From: Bjorn Andersson <quic_bjorande@quicinc.com> stable inclusion from stable-v6.6.4 commit 405b4f6d211345b1be64df938ef980e816519af3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8N1WC Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit a33b2431d11b4df137bbcfdd5a5adfa054c2479e upstream. During USB transfers on the SC8280XP __arm_smmu_tlb_sync() is seen to typically take 1-2ms to complete. As expected this results in poor performance, something that has been mitigated by proposing running the iommu in non-strict mode (boot with iommu.strict=0). This turns out to be related to the SAFE logic, and programming the QOS SAFE values in the DPU (per suggestion from Rob and Doug) reduces the TLB sync time to below 10us, which means significant less time spent with interrupts disabled and a significant boost in throughput. Fixes: 4a352c2fc15a ("drm/msm/dpu: Introduce SC8280XP") Cc: stable@vger.kernel.org Suggested-by: Doug Anderson <dianders@chromium.org> Suggested-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com> Tested-by: Johan Hovold <johan+linaro@kernel.org> Tested-by: Steev Klimaszewski <steev@kali.org> Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com> Patchwork: https://patchwork.freedesktop.org/patch/565094/ Link: https://lore.kernel.org/r/20231030-sc8280xp-dpu-safe-lut-v1-1-6d485d7b428f@q... Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_8_0_sc8280xp.h | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_8_0_sc8280xp.h b/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_8_0_sc8280xp.h index 58f5e25679b1..ff9adb8000ac 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_8_0_sc8280xp.h +++ b/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_8_0_sc8280xp.h @@ -419,6 +419,7 @@ static const struct dpu_perf_cfg sc8280xp_perf_data = { .min_llcc_ib = 0, .min_dram_ib = 800000, .danger_lut_tbl = {0xf, 0xffff, 0x0}, + .safe_lut_tbl = {0xfe00, 0xfe00, 0xffff}, .qos_lut_tbl = { {.nentry = ARRAY_SIZE(sc8180x_qos_linear), .entries = sc8180x_qos_linear -- 2.20.1