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=-13.8 required=3.0 tests=BAYES_00, DATE_IN_FUTURE_06_12,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 280E8C64E7A for ; Tue, 1 Dec 2020 15:06:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6B251206C1 for ; Tue, 1 Dec 2020 15:06:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="k/8xOGCS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391617AbgLAPGI (ORCPT ); Tue, 1 Dec 2020 10:06:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388658AbgLAPGH (ORCPT ); Tue, 1 Dec 2020 10:06:07 -0500 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A82AC0613CF for ; Tue, 1 Dec 2020 07:05:27 -0800 (PST) Received: by mail-pf1-x441.google.com with SMTP id q10so1301924pfn.0 for ; Tue, 01 Dec 2020 07:05:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1eU7j8BPKnWBddO7CUJ6gQsdoCuU7j9gjTF1r55fd6o=; b=k/8xOGCSHs/NFP97H7XObBKaRl6q82qCkUHmcGoRygKALd0V5qtgAouHqEXXVabRpv F9jnD6t8COEzc8yVaoAsj+5KUcqC78uhIlVVpIQuOg6X5cV7+wWPz8acnRgX44Y/MuKE Dk6CM3PgT2hGJeIo8CiVqix954FJZ7rZvscrTfgWU2pnAWGiq7InCVHK80R65tb+F5AS HPUG9TYPoCkqlhyd1rEiKorX02cwzZs46w2376wKSXHCYzyJsnivp9dVDHG6ItaiiPuR wBVmGeBogdc1UxRqZFn7tL/ETIHAJ2pSKDMU54jw72xuhP7aJKXSdvRk6bnRYJQP8WWP nZuw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1eU7j8BPKnWBddO7CUJ6gQsdoCuU7j9gjTF1r55fd6o=; b=YMp4DuhyTdsrIAMmbDX86Yq1f+UH7OMLFv5I8q3iW90JRzL3f2svyAwHsVAYns9Ldy tU5OX3QBSXubUQ9IHeFuZ/qW2baJ9rG7FsDDllRXSTAASNW/3qa0AQWruwjAhlCcP/H9 cdd01zhsngrYbPQ8tsPPMHNhYRP2yJrAPVXBPEBia79Gosa9YCjkkiedAZTzUD4XE7Av RPdlJQf3byJ44GEESE8s8W+abhwOnHXPrFc+bUNfwnSgsEv0HjZIk/u6f7j1bqFe/ooY AgmiHGgkPraFUek33neH/ptcPdubPw6dKlFPh2nQBW+G+wplk3q39KPGr8+zPNFeohGs btDw== X-Gm-Message-State: AOAM530UuLrqlnNd2jW9xbp7YrJP2JozAo09/MGfnzjnZyEsFDQQ5XUK ld5j5d5KKyNFLjp65uL7w68= X-Google-Smtp-Source: ABdhPJwKw7peE+tmHZS5R+XJqXJKC7j/LcI8voG1JvHkG1HmXeNsE/3SPB9NPpGJFmXIrhJLP3Sh+g== X-Received: by 2002:a63:df05:: with SMTP id u5mr2584816pgg.73.1606835126601; Tue, 01 Dec 2020 07:05:26 -0800 (PST) Received: from localhost.localdomain ([103.149.248.59]) by smtp.gmail.com with ESMTPSA id q6sm57677pfu.23.2020.12.01.07.05.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Dec 2020 07:05:26 -0800 (PST) From: jiladahe1997 X-Google-Original-From: jiladahe1997 <972931182@qq.com> To: gregkh@linuxfoundation.org, shawnguo@kernel.org, s.hauer@pengutronix.de Cc: linux-imx@nxp.com, linux-kernel@vger.kernel.org, 972931182@qq.com, Mingrui Ren Subject: [PATCH RESEND] tty/serial/imx: Enable TXEN bit in imx_poll_init(). Date: Wed, 2 Dec 2020 07:03:08 +0800 Message-Id: <20201201230307.5738-1-972931182@qq.com> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mingrui Ren As described in Documentation, poll_init() is called by kgdb to initialize hardware which supports both poll_put_char() and poll_get_char(). It's necessary to enable TXEN bit, otherwise, it will cause hardware fault and kernel panic when calling imx_poll_put_char(). Generally, if use /dev/ttymxc0 as kgdb console as well as system console, ttymxc0 is initialized early by system console which does enable TXEN bit.But when use /dev/ttymxc1 as kgbd console, ttymxc1 is only initialized by imx_poll_init() cannot enable the TXEN bit, which will cause kernel panic. Signed-off-by: Mingrui Ren --- Hi, thanks for your reply, and sorry for sending two identical emails. The email service I used before seems to have some problems, so I switched to gmail.This is the "correct" version, please check. drivers/tty/serial/imx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 43c6d7142fdd..7c665db3d897 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1829,7 +1829,7 @@ static int imx_uart_poll_init(struct uart_port *port) ucr1 |= UCR1_UARTEN; ucr1 &= ~(UCR1_TRDYEN | UCR1_RTSDEN | UCR1_RRDYEN); - ucr2 |= UCR2_RXEN; + ucr2 |= UCR2_RXEN|UCR2_TXEN; ucr2 &= ~UCR2_ATEN; imx_uart_writel(sport, ucr1, UCR1); -- 2.29.2