From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33090) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqIpD-0002ru-Mk for qemu-devel@nongnu.org; Mon, 17 Nov 2014 04:42:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqIp6-0000rS-BW for qemu-devel@nongnu.org; Mon, 17 Nov 2014 04:42:23 -0500 Received: from mga09.intel.com ([134.134.136.24]:42856) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqIp6-0000rF-4q for qemu-devel@nongnu.org; Mon, 17 Nov 2014 04:42:16 -0500 Message-ID: <5469C2F4.4020304@intel.com> Date: Mon, 17 Nov 2014 17:42:12 +0800 From: "Chen, Tiejun" MIME-Version: 1.0 References: <1415172179-7965-1-git-send-email-tiejun.chen@intel.com> <1415172179-7965-2-git-send-email-tiejun.chen@intel.com> <20141105140906.GA4912@redhat.com> <546961DC.4040300@intel.com> <20141117061010.GB19718@redhat.com> <5469B660.6040107@intel.com> <20141117092501.GA20133@redhat.com> In-Reply-To: <20141117092501.GA20133@redhat.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC][PATCH 2/2] xen:i386:pc_piix: create isa bridge specific to IGD passthrough List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: xen-devel@lists.xensource.com, allen.m.kay@intel.com, qemu-devel@nongnu.org, aliguori@amazon.com, pbonzini@redhat.com, rth@twiddle.net On 2014/11/17 17:25, Michael S. Tsirkin wrote: > On Mon, Nov 17, 2014 at 04:48:32PM +0800, Chen, Tiejun wrote: >> On 2014/11/17 14:10, Michael S. Tsirkin wrote: >>> On Mon, Nov 17, 2014 at 10:47:56AM +0800, Chen, Tiejun wrote: >>>> On 2014/11/5 22:09, Michael S. Tsirkin wrote: >>>>> On Wed, Nov 05, 2014 at 03:22:59PM +0800, Tiejun Chen wrote: >>>>>> Currently IGD drivers always need to access PCH by 1f.0, and >>>>>> PCH vendor/device id is used to identify the card. >>>>>> >>>>>> Signed-off-by: Tiejun Chen >>>>>> --- [snip] > Cleaner: > if (!pci_dev) { > fprintf > return; > } > pci_config_set_device_id(pci_dev->config, pch_id); I will address all comments and thanks. > >> + } >> +} >> + >> /* init */ >> >> static int xen_pt_initfn(PCIDevice *d) >> @@ -682,6 +770,9 @@ static int xen_pt_initfn(PCIDevice *d) >> return -1; >> } >> >> + /* Register ISA bridge for passthrough GFX. */ >> + xen_igd_passthrough_isa_bridge_create(s, &s->real_device); >> + >> /* reinitialize each config register to be emulated */ >> if (xen_pt_config_init(s)) { >> XEN_PT_ERR(d, "PCI Config space initialisation failed.\n"); >> >> Note I will introduce a inline function in another patch, >> >> +static inline int is_vga_passthrough(XenHostPCIDevice *dev) >> +{ >> + return (xen_has_gfx_passthru && (dev->vendor_id == PCI_VENDOR_ID_INTEL) >> + && ((dev->class_code >> 0x8) == PCI_CLASS_DISPLAY_VGA)); >> +} >> >> Thanks >> Tiejun > > Why bother with all these conditions? > Won't it be enough to check dev->vendor_id == PCI_VENDOR_ID_INTEL? > If this is just used for IGD, its always fine without checking vendor_id. So after remove that check, I guess I need to rename that as is_igd_vga_passthrough() to make sense. Thanks Tiejun