From patchwork Thu Jun 19 10:38:11 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 4382311 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 93058BEEAA for ; Thu, 19 Jun 2014 10:42:24 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9CA772037F for ; Thu, 19 Jun 2014 10:42:23 +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 A47BB20384 for ; Thu, 19 Jun 2014 10:42:22 +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 1WxZkM-0002yR-Ui; Thu, 19 Jun 2014 10:39:10 +0000 Received: from mail-wi0-f173.google.com ([209.85.212.173]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WxZkK-0002t9-Mo for linux-arm-kernel@lists.infradead.org; Thu, 19 Jun 2014 10:39:09 +0000 Received: by mail-wi0-f173.google.com with SMTP id cc10so9112017wib.0 for ; Thu, 19 Jun 2014 03:38:47 -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=5h8bcY8RxkLefDBQzFjK5YIlyr5TbeZ+DgmM7F/ruG0=; b=XTnIC/tZkvirfsl3bqqNSD2Z0hvh7v8b08q9CmrxKG1KxlYlsTsBabor0q2Cn+n7V6 rtd7IW6QtruNIZujo0tOI/oxqqo/rJBSD576FJI9rXGUsS+sd+cpPSlq+Izc2Uva78fO FhyRgV67n46gWmNTu6wPY9GZsYekkaQAGt060x0YlZQUoQqrIhiIcbP8tgsRVuIUwIJW 9+pEY5k4G7hS30ZlJqVgbB6JRZsjVb7LLSO2UUWDDRjW3K0pMjMRckxFrO9BDdexZi7U T8mILZauniso4xYPuzVBfRxYcgqrS67+RNq9V0thjUvPoVIUfhrK5xJ3dCwINmYJNXDg iHJg== X-Gm-Message-State: ALoCoQmswGUn1zuYRe6Ec4bdxRqdLu89Xq685aXs6QMhuJMaE+Cz7IZAgYU9KUZTfU088bgOBj7m X-Received: by 10.180.83.131 with SMTP id q3mr5246643wiy.31.1403174327601; Thu, 19 Jun 2014 03:38:47 -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.29.2014.06.19.03.38.45 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 Jun 2014 03:38:46 -0700 (PDT) From: Daniel Thompson To: Jason Wessel Subject: [PATCH v4 01/13] arm: fiq: Add callbacks to manage FIQ routings Date: Thu, 19 Jun 2014 11:38:11 +0100 Message-Id: <1403174303-25456-2-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_033909_045707_1059C5DC X-CRM114-Status: GOOD ( 19.55 ) X-Spam-Score: -0.7 (/) Cc: Mark Rutland , kernel@stlinux.com, kgdb-bugreport@lists.sourceforge.net, Linus Walleij , Jiri Slaby , Daniel Thompson , Dirk Behme , Russell King , Nicolas Pitre , Fabio Estevam , 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, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Colin Cross , Frederic Weisbecker , Christoffer Dall 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 Currently enable_fiq/disable_fiq use a simple offset to convert an IRQ virq into a FIQ virq. This is too inflexible for multi-platform kernels and makes runtime error checking impossible. We solve this by introducing a flexible mapping that allows interrupt controllers that support FIQ to register those mappings. This, in turn, makes it much possible for drivers in DT kernels to install FIQ handlers without knowing anything about the interrupt controller. Signed-off-by: Daniel Thompson Cc: Russell King Cc: Fabio Estevam Cc: Nicolas Pitre --- arch/arm/include/asm/fiq.h | 7 +++ arch/arm/kernel/fiq.c | 103 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 108 insertions(+), 2 deletions(-) diff --git a/arch/arm/include/asm/fiq.h b/arch/arm/include/asm/fiq.h index d493d0b..a7806ef 100644 --- a/arch/arm/include/asm/fiq.h +++ b/arch/arm/include/asm/fiq.h @@ -18,6 +18,11 @@ #include +struct fiq_chip { + void (*fiq_enable)(struct irq_data *data); + void (*fiq_disable)(struct irq_data *data); +}; + struct fiq_handler { struct fiq_handler *next; /* Name @@ -38,6 +43,8 @@ extern void release_fiq(struct fiq_handler *f); extern void set_fiq_handler(void *start, unsigned int length); extern void enable_fiq(int fiq); extern void disable_fiq(int fiq); +extern bool has_fiq(int fiq); +extern void fiq_register_mapping(int irq, struct fiq_chip *chip); /* helpers defined in fiqasm.S: */ extern void __set_fiq_regs(unsigned long const *regs); diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c index 918875d..567f8fd 100644 --- a/arch/arm/kernel/fiq.c +++ b/arch/arm/kernel/fiq.c @@ -40,6 +40,9 @@ #include #include #include +#include +#include +#include #include #include @@ -52,7 +55,15 @@ (unsigned)&vector_fiq_offset; \ }) +struct fiq_data { + struct fiq_chip *fiq_chip; + struct irq_data *irq_data; +}; + static unsigned long no_fiq_insn; +static int fiq_start = -1; +static RADIX_TREE(fiq_data_tree, GFP_KERNEL); +static DEFINE_MUTEX(fiq_data_mutex); /* Default reacquire function * - we always relinquish FIQ control @@ -127,18 +138,65 @@ void release_fiq(struct fiq_handler *f) while (current_fiq->fiq_op(current_fiq->dev_id, 0)); } -static int fiq_start; +static struct fiq_data *lookup_fiq_data(int fiq) +{ + struct fiq_data *data; + + rcu_read_lock(); + data = radix_tree_lookup(&fiq_data_tree, fiq); + rcu_read_unlock(); + + return data; +} void enable_fiq(int fiq) { + struct fiq_data *data = lookup_fiq_data(fiq); + + if (data) { + if (data->fiq_chip->fiq_enable) + data->fiq_chip->fiq_enable(data->irq_data); + enable_irq(fiq); + return; + } + + if (WARN_ON(fiq_start == -1)) + return; + enable_irq(fiq + fiq_start); } void disable_fiq(int fiq) { + struct fiq_data *data = lookup_fiq_data(fiq); + + if (data) { + if (data->fiq_chip->fiq_disable) + data->fiq_chip->fiq_disable(data->irq_data); + disable_irq(fiq); + return; + } + + if (WARN_ON(fiq_start == -1)) + return; + disable_irq(fiq + fiq_start); } +bool has_fiq(int fiq) +{ + struct fiq_data *data = lookup_fiq_data(fiq); + + if (data) + return true; + + if (fiq_start == -1) + return false; + + return fiq > fiq_start; +} +EXPORT_SYMBOL(has_fiq); + EXPORT_SYMBOL(set_fiq_handler); EXPORT_SYMBOL(__set_fiq_regs); /* defined in fiqasm.S */ EXPORT_SYMBOL(__get_fiq_regs); /* defined in fiqasm.S */ @@ -147,9 +205,50 @@ EXPORT_SYMBOL(release_fiq); EXPORT_SYMBOL(enable_fiq); EXPORT_SYMBOL(disable_fiq); +/* + * Add a mapping from a Linux irq to the fiq data. + */ +void fiq_register_mapping(int irq, struct fiq_chip *chip) +{ + struct fiq_data *fiq_data = NULL; + int res; + + /* fiq_register_mapping can't be mixed with init_FIQ */ + BUG_ON(fiq_start != -1); + + fiq_data = kmalloc(sizeof(*fiq_data), GFP_KERNEL); + if (!fiq_data) + goto err; + + fiq_data->fiq_chip = chip; + fiq_data->irq_data = irq_get_irq_data(irq); + BUG_ON(!fiq_data->irq_data); + + mutex_lock(&fiq_data_mutex); + res = radix_tree_insert(&fiq_data_tree, irq, fiq_data); + mutex_unlock(&fiq_data_mutex); + if (res) + goto err; + + return; + +err: + kfree(fiq_data); + pr_err("fiq: Cannot register mapping %d\n", irq); +} + +/* + * Set the offset between normal IRQs and their FIQ shadows. + */ void __init init_FIQ(int start) { + fiq_start = start; +} + +static int __init init_default_fiq_handler(void) +{ unsigned offset = FIQ_OFFSET; no_fiq_insn = *(unsigned long *)(0xffff0000 + offset); - fiq_start = start; + return 0; } +pure_initcall(init_default_fiq_handler);