From patchwork Wed Oct 19 11:07:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sherry Sun X-Patchwork-Id: 5316 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:4ac7:0:0:0:0:0 with SMTP id y7csp284774wrs; Wed, 19 Oct 2022 05:06:42 -0700 (PDT) X-Google-Smtp-Source: AMsMyM58CJ8OivDY1v3LDttApXiCqjeWmhgt2wHPcnUsdUkXBPbeBX1/wiNvuLeaUl627naS+mEP X-Received: by 2002:a62:e70f:0:b0:562:d556:8cf2 with SMTP id s15-20020a62e70f000000b00562d5568cf2mr8307147pfh.78.1666181202085; Wed, 19 Oct 2022 05:06:42 -0700 (PDT) ARC-Seal: i=2; a=rsa-sha256; t=1666181202; cv=pass; d=google.com; s=arc-20160816; b=WUp4h+NvOdaIW6bXmNv+6K66IXph0sSfwPELngb4iTRun5ZuInn5IvasT8oZHVIjsl AoKN3FfCBrdf4voDWA+Vb0z2A9sjbVGF6svwClZxmHHOBVh7aN09stptHrUIisaKSXrh DdsACbWSe2/c9TCgf584hI0Zo5zpX/w8UEgKgSMst1A6RkurwurOt8FHQEfb+sWsK9u4 OhK1ev0eiVbenJqFp4SBXjTke3f7bGerOSiyUBMDEoG0K5yFQszPIAPLr75dosfRTMDb +rGf5IXvuLFiVljxmB5tIHC7KODw7t/08u1vlPVDQwoZsHKlDdrY7EdsK/BoRfs/8sOc /O/A== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:message-id:date:subject:cc:to:from :dkim-signature; bh=w0MHtjuLOB0x6YIhxA9jVBY4QB9MitIGbu0U4g813ZI=; b=YIcOZhz8zNH6EiFaRDVrmD4Zifr/D4dvQ+07T/pyGQ/rlV0arp6PQT8xPOfOeFpx/c RyTYKrpB0zo33vRG4xVjbayArUCidjnjt8BBxJLd78OJaebipp6BC7tgo3bW+LShuXBx KigDPdj+Hn4BqS6ycZJRz5KDiY9GhDtT6BQ/CstctfryEj8ZAlzxcjFs6rPWY/z9CK64 BKFTQlHzCgNNa/l4PsgXNGPKIH8YG3a6aD6COZh7JYJA+9i1dh0m1a6bLaXO4+eQAedO I2mG6qyu2eT+zSAY/L1OZCSCVWEbgpNPd6jstKM/SqWhlssECcu1tmN/rHJcYhQLcTkf JqzA== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@nxp.com header.s=selector2 header.b=lUpFg15c; arc=pass (i=1 spf=pass spfdomain=nxp.com dkim=pass dkdomain=nxp.com dmarc=pass fromdomain=nxp.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nxp.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id s17-20020a632c11000000b0045ffa7279adsi17695241pgs.31.2022.10.19.05.06.27; Wed, 19 Oct 2022 05:06:42 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@nxp.com header.s=selector2 header.b=lUpFg15c; arc=pass (i=1 spf=pass spfdomain=nxp.com dkim=pass dkdomain=nxp.com dmarc=pass fromdomain=nxp.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nxp.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229871AbiJSMCb (ORCPT + 99 others); Wed, 19 Oct 2022 08:02:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231621AbiJSMBw (ORCPT ); Wed, 19 Oct 2022 08:01:52 -0400 Received: from EUR05-AM6-obe.outbound.protection.outlook.com (mail-am6eur05on2061.outbound.protection.outlook.com [40.107.22.61]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC9A313D45; Wed, 19 Oct 2022 04:38:40 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=LfM1ZDrxl7M7Ow+J08KrHgbiXwFC27AIvxt24ofVulrCZO0MJnv23reuzVMwhbKy0CKVMybf4+8NbbEeYU1U4iaW+zD7JiACpTyxXg+nk+7yattWnqF6h3jCSxDo+wH6QLIde4S56N/fN+E8+ZRapYDrJHrq4L+8dgQg7mtbw8rpYkeG7G99ZS83VK2t3Jhg97ap38eHmQlWTLil6CQbYYe0kOoCL9URXd5/UnKaSAl2L2XnxrolBNF2wMX3Un26k/jY5q76pzCw6RVdHoPJxNYHjJXi6I5Ldon0TqOClK543a04o7jGRRqSa9+nNssfnwuwP6m0e0QUz11oZB4NjQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=w0MHtjuLOB0x6YIhxA9jVBY4QB9MitIGbu0U4g813ZI=; b=NTJZWfCF6zKdzi9JZvcQXkyGBvxh87FH+gETsBNjvse+cOSWS113SzRp2wtbMLNavsBq/x312n/a9vuDT6wcj4T9xd9n2/0lTpgQiJS29AkvKsMrpFVBWqQjq7xMYEAkjYKV+666NkX2Y4IXFySzghDGfCRZSMHTOhOBq1pdf4CgnWHchrx45RUtLAQDLYKjixKYgCOCrX8QReeCYgMALA9IKyEpv86UjhCeJJHb9aNipLU9BNB9lekRJCS1/KTwJLhI8DliINZw5la8IGIEi93kRF+uo8CLPhVcSyfWbnnz8Ns6wUPWupIeB5yI76UvRnwo8gQ8U4XDDpYDjTQd1w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=w0MHtjuLOB0x6YIhxA9jVBY4QB9MitIGbu0U4g813ZI=; b=lUpFg15cQDvYg/dmkLvMb2qEWcppEpMcLhEPuqcPZoDnHcLZIgPmxRwgW7F4dTXOXx5tIbJ8dbeVIsS/2YF/AzcnuB3Ic3vQIYP+LJOkw6S/35nHyung4JNUlqeQyqF/eC2FVOYWcRDfwRodY3KqKnyUkJ2QEkZPhqj8dRo1rok= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from AS8PR04MB8404.eurprd04.prod.outlook.com (2603:10a6:20b:3f8::7) by VI1PR04MB6848.eurprd04.prod.outlook.com (2603:10a6:803:13c::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5723.26; Wed, 19 Oct 2022 11:09:51 +0000 Received: from AS8PR04MB8404.eurprd04.prod.outlook.com ([fe80::84cf:df3f:2012:79ea]) by AS8PR04MB8404.eurprd04.prod.outlook.com ([fe80::84cf:df3f:2012:79ea%5]) with mapi id 15.20.5723.033; Wed, 19 Oct 2022 11:09:51 +0000 From: Sherry Sun To: gregkh@linuxfoundation.org, jirislaby@kernel.org, lukas@wunner.de, ilpo.jarvinen@linux.intel.com Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-imx@nxp.com Subject: [PATCH V2] tty: serial: fsl_lpuart: don't break the on-going transfer when global reset Date: Wed, 19 Oct 2022 19:07:20 +0800 Message-Id: <20221019110720.31722-1-sherry.sun@nxp.com> X-Mailer: git-send-email 2.17.1 X-ClientProxiedBy: SI2PR02CA0047.apcprd02.prod.outlook.com (2603:1096:4:196::14) To AS8PR04MB8404.eurprd04.prod.outlook.com (2603:10a6:20b:3f8::7) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: AS8PR04MB8404:EE_|VI1PR04MB6848:EE_ X-MS-Office365-Filtering-Correlation-Id: e9418579-eefc-4e12-2bff-08dab1c2712a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:AS8PR04MB8404.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(4636009)(136003)(396003)(39860400002)(376002)(346002)(366004)(451199015)(8936002)(38350700002)(38100700002)(83380400001)(44832011)(5660300002)(41300700001)(4326008)(316002)(478600001)(1076003)(36756003)(66476007)(66946007)(66556008)(6666004)(52116002)(6512007)(2616005)(8676002)(26005)(6486002)(6506007)(186003)(2906002)(86362001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: e9418579-eefc-4e12-2bff-08dab1c2712a X-MS-Exchange-CrossTenant-AuthSource: AS8PR04MB8404.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Oct 2022 11:09:50.9676 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 3SZ5hMFjQYoGsEAVOWKxRA0a8GlLaE8vc02Pmt7YoFeFndTDJ8udd4qzNojubjUVESxoTvHhMtppOSeT2BhMYw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB6848 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1747098671351561786?= X-GMAIL-MSGID: =?utf-8?q?1747117620016942981?= lpuart_global_reset() shouldn't break the on-going transmit engin, need to recover the on-going data transfer after reset. This can help earlycon here, since commit 60f361722ad2 ("serial: fsl_lpuart: Reset prior to registration") moved lpuart_global_reset() before uart_add_one_port(), earlycon is writing during global reset, as global reset will disable the TX and clear the baud rate register, which caused the earlycon cannot work any more after reset, needs to restore the baud rate and re-enable the transmitter to recover the earlycon write. Fixes: bd5305dcabbc ("tty: serial: fsl_lpuart: do software reset for imx7ulp and imx8qxp") Signed-off-by: Sherry Sun --- Changes in V2: 1. The while loop may never exit as the stat and sfifo are not re-read inside the loop, fix that. --- drivers/tty/serial/fsl_lpuart.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 67fa113f77d4..9a0781395b1f 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -408,11 +408,9 @@ static int lpuart_global_reset(struct lpuart_port *sport) { struct uart_port *port = &sport->port; void __iomem *global_addr; + unsigned long tx_enable, bd; int ret; - if (uart_console(port)) - return 0; - ret = clk_prepare_enable(sport->ipg_clk); if (ret) { dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret); @@ -420,11 +418,29 @@ static int lpuart_global_reset(struct lpuart_port *sport) } if (is_imx7ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) { + /* + * If the transmitter is used by earlycon, wait transmit engin complete + * and then reset + */ + tx_enable = lpuart32_read(port, UARTCTRL) & UARTCTRL_TE; + if (tx_enable) { + bd = lpuart32_read(&sport->port, UARTBAUD); + while (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_TC && + lpuart32_read(port, UARTFIFO) & UARTFIFO_TXEMPT)) + cpu_relax(); + } + global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF; writel(UART_GLOBAL_RST, global_addr); usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US); writel(0, global_addr); usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US); + + /* Recover the transmitter for earlycon */ + if (tx_enable) { + lpuart32_write(port, bd, UARTBAUD); + lpuart32_write(port, UARTCTRL_TE, UARTCTRL); + } } clk_disable_unprepare(sport->ipg_clk);