From patchwork Fri Nov 3 13:47:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Cassel X-Patchwork-Id: 833882 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 3yT3LC0pn1z9sNc for ; Sat, 4 Nov 2017 00:52:35 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756315AbdKCNwG (ORCPT ); Fri, 3 Nov 2017 09:52:06 -0400 Received: from bastet.se.axis.com ([195.60.68.11]:51488 "EHLO bastet.se.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756307AbdKCNrk (ORCPT ); Fri, 3 Nov 2017 09:47:40 -0400 Received: from localhost (localhost [127.0.0.1]) by bastet.se.axis.com (Postfix) with ESMTP id B7DC41896E; Fri, 3 Nov 2017 14:47:38 +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 ljPNEtnbxWh1; Fri, 3 Nov 2017 14:47:36 +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 7582118945; Fri, 3 Nov 2017 14:47:36 +0100 (CET) Received: from boulder03.se.axis.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 42DA01E07F; Fri, 3 Nov 2017 14:47:36 +0100 (CET) Received: from boulder03.se.axis.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3524C1E07C; Fri, 3 Nov 2017 14:47:36 +0100 (CET) Received: from seth.se.axis.com (unknown [10.0.2.172]) by boulder03.se.axis.com (Postfix) with ESMTP; Fri, 3 Nov 2017 14:47:36 +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 289CE2629; Fri, 3 Nov 2017 14:47:36 +0100 (CET) Received: by lnxartpec1.se.axis.com (Postfix, from userid 20283) id 2507340101; Fri, 3 Nov 2017 14:47:36 +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 v4 01/17] PCI: dwc: Use the DMA-API to get the MSI address Date: Fri, 3 Nov 2017 14:47:05 +0100 Message-Id: <20171103134722.5532-2-niklas.cassel@axis.com> X-Mailer: git-send-email 2.14.2 In-Reply-To: <20171103134722.5532-1-niklas.cassel@axis.com> References: <20171103134722.5532-1-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 Use the DMA-API to get the MSI address. This address will be written to our PCI config space and to the register which determines which AXI address the DWC IP will spoof for incoming MSI irqs. Since it is a PCIe endpoint device, rather than the CPU, that is supposed to write to the MSI address, the proper way to get the MSI address is by using the DMA API, not by using virt_to_phys(). Using virt_to_phys() might work on some systems, but using the DMA API should 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 --- 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); };