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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 A623DC433ED for ; Mon, 22 Mar 2021 18:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93C01619A0 for ; Mon, 22 Mar 2021 18:47:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231285AbhCVSqj (ORCPT ); Mon, 22 Mar 2021 14:46:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:33244 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229951AbhCVSq1 (ORCPT ); Mon, 22 Mar 2021 14:46:27 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2A7DE619A7; Mon, 22 Mar 2021 18:46:27 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1lOPZJ-0038p5-E2; Mon, 22 Mar 2021 18:46:25 +0000 From: Marc Zyngier To: Lorenzo Pieralisi , Bjorn Helgaas Cc: Frank Wunderlich , Thierry Reding , Thomas Gleixner , Rob Herring , Will Deacon , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Michael Kelley , Wei Liu , Thierry Reding , Jonathan Hunter , Ryder Lee , Marek Vasut , Yoshihiro Shimoda , Michal Simek , Paul Walmsley , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-tegra@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-renesas-soc@vger.kernel.org, kernel-team@android.com Subject: [PATCH v2 02/15] PCI: rcar: Don't allocate extra memory for the MSI capture address Date: Mon, 22 Mar 2021 18:46:01 +0000 Message-Id: <20210322184614.802565-3-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210322184614.802565-1-maz@kernel.org> References: <20210322184614.802565-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: lorenzo.pieralisi@arm.com, bhelgaas@google.com, frank-w@public-files.de, treding@nvidia.com, tglx@linutronix.de, robh@kernel.org, will@kernel.org, kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, mikelley@microsoft.com, wei.liu@kernel.org, thierry.reding@gmail.com, jonathanh@nvidia.com, ryder.lee@mediatek.com, marek.vasut+renesas@gmail.com, yoshihiro.shimoda.uh@renesas.com, michal.simek@xilinx.com, paul.walmsley@sifive.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-tegra@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-renesas-soc@vger.kernel.org, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org A long cargo-culted behaviour of PCI drivers is to allocate memory to obtain an address that is fed to the controller as the MSI capture address (i.e. the MSI doorbell). But there is no actual requirement for this address to be RAM. All it needs to be is a suitable aligned address that will *not* be DMA'd to. Since the rcar platform already has a requirement that this address should be in the first 4GB of the physical address space, use the controller's own base address as the capture address. Signed-off-by: Marc Zyngier --- drivers/pci/controller/pcie-rcar-host.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index a728e8f9ad3c..ce952403e22c 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -36,7 +36,6 @@ struct rcar_msi { DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; struct msi_controller chip; - unsigned long pages; struct mutex lock; int irq1; int irq2; @@ -680,14 +679,15 @@ static void rcar_pcie_unmap_msi(struct rcar_pcie_host *host) static void rcar_pcie_hw_enable_msi(struct rcar_pcie_host *host) { struct rcar_pcie *pcie = &host->pcie; - struct rcar_msi *msi = &host->msi; - unsigned long base; + struct device *dev = pcie->dev; + struct resource res; - /* setup MSI data target */ - base = virt_to_phys((void *)msi->pages); + if (WARN_ON(of_address_to_resource(dev->of_node, 0, &res))) + return; - rcar_pci_write_reg(pcie, lower_32_bits(base) | MSIFE, PCIEMSIALR); - rcar_pci_write_reg(pcie, upper_32_bits(base), PCIEMSIAUR); + /* setup MSI data target */ + rcar_pci_write_reg(pcie, lower_32_bits(res.start) | MSIFE, PCIEMSIALR); + rcar_pci_write_reg(pcie, upper_32_bits(res.start), PCIEMSIAUR); /* enable all MSI interrupts */ rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER); @@ -735,7 +735,6 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) } /* setup MSI data target */ - msi->pages = __get_free_pages(GFP_KERNEL | GFP_DMA32, 0); rcar_pcie_hw_enable_msi(host); return 0; @@ -748,7 +747,6 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host) { struct rcar_pcie *pcie = &host->pcie; - struct rcar_msi *msi = &host->msi; /* Disable all MSI interrupts */ rcar_pci_write_reg(pcie, 0, PCIEMSIIER); @@ -756,8 +754,6 @@ static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host) /* Disable address decoding of the MSI interrupt, MSIFE */ rcar_pci_write_reg(pcie, 0, PCIEMSIALR); - free_pages(msi->pages, 0); - rcar_pcie_unmap_msi(host); } -- 2.29.2