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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8785C43334 for ; Thu, 23 Jun 2022 16:28:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231281AbiFWQ1w (ORCPT ); Thu, 23 Jun 2022 12:27:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58674 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230372AbiFWQ1v (ORCPT ); Thu, 23 Jun 2022 12:27:51 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 48C1345505; Thu, 23 Jun 2022 09:27:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D571D61F29; Thu, 23 Jun 2022 16:27:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D56B7C3411B; Thu, 23 Jun 2022 16:27:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656001669; bh=mQ/fn0p8cPl4WB2QzHrDHEEQ5APApuVeWejOBIseoBo=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=CXItkpNMNvxD7QoYxGuICkZjHYpIyeXGmsSznqc6onqqP9Yaogh5wQYLy0mxK2SVF 0kF1LS4itKDyL9o3aZhGuI0wM3MCK8biKylavp+HpFWn2vsGhpiL+zWOa10zykwDmK nhW0o8lNSvfxT/J55BKAXCKYOa0eLKlIhzlBD1+YQu6RlN5QrqxMSUjKm3Cf8yMmzv QC1/YK6hYvvHSQWiUzqofQzI1LMRnUaIcq837L4Y9YYCRlLbXKTJ9hDoyLrU/xI65N v7je9R4R6Y9pUMRJjMsJK5hjkHIZXBOwqDDUBMSWpN3RhhqDiRUc1R/75LFE8U4bLZ ltz0W0KD8CtaA== Date: Thu, 23 Jun 2022 11:27:47 -0500 From: Bjorn Helgaas To: Pali =?iso-8859-1?Q?Roh=E1r?= Cc: Bjorn Helgaas , Thomas Petazzoni , Lorenzo Pieralisi , Rob Herring , Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: mvebu: Use devm_request_irq() for registering interrupt handler Message-ID: <20220623162747.GA1455992@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220524122817.7199-1-pali@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, May 24, 2022 at 02:28:17PM +0200, Pali Rohár wrote: > Same as in commit a3b69dd0ad62 ("Revert "PCI: aardvark: Rewrite IRQ code to > chained IRQ handler"") for pci-aardvark driver, use devm_request_irq() > instead of chained IRQ handler in pci-mvebu.c driver. > > This change fixes affinity support and allows to pin interrupts from > different PCIe controllers to different CPU cores. Several other drivers use irq_set_chained_handler_and_data(). Do any of them need similar changes? The commit log suggests that using chained IRQ handlers breaks affinity support. But perhaps that's not the case and the real culprit is some other difference between mvebu and the other drivers. > Fixes: ec075262648f ("PCI: mvebu: Implement support for legacy INTx interrupts") > Signed-off-by: Pali Rohár > --- > Hello Bjorn! This is basically same issue as for pci-aardvark.c: > https://lore.kernel.org/linux-pci/20220515125815.30157-1-pali@kernel.org/#t > > I tested this patch with pci=nomsi in cmdline (to force kernel to use > legacy intx instead of MSI) on A385 and checked that I can set affinity > via /proc/irq/XX/smp_affinity file for every mvebu pcie controller to > different CPU and legacy interrupts from different cards/controllers > were handled by different CPUs. > > I think that this is important on Armada XP platforms which have many > independent PCIe controllers (IIRC up to 10) and many cores (up to 4). > --- > drivers/pci/controller/pci-mvebu.c | 30 +++++++++++++++++------------- > 1 file changed, 17 insertions(+), 13 deletions(-) > > diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c > index 8f76d4bda356..de67ea39fea5 100644 > --- a/drivers/pci/controller/pci-mvebu.c > +++ b/drivers/pci/controller/pci-mvebu.c > @@ -1017,16 +1017,13 @@ static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port) > return 0; > } > > -static void mvebu_pcie_irq_handler(struct irq_desc *desc) > +static irqreturn_t mvebu_pcie_irq_handler(int irq, void *arg) > { > - struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc); > - struct irq_chip *chip = irq_desc_get_chip(desc); > + struct mvebu_pcie_port *port = arg; > struct device *dev = &port->pcie->pdev->dev; > u32 cause, unmask, status; > int i; > > - chained_irq_enter(chip, desc); > - > cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF); > unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF); > status = cause & unmask; > @@ -1040,7 +1037,7 @@ static void mvebu_pcie_irq_handler(struct irq_desc *desc) > dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A'); > } > > - chained_irq_exit(chip, desc); > + return status ? IRQ_HANDLED : IRQ_NONE; > } > > static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) > @@ -1490,9 +1487,20 @@ static int mvebu_pcie_probe(struct platform_device *pdev) > mvebu_pcie_powerdown(port); > continue; > } > - irq_set_chained_handler_and_data(irq, > - mvebu_pcie_irq_handler, > - port); > + > + ret = devm_request_irq(dev, irq, mvebu_pcie_irq_handler, > + IRQF_SHARED | IRQF_NO_THREAD, > + port->name, port); > + if (ret) { > + dev_err(dev, "%s: cannot register interrupt handler: %d\n", > + port->name, ret); > + irq_domain_remove(port->intx_irq_domain); > + pci_bridge_emul_cleanup(&port->bridge); > + devm_iounmap(dev, port->base); > + port->base = NULL; > + mvebu_pcie_powerdown(port); > + continue; > + } > } > > /* > @@ -1599,7 +1607,6 @@ static int mvebu_pcie_remove(struct platform_device *pdev) > > for (i = 0; i < pcie->nports; i++) { > struct mvebu_pcie_port *port = &pcie->ports[i]; > - int irq = port->intx_irq; > > if (!port->base) > continue; > @@ -1615,9 +1622,6 @@ static int mvebu_pcie_remove(struct platform_device *pdev) > /* Clear all interrupt causes. */ > mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF); > > - if (irq > 0) > - irq_set_chained_handler_and_data(irq, NULL, NULL); > - > /* Remove IRQ domains. */ > if (port->intx_irq_domain) > irq_domain_remove(port->intx_irq_domain); > -- > 2.20.1 >