From patchwork Thu Jan 24 21:42:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 10780169 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B5985746 for ; Thu, 24 Jan 2019 21:44:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A39D32BC02 for ; Thu, 24 Jan 2019 21:44:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 928092F201; Thu, 24 Jan 2019 21:44:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 82C322BC02 for ; Thu, 24 Jan 2019 21:44:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726269AbfAXVoC (ORCPT ); Thu, 24 Jan 2019 16:44:02 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:53484 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbfAXVoC (ORCPT ); Thu, 24 Jan 2019 16:44:02 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id 6438744087E; Thu, 24 Jan 2019 23:43:59 +0200 (IST) From: Baruch Siach To: Thomas Petazzoni , Lorenzo Pieralisi , Bjorn Helgaas Cc: Andrew Lunn , Baruch Siach , Sven Auhagen , Jason Cooper , linux-pci@vger.kernel.org, Gregory Clement , Russell King , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth Subject: [PATCH v2] Revert "PCI: armada8k: Add support for gpio controlled reset signal" Date: Thu, 24 Jan 2019 23:42:45 +0200 Message-Id: X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This reverts commit 3d71746c420c1c1c27cf5c4e48f8fa0a6cfdc185. That commit breaks boot on Macchiatobin when a Mellanox NIC is in the PCIe slot. It turns out that full reset cycle requires first comphy serdes initialization. Reset signal toggle without comphy initialization makes access to PCI configuration registers stall indefinitely. U-Boot toggles the Macchiatobin PCIe reset line already at boot, after initializing the comphy serdes. So while commit 3d71746c42 ("PCI: armada8k: Add support for gpio controlled reset signal") enables PCIe on platforms that U-Boot does not (yet) touch the reset line (like Clearfog GT-8K), it breaks PCIe (and boot) on the Macchiatobin. Revert commit 3d71746c42 ("PCI: armada8k: Add support for gpio controlled reset signal") entirely for now to fix the Macchaitobin regression. Proper PCIe reset support would require PCIe comphy setup support. That must wait for another kernel release. Reported-by: Sven Auhagen Signed-off-by: Baruch Siach --- v2: Add commit title to commit id mentions --- drivers/pci/controller/dwc/pcie-armada8k.c | 16 ---------------- 1 file changed, 16 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-armada8k.c b/drivers/pci/controller/dwc/pcie-armada8k.c index b171b6bc15c8..0c389a30ef5d 100644 --- a/drivers/pci/controller/dwc/pcie-armada8k.c +++ b/drivers/pci/controller/dwc/pcie-armada8k.c @@ -22,7 +22,6 @@ #include #include #include -#include #include "pcie-designware.h" @@ -30,7 +29,6 @@ struct armada8k_pcie { struct dw_pcie *pci; struct clk *clk; struct clk *clk_reg; - struct gpio_desc *reset_gpio; }; #define PCIE_VENDOR_REGS_OFFSET 0x8000 @@ -139,12 +137,6 @@ static int armada8k_pcie_host_init(struct pcie_port *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct armada8k_pcie *pcie = to_armada8k_pcie(pci); - if (pcie->reset_gpio) { - /* assert and then deassert the reset signal */ - gpiod_set_value_cansleep(pcie->reset_gpio, 1); - msleep(100); - gpiod_set_value_cansleep(pcie->reset_gpio, 0); - } dw_pcie_setup_rc(pp); armada8k_pcie_establish_link(pcie); @@ -257,14 +249,6 @@ static int armada8k_pcie_probe(struct platform_device *pdev) goto fail_clkreg; } - /* Get reset gpio signal and hold asserted (logically high) */ - pcie->reset_gpio = devm_gpiod_get_optional(dev, "reset", - GPIOD_OUT_HIGH); - if (IS_ERR(pcie->reset_gpio)) { - ret = PTR_ERR(pcie->reset_gpio); - goto fail_clkreg; - } - platform_set_drvdata(pdev, pcie); ret = armada8k_add_pcie_port(pcie, pdev);