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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE158C282C0 for ; Fri, 25 Jan 2019 11:58:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC43A218D0 for ; Fri, 25 Jan 2019 11:58:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726026AbfAYL6d (ORCPT ); Fri, 25 Jan 2019 06:58:33 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:46044 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725909AbfAYL6d (ORCPT ); Fri, 25 Jan 2019 06:58:33 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5D052EBD; Fri, 25 Jan 2019 03:58:32 -0800 (PST) Received: from e107981-ln.cambridge.arm.com (e107981-ln.cambridge.arm.com [10.1.197.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6C5D13F5AF; Fri, 25 Jan 2019 03:58:30 -0800 (PST) Date: Fri, 25 Jan 2019 11:58:25 +0000 From: Lorenzo Pieralisi To: Baruch Siach Cc: Thomas Petazzoni , Bjorn Helgaas , Andrew Lunn , Sven Auhagen , Jason Cooper , linux-pci@vger.kernel.org, Gregory Clement , Russell King , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth Subject: Re: [PATCH v2] Revert "PCI: armada8k: Add support for gpio controlled reset signal" Message-ID: <20190125115824.GA15799@e107981-ln.cambridge.arm.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, Jan 24, 2019 at 11:42:45PM +0200, Baruch Siach wrote: > 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. I have applied it and will send it upstream but please do test changes and make sure u-boot configurations are consistent, this commit log does not look promising in that respect. Thanks, Lorenzo > 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); > -- > 2.20.1 > 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 X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6ACBC282C0 for ; 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Fri, 25 Jan 2019 03:58:30 -0800 (PST) Date: Fri, 25 Jan 2019 11:58:25 +0000 From: Lorenzo Pieralisi To: Baruch Siach Subject: Re: [PATCH v2] Revert "PCI: armada8k: Add support for gpio controlled reset signal" Message-ID: <20190125115824.GA15799@e107981-ln.cambridge.arm.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190125_035834_904679_5CF74878 X-CRM114-Status: GOOD ( 18.80 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Lunn , Sven Auhagen , Jason Cooper , linux-pci@vger.kernel.org, Gregory Clement , Russell King , Thomas Petazzoni , Bjorn Helgaas , linux-arm-kernel@lists.infradead.org, Sebastian Hesselbarth Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Jan 24, 2019 at 11:42:45PM +0200, Baruch Siach wrote: > 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. I have applied it and will send it upstream but please do test changes and make sure u-boot configurations are consistent, this commit log does not look promising in that respect. Thanks, Lorenzo > 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); > -- > 2.20.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel