From patchwork Thu Dec 14 07:28:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Minda Chen X-Patchwork-Id: 13492503 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 BB95CC4167D for ; Thu, 14 Dec 2023 07:30:18 +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-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hRrY39Dgu318XcHM2uIuYoQvPAri5IdHhmyEwQDubak=; b=pC/Ak6RAFoggFP TmPcWfNZv0oaRTER/E4iflqZCOFRZVWEUW0+XgxPAN7288QZsmX6Ew/tlcvrJGL/lsyvNqqTS+7rA OYj9eWTsO9uGWJ+sD+LkkSqizKYKy0oZPXzdGEH5Bb+FiEMeakD0KYjaIfQtuA/ql+LLeg50DhvKd EHgxrzbxxfjtM0GQywWS6G5RvEDROADmMMD4uMbjCpl9roeqfBWqpWnOlwgf3mxRl8NxNBohve8FR 8gAlSaIaG8EfL6DUg1V1PTtFGtFa7A0FWkXMcnj2qV56AdHMLT8/DzEoCC2gsNeAgMu+rwY3mntHO YJq/CsbPjhCyssB6XJmw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rDgAe-00H6hV-34; Thu, 14 Dec 2023 07:30:12 +0000 Received: from fd01.gateway.ufhost.com ([61.152.239.71]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rDgAT-00H6GA-0z for linux-riscv@lists.infradead.org; Thu, 14 Dec 2023 07:30:05 +0000 Received: from EXMBX166.cuchost.com (unknown [175.102.18.54]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "EXMBX166", Issuer "EXMBX166" (not verified)) by fd01.gateway.ufhost.com (Postfix) with ESMTP id 6514C8175; Thu, 14 Dec 2023 15:29:49 +0800 (CST) Received: from EXMBX171.cuchost.com (172.16.6.91) by EXMBX166.cuchost.com (172.16.6.76) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Thu, 14 Dec 2023 15:29:49 +0800 Received: from ubuntu.localdomain (113.72.145.168) by EXMBX171.cuchost.com (172.16.6.91) with Microsoft SMTP Server (TLS) id 15.0.1497.42; Thu, 14 Dec 2023 15:29:47 +0800 From: Minda Chen To: Conor Dooley , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Rob Herring , Bjorn Helgaas , Lorenzo Pieralisi , "Daire McNamara" , Emil Renner Berthing , Krzysztof Kozlowski CC: , , , , Paul Walmsley , Palmer Dabbelt , Albert Ou , Philipp Zabel , Mason Huo , Leyfoon Tan , Kevin Xie , Minda Chen Subject: [PATCH v13 19/21] PCI: Add PCIE_RESET_CONFIG_DEVICE_WAIT_MS waiting time value Date: Thu, 14 Dec 2023 15:28:37 +0800 Message-ID: <20231214072839.2367-20-minda.chen@starfivetech.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231214072839.2367-1-minda.chen@starfivetech.com> References: <20231214072839.2367-1-minda.chen@starfivetech.com> MIME-Version: 1.0 X-Originating-IP: [113.72.145.168] X-ClientProxiedBy: EXCAS064.cuchost.com (172.16.6.24) To EXMBX171.cuchost.com (172.16.6.91) X-YovoleRuleAgent: yovoleflag X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231213_233001_663798_4ACB4987 X-CRM114-Status: GOOD ( 11.42 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Kevin Xie Add the PCIE_RESET_CONFIG_DEVICE_WAIT_MS macro to define the minimum waiting time between exit from a conventional reset and sending the first configuration request to the device. As described in PCI base specification r6.0, section 6.6.1 , there are two different use cases of the value: - "With a Downstream Port that does not support Link speeds greater than 5.0 GT/s, software must wait a minimum of 100 ms following exit from a Conventional Reset before sending a Configuration Request to the device immediately below that Port." - "With a Downstream Port that supports Link speeds greater than 5.0 GT/s, software must wait a minimum of 100 ms after Link training completes before sending a Configuration Request to the device immediately below that Port." Signed-off-by: Kevin Xie Reviewed-by: Mason Huo Acked-by: Bjorn Helgaas --- drivers/pci/pci.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 5ecbcf041179..06f1f1eb878c 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -22,6 +22,22 @@ */ #define PCIE_PME_TO_L2_TIMEOUT_US 10000 +/* + * As described in PCI base specification r6.0, section 6.6.1 , there are two different use cases of the value: + * + * - "With a Downstream Port that does not support Link speeds greater + * than 5.0 GT/s, software must wait a minimum of 100 ms following exit + * from a Conventional Reset before sending a Configuration Request to + * the device immediately below that Port." + * + * - "With a Downstream Port that supports Link speeds greater than + * 5.0 GT/s, software must wait a minimum of 100 ms after Link training + * completes before sending a Configuration Request to the device + * immediately below that Port." + */ +#define PCIE_RESET_CONFIG_DEVICE_WAIT_MS 100 + extern const unsigned char pcie_link_speed[]; extern bool pci_early_dump;