openwrt/target/linux/mvebu/patches-5.4/552-arm64-dts-marvell-armada-37xx-Set-pcie_reset_pin-to-.patch
Pali Rohár eb777539fd mvebu: armada-37xx: Backport PCI aardvark patches
This commit contains patches for PCI aardvark driver and relevant DTS
changes for Turris MOX and EspressoBin backported from mainline kernel.
It fixes support for old ATF, various wifi cards, mainly Compex WLE900VX.

Signed-off-by: Pali Rohár <pali@kernel.org>
2020-10-11 16:16:24 +02:00

94 lines
3.4 KiB
Diff

From 715878016984b2617f6c1f177c50039e12e7bd5b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Beh=C3=BAn?= <marek.behun@nic.cz>
Date: Thu, 30 Apr 2020 10:06:23 +0200
Subject: [PATCH] arm64: dts: marvell: armada-37xx: Set pcie_reset_pin to gpio
function
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
We found out that we are unable to control the PERST# signal via the
default pin dedicated to be PERST# pin (GPIO2[3] pin) on A3700 SOC when
this pin is in EP_PCIE1_Resetn mode. There is a register in the PCIe
register space called PERSTN_GPIO_EN (D0088004[3]), but changing the
value of this register does not change the pin output when measuring
with voltmeter.
We do not know if this is a bug in the SOC, or if it works only when
PCIe controller is in a certain state.
Commit f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready
before training link") says that when this pin changes pinctrl mode
from EP_PCIE1_Resetn to GPIO, the PERST# signal is asserted for a brief
moment.
So currently the situation is that on A3700 boards the PERST# signal is
asserted in U-Boot (because the code in U-Boot issues reset via this pin
via GPIO mode), and then in Linux by the obscure and undocumented
mechanism described by the above mentioned commit.
We want to issue PERST# signal in a known way, therefore this patch
changes the pcie_reset_pin function from "pcie" to "gpio" and adds the
reset-gpios property to the PCIe node in device tree files of
EspressoBin and Armada 3720 Dev Board (Turris Mox device tree already
has this property and uDPU does not have a PCIe port).
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Remi Pommarel <repk@triplefau.lt>
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Acked-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
---
arch/arm64/boot/dts/marvell/armada-3720-db.dts | 3 +++
arch/arm64/boot/dts/marvell/armada-3720-espressobin.dtsi | 1 +
arch/arm64/boot/dts/marvell/armada-3720-turris-mox.dts | 4 ----
arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 2 +-
4 files changed, 5 insertions(+), 5 deletions(-)
--- a/arch/arm64/boot/dts/marvell/armada-3720-db.dts
+++ b/arch/arm64/boot/dts/marvell/armada-3720-db.dts
@@ -128,6 +128,9 @@
/* CON15(V2.0)/CON17(V1.4) : PCIe / CON15(V2.0)/CON12(V1.4) :mini-PCIe */
&pcie0 {
+ pinctrl-names = "default";
+ pinctrl-0 = <&pcie_reset_pins &pcie_clkreq_pins>;
+ reset-gpios = <&gpiosb 3 GPIO_ACTIVE_LOW>;
status = "okay";
};
--- a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
+++ b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts
@@ -55,6 +55,7 @@
phys = <&comphy1 0>;
pinctrl-names = "default";
pinctrl-0 = <&pcie_reset_pins &pcie_clkreq_pins>;
+ reset-gpios = <&gpiosb 3 GPIO_ACTIVE_LOW>;
};
/* J6 */
--- a/arch/arm64/boot/dts/marvell/armada-3720-turris-mox.dts
+++ b/arch/arm64/boot/dts/marvell/armada-3720-turris-mox.dts
@@ -120,10 +120,6 @@
};
};
-&pcie_reset_pins {
- function = "gpio";
-};
-
&pcie0 {
pinctrl-names = "default";
pinctrl-0 = <&pcie_reset_pins &pcie_clkreq_pins>;
--- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
@@ -318,7 +318,7 @@
pcie_reset_pins: pcie-reset-pins {
groups = "pcie1";
- function = "pcie";
+ function = "gpio";
};
pcie_clkreq_pins: pcie-clkreq-pins {