From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F007AC433F5 for ; Wed, 24 Nov 2021 22:50:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350153AbhKXWxo (ORCPT ); Wed, 24 Nov 2021 17:53:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:47560 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352236AbhKXWxi (ORCPT ); Wed, 24 Nov 2021 17:53:38 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 78897610A2; Wed, 24 Nov 2021 22:50:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637794228; bh=OQuOOjisVc2/Qyjtzt0KgzE66kwUVwPgulZo08KmWUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G3tx1vJ/vIPysHodnqY4dAO9PsCRo70haUIaSSJyy83rPtOxEtJIvrvCkwsWZHdyb pYd9elOQjVaZeNOWnpWodvVs0KgU4zLH8iQUXuea+NoX5id1lntn/nACVg9n/17J/s z6qdspn20dgYYq9sQtFqRLQQ/x7UCG/YmS0eWe2o8CMXKfZWiM1uQFmpE5YetdHUwo 7ep+m08UAkSAMBi2TNsBabPnqIwDlQ8U9cB1Dx/4OWtkb30AihgWlw57cqTUQpQ6fT LuYxCETmeepr5K7zorRrQ6O4Kg2b21U3VaoIw8q6AxARV0FkAhxZ/FL5Jw3cw75mVx ArlMZd/7qyRuw== From: =?UTF-8?q?Marek=20Beh=C3=BAn?= To: Greg Kroah-Hartman , Sasha Levin Cc: pali@kernel.org, stable@vger.kernel.org, =?UTF-8?q?Marek=20Beh=C3=BAn?= , Remi Pommarel , Tomasz Maciej Nowak , Thomas Petazzoni , Gregory CLEMENT , =?UTF-8?q?Marek=20Beh=C3=BAn?= Subject: [PATCH 4.14 24/24] arm64: dts: marvell: armada-37xx: Set pcie_reset_pin to gpio function Date: Wed, 24 Nov 2021 23:49:33 +0100 Message-Id: <20211124224933.24275-25-kabel@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211124224933.24275-1-kabel@kernel.org> References: <20211124224933.24275-1-kabel@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marek Behún commit 715878016984b2617f6c1f177c50039e12e7bd5b upstream. 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 Cc: Remi Pommarel Tested-by: Tomasz Maciej Nowak Acked-by: Thomas Petazzoni Signed-off-by: Gregory CLEMENT Signed-off-by: Marek Behún --- arch/arm64/boot/dts/marvell/armada-3720-db.dts | 3 +++ arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts | 3 +++ arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 2 +- 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/marvell/armada-3720-db.dts b/arch/arm64/boot/dts/marvell/armada-3720-db.dts index 9df0f06ce607..0a0e9e19e879 100644 --- a/arch/arm64/boot/dts/marvell/armada-3720-db.dts +++ b/arch/arm64/boot/dts/marvell/armada-3720-db.dts @@ -155,6 +155,9 @@ /* 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"; }; diff --git a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts index 13c0ec053ada..89c7385390f4 100644 --- a/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts +++ b/arch/arm64/boot/dts/marvell/armada-3720-espressobin.dts @@ -82,6 +82,9 @@ /* J9 */ &pcie0 { + pinctrl-names = "default"; + pinctrl-0 = <&pcie_reset_pins &pcie_clkreq_pins>; + reset-gpios = <&gpiosb 3 GPIO_ACTIVE_LOW>; status = "okay"; }; diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi index a4c81a1c77b7..b369356e7419 100644 --- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi +++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi @@ -241,7 +241,7 @@ pcie_reset_pins: pcie-reset-pins { groups = "pcie1"; - function = "pcie"; + function = "gpio"; }; pcie_clkreq_pins: pcie-clkreq-pins { -- 2.32.0