From patchwork Tue Oct 31 22:39:19 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Cassel X-Patchwork-Id: 832773 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yRRKd25m8z9t4X for ; Wed, 1 Nov 2017 09:46:29 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754002AbdJaWq0 (ORCPT ); Tue, 31 Oct 2017 18:46:26 -0400 Received: from bastet.se.axis.com ([195.60.68.11]:52251 "EHLO bastet.se.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753706AbdJaWjp (ORCPT ); Tue, 31 Oct 2017 18:39:45 -0400 Received: from localhost (localhost [127.0.0.1]) by bastet.se.axis.com (Postfix) with ESMTP id 3844F1842D; Tue, 31 Oct 2017 23:39:43 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at bastet.se.axis.com Received: from bastet.se.axis.com ([IPv6:::ffff:127.0.0.1]) by localhost (bastet.se.axis.com [::ffff:127.0.0.1]) (amavisd-new, port 10024) with LMTP id VBetFrxTe01k; Tue, 31 Oct 2017 23:39:39 +0100 (CET) Received: from boulder03.se.axis.com (boulder03.se.axis.com [10.0.8.17]) by bastet.se.axis.com (Postfix) with ESMTPS id 24B4C18733; Tue, 31 Oct 2017 23:39:39 +0100 (CET) Received: from boulder03.se.axis.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 02FF21E096; Tue, 31 Oct 2017 23:39:39 +0100 (CET) Received: from boulder03.se.axis.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EB7211E093; Tue, 31 Oct 2017 23:39:38 +0100 (CET) Received: from seth.se.axis.com (unknown [10.0.2.172]) by boulder03.se.axis.com (Postfix) with ESMTP; Tue, 31 Oct 2017 23:39:38 +0100 (CET) Received: from lnxartpec1.se.axis.com (lnxartpec1.se.axis.com [10.88.4.10]) by seth.se.axis.com (Postfix) with ESMTP id DEEC52331; Tue, 31 Oct 2017 23:39:38 +0100 (CET) Received: by lnxartpec1.se.axis.com (Postfix, from userid 20283) id D92C340101; Tue, 31 Oct 2017 23:39:38 +0100 (CET) From: Niklas Cassel To: Jingoo Han , Joao Pinto , Bjorn Helgaas Cc: Niklas Cassel , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 01/17] PCI: dwc: Use DMA-API for allocating MSI data Date: Tue, 31 Oct 2017 23:39:19 +0100 Message-Id: <20171031223936.27549-2-niklas.cassel@axis.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20171031223936.27549-1-niklas.cassel@axis.com> References: <20171031223936.27549-1-niklas.cassel@axis.com> X-TM-AS-GCONF: 00 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Since it is a PCIe endpoint device, rather than the CPU, that is supposed to write to this location, the proper way to get the address to this this location is really to use the DMA API, rather than virt_to_phys. Using virt_to_phys might work on some systems, but by using the DMA API, we know that it will work on all systems. This is essentially the same thing as allocating a buffer in a driver, to which the endpoint will write to. To do this, we use the DMA API. Signed-off-by: Niklas Cassel --- V3: * No change. drivers/pci/dwc/pcie-designware-host.c | 15 ++++++++++++--- drivers/pci/dwc/pcie-designware.h | 3 ++- 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c index 81e2157a7cfb..33b52fe98a01 100644 --- a/drivers/pci/dwc/pcie-designware-host.c +++ b/drivers/pci/dwc/pcie-designware-host.c @@ -83,10 +83,19 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp) void dw_pcie_msi_init(struct pcie_port *pp) { + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); + struct device *dev = pci->dev; + struct page *page; u64 msi_target; - pp->msi_data = __get_free_pages(GFP_KERNEL, 0); - msi_target = virt_to_phys((void *)pp->msi_data); + page = alloc_page(GFP_KERNEL | GFP_DMA32); + pp->msi_data = dma_map_page(dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE); + if (dma_mapping_error(dev, pp->msi_data)) { + dev_err(dev, "failed to map MSI data\n"); + __free_page(page); + return; + } + msi_target = (u64)pp->msi_data; /* program the msi_data */ dw_pcie_wr_own_conf(pp, PCIE_MSI_ADDR_LO, 4, @@ -187,7 +196,7 @@ static void dw_msi_setup_msg(struct pcie_port *pp, unsigned int irq, u32 pos) if (pp->ops->get_msi_addr) msi_target = pp->ops->get_msi_addr(pp); else - msi_target = virt_to_phys((void *)pp->msi_data); + msi_target = (u64)pp->msi_data; msg.address_lo = (u32)(msi_target & 0xffffffff); msg.address_hi = (u32)(msi_target >> 32 & 0xffffffff); diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h index e5d9d77b778e..ecdede68522a 100644 --- a/drivers/pci/dwc/pcie-designware.h +++ b/drivers/pci/dwc/pcie-designware.h @@ -14,6 +14,7 @@ #ifndef _PCIE_DESIGNWARE_H #define _PCIE_DESIGNWARE_H +#include #include #include #include @@ -168,7 +169,7 @@ struct pcie_port { const struct dw_pcie_host_ops *ops; int msi_irq; struct irq_domain *irq_domain; - unsigned long msi_data; + dma_addr_t msi_data; DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS); };