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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 061B9C43381 for ; Sat, 2 Mar 2019 04:30:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BEC4520857 for ; Sat, 2 Mar 2019 04:30:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=sholland.org header.i=@sholland.org header.b="KMKWYtgM"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="GSsxn+p9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726412AbfCBEaK (ORCPT ); Fri, 1 Mar 2019 23:30:10 -0500 Received: from out2-smtp.messagingengine.com ([66.111.4.26]:54715 "EHLO out2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728087AbfCBEaB (ORCPT ); Fri, 1 Mar 2019 23:30:01 -0500 Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id E49F62212C; Fri, 1 Mar 2019 23:29:59 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute5.internal (MEProxy); Fri, 01 Mar 2019 23:29:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sholland.org; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; s=fm2; bh=fXphOE/P/aA++ clgr5KBMvTn+12qMc94HBZ4q+3txlY=; b=KMKWYtgMNkxfKU9H/lGHeEnKbjruS dvDgbYlMlQW44Grw+z4fckki7J4UZ32ox9/WsTNZRkuTQprcS9CedhfGIJ83yOM4 7HvvGprPpxVRHXOnnms1Np4Pduw4CeElwkHZ6ketbGv4kxrA+p1tee5beNLVL5Vc TBLWveOF33qwdJ5+bg04Hbi1JnwxMJa4M4P6LsfLDaOD/n5Z/0qhDtpEFhS/yvVp RvAMfKVbm43wQf4Bv4kllcKEkcK65V+fLzo6KgtD1PACOlUgeE73MPykjTTVwfi0 mGvaIyCuJPg/3sNRn1f+6dktU+OS4U0kAUbbGvNXlPFVFDZfFKf5/hQvA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:date:from :in-reply-to:message-id:mime-version:references:subject:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; bh=fXphOE/P/aA++clgr5KBMvTn+12qMc94HBZ4q+3txlY=; b=GSsxn+p9 bKpmswyhtO6zIY61jKhVET1EOiwkjg4LahQaO6+4dKEj8nqt/PHA2LF97PfjJNme ZFj+PuKK8pWAi3+esx28f7g6SqKWMHZ4ICp1tlOfTls9n/ZqNBWMxmz9Vv4bYje6 vfTFwm+xFDfGiWgf1uL1wQvD4YSnYQBZxJptCQ0zuzKYL6fq1A9v4lQE3e0kwiZA pUCLfCCTCqx6Mt+fFIexLRpa+N1cF2Xuy+XFdw2jZRdJLvvqQCw0hMYm0O3GWEYP sVUCOtOHX/GUW2huqTpUQmWZP6d/FaGi1zTolG8yEfG6HY5++MgHoQBfbKGk7uCQ XBpWTi9MaxkYpQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedutddrvdeigdejtdcutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenuc fjughrpefhvffufffkofgjfhgggfestdekredtredttdenucfhrhhomhepufgrmhhuvghl ucfjohhllhgrnhguuceoshgrmhhuvghlsehshhholhhlrghnugdrohhrgheqnecukfhppe ejtddrudefhedrudegkedrudehudenucfrrghrrghmpehmrghilhhfrhhomhepshgrmhhu vghlsehshhholhhlrghnugdrohhrghenucevlhhushhtvghrufhiiigvpeek X-ME-Proxy: Received: from titanium.stl.sholland.net (70-135-148-151.lightspeed.stlsmo.sbcglobal.net [70.135.148.151]) by mail.messagingengine.com (Postfix) with ESMTPA id 0C47610310; Fri, 1 Mar 2019 23:29:59 -0500 (EST) From: Samuel Holland To: Maxime Ripard , Chen-Yu Tsai , Jassi Brar , Michael Turquette , Stephen Boyd , Rob Herring , Mark Rutland Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, Samuel Holland Subject: [PATCH v3 12/15] [NOT FOR MERGE] irqchip/mbox: Introduce a mailbox-backed irqchip driver Date: Fri, 1 Mar 2019 22:29:48 -0600 Message-Id: <20190302042951.53671-13-samuel@sholland.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20190302042951.53671-1-samuel@sholland.org> References: <20190302042951.53671-1-samuel@sholland.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This driver implements a simple interrupt controller using message passing over a mailbox channel. The intention is for the other end of the channel to be implemented in firmware. This allows filtering and forwarding interrupts from one processor to another. Signed-off-by: Samuel Holland --- drivers/irqchip/Kconfig | 9 ++ drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-mbox.c | 199 +++++++++++++++++++++++++++++++++++++ 3 files changed, 209 insertions(+) create mode 100644 drivers/irqchip/irq-mbox.c diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 3d1e60779078..d22921276797 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -406,6 +406,15 @@ config IMX_IRQSTEER help Support for the i.MX IRQSTEER interrupt multiplexer/remapper. +config IRQ_MBOX + tristate "Simple mailbox-backed interrupt controller" + depends on MAILBOX + select IRQ_DOMAIN + help + Support for interrupt controllers attached via a mailbox channel. + This allows a coprocessor to inject interrupts via a simple + message-based protocol. + endmenu config SIFIVE_PLIC diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index c93713d24b86..9de16ab4e69a 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -94,3 +94,4 @@ obj-$(CONFIG_CSKY_APB_INTC) += irq-csky-apb-intc.o obj-$(CONFIG_SIFIVE_PLIC) += irq-sifive-plic.o obj-$(CONFIG_IMX_IRQSTEER) += irq-imx-irqsteer.o obj-$(CONFIG_MADERA_IRQ) += irq-madera.o +obj-$(CONFIG_IRQ_MBOX) += irq-mbox.o diff --git a/drivers/irqchip/irq-mbox.c b/drivers/irqchip/irq-mbox.c new file mode 100644 index 000000000000..f7f6b47bc5b9 --- /dev/null +++ b/drivers/irqchip/irq-mbox.c @@ -0,0 +1,199 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (c) 2018-2019 Samuel Holland + +/* + * Simple mailbox-backed interrupt controller driver using 32-bit messages. + * The mailbox controller is expected to take a (uint32_t *) message argument. + * + * Client-to-server messages: + * Byte 3 (MSB) : Reserved + * Byte 2 : Reserved + * Byte 1 : Message type (enumerated below) + * Byte 0 (LSB) : IRQ number + * + * Server-to-client messages: + * Byte 3 (MSB) : Reserved + * Byte 2 : Reserved + * Byte 1 : Message type (must be zero == interrupt received) + * Byte 0 (LSB) : IRQ number + * + * IRQ lines must be unmasked before they can be used (generic irqchip code + * takes care of that in this driver). + */ + +#include +#include +#include +#include +#include +#include + +#define MBOX_INTC_MAX_IRQS 32 + +enum { + MSG_EOI = 0, + MSG_MASK = 1, + MSG_UNMASK = 2, +}; + +struct mbox_intc { + struct irq_chip chip; + struct irq_domain *domain; + struct mbox_chan *rx_chan; + struct mbox_chan *tx_chan; + struct mbox_client cl; +}; + +static int mbox_intc_map(struct irq_domain *domain, unsigned int virq, + irq_hw_number_t hwirq) +{ + struct mbox_intc *intc = domain->host_data; + + if (hwirq >= MBOX_INTC_MAX_IRQS) + return -ENODEV; + + irq_set_chip_data(virq, intc); + irq_set_chip_and_handler(virq, &intc->chip, handle_fasteoi_irq); + irq_set_status_flags(virq, IRQ_LEVEL); + + return 0; +} + +static const struct irq_domain_ops mbox_intc_domain_ops = { + .map = mbox_intc_map, + .xlate = irq_domain_xlate_onecell, +}; + +static void mbox_intc_rx_callback(struct mbox_client *cl, void *msg) +{ + struct mbox_intc *intc = container_of(cl, struct mbox_intc, cl); + uint32_t hwirq = *(uint32_t *)msg; + + if (hwirq >= MBOX_INTC_MAX_IRQS) + return; + + generic_handle_irq(irq_linear_revmap(intc->domain, hwirq)); +} + +static void mbox_intc_tx_msg(struct irq_data *d, uint8_t request) +{ + struct mbox_intc *intc = irq_data_get_irq_chip_data(d); + uint32_t msg = (request << 8) | (d->hwirq & GENMASK(0, 7)); + + /* Since we don't expect an ACK for this message, immediately complete + * the transmission. This ensures that each message is sent out without + * sleeping, and 'data' remains in scope until actual transmission. */ + if (mbox_send_message(intc->tx_chan, &msg) >= 0) + mbox_client_txdone(intc->tx_chan, 0); +} + +static void mbox_intc_irq_mask(struct irq_data *d) +{ + mbox_intc_tx_msg(d, MSG_MASK); +} + +static void mbox_intc_irq_unmask(struct irq_data *d) +{ + mbox_intc_tx_msg(d, MSG_UNMASK); +} + +static void mbox_intc_irq_eoi(struct irq_data *d) +{ + mbox_intc_tx_msg(d, MSG_EOI); +} + +static int mbox_intc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mbox_intc *intc; + int ret; + + intc = devm_kzalloc(dev, sizeof(*intc), GFP_KERNEL); + if (!intc) + return -ENOMEM; + + intc->cl.dev = dev; + intc->cl.knows_txdone = true; + intc->cl.rx_callback = mbox_intc_rx_callback; + + if (of_get_property(dev->of_node, "mbox-names", NULL)) { + intc->rx_chan = mbox_request_channel_byname(&intc->cl, "rx"); + if (IS_ERR(intc->rx_chan)) { + ret = PTR_ERR(intc->rx_chan); + dev_err(dev, "Failed to request rx mailbox channel\n"); + goto err; + } + intc->tx_chan = mbox_request_channel_byname(&intc->cl, "tx"); + if (IS_ERR(intc->tx_chan)) { + ret = PTR_ERR(intc->tx_chan); + dev_err(dev, "Failed to request tx mailbox channel\n"); + goto err_free_rx_chan; + } + } else { + intc->rx_chan = mbox_request_channel(&intc->cl, 0); + intc->tx_chan = intc->rx_chan; + if (IS_ERR(intc->tx_chan)) { + ret = PTR_ERR(intc->tx_chan); + dev_err(dev, "Failed to request mailbox channel\n"); + goto err; + } + } + + intc->chip.name = dev_name(dev); + intc->chip.irq_mask = mbox_intc_irq_mask; + intc->chip.irq_unmask = mbox_intc_irq_unmask; + intc->chip.irq_eoi = mbox_intc_irq_eoi; + + intc->domain = irq_domain_add_linear(dev->of_node, MBOX_INTC_MAX_IRQS, + &mbox_intc_domain_ops, intc); + if (IS_ERR(intc->domain)) { + ret = PTR_ERR(intc->domain); + dev_err(dev, "Failed to allocate IRQ domain: %d\n", ret); + goto err_free_tx_chan; + } + + platform_set_drvdata(pdev, intc); + + return 0; + +err_free_tx_chan: + if (intc->tx_chan != intc->rx_chan) + mbox_free_channel(intc->tx_chan); +err_free_rx_chan: + mbox_free_channel(intc->rx_chan); +err: + return ret; +} + +static int mbox_intc_remove(struct platform_device *pdev) +{ + struct mbox_intc *intc = platform_get_drvdata(pdev); + + irq_domain_remove(intc->domain); + if (intc->tx_chan != intc->rx_chan) + mbox_free_channel(intc->tx_chan); + mbox_free_channel(intc->rx_chan); + + return 0; +} + +static const struct of_device_id mbox_intc_of_match[] = { + { .compatible = "allwinner,sunxi-msgbox-intc" }, + {}, +}; +MODULE_DEVICE_TABLE(of, mbox_intc_of_match); + +static struct platform_driver mbox_intc_driver = { + .driver = { + .name = KBUILD_MODNAME, + .of_match_table = mbox_intc_of_match, + }, + .probe = mbox_intc_probe, + .remove = mbox_intc_remove, +}; +module_platform_driver(mbox_intc_driver); + +MODULE_AUTHOR("Samuel Holland "); +MODULE_DESCRIPTION("Simple mailbox-backed interrupt controller"); +MODULE_LICENSE("GPL v2"); -- 2.19.2