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 9AE31C32772 for ; Tue, 23 Aug 2022 11:28:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240409AbiHWL2l (ORCPT ); Tue, 23 Aug 2022 07:28:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243725AbiHWLWk (ORCPT ); Tue, 23 Aug 2022 07:22:40 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB69B37FB8; Tue, 23 Aug 2022 02:23:30 -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 ams.source.kernel.org (Postfix) with ESMTPS id F1CDDB81C66; Tue, 23 Aug 2022 09:18:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49539C433D6; Tue, 23 Aug 2022 09:18:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661246303; bh=R4C2c3WFFmkYTu566XNSyyK3NoFMApqQVZetXM93FfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BMB0elDSirvuOPkEOhBXR9ZZWygm1EG4h3s5ZY95479+7d3l2k4tesZ1yRteYH6mJ 0F9C12xowdurRIYmnzdkxkXyhP2RKHCSoC0qv5h38Yyc0YYQDjZun2PzKhwdSKaD4k 0YfHxo0jzODQqGkqPrvRzI8QWLIB+K2sXb2StYUk= 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 5.4 036/389] serial: mvebu-uart: uart2 error bits clearing Date: Tue, 23 Aug 2022 10:21:54 +0200 Message-Id: <20220823080117.160262496@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080115.331990024@linuxfoundation.org> References: <20220823080115.331990024@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);