drm/msm/dpu: Add missing safe_lut_tbl in sc8280xp catalog

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@quicinc.com
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

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 1ccd1edd693c54748a6c474fedbe064e8e33907a..4c0528794e7a7ef7eb05f69ebce8a94db64ce863 100644 (file)
--- 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
@@ -406,6 +406,7 @@ 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