From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752533AbdKHMqW (ORCPT ); Wed, 8 Nov 2017 07:46:22 -0500 Received: from us01smtprelay-2.synopsys.com ([198.182.47.9]:59695 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751931AbdKHMqV (ORCPT ); Wed, 8 Nov 2017 07:46:21 -0500 Subject: Re: [PATCH v4 01/17] PCI: dwc: Use the DMA-API to get the MSI address To: Bjorn Helgaas , Niklas Cassel CC: Jingoo Han , Joao Pinto , Bjorn Helgaas , Niklas Cassel , , References: <20171103134722.5532-1-niklas.cassel@axis.com> <20171103134722.5532-2-niklas.cassel@axis.com> <20171108005614.GF22847@bhelgaas-glaptop.roam.corp.google.com> From: Joao Pinto Message-ID: <1c059ad0-aa57-fca4-6d92-e68736ffad5f@synopsys.com> Date: Wed, 8 Nov 2017 12:45:49 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: <20171108005614.GF22847@bhelgaas-glaptop.roam.corp.google.com> Content-Type: text/plain; charset="utf-8" Content-Language: pt-PT Content-Transfer-Encoding: 8bit X-Originating-IP: [10.107.19.95] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello to all, Às 12:56 AM de 11/8/2017, Bjorn Helgaas escreveu: > On Fri, Nov 03, 2017 at 02:47:05PM +0100, Niklas Cassel wrote: >> 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 > > I'm expecting Jingoo and/or Joao to chime in and ack the > DesignWare-related patches. I think all the others are in > pretty good shape. > >> --- >> drivers/pci/dwc/pcie-designware-host.c | 15 ++++++++++++--- >> drivers/pci/dwc/pcie-designware.h | 3 ++- >> 2 files changed, 14 insertions(+), 4 deletions(-) >> ... Let me test this patch-set in my setup first! I will give feedback until Friday. Thanks, Joao