU driver checks for exact UBWC version,
> making it hard to add minor versions if necessary. Invert the order of
> UBWC checks, letting the DPU driver handle new minors transparently.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> ---

[...]

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad

>  		} else {
>  			DRM_WARN_ONCE("Unsupported UBWC version %x\n", ctx->ubwc->ubwc_enc_version);

note this is existing behavior, but do we want to write to these
registers on platforms without UBWC, instead of returning early?

Konrad

On Fri, Mar 13, 2026 at 11:25:18AM +0100, Konrad Dybcio wrote:
> On 3/12/26 2:29 PM, Dmitry Baryshkov wrote:
> > Unlike other drivers, the DPU driver checks for exact UBWC version,
> > making it hard to add minor versions if necessary. Invert the order of
> > UBWC checks, letting the DPU driver handle new minors transparently.
> > 
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> > ---
> 
> [...]
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
> 
> Konrad
> 
> >  		} else {
> >  			DRM_WARN_ONCE("Unsupported UBWC version %x\n", ctx->ubwc->ubwc_enc_version);
> 
> note this is existing behavior, but do we want to write to these
> registers on platforms without UBWC, instead of returning early?

I'd really hope that developers who port DPU to such platforms will see
the warning and fix it during the porting effort.

-- 
With best wishes
Dmitry