Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Bhupesh Sharma <bhupesh.sharma@linaro.org>
To:     linux-arm-msm@vger.kernel.org
Cc:     bhupesh.sharma@linaro.org, bhupesh.linux@gmail.com,
        linux-kernel@vger.kernel.org, bjorn.andersson@linaro.org,
        Vinod Koul <vkoul@kernel.org>
Subject: [PATCH 1/1] arm64: dts: qcom: sa8155p-adp: Disable multiple Tx and Rx queues for ethernet IP
Date:   Sun, 24 Apr 2022 01:20:03 +0530
Message-Id: <20220423195003.353150-1-bhupesh.sharma@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Fix the issues seen with ethernet traffic getting stalled on SA8155p-ADP
board with default (or larger) mtu size of 1500 bytes, by disabling
multiple Tx and Rx queues for the stmmac IP block.

With the single queue setup, the ethernet traffic is stable,
wget / curl can work well on the board and no ethernet stall is
observed even when longer netperf / iperf3 test are run. Also
a performance of ~940 Mbits/sec is observed on the 1G link, so
there is no observable degradation in performance as well.

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
---
 arch/arm64/boot/dts/qcom/sa8155p-adp.dts | 40 ++----------------------
 1 file changed, 2 insertions(+), 38 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sa8155p-adp.dts b/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
index 8034d0d31bd0..ba547ca9fc6b 100644
--- a/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
+++ b/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
@@ -49,7 +49,7 @@ vreg_s4a_1p8: smps4 {
 	};
 
 	mtl_rx_setup: rx-queues-config {
-		snps,rx-queues-to-use = <4>;
+		snps,rx-queues-to-use = <1>;
 		snps,rx-sched-sp;
 
 		queue0 {
@@ -58,28 +58,10 @@ queue0 {
 			snps,route-up;
 			snps,priority = <0x1>;
 		};
-
-		queue1 {
-			snps,dcb-algorithm;
-			snps,map-to-dma-channel = <0x1>;
-			snps,route-ptp;
-		};
-
-		queue2 {
-			snps,avb-algorithm;
-			snps,map-to-dma-channel = <0x2>;
-			snps,route-avcp;
-		};
-
-		queue3 {
-			snps,avb-algorithm;
-			snps,map-to-dma-channel = <0x3>;
-			snps,priority = <0xC>;
-		};
 	};
 
 	mtl_tx_setup: tx-queues-config {
-		snps,tx-queues-to-use = <4>;
+		snps,tx-queues-to-use = <1>;
 		snps,tx-sched-wrr;
 
 		queue0 {
@@ -87,24 +69,6 @@ queue0 {
 			snps,dcb-algorithm;
 			snps,priority = <0x0>;
 		};
-
-		queue1 {
-			snps,weight = <0x11>;
-			snps,dcb-algorithm;
-			snps,priority = <0x1>;
-		};
-
-		queue2 {
-			snps,weight = <0x12>;
-			snps,dcb-algorithm;
-			snps,priority = <0x2>;
-		};
-
-		queue3 {
-			snps,weight = <0x13>;
-			snps,dcb-algorithm;
-			snps,priority = <0x3>;
-		};
 	};
 };
 
-- 
2.35.1