drm/msm/a6xx: Fix the gemnoc workaround

Correct the register offset and enable this workaround for all A7x
and newer GPUs to match the recommendation. Also, downstream does this
w/a after moving the fence to allow mode. So do the same.

Fixes: dbfbb37 ("drm/msm/a6xx: Add A621 support")
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/688997/
Message-ID: <20251118-kaana-gpu-support-v4-3-86eeb8e93fb6@oss.qualcomm.com>
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>

Author: akhilpo-qcom

drivers/gpu/drm/msm/adreno/a6xx_gmu.c

@@ -511,8 +511,9 @@ static void a6xx_gemnoc_workaround(struct a6xx_gmu *gmu)
 	 * in the power down sequence not being fully executed. That in turn can
 	 * prevent CX_GDSC from collapsing. Assert Qactive to avoid this.
 	 */
-	if (adreno_is_a621(adreno_gpu) || adreno_is_7c3(adreno_gpu))
-		gmu_write(gmu, REG_A6XX_GMU_AO_AHB_FENCE_CTRL, BIT(0));
+	if (adreno_is_a7xx(adreno_gpu) || (adreno_is_a621(adreno_gpu) ||
+				adreno_is_7c3(adreno_gpu)))
+		gmu_write(gmu, REG_A6XX_GPU_GMU_CX_GMU_CX_FALNEXT_INTF, BIT(0));
 }
 
 /* Let the GMU know that we are about to go into slumber */
@@ -548,10 +549,9 @@ static int a6xx_gmu_notify_slumber(struct a6xx_gmu *gmu)
 	}
 
 out:
-	a6xx_gemnoc_workaround(gmu);
-
 	/* Put fence into allow mode */
 	gmu_write(gmu, REG_A6XX_GMU_AO_AHB_FENCE_CTRL, 0);
+	a6xx_gemnoc_workaround(gmu);
 	return ret;
 }