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=-8.9 required=3.0 tests=DATE_IN_FUTURE_06_12, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 83476C67838 for ; Mon, 10 Dec 2018 02:44:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 51A3A2082F for ; Mon, 10 Dec 2018 02:44:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 51A3A2082F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=microchip.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-pci-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726488AbeLJCon (ORCPT ); Sun, 9 Dec 2018 21:44:43 -0500 Received: from mail-eopbgr750079.outbound.protection.outlook.com ([40.107.75.79]:23180 "EHLO NAM02-BL2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726461AbeLJCom (ORCPT ); Sun, 9 Dec 2018 21:44:42 -0500 Received: from BN6PR19CA0089.namprd19.prod.outlook.com (2603:10b6:404:133::27) by DM5PR19MB1322.namprd19.prod.outlook.com (2603:10b6:3:bf::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1404.21; Mon, 10 Dec 2018 02:44:40 +0000 Received: from BY2FFO11FD009.protection.gbl (2a01:111:f400:7c0c::158) by BN6PR19CA0089.outlook.office365.com (2603:10b6:404:133::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1404.19 via Frontend Transport; Mon, 10 Dec 2018 02:44:40 +0000 Authentication-Results: spf=softfail (sender IP is 208.19.99.221) smtp.mailfrom=microchip.com; vger.kernel.org; dkim=none (message not signed) header.d=none;vger.kernel.org; dmarc=none action=none header.from=microchip.com; Received-SPF: SoftFail (protection.outlook.com: domain of transitioning microchip.com discourages use of 208.19.99.221 as permitted sender) Received: from AUSMBX1.microsemi.net (208.19.99.221) by BY2FFO11FD009.mail.protection.outlook.com (10.1.14.73) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.1404.13 via Frontend Transport; Mon, 10 Dec 2018 02:44:40 +0000 Received: from AUSMBX3.microsemi.net (10.201.34.33) by AUSMBX1.microsemi.net (10.201.34.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1531.3; Sun, 9 Dec 2018 20:14:31 -0600 Received: from server1.microsemi.net (10.188.116.209) by ausmbx3.microsemi.net (10.201.34.33) with Microsoft SMTP Server id 15.1.1531.3 via Frontend Transport; Sun, 9 Dec 2018 20:14:29 -0600 From: Wesley Sheng To: , , , , CC: , Subject: [PATCH 4/5] switchtec: Improve MRPC efficiency by leveraging write combining Date: Mon, 10 Dec 2018 17:12:23 +0800 Message-ID: <1544433144-7563-5-git-send-email-wesley.sheng@microchip.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1544433144-7563-1-git-send-email-wesley.sheng@microchip.com> References: <1544433144-7563-1-git-send-email-wesley.sheng@microchip.com> MIME-Version: 1.0 Content-Type: text/plain X-EOPAttributedMessage: 0 X-Matching-Connectors: 131888834803174920;(5a93feec-e11d-4f7b-166a-08d09f1f276b);() X-Forefront-Antispam-Report: CIP:208.19.99.221;IPV:NLI;CTRY:US;EFV:NLI;SFV:NSPM;SFS:(10009020)(396003)(376002)(39850400004)(136003)(346002)(2980300002)(189003)(199004)(316002)(16586007)(97736004)(110136005)(54906003)(105596002)(50226002)(50466002)(486006)(68736007)(2906002)(106466001)(44832011)(5660300001)(8936002)(36756003)(48376002)(4326008)(53936002)(51416003)(107886003)(69596002)(446003)(126002)(2616005)(476003)(14444005)(11346002)(356004)(6666004)(47776003)(336012)(2201001)(498600001)(305945005)(81156014)(81166006)(76176011)(86362001)(26005)(77096007)(8676002)(450100002)(53416004);DIR:OUT;SFP:1101;SCL:1;SRVR:DM5PR19MB1322;H:AUSMBX1.microsemi.net;FPR:;SPF:SoftFail;LANG:en;PTR:InfoDomainNonexistent;MX:1;A:1; X-Microsoft-Exchange-Diagnostics: 1;BY2FFO11FD009;1:gpe02ZTZRhFAqJsZ4NJZTl5kqe9d5ipuD81Hd5/ag0Z79iEm3yPh2r+o14VHHFNXPWIhFuPgR7AyhigW94D2IfFJetJU/j8aT10oYUe/0bCaKMRpQRUqDaDEKqUOX067 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 550812f8-a0a9-4678-a44e-08d65e496eb3 X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:(2390098)(7020095)(5600074)(711020)(2017052603328);SRVR:DM5PR19MB1322; X-Microsoft-Exchange-Diagnostics: 1;DM5PR19MB1322;3:DwJWBzQxt0bXtctoSMI32I/6FzWNMWYckeKPfZo/F5Zl1winhFyyjQditziuMkqp/+o5PAjLY0uhMzvrs9kwTXSajwqAHWbS0lkFvZVuXkM38dup2J+iKPOezc5fIAavUsxsXrphxMw2L2RtDlo54Y3XcQOQIx0OKE9FZ8pXHG2ZjZ31lMxGxDb09jucTtIQnQB1imInsHyzZdKd4OWAJ/i0Tra1Ka0zGA7BOVd1NZOTQVAHEW2aQF2IVVfdVLOKLrKJsuc9xefrwnqD9mMetCo6oVdBaF5nK28RrM9N4LDVQwqoepf6T8J9iIBvW2IjEShLaICH5Ee4JcOHWLUPh9Fs64VSnSYZgCKiBM7Cqt4=;25:pOoFl9jvoJ/ghRoqhJ7gku2UrrGIPUSa7c8NTdobaSFUF6+5a7E0zka0+QFVDTQb2mf+ecuFjp7VErCpfOYZUcsdBtwiZK8PV5nNbi3NyGVNTUXz7eEXUg1nSZHoGTsWkU/IGGB6jt7z8Pjh4uCKznR9Kwrk0kkiWqcfCFwjuPmgrUtSCaCRqzu0dNEut5Jx/LoLtqDbSd5LES/1qKr13wU4gIdsgyuF7G9OfPTMq/HjEHUL83boGt4H53sjyJ35hgUrcN/psgnYj0BEzNh0wWcS5FqG0/B4SG1yC62cZGDeZ58ZkYpv9sJ+p6TY+aenrX3IRJ/D4EUQ0RMIIImmQw== X-MS-TrafficTypeDiagnostic: DM5PR19MB1322: X-Microsoft-Exchange-Diagnostics: 1;DM5PR19MB1322;31:nXjb+E/NoMClyN3D/PpxDJgYlCXULUvGdxEr0DBaZuceH3gX1TYlkVp7l/DgLJbhq638JJpFVvZ1+8LsSmyH7n01qt5E7rPCS+Ls4+eV4W74zHxdVS4OoXtjqSSTr1MiKZz0gzK4b7P41PNvP/sMggfcnNZ/ZgVguZ4jHBkG7i3BfSDT/lvWBdpE54/wySnlTfgHCM9r7NnqacyWfqvZb+Pb20EA6613JU3wKeGxMYc=;4:+BDyp7B9GeY4z/cPcCPx3+DOqJTllhRzpLIHzoSs0NItuhbPWFqYaJkO6cEHoL39s+VGP52GSYLJZktRW9SiYgc0gUslVahbiWdL0WVIuPtVDng6cTEAk3nsHy8Ci6ao87q4ExpslYqmlcdBemAzeILhXRGSj59JiwU8qEAQb6RtsX7PNYmqqDhNbP0Fohts3l/0NWSOan7DFsQXJs6N8timsQw12ZiyYrwXDW2KvfoSv/FImlQ6Oz/KYFxdZ6XHYoBxPOzfPj6nZAbqMROfwQ== X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(6095135)(2401047)(8121501046)(5005006)(93006095)(93001095)(10201501046)(3002001)(3231455)(999002)(944501520)(52105112)(6055026)(148016)(6096035)(20161123556025)(20161123561025)(20161123563025)(201703131430075)(201703131448075)(201703131433075)(201703151042153)(20161123559100)(20161123565025)(201708071742011)(7699051)(76991095);SRVR:DM5PR19MB1322;BCL:0;PCL:0;RULEID:(400006);SRVR:DM5PR19MB1322; X-Forefront-PRVS: 08828D20BC X-Microsoft-Exchange-Diagnostics: =?us-ascii?Q?1;DM5PR19MB1322;23:QHKFO5sygocHyqRVrdGeY7dApZQTLdOXQ1qHGhM4C?= =?us-ascii?Q?ssMeAO3oxDM808kbW8SZujspp/CVbvl3uUbXhUx69xEdZOHWkmbhfBPDuDuI?= =?us-ascii?Q?xaCviIYP1U6rI+G8T5X5VaueEb7jZ8sDPZt7URwk1gb5J0uaID3hFfvj+uSz?= =?us-ascii?Q?9iVjPtt47FKqoQk9yNyOm55PAD+NoXWtd7SZsDs825hi5yv7SANX1lqv38xy?= =?us-ascii?Q?XmI3paRtrRz+d5tQ7L6qiauIWztJkMLPnjxGwDIAaPD/+R3RA0fo7HBX9146?= =?us-ascii?Q?mZAoXFYTWMU09nHuYRRrd+GDhQ6+YR3AaG2Grr08KhJFhQ5FE1Wa45smgbdb?= =?us-ascii?Q?/cPW5SH9xh12WHkdOol5IJFzW7pegT0CZubfZKicslBGsw5RcWCHMBs9M1w9?= =?us-ascii?Q?kbU9+HwQxEVjHDhIezUKsZPa3y/N8eEH+its7pDOQx42mtVh3thmyuOZEV8I?= =?us-ascii?Q?eXuWfG/IXDgXfoLhB3664dBZfRGcZYNBVpfYgtMiae40U3FCOLnTjxMgr013?= =?us-ascii?Q?GY7oq0y4HVEYj0bvGVgZWndnCLigimuFjy/TaQRBKSWbPs4ErEpcF0X6xWnF?= =?us-ascii?Q?YEkiW3iieE3JjVsWnHulbF/WGf3S9lV+Mbwi5IVzF7h+YH3SAF7UR46Tin5O?= =?us-ascii?Q?CR4KHCOZu+JOlmVKs9czl2IyeybmUoO3bpQ2BJO/UwccPpExvRRIu12NtbKB?= =?us-ascii?Q?DO4o4r2tfa/ksoIK8cc7sCYH0VtWwYzOPdO7WekexlHh2CerawtHyVpTLgbO?= =?us-ascii?Q?PgGxuU0s0/WqzSvnRDGy58Eet/kW04+uFHhAZvVWaA4e9KUGc/ZV57A1mDYs?= =?us-ascii?Q?e8RP6DZbBDum/CXvAqwwMXsnua5vi7a9+PmIlyRyt8sWsSmiqJuxm+yq4XxF?= =?us-ascii?Q?CMwg9mXLdvDtbGDJL1nn3CGh9Q6H6zvkiWTNZ+POjHh6Ltr+FWRKjYWeqGrW?= =?us-ascii?Q?NAkj/5I4FqI1QzK14BrK6YaRVfiK1BmhB8QV9G/xpRF+uJPw8qW5qPo+Zpox?= =?us-ascii?Q?70QSmPpiVAgNirhignRteMvKJ0mr4VoUVSwZCDQT1KuUyC7nwbrtmra4HDbd?= =?us-ascii?Q?PbY3TISyUQKsaKP8fJZXbvR8ipJvCsgYkRaev0TQN5vQv9baB2oHUP+LihRK?= =?us-ascii?Q?qImJq4rzZyc1IJr1/+RK35X7kQQDi7xljsV39W6GJA4abm25pFL/Q=3D=3D?= X-Microsoft-Antispam-Message-Info: hnthwzDNFUmoW8ePGrWxtTpm4jjotZWEaLyvYBvRdopF8HocQ8TpIXbC35lty3kg2YY25QZ+EAmpi6gESypRCfE52zZ34UcG7xFOFyx4muXKPMn1Q5Lmu9RgNH1TX2Y5bVrHR9x54XAU9Lvf0ERCW5lo/n4CFvEgt8GeYWwrkaouQ/CpVn4y17JE9KeFb6c0QfB2oC7/bPVIEJxO+/8kEo6jS65st7fCZCedtBBFFUQE1FpEJOGgvqcMe0h8MD+WSheWKTfbdiQIltizT35yOG/UJx0602uKwDZ/aTq9T8S7Y8pqEm5NzRiAb0q+9cYL22FG8iygmGtP1f3VWED8EDXf9sw7mFYOIKAOGiaRj3A= X-Microsoft-Exchange-Diagnostics: 1;DM5PR19MB1322;6:RPtq0FsZ321Og9WZPwqzjNsTNBP2uXvxc1Ec8wFW0+dHyWe7sdc3P9dGbevE3uxtf5AY1n4M9c6gS6MgR++PFzAI/8xcmSb9XeDdXLElHH+6WQ25N32YELNTRKmiiSATT1z3DDqB3js9bC2bRpk9+pCE/1Ub7A5gaOHR5b59k+5SUUJEYjZRWQLhGt2gpwtj/pWRzOg/zH8MvLw1YthLGM377CG5qk0Nxo+OX1I93tLJXqzCGsLgg4gVRueM7Cw4RL1+2P7iIkgNufrQ9Ho3i1tWgexa93AX5j65rhbXZrBthPtle0ILBMB5sOFX45J0VEAGXRrO3KQSVKgrbcGxiciKJn/OqNvb3RqA2TOeS9MHUKlEcGrr/gKXpUbVVz9osczyRQ3QSflSMOfQBpXTeeVNOSboLr+tkJJIitdvNUMvGIWVuji2OCJXZ/yhcG9g9VeJEAjcz1A8A8IB2sl7oQ==;5:8AiiSwtbaSw3UaWgouOOL/cGxQlCQJ/fTj4WJQ6WiLKKi29LYHIPLk8pr1VxbjyykjlihyPg+jCcL0Y1ZCF6SreUUSMy9Ca3FcH9hw8ZwhQmtZEPQ7soDV8vYsUsEbPcqf2THHagaEiT0naJf1MXa4vvZbhTUCs7kltbgorRNkg=;7:xWCjbWYGQx/yH7ZDdaNLNhr3nyrhHylsyi1a2OZa3eg9BbRNJ0vT3RJDeGbn3cR4guUK8uw7xSUQvxrXQRl7UWG97cA1Hm1of522fV1Tl4ue39UlE12abuthT8Sz1OhZ4/V3mR7rg3boO+hwFqbO2g== SpamDiagnosticOutput: 1:99 SpamDiagnosticMetadata: NSPM X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Dec 2018 02:44:40.1144 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 550812f8-a0a9-4678-a44e-08d65e496eb3 X-MS-Exchange-CrossTenant-Id: 5afe0b00-7697-4969-b663-5eab37d5f47e X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=5afe0b00-7697-4969-b663-5eab37d5f47e;Ip=[208.19.99.221];Helo=[AUSMBX1.microsemi.net] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR19MB1322 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Kelvin Cao MRPC Input buffer is mostly memory without any side effects, thus we can improve the access time by enabling write combining on only this region of the BAR. In a few places, we still need to flush the WC buffer. To do this, we simply read from the Outbound Doorbell register seeing reads to this register are processed by low latency hardware. Signed-off-by: Kelvin Cao Signed-off-by: Wesley Sheng Reviewed-by: Logan Gunthorpe --- drivers/pci/switch/switchtec.c | 41 +++++++++++++++++++++++++++++++++++------ 1 file changed, 35 insertions(+), 6 deletions(-) diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c index a908670..0b8862b 100644 --- a/drivers/pci/switch/switchtec.c +++ b/drivers/pci/switch/switchtec.c @@ -113,6 +113,19 @@ static void stuser_set_state(struct switchtec_user *stuser, static void mrpc_complete_cmd(struct switchtec_dev *stdev); +static void flush_wc_buf(struct switchtec_dev *stdev) +{ + struct ntb_dbmsg_regs __iomem *mmio_dbmsg; + + /* + * odb (outbound doorbell) register is processed by low latency + * hardware and w/o side effect + */ + mmio_dbmsg = (void __iomem *)stdev->mmio_ntb + + SWITCHTEC_NTB_REG_DBMSG_OFFSET; + ioread32(&mmio_dbmsg->odb); +} + static void mrpc_cmd_submit(struct switchtec_dev *stdev) { /* requires the mrpc_mutex to already be held when called */ @@ -132,6 +145,7 @@ static void mrpc_cmd_submit(struct switchtec_dev *stdev) stdev->mrpc_busy = 1; memcpy_toio(&stdev->mmio_mrpc->input_data, stuser->data, stuser->data_len); + flush_wc_buf(stdev); iowrite32(stuser->cmd, &stdev->mmio_mrpc->cmd); schedule_delayed_work(&stdev->mrpc_timeout, @@ -1231,23 +1245,38 @@ static int switchtec_init_pci(struct switchtec_dev *stdev, struct pci_dev *pdev) { int rc; + void __iomem *map; + unsigned long res_start, res_len; rc = pcim_enable_device(pdev); if (rc) return rc; - rc = pcim_iomap_regions(pdev, 0x1, KBUILD_MODNAME); - if (rc) - return rc; - rc = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64)); if (rc) return rc; pci_set_master(pdev); - stdev->mmio = pcim_iomap_table(pdev)[0]; - stdev->mmio_mrpc = stdev->mmio + SWITCHTEC_GAS_MRPC_OFFSET; + res_start = pci_resource_start(pdev, 0); + res_len = pci_resource_len(pdev, 0); + + if (!devm_request_mem_region(&pdev->dev, res_start, + res_len, KBUILD_MODNAME)) + return -EBUSY; + + stdev->mmio_mrpc = devm_ioremap_wc(&pdev->dev, res_start, + SWITCHTEC_GAS_TOP_CFG_OFFSET); + if (!stdev->mmio_mrpc) + return -ENOMEM; + + map = devm_ioremap(&pdev->dev, + res_start + SWITCHTEC_GAS_TOP_CFG_OFFSET, + res_len - SWITCHTEC_GAS_TOP_CFG_OFFSET); + if (!map) + return -ENOMEM; + + stdev->mmio = map - SWITCHTEC_GAS_TOP_CFG_OFFSET; stdev->mmio_sw_event = stdev->mmio + SWITCHTEC_GAS_SW_EVENT_OFFSET; stdev->mmio_sys_info = stdev->mmio + SWITCHTEC_GAS_SYS_INFO_OFFSET; stdev->mmio_flash_info = stdev->mmio + SWITCHTEC_GAS_FLASH_INFO_OFFSET; -- 2.7.4