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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 75816C0015E for ; Fri, 14 Jul 2023 06:47:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:CC:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=b23wVbZQjoo0LluX5YaSWBTz+M1wQctiZx8iYaJo2Sw=; b=2lPKveqirGs3Bz fJpfUocKcCJzD5mDkMy7Ze46pcm0wC0CxzDVygIrC2d9/eI1tjPcRtQZE0CUiDyIsoPXV8iNf08At tB8y/ahUUNz+oY0NXk8Oz8jrkXnsx2FhtQWj0b7Ni/yQ/74ZMrqbJjdKfmrhJ4p3/fHgfxB93hfzg l110ydOqkDCrRFoOCHAdrAwcnVd1wZ5VbrGcDXEOyVG84vbtyVwcAveDFk3uD7nXznxyqB8PMvpKd e0V9mP/sM+T53HgCgD3Okpz5mi0pAYoqHT67nVQS8zpRju2+Riz+uB30mTWkMqSHU5wUn6/a2xQ1+ wp+EcEzELhUTEGr0guQQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qKCZa-005Cj7-3D; Fri, 14 Jul 2023 06:46:39 +0000 Received: from fllv0015.ext.ti.com ([198.47.19.141]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qKCZT-005Cfh-2T for linux-arm-kernel@lists.infradead.org; Fri, 14 Jul 2023 06:46:33 +0000 Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 36E6kBnn116158; Fri, 14 Jul 2023 01:46:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1689317171; bh=51ygtQqbjia4BNqCGeTzY/PWLEnrB51JEBAW1iWjYps=; h=Date:Subject:To:CC:References:From:In-Reply-To; b=fJ+J0NHdY++G9H2fThwS039bgwc1y5MWHuZByQxeVy3Sow7VUXgkHMEvZkmZ8A4Bg M5qln6ojA518kKzyjtG0oaLuqQW9hc1mYIAXCQ8dNlmBx0O2T0jflGRrejO1P8HG1S 2Wt+ZmSw0O8x2RfviukuPK8JC3dWVXViWUkJHJfM= Received: from DFLE109.ent.ti.com (dfle109.ent.ti.com [10.64.6.30]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 36E6kBwa051681 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 14 Jul 2023 01:46:11 -0500 Received: from DFLE104.ent.ti.com (10.64.6.25) by DFLE109.ent.ti.com (10.64.6.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Fri, 14 Jul 2023 01:46:11 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE104.ent.ti.com (10.64.6.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Fri, 14 Jul 2023 01:46:11 -0500 Received: from [172.24.19.15] (ileaxei01-snat.itg.ti.com [10.180.69.5]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 36E6k7RU097881; Fri, 14 Jul 2023 01:46:08 -0500 Message-ID: Date: Fri, 14 Jul 2023 12:16:07 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH v3] PCI: j721e: Delay 100ms T_PVPERL from power stable to PERST# inactive To: Vignesh Raghavendra , Lorenzo Pieralisi , Krzysztof Wilczy_ski , Rob Herring , Bjorn Helgaas CC: , , , , Achal Verma References: <20230707095119.447952-1-a-verma1@ti.com> Content-Language: en-US From: "Verma, Achal" In-Reply-To: <20230707095119.447952-1-a-verma1@ti.com> X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230713_234631_950117_A7B169CE X-CRM114-Status: GOOD ( 19.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 7/7/2023 3:21 PM, Achal Verma wrote: > As per the PCIe Card Electromechanical specification REV. 5.0, PERST# > signal should be de-asserted after minimum 100ms from the time power-rails > become stable. So, to ensure 100ms delay to give sufficient time for > power-rails and refclk to become stable, change delay from 100us to 100ms. > > From PCIe Card Electromechanical specification REV. 5.0 section 2.9.2: > TPVPERL: Power stable to PERST# inactive - 100ms > > Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") > Signed-off-by: Achal Verma Hello Bjorn, Could you please bless this with "Reviewed-by" tag. Thanks, Achal Verma > --- > > Changes from v2: > * Fix commit message. > > Change from v1: > * Add macro for delay value. > > drivers/pci/controller/cadence/pci-j721e.c | 11 +++++------ > drivers/pci/pci.h | 2 ++ > 2 files changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c > index e70213c9060a..32b6a7dc3cff 100644 > --- a/drivers/pci/controller/cadence/pci-j721e.c > +++ b/drivers/pci/controller/cadence/pci-j721e.c > @@ -498,14 +498,13 @@ static int j721e_pcie_probe(struct platform_device *pdev) > > /* > * "Power Sequencing and Reset Signal Timings" table in > - * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 3.0 > - * indicates PERST# should be deasserted after minimum of 100us > - * once REFCLK is stable. The REFCLK to the connector in RC > - * mode is selected while enabling the PHY. So deassert PERST# > - * after 100 us. > + * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 5.0 > + * indicates PERST# should be deasserted after minimum of 100ms > + * after power rails achieve specified operating limits and > + * within this period reference clock should also become stable. > */ > if (gpiod) { > - usleep_range(100, 200); > + msleep(PCIE_TPVPERL_DELAY_MS); > gpiod_set_value_cansleep(gpiod, 1); > } > > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index a4c397434057..6ab2367e5867 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -13,6 +13,8 @@ > > #define PCIE_LINK_RETRAIN_TIMEOUT_MS 1000 > > +#define PCIE_TPVPERL_DELAY_MS 100 /* see PCIe CEM r5.0, sec 2.9.2 */ > + > extern const unsigned char pcie_link_speed[]; > extern bool pci_early_dump; > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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 fllv0015.ext.ti.com ([198.47.19.141]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qKCZT-005Cfh-2T for linux-arm-kernel@lists.infradead.org; Fri, 14 Jul 2023 06:46:33 +0000 Message-ID: Date: Fri, 14 Jul 2023 12:16:07 +0530 MIME-Version: 1.0 Subject: Re: [PATCH v3] PCI: j721e: Delay 100ms T_PVPERL from power stable to PERST# inactive References: <20230707095119.447952-1-a-verma1@ti.com> Content-Language: en-US From: "Verma, Achal" In-Reply-To: <20230707095119.447952-1-a-verma1@ti.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+lwn-linux-arm-kernel=archive.lwn.net@lists.infradead.org List-Archive: To: Vignesh Raghavendra , Lorenzo Pieralisi , Krzysztof Wilczy_ski , Rob Herring , Bjorn Helgaas Cc: linux-omap@vger.kernel.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Achal Verma Message-ID: <20230714064607.aPyFm2m509QBY7zYD4B74sl9jwSzWJdCLjJZwfJNogM@z> On 7/7/2023 3:21 PM, Achal Verma wrote: > As per the PCIe Card Electromechanical specification REV. 5.0, PERST# > signal should be de-asserted after minimum 100ms from the time power-rails > become stable. So, to ensure 100ms delay to give sufficient time for > power-rails and refclk to become stable, change delay from 100us to 100ms. > > From PCIe Card Electromechanical specification REV. 5.0 section 2.9.2: > TPVPERL: Power stable to PERST# inactive - 100ms > > Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") > Signed-off-by: Achal Verma Hello Bjorn, Could you please bless this with "Reviewed-by" tag. Thanks, Achal Verma > --- > > Changes from v2: > * Fix commit message. > > Change from v1: > * Add macro for delay value. > > drivers/pci/controller/cadence/pci-j721e.c | 11 +++++------ > drivers/pci/pci.h | 2 ++ > 2 files changed, 7 insertions(+), 6 deletions(-) > > diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c > index e70213c9060a..32b6a7dc3cff 100644 > --- a/drivers/pci/controller/cadence/pci-j721e.c > +++ b/drivers/pci/controller/cadence/pci-j721e.c > @@ -498,14 +498,13 @@ static int j721e_pcie_probe(struct platform_device *pdev) > > /* > * "Power Sequencing and Reset Signal Timings" table in > - * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 3.0 > - * indicates PERST# should be deasserted after minimum of 100us > - * once REFCLK is stable. The REFCLK to the connector in RC > - * mode is selected while enabling the PHY. So deassert PERST# > - * after 100 us. > + * PCI EXPRESS CARD ELECTROMECHANICAL SPECIFICATION, REV. 5.0 > + * indicates PERST# should be deasserted after minimum of 100ms > + * after power rails achieve specified operating limits and > + * within this period reference clock should also become stable. > */ > if (gpiod) { > - usleep_range(100, 200); > + msleep(PCIE_TPVPERL_DELAY_MS); > gpiod_set_value_cansleep(gpiod, 1); > } > > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index a4c397434057..6ab2367e5867 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -13,6 +13,8 @@ > > #define PCIE_LINK_RETRAIN_TIMEOUT_MS 1000 > > +#define PCIE_TPVPERL_DELAY_MS 100 /* see PCIe CEM r5.0, sec 2.9.2 */ > + > extern const unsigned char pcie_link_speed[]; > extern bool pci_early_dump; > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel