From patchwork Thu Sep 4 16:03:36 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 4846911 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id D97BAC0338 for ; Thu, 4 Sep 2014 16:08:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9ABA82026D for ; Thu, 4 Sep 2014 16:08:38 +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 31BA220274 for ; Thu, 4 Sep 2014 16:08:37 +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 1XPZWo-000083-25; Thu, 04 Sep 2014 16:04:54 +0000 Received: from mail-wi0-f180.google.com ([209.85.212.180]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XPZWI-0008AE-W1 for linux-arm-kernel@lists.infradead.org; Thu, 04 Sep 2014 16:04:23 +0000 Received: by mail-wi0-f180.google.com with SMTP id ex7so1388875wid.13 for ; Thu, 04 Sep 2014 09:03:58 -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=TVBO9JYaTweA2ueM1yzJjI/EduyubcNNdhgk78moBPc=; b=ifCR99wUvwTCfFMAI63wXtMNS1ylWtWzR+Bhc+pVcuqa9xoeRnPndDk+opuOBeznHe TEn4BQGypdLszOpUXhqJxrrgkxaLtHbisYVs/AGctqt9M/BjG/QMqTw2EjZYBvlKQIRu Q7x4xFRuwTNgCApAsNgUF17cF1b84FiWJpuVOPCPy5WMSeQRIodytt/PRffnAIuCizyB mlvPHsk98Kv8Ux7Pz7yJofiOGSAjc10+25kK2NPsneVxhoVhYuPI8uf3ioQMxlrM0Cb7 AAU/ntVwwXwtDWJmRar9/BizkT3k3oD/RxOaRPBMw36ZGB0HYC121RPOQwr6IpbiP6G4 1RLg== X-Gm-Message-State: ALoCoQkZKbheurlxiAp+xQpwPZJ28s94EDwTQBAzcXusguFLhiU3MsE6IUNMVGZ4qZJk7yK24pIf X-Received: by 10.180.20.148 with SMTP id n20mr7174760wie.22.1409846637557; Thu, 04 Sep 2014 09:03:57 -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 m9sm19841199wjz.35.2014.09.04.09.03.56 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 04 Sep 2014 09:03:56 -0700 (PDT) From: Daniel Thompson To: Russell King Subject: [PATCH v1 2/6] arm: smp: Introduce a non-maskable IPI Date: Thu, 4 Sep 2014 17:03:36 +0100 Message-Id: <1409846620-14542-3-git-send-email-daniel.thompson@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1409846620-14542-1-git-send-email-daniel.thompson@linaro.org> References: <1409662853-29313-1-git-send-email-daniel.thompson@linaro.org> <1409846620-14542-1-git-send-email-daniel.thompson@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140904_090423_216280_47734E29 X-CRM114-Status: GOOD ( 13.03 ) X-Spam-Score: -0.7 (/) Cc: Daniel Thompson , linaro-kernel@lists.linaro.org, patches@linaro.org, linux-kernel@vger.kernel.org, John Stultz , Thomas Gleixner , Sumit Semwal , linux-arm-kernel@lists.infradead.org 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=-3.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, 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 This patch introduces a new IPI intended to be routed to FIQ rather than IRQ. An IPI based upon FIQ can be used to implement debug features that require non-maskable interrupts. Signed-off-by: Daniel Thompson Cc: Russell King --- arch/arm/include/asm/hardirq.h | 2 +- arch/arm/include/asm/smp.h | 3 +++ arch/arm/kernel/smp.c | 7 +++++++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm/include/asm/hardirq.h b/arch/arm/include/asm/hardirq.h index fe3ea77..5df33e3 100644 --- a/arch/arm/include/asm/hardirq.h +++ b/arch/arm/include/asm/hardirq.h @@ -5,7 +5,7 @@ #include #include -#define NR_IPI 8 +#define NR_IPI 9 typedef struct { unsigned int __softirq_pending; diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h index 2ec765c..0e23384 100644 --- a/arch/arm/include/asm/smp.h +++ b/arch/arm/include/asm/smp.h @@ -20,6 +20,9 @@ #define raw_smp_processor_id() (current_thread_info()->cpu) +/* bitmap of IPIs that must be signalled using FIQ */ +#define SMP_IPI_FIQ_MASK 0x0100 + struct seq_file; /* diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 9388a3d..b2404d0 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -72,6 +72,7 @@ enum ipi_msg_type { IPI_CPU_STOP, IPI_IRQ_WORK, IPI_COMPLETION, + IPI_FIQ, }; static DECLARE_COMPLETION(cpu_running); @@ -451,6 +452,7 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = { S(IPI_CPU_STOP, "CPU stop interrupts"), S(IPI_IRQ_WORK, "IRQ work interrupts"), S(IPI_COMPLETION, "completion interrupts"), + S(IPI_FIQ, "FIQ interrupts"), }; static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) @@ -618,6 +620,11 @@ void handle_IPI(int ipinr, struct pt_regs *regs) irq_exit(); break; + case IPI_FIQ: + BUILD_BUG_ON(SMP_IPI_FIQ_MASK != BIT(IPI_FIQ)); + pr_warn("CPU%u: IPI FIQ delivered via IRQ vector\n", cpu); + break; + default: printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);