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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A79CC32792 for ; Fri, 19 Aug 2022 15:56:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350531AbiHSP4i (ORCPT ); Fri, 19 Aug 2022 11:56:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350532AbiHSPys (ORCPT ); Fri, 19 Aug 2022 11:54:48 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 238FC10474D; Fri, 19 Aug 2022 08:49:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 23F106171C; Fri, 19 Aug 2022 15:49:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 278DAC433D6; Fri, 19 Aug 2022 15:49:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660924181; bh=R4C2c3WFFmkYTu566XNSyyK3NoFMApqQVZetXM93FfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wMrKWYODXQtPugdUt1Bb7Lbr5sJ1atBfkqzGLGBs+PyiYfTfmJCvSAS6Fts+gyGWi 5zyi9oyfhoUL7yUCcBrVGP7oMUMfxCePImCAUQS5hzwkiYb5ITneQ9Mt3cZumRZAxl h9Mzlb5lW9WHcrCoWi+MF0ASjzeCzJvNW4V2DcZA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yi Guo , Nadav Haklai , Narendra Hadke , =?UTF-8?q?Pali=20Roh=C3=A1r?= Subject: [PATCH 5.10 054/545] serial: mvebu-uart: uart2 error bits clearing Date: Fri, 19 Aug 2022 17:37:04 +0200 Message-Id: <20220819153831.643984737@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220819153829.135562864@linuxfoundation.org> References: <20220819153829.135562864@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Narendra Hadke commit a7209541239e5dd44d981289e5f9059222d40fd1 upstream. For mvebu uart2, error bits are not cleared on buffer read. This causes interrupt loop and system hang. Cc: stable@vger.kernel.org Reviewed-by: Yi Guo Reviewed-by: Nadav Haklai Signed-off-by: Narendra Hadke Signed-off-by: Pali Rohár Link: https://lore.kernel.org/r/20220726091221.12358-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mvebu-uart.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -238,6 +238,7 @@ static void mvebu_uart_rx_chars(struct u struct tty_port *tport = &port->state->port; unsigned char ch = 0; char flag = 0; + int ret; do { if (status & STAT_RX_RDY(port)) { @@ -250,6 +251,16 @@ static void mvebu_uart_rx_chars(struct u port->icount.parity++; } + /* + * For UART2, error bits are not cleared on buffer read. + * This causes interrupt loop and system hang. + */ + if (IS_EXTENDED(port) && (status & STAT_BRK_ERR)) { + ret = readl(port->membase + UART_STAT); + ret |= STAT_BRK_ERR; + writel(ret, port->membase + UART_STAT); + } + if (status & STAT_BRK_DET) { port->icount.brk++; status &= ~(STAT_FRM_ERR | STAT_PAR_ERR);