From patchwork Thu Jun 19 10:38:20 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 4382381 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 6EABB9F26E for ; Thu, 19 Jun 2014 10:46:37 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8A3CB20384 for ; Thu, 19 Jun 2014 10:46:36 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8B5422037F for ; Thu, 19 Jun 2014 10:46:35 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WxZp8-0006VM-NJ; Thu, 19 Jun 2014 10:44:06 +0000 Received: from mail-we0-f173.google.com ([74.125.82.173]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WxZkf-0002xN-1s for linux-arm-kernel@lists.infradead.org; Thu, 19 Jun 2014 10:39:30 +0000 Received: by mail-we0-f173.google.com with SMTP id t60so2129812wes.18 for ; Thu, 19 Jun 2014 03:39:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=ABwj1of6LeLUU0Tt1ZNHYT9yoja0lSF4+thrq8/oTwY=; b=hN2flXk+sklw/Pdka7Yle7NgezRRuVQmskeRStf0ok3VneEb03r2WW4ZeUGbwJW3c9 n0FzLkYG3TC0oKF05er383AVTGPEu41pJt1N5bFJdkb2sd3dwEDHLSCgXNZXAjqAoHMz yd47iWVvbD+JeWccUR2qMwNFp7J/j3IUhAhevXedPMvNwHFSd3xhvCriHrKrlPXdEeDT 23po1XleLk8R8zlx6URcJCnry+Qmcj1MD7ZVKI0yERSdhF6KtXDruqbEHS2M4BDk9SmS L+uFTjQB4fTOLvgT00M+pTgxo1Jctl+svhmJfnMKdwiUTA2/wT0gKnheM9H/cpGXZeyT JylQ== X-Gm-Message-State: ALoCoQl3QDPZpuMNWgv1QeuMJi+M6LDyckQCKjtxt4+CW8Mwk6j88Cl2V5fiiC96p1Wvi+GTP3dv X-Received: by 10.180.212.77 with SMTP id ni13mr5176983wic.5.1403174346908; Thu, 19 Jun 2014 03:39:06 -0700 (PDT) Received: from sundance.lan (cpc4-aztw19-0-0-cust157.18-1.cable.virginm.net. [82.33.25.158]) by mx.google.com with ESMTPSA id hi2sm7881147wjb.29.2014.06.19.03.39.04 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 Jun 2014 03:39:06 -0700 (PDT) From: Daniel Thompson To: Jason Wessel Subject: [PATCH v4 10/13] serial: asc: Add support for KGDB's FIQ/NMI mode Date: Thu, 19 Jun 2014 11:38:20 +0100 Message-Id: <1403174303-25456-11-git-send-email-daniel.thompson@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1403174303-25456-1-git-send-email-daniel.thompson@linaro.org> References: <1401961994-18033-1-git-send-email-daniel.thompson@linaro.org> <1403174303-25456-1-git-send-email-daniel.thompson@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140619_033929_262393_6D62C3D7 X-CRM114-Status: GOOD ( 16.34 ) X-Spam-Score: -0.7 (/) Cc: Mark Rutland , kernel@stlinux.com, kgdb-bugreport@lists.sourceforge.net, Linus Walleij , Patrice Chotard , Jiri Slaby , Daniel Thompson , Dirk Behme , Russell King , Nicolas Pitre , Ian Campbell , Anton Vorontsov , "David A. Long" , linux-serial@vger.kernel.org, Catalin Marinas , kernel-team@android.com, devicetree@vger.kernel.org, linaro-kernel@lists.linaro.org, Pawel Moll , patches@linaro.org, Kumar Gala , Rob Herring , John Stultz , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Maxime Coquelin , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Colin Cross , Frederic Weisbecker , Christoffer Dall , Srinivas Kandagatla X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add a .poll_init() function that enables UART RX and registers the UART's irq with KGDB. By providing this information to KGDB the serial driver offers "permission" for KGDB to route the UART interrupt signal from the drivers own handler to KGDBs FIQ handler (which will eventually use the UART's polled I/O callbacks to interact with the user). Note that the RX is not only enabled but also unmasked. This is required because otherwise the FIQ handler could never trigger. This unmask is copied from similar code in amba-pl011.c . Signed-off-by: Daniel Thompson Cc: Srinivas Kandagatla Cc: Maxime Coquelin Cc: Patrice Chotard Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: kernel@stlinux.com Cc: linux-serial@vger.kernel.org Acked-by: Greg Kroah-Hartman --- drivers/tty/serial/st-asc.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c index c7f61ac..4f376d8 100644 --- a/drivers/tty/serial/st-asc.c +++ b/drivers/tty/serial/st-asc.c @@ -30,6 +30,7 @@ #include #include #include +#include #define DRIVER_NAME "st-asc" #define ASC_SERIAL_NAME "ttyAS" @@ -613,6 +614,25 @@ asc_verify_port(struct uart_port *port, struct serial_struct *ser) } #ifdef CONFIG_CONSOLE_POLL + +#ifdef CONFIG_KGDB_FIQ +/* + * Prepare the UART to be used from kgdb's NMI support. + */ +static int asc_poll_init(struct uart_port *port) +{ + struct asc_port *ascport = container_of(port, struct asc_port, port); + + /* register the FIQ with kgdb */ + kgdb_register_fiq(ascport->port.irq); + + /* enable RX interrupts in case the interrupt is used for NMI entry. */ + asc_enable_rx_interrupts(port); + + return 0; +} +#endif /* CONFIG_KGDB_FIQ */ + /* * Console polling routines for writing and reading from the uart while * in an interrupt or debug context (i.e. kgdb). @@ -656,6 +676,9 @@ static struct uart_ops asc_uart_ops = { .verify_port = asc_verify_port, .pm = asc_pm, #ifdef CONFIG_CONSOLE_POLL +#ifdef CONFIG_KGDB_FIQ + .poll_init = asc_poll_init, +#endif /* CONFIG_KGDB_FIQ */ .poll_get_char = asc_get_poll_char, .poll_put_char = asc_put_poll_char, #endif /* CONFIG_CONSOLE_POLL */