[PATCH v3 2/2] arm64: tegra: fix aspm-l1-entry-delay-ns L1 latency cells
From: Manikanta Maddireddy
Date: Fri May 15 2026 - 03:10:08 EST
The Tegra194 PCIe driver converts aspm-l1-entry-delay-ns to whole ms
with ceiling division, then derives the Synopsys DesignWare PORT_AFR L1
entrance latency encoding as min(order_base_2(us), 7).
The nanosecond values from the Fixes tag below round up to 4, 8, and 16 us,
selecting PORT_AFR L1 entrance latency codes 2, 3, and 4 respectively.
Raise the programmed latency so the PORT_AFR codes are 3 / 4 / 5
(8 / 16 / 32 us buckets) instead of 2 / 3 / 4 (4 / 8 / 16 us).
- tegra194.dtsi: 4000 -> 8000 ns (all listed controllers)
- tegra234.dtsi: 8000 -> 16000 ns (Root Port), 16000 -> 32000 ns (Endpoint)
Fixes: d60ed99f1c9e ("arm64: tegra: Add aspm-l1-entry-delay-ns to PCIe nodes")
Signed-off-by: Manikanta Maddireddy <mmaddireddy@xxxxxxxxxx>
---
arch/arm64/boot/dts/nvidia/tegra194.dtsi | 18 ++++++-------
arch/arm64/boot/dts/nvidia/tegra234.dtsi | 32 ++++++++++++------------
2 files changed, 25 insertions(+), 25 deletions(-)
diff --git a/arch/arm64/boot/dts/nvidia/tegra194.dtsi b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
index 1d659454a6f9..7bbf0e892724 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
@@ -2382,7 +2382,7 @@ pcie@14100000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2435,7 +2435,7 @@ pcie@14120000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2488,7 +2488,7 @@ pcie@14140000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2541,7 +2541,7 @@ pcie@14160000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2587,7 +2587,7 @@ pcie-ep@14160000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
interconnects = <&mc TEGRA194_MEMORY_CLIENT_PCIE4R &emc>,
<&mc TEGRA194_MEMORY_CLIENT_PCIE4W &emc>;
@@ -2634,7 +2634,7 @@ pcie@14180000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2680,7 +2680,7 @@ pcie-ep@14180000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
interconnects = <&mc TEGRA194_MEMORY_CLIENT_PCIE0R &emc>,
<&mc TEGRA194_MEMORY_CLIENT_PCIE0W &emc>;
@@ -2730,7 +2730,7 @@ pcie@141a0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
bus-range = <0x0 0xff>;
@@ -2779,7 +2779,7 @@ pcie-ep@141a0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <4000>;
+ aspm-l1-entry-delay-ns = <8000>;
interconnects = <&mc TEGRA194_MEMORY_CLIENT_PCIE5R &emc>,
<&mc TEGRA194_MEMORY_CLIENT_PCIE5W &emc>;
diff --git a/arch/arm64/boot/dts/nvidia/tegra234.dtsi b/arch/arm64/boot/dts/nvidia/tegra234.dtsi
index 75bb9a0ad027..8e0c51e496e2 100644
--- a/arch/arm64/boot/dts/nvidia/tegra234.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra234.dtsi
@@ -4532,7 +4532,7 @@ pcie@140a0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4587,7 +4587,7 @@ pcie@140c0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4642,7 +4642,7 @@ pcie@140e0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4689,7 +4689,7 @@ pcie-ep@140e0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <16000>;
+ aspm-l1-entry-delay-ns = <32000>;
interconnects = <&mc TEGRA234_MEMORY_CLIENT_PCIE10AR &emc>,
<&mc TEGRA234_MEMORY_CLIENT_PCIE10AW &emc>;
@@ -4738,7 +4738,7 @@ pcie@14100000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4793,7 +4793,7 @@ pcie@14120000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4848,7 +4848,7 @@ pcie@14140000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4903,7 +4903,7 @@ pcie@14160000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -4945,7 +4945,7 @@ pcie-ep@14160000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <16000>;
+ aspm-l1-entry-delay-ns = <32000>;
interconnects = <&mc TEGRA234_MEMORY_CLIENT_PCIE4R &emc>,
<&mc TEGRA234_MEMORY_CLIENT_PCIE4W &emc>;
@@ -4992,7 +4992,7 @@ pcie@14180000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -5047,7 +5047,7 @@ pcie@141a0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -5094,7 +5094,7 @@ pcie-ep@141a0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <16000>;
+ aspm-l1-entry-delay-ns = <32000>;
interconnects = <&mc TEGRA234_MEMORY_CLIENT_PCIE5R &emc>,
<&mc TEGRA234_MEMORY_CLIENT_PCIE5W &emc>;
@@ -5143,7 +5143,7 @@ pcie@141c0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -5190,7 +5190,7 @@ pcie-ep@141c0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <16000>;
+ aspm-l1-entry-delay-ns = <32000>;
interconnects = <&mc TEGRA234_MEMORY_CLIENT_PCIE6AR &emc>,
<&mc TEGRA234_MEMORY_CLIENT_PCIE6AW &emc>;
@@ -5239,7 +5239,7 @@ pcie@141e0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <8000>;
+ aspm-l1-entry-delay-ns = <16000>;
bus-range = <0x0 0xff>;
@@ -5286,7 +5286,7 @@ pcie-ep@141e0000 {
nvidia,aspm-cmrt-us = <60>;
nvidia,aspm-pwr-on-t-us = <20>;
nvidia,aspm-l0s-entrance-latency-us = <3>;
- aspm-l1-entry-delay-ns = <16000>;
+ aspm-l1-entry-delay-ns = <32000>;
interconnects = <&mc TEGRA234_MEMORY_CLIENT_PCIE7AR &emc>,
<&mc TEGRA234_MEMORY_CLIENT_PCIE7AW &emc>;
--
2.34.1