From patchwork Mon Aug 18 14:12:54 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 35503 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-ob0-f199.google.com (mail-ob0-f199.google.com [209.85.214.199]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 1738320523 for ; Mon, 18 Aug 2014 14:13:16 +0000 (UTC) Received: by mail-ob0-f199.google.com with SMTP id wn1sf35972050obc.2 for ; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:x-original-sender :x-original-authentication-results:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-unsubscribe; bh=KHwUZqXCggmg6InxKDyZXGQdEb0a6jwKgUU+J7920BA=; b=NduBZ0NrPouzid1fkA9T5T/qQzofZ3fAr7TYrDkN5Yk3hgOu8DasSFqVMaKdH+5YFW IsYG/Oj7d1evV97OCY2U1Zy0X3UQjF2eO6bi1LEeWTpTyfyIh4pItG9Tz4udEGP+dxs5 fXaEeoY+zV5pO/rqTnB8iIMUX5JHwsgt8zMikJ+VVID8Hlg0ApEnjApLodoR1tt6Fy8Y kil5lGIZCa6/WsLmEGjZ4mC5Ynb3EwTYtRVQr7SXxsgelaDMI3Ab9NFhULRbOolV72Sa wVDcks7BMC4+F7Y0DRANlKbRmXwOU7JCW8qDSwe3M2LP++pSJMHV3HrNwdn+MiegUR9z VLsw== X-Gm-Message-State: ALoCoQlud+7+0FHraMLhu93kJ4JU0pSPBZA4NPfnSJVtmMCbnNOmFPj0Aq6SHUEq0oUzwJsz5Vjy X-Received: by 10.42.225.77 with SMTP id ir13mr19523422icb.3.1408371195655; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.140.92.102 with SMTP id a93ls2316408qge.15.gmail; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) X-Received: by 10.52.249.66 with SMTP id ys2mr1468973vdc.41.1408371195417; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) Received: from mail-vc0-f173.google.com (mail-vc0-f173.google.com [209.85.220.173]) by mx.google.com with ESMTPS id fc5si5521056vec.99.2014.08.18.07.13.15 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 18 Aug 2014 07:13:15 -0700 (PDT) Received-SPF: pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.220.173 as permitted sender) client-ip=209.85.220.173; Received: by mail-vc0-f173.google.com with SMTP id hy10so5807672vcb.18 for ; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) X-Received: by 10.52.3.40 with SMTP id 8mr1158603vdz.24.1408371195307; Mon, 18 Aug 2014 07:13:15 -0700 (PDT) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patches@linaro.org Received: by 10.221.37.5 with SMTP id tc5csp155650vcb; Mon, 18 Aug 2014 07:13:14 -0700 (PDT) X-Received: by 10.180.87.231 with SMTP id bb7mr42472296wib.63.1408371194007; Mon, 18 Aug 2014 07:13:14 -0700 (PDT) Received: from mail-wi0-f176.google.com (mail-wi0-f176.google.com [209.85.212.176]) by mx.google.com with ESMTPS id l1si17019358wij.59.2014.08.18.07.13.13 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 18 Aug 2014 07:13:13 -0700 (PDT) Received-SPF: pass (google.com: domain of daniel.thompson@linaro.org designates 209.85.212.176 as permitted sender) client-ip=209.85.212.176; Received: by mail-wi0-f176.google.com with SMTP id bs8so3783355wib.15 for ; Mon, 18 Aug 2014 07:13:13 -0700 (PDT) X-Received: by 10.180.19.97 with SMTP id d1mr42093300wie.19.1408371193473; Mon, 18 Aug 2014 07:13:13 -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 pe6sm42575328wjb.38.2014.08.18.07.13.11 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 18 Aug 2014 07:13:12 -0700 (PDT) From: Daniel Thompson To: Russell King Cc: Daniel Thompson , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kgdb-bugreport@lists.sourceforge.net, patches@linaro.org, linaro-kernel@lists.linaro.org, John Stultz , Anton Vorontsov , Colin Cross , kernel-team@android.com, Rob Herring , Linus Walleij , Ben Dooks , Catalin Marinas , Dave Martin , Fabio Estevam , Frederic Weisbecker , Nicolas Pitre , Thomas Gleixner , Jason Cooper , Nicolas Pitre , Christoffer Dall , Sricharan R , Marc Zyngier Subject: [PATCH v9 06/16] irqchip: gic: Provide support for interrupt grouping Date: Mon, 18 Aug 2014 15:12:54 +0100 Message-Id: <1408371184-12576-7-git-send-email-daniel.thompson@linaro.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1404979427-12943-1-git-send-email-daniel.thompson@linaro.org> References: <1404979427-12943-1-git-send-email-daniel.thompson@linaro.org> X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: daniel.thompson@linaro.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 209.85.220.173 as permitted sender) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Precedence: list Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org List-ID: X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , All GIC hardware except GICv1-without-TrustZone support provides a means to group exceptions into group 0 (which can optionally be signally using use FIQ) and group 1. The kernel currently provides no means to exploit this. This patch alters the initialization of the GIC to place all interrupts into group 1 which is the foundational requirement to meaningfully use FIQ. Note that the hardware functionality is unavailable to the kernel when a secure monitor is present because access to the grouping registers are prohibited outside "secure world" (this feature allows grouping to be used to allow hardware peripherals to send interrupts into the secure world). The GIC driver will automatically detect this and disable its attempts to group interrupts. On systems without TrustZone support the kernel has the power to route interrupt sources to FIQ, potentially allowing a driver to exploit the NMI-like properties of FIQ. Tested on Freescale i.MX6 (quad A9), STiH416 (dual A9) and a self-written qemu GICv2 model. Signed-off-by: Daniel Thompson Cc: Thomas Gleixner Cc: Jason Cooper Cc: Nicolas Pitre Cc: Christoffer Dall Cc: Sricharan R Cc: Marc Zyngier Acked-by: Dirk Behme --- drivers/irqchip/irq-gic.c | 99 ++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 94 insertions(+), 5 deletions(-) diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c index 4b959e6..423707c 100644 --- a/drivers/irqchip/irq-gic.c +++ b/drivers/irqchip/irq-gic.c @@ -41,6 +41,9 @@ #include #include +#ifdef CONFIG_FIQ +#include +#endif #include #include #include @@ -68,6 +71,9 @@ struct gic_chip_data { #ifdef CONFIG_GIC_NON_BANKED void __iomem *(*get_base)(union gic_base *); #endif +#ifdef CONFIG_FIQ + bool fiq_enable; +#endif }; static DEFINE_RAW_SPINLOCK(irq_controller_lock); @@ -131,6 +137,16 @@ static inline void gic_set_base_accessor(struct gic_chip_data *data, #define gic_set_base_accessor(d, f) #endif +#ifdef CONFIG_FIQ +static inline bool gic_data_fiq_enable(struct gic_chip_data *data) +{ + return data->fiq_enable; +} +#else +static inline bool gic_data_fiq_enable( + struct gic_chip_data *data) { return false; } +#endif + static inline void __iomem *gic_dist_base(struct irq_data *d) { struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d); @@ -325,6 +341,42 @@ static struct irq_chip gic_chip = { .irq_set_wake = gic_set_wake, }; +#ifdef CONFIG_FIQ +static void __init gic_init_fiq(struct gic_chip_data *gic, + irq_hw_number_t first_irq, + unsigned int num_irqs) +{ + void __iomem *dist_base = gic_data_dist_base(gic_data); + unsigned int i; + + /* + * FIQ can only be supported on platforms without an extended irq_eoi + * method (otherwise we take a lock during eoi handling). + */ + if (gic_arch_extn.irq_eoi) + return; + + /* + * If grouping is not available (not implemented or prohibited by + * security mode) these registers a read-as-zero/write-ignored. + * However as a precaution we restore the reset default regardless of + * the result of the test. + */ + writel_relaxed(1, dist_base + GIC_DIST_IGROUP + 0); + gic->fiq_enable = readl_relaxed(dist_base + GIC_DIST_IGROUP + 0); + writel_relaxed(0, dist_base + GIC_DIST_IGROUP + 0); + pr_debug("gic: FIQ support %s\n", + gic->fiq_enable ? "enabled" : "disabled"); + + if (!gic->fiq_enable) + return; +} +#else /* CONFIG_FIQ */ +static inline void gic_init_fiq(struct gic_chip_data *gic, + irq_hw_number_t first_irq, + unsigned int num_irqs) {} +#endif /* CONFIG_FIQ */ + void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq) { if (gic_nr >= MAX_GIC_NR) @@ -373,7 +425,22 @@ static void __init gic_dist_init(struct gic_chip_data *gic) gic_dist_config(base, gic_irqs, NULL); - writel_relaxed(1, base + GIC_DIST_CTRL); + /* + * Optionally set all global interrupts to be group 1. + */ + if (gic_data_fiq_enable(gic)) + for (i = 32; i < gic_irqs; i += 32) + writel_relaxed(0xffffffff, + base + GIC_DIST_IGROUP + i * 4 / 32); + + /* + * Set EnableGrp1/EnableGrp0 (bit 1 and 0) or EnableGrp (bit 0 only, + * bit 1 ignored) + */ + if (gic_data_fiq_enable(gic)) + writel_relaxed(3, base + GIC_DIST_CTRL); + else + writel_relaxed(1, base + GIC_DIST_CTRL); } static void gic_cpu_init(struct gic_chip_data *gic) @@ -400,8 +467,20 @@ static void gic_cpu_init(struct gic_chip_data *gic) gic_cpu_config(dist_base, NULL); + /* + * Set all PPI and SGI interrupts to be group 1. + * + * If grouping is not available (not implemented or prohibited by + * security mode) these registers are read-as-zero/write-ignored. + */ + if (gic_data_fiq_enable(gic)) + writel_relaxed(0xffffffff, dist_base + GIC_DIST_IGROUP + 0); + writel_relaxed(0xf0, base + GIC_CPU_PRIMASK); - writel_relaxed(1, base + GIC_CPU_CTRL); + if (gic_data_fiq_enable(gic)) + writel_relaxed(0x1f, base + GIC_CPU_CTRL); + else + writel_relaxed(1, base + GIC_CPU_CTRL); } void gic_cpu_if_down(void) @@ -485,7 +564,10 @@ static void gic_dist_restore(unsigned int gic_nr) writel_relaxed(gic_data[gic_nr].saved_spi_enable[i], dist_base + GIC_DIST_ENABLE_SET + i * 4); - writel_relaxed(1, dist_base + GIC_DIST_CTRL); + if (gic_data_fiq_enable(&gic_data[gic_nr])) + writel_relaxed(3, dist_base + GIC_DIST_CTRL); + else + writel_relaxed(1, dist_base + GIC_DIST_CTRL); } static void gic_cpu_save(unsigned int gic_nr) @@ -542,7 +624,7 @@ static void gic_cpu_restore(unsigned int gic_nr) writel_relaxed(0xa0a0a0a0, dist_base + GIC_DIST_PRI + i * 4); writel_relaxed(0xf0, cpu_base + GIC_CPU_PRIMASK); - writel_relaxed(1, cpu_base + GIC_CPU_CTRL); + writel_relaxed(0x1f, cpu_base + GIC_CPU_CTRL); } static int gic_notifier(struct notifier_block *self, unsigned long cmd, void *v) @@ -604,6 +686,7 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) { int cpu; unsigned long flags, map = 0; + unsigned long softint; raw_spin_lock_irqsave(&irq_controller_lock, flags); @@ -618,7 +701,11 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq) dmb(ishst); /* this always happens on GIC0 */ - writel_relaxed(map << 16 | irq, gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT); + softint = map << 16 | irq; + if (gic_data_fiq_enable(&gic_data[0])) + softint |= 0x8000; + writel_relaxed(softint, + gic_data_dist_base(&gic_data[0]) + GIC_DIST_SOFTINT); raw_spin_unlock_irqrestore(&irq_controller_lock, flags); } @@ -964,6 +1051,8 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start, gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base, hwirq_base, &gic_irq_domain_ops, gic); + + gic_init_fiq(gic, irq_base, gic_irqs); } else { gic->domain = irq_domain_add_linear(node, nr_routable_irqs, &gic_irq_domain_ops,