From patchwork Thu May 16 05:52:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Manikanta Maddireddy X-Patchwork-Id: 10945665 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 B74F2933 for ; Thu, 16 May 2019 05:54:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A777E28AAF for ; Thu, 16 May 2019 05:54:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9B15D28AB1; Thu, 16 May 2019 05:54:03 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 3439328AAF for ; Thu, 16 May 2019 05:54:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726466AbfEPFyC (ORCPT ); Thu, 16 May 2019 01:54:02 -0400 Received: from hqemgate16.nvidia.com ([216.228.121.65]:15042 "EHLO hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726277AbfEPFyC (ORCPT ); Thu, 16 May 2019 01:54:02 -0400 Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Wed, 15 May 2019 22:53:55 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Wed, 15 May 2019 22:53:59 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Wed, 15 May 2019 22:53:59 -0700 Received: from HQMAIL101.nvidia.com (172.20.187.10) by HQMAIL104.nvidia.com (172.18.146.11) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 16 May 2019 05:53:59 +0000 Received: from manikanta-bm2.nvidia.com (10.124.1.5) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server id 15.0.1473.3 via Frontend Transport; Thu, 16 May 2019 05:53:56 +0000 From: Manikanta Maddireddy To: , , , , , , CC: , , , Manikanta Maddireddy Subject: [PATCH V4 13/28] PCI: tegra: Increase the deskew retry time Date: Thu, 16 May 2019 11:22:52 +0530 Message-ID: <20190516055307.25737-14-mmaddireddy@nvidia.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190516055307.25737-1-mmaddireddy@nvidia.com> References: <20190516055307.25737-1-mmaddireddy@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1557986035; bh=IEjv2rSP2jvUnERcogfyAm21azs6yVKE9DYuM5TILsA=; h=X-PGP-Universal:From:To:CC:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:X-NVConfidentiality:MIME-Version: Content-Type; b=aCVJ2LZEzlutSPys+gdpbxthb8UOZHszgivh03ZlKqZ2tEArNZ4rAQKGOSkiN11l2 9iRDoCsc0kc0GqzvVI3ET/h1bUQrdhC6WvAOkRtmxVN70Jt+h6DfsQF2VrAP7XHkOP oK7sgxQoZPDvN10cErpZv47C1piISUc3TswaZ1Cp7WrL5T9Z5/bzF2B3uBEb2j3VZI 7IlZqW2yihQhirJ+5vfdkrjSQRej38c8rlpkIZso1tsNcmmnxhmFlcVF6zx1hPx2HA akb6/6YuyTewwt+OoC9f99c/4k13FcoagkTX4Zi8HWMwn6i2JBG1MNR7CehZn+SDcu uQieqRcjR3rvw== 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 Sometimes link speed change from Gen2 to Gen1 fails due to instability in deskew logic on lane-0 in Tegra210. Increase the deskew retry time to resolve this issue. Signed-off-by: Manikanta Maddireddy Acked-by: Thierry Reding --- V4: No change V3: No change V2: Took care of typos in commit log and coding style comments. drivers/pci/controller/pci-tegra.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 96cd75821872..9c28f1d9f177 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -209,6 +209,10 @@ #define RP_VEND_XP_OPPORTUNISTIC_ACK (1 << 27) #define RP_VEND_XP_OPPORTUNISTIC_UPDATEFC (1 << 28) +#define RP_VEND_CTL0 0x00000f44 +#define RP_VEND_CTL0_DSK_RST_PULSE_WIDTH_MASK (0xf << 12) +#define RP_VEND_CTL0_DSK_RST_PULSE_WIDTH (0x9 << 12) + #define RP_VEND_CTL1 0x00000f48 #define RP_VEND_CTL1_ERPT (1 << 13) @@ -305,6 +309,7 @@ struct tegra_pcie_soc { bool force_pca_enable; bool program_uphy; bool update_clamp_threshold; + bool program_deskew_time; struct { struct { u32 rp_ectl_2_r1; @@ -620,6 +625,24 @@ static void tegra_pcie_program_ectl_settings(struct tegra_pcie_port *port) writel(value, port->base + RP_ECTL_6_R2); } +static void tegra_pcie_apply_sw_fixup(struct tegra_pcie_port *port) +{ + const struct tegra_pcie_soc *soc = port->pcie->soc; + u32 value; + + /* + * Sometimes link speed change from Gen2 to Gen1 fails due to + * instability in deskew logic on lane-0. Increase the deskew + * retry time to resolve this issue. + */ + if (soc->program_deskew_time) { + value = readl(port->base + RP_VEND_CTL0); + value &= ~RP_VEND_CTL0_DSK_RST_PULSE_WIDTH_MASK; + value |= RP_VEND_CTL0_DSK_RST_PULSE_WIDTH; + writel(value, port->base + RP_VEND_CTL0); + } +} + static void tegra_pcie_port_enable(struct tegra_pcie_port *port) { unsigned long ctrl = tegra_pcie_port_get_pex_ctrl(port); @@ -649,6 +672,8 @@ static void tegra_pcie_port_enable(struct tegra_pcie_port *port) if (soc->ectl.enable) tegra_pcie_program_ectl_settings(port); + + tegra_pcie_apply_sw_fixup(port); } static void tegra_pcie_port_disable(struct tegra_pcie_port *port) @@ -2356,6 +2381,7 @@ static const struct tegra_pcie_soc tegra20_pcie = { .force_pca_enable = false, .program_uphy = true, .update_clamp_threshold = false, + .program_deskew_time = false, .ectl.enable = false, }; @@ -2381,6 +2407,7 @@ static const struct tegra_pcie_soc tegra30_pcie = { .force_pca_enable = false, .program_uphy = true, .update_clamp_threshold = false, + .program_deskew_time = false, .ectl.enable = false, }; @@ -2399,6 +2426,7 @@ static const struct tegra_pcie_soc tegra124_pcie = { .force_pca_enable = false, .program_uphy = true, .update_clamp_threshold = true, + .program_deskew_time = false, .ectl.enable = false, }; @@ -2417,6 +2445,7 @@ static const struct tegra_pcie_soc tegra210_pcie = { .force_pca_enable = true, .program_uphy = true, .update_clamp_threshold = true, + .program_deskew_time = true, .ectl = { .regs = { .rp_ectl_2_r1 = 0x0000000f, @@ -2454,6 +2483,7 @@ static const struct tegra_pcie_soc tegra186_pcie = { .force_pca_enable = false, .program_uphy = false, .update_clamp_threshold = false, + .program_deskew_time = false, .ectl.enable = false, };