qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Chen, Tiejun" <tiejun.chen@intel.com>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: peter.maydell@linaro.org, xen-devel@lists.xensource.com,
	stefano.stabellini@eu.citrix.com, allen.m.kay@intel.com,
	qemu-devel@nongnu.org, Kelly.Zytaruk@amd.com,
	yang.z.zhang@intel.com, anthony@codemonkey.ws,
	anthony.perard@citrix.com, pbonzini@redhat.com
Subject: Re: [Qemu-devel] [v5][PATCH 2/5] xen, gfx passthrough: create pseudo intel isa bridge
Date: Wed, 25 Jun 2014 16:10:44 +0800	[thread overview]
Message-ID: <53AA8404.8040708@intel.com> (raw)
In-Reply-To: <20140625064545.GB25563@redhat.com>

On 2014/6/25 14:45, Michael S. Tsirkin wrote:
> On Wed, Jun 25, 2014 at 10:17:18AM +0800, Tiejun Chen wrote:
>> ISA bridge is needed since Intel gfx drive will probe with Dev31:Fun0
>> to make graphics device passthrough work well for VMM, that only need
>> to expose this pseudo ISA bridge to let driver know the real hardware
>> underneath.
>>
>> The original patch is from Allen Kay <allen.m.kay@intel.com>
>>
>> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
>> Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
>> Cc: Allen Kay <allen.m.kay@intel.com>
>> ---
>> v5:
>>
>> * Don't set this ISA class property, instead, just fake this ISA bridge
>>    with 00:1f.0.
>>
>> v4:
>>
>> * Remove some unnecessary "return" in void foo().
>>
>> v3:
>>
>> * Fix some typos.
>> * Improve some return paths.
>>
>> v2:
>>
>> * Nothing is changed.
>>
>>   hw/xen/xen_pt_graphics.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 61 insertions(+)
>>
>> diff --git a/hw/xen/xen_pt_graphics.c b/hw/xen/xen_pt_graphics.c
>> index 461e526..974b7e9 100644
>> --- a/hw/xen/xen_pt_graphics.c
>> +++ b/hw/xen/xen_pt_graphics.c
>> @@ -230,3 +230,64 @@ out:
>>       g_free(bios);
>>       return rc;
>>   }
>> +
>> +static uint32_t isa_bridge_read_config(PCIDevice *d, uint32_t addr, int len)
>> +{
>> +    return pci_default_read_config(d, addr, len);
>> +}
>> +
>> +static void isa_bridge_write_config(PCIDevice *d, uint32_t addr, uint32_t v,
>> +                                    int len)
>> +{
>> +    pci_default_write_config(d, addr, v, len);
>> +}
>> +
>> +static void isa_bridge_class_init(ObjectClass *klass, void *data)
>> +{
>> +    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
>> +
>> +    k->config_read = isa_bridge_read_config;
>> +    k->config_write = isa_bridge_write_config;
>> +};
>
> You don't need these stubs, just don't fill anything,
> pci core will use defaults then.

I guess these stubs are left to extend something in the future. But 
maybe we can remove them now.

>
>> +
>> +typedef struct {
>> +    PCIDevice dev;
>> +} ISABridgeState;
>> +
>
> Nor do you need an empty structure if it has no state.
>
>> +static TypeInfo isa_bridge_info = {
>> +    .name          = "pseudo-intel-pch-isa-bridge",
>> +    .parent        = TYPE_PCI_DEVICE,
>> +    .instance_size = sizeof(ISABridgeState),
>> +    .class_init = isa_bridge_class_init,
>> +};
>> +
>> +static void xen_pt_graphics_register_types(void)
>> +{
>> +    type_register_static(&isa_bridge_info);
>> +}
>> +
>> +type_init(xen_pt_graphics_register_types)
>> +
>> +static int create_pseudo_pch_isa_bridge(PCIBus *bus, XenHostPCIDevice *hdev)
>> +{
>> +    struct PCIDevice *dev;
>> +
>> +    char rid;
>> +
>> +    /* We havt to use a simple PCI device to fake this ISA bridge
>> +     * to avoid making some confusion to BIOS and ACPI.
>> +     */
>
> A typo and confusing wording above, I'm not really
> sure what this comment means.
> Maybe:
>
> /* Create a fake ISA bridge device at the location expected by guests. */
>

Good comments so thanks so much.

>
>> +    dev = pci_create(bus, PCI_DEVFN(0x1f, 0), "pseudo-intel-pch-isa-bridge");
>> +
>> +    qdev_init_nofail(&dev->qdev);
>> +
>> +    pci_config_set_vendor_id(dev->config, hdev->vendor_id);
>> +    pci_config_set_device_id(dev->config, hdev->device_id);
>> +
>> +    xen_host_pci_get_block(hdev, PCI_REVISION_ID, (uint8_t *)&rid, 1);
>
> Host PCI device is the VGA card?

This is a real ISA bridge.

> So why does it make sense to get it's vendor/device/revision and
> stick in the ISA bridge?

The Intel generation of integrated graphics needs to probe this ISA 
bridge to initialize the i915 driver properly.

Thanks
Tiejun

>
> Also change rid to uint8_t, you won't need to cast then.
>
>> +
>> +    pci_config_set_revision(dev->config, rid);
>> +
>> +    XEN_PT_LOG(dev, "The pseudo Intel PCH ISA bridge created.\n");
>> +    return 0;
>> +}
>> --
>> 1.9.1
>
>

  reply	other threads:[~2014-06-25  8:11 UTC|newest]

Thread overview: 169+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-25  2:17 [Qemu-devel] [v5][PATCH 0/5] xen: add Intel IGD passthrough support Tiejun Chen
2014-06-25  2:17 ` [Qemu-devel] [v5][PATCH 1/5] xen, gfx passthrough: basic graphics " Tiejun Chen
2014-06-25  6:21   ` Paolo Bonzini
2014-06-25  7:48     ` Chen, Tiejun
2014-06-25  6:35   ` Michael S. Tsirkin
2014-06-25  9:06     ` Chen, Tiejun
2014-06-25  9:16       ` Michael S. Tsirkin
2014-06-25  2:17 ` [Qemu-devel] [v5][PATCH 2/5] xen, gfx passthrough: create pseudo intel isa bridge Tiejun Chen
2014-06-25  6:22   ` Paolo Bonzini
2014-06-25  7:51     ` Chen, Tiejun
2014-06-25  6:45   ` Michael S. Tsirkin
2014-06-25  8:10     ` Chen, Tiejun [this message]
2014-06-25  8:28       ` Michael S. Tsirkin
2014-06-25  8:39         ` Chen, Tiejun
2014-06-25  8:43           ` Michael S. Tsirkin
2014-06-25  8:48             ` Chen, Tiejun
2014-06-25  9:04               ` Michael S. Tsirkin
2014-06-25  9:14                 ` Chen, Tiejun
2014-06-25  9:21                   ` Michael S. Tsirkin
2014-06-25  9:28                     ` Chen, Tiejun
2014-06-25  9:44                       ` Michael S. Tsirkin
2014-06-25  9:58                         ` Chen, Tiejun
2014-06-27  7:22                           ` Chen, Tiejun
2014-06-30 19:34                             ` Stefano Stabellini
2014-07-01  2:21                               ` Chen, Tiejun
2014-07-01  5:47                               ` Michael S. Tsirkin
2014-07-01  9:50                                 ` Chen, Tiejun
2014-07-01 12:34                                   ` Michael S. Tsirkin
2014-07-01 16:51                                 ` Stefano Stabellini
2014-06-25  2:17 ` [Qemu-devel] [v5][PATCH 3/5] xen, gfx passthrough: support Intel IGD passthrough with VT-D Tiejun Chen
2014-06-25  6:25   ` Paolo Bonzini
2014-06-25  7:54     ` Chen, Tiejun
2014-06-25  7:04   ` Michael S. Tsirkin
2014-06-27  9:16     ` Chen, Tiejun
2014-06-25 14:05   ` Michael S. Tsirkin
2014-06-26  5:34     ` Chen, Tiejun
2014-06-26  6:04       ` Michael S. Tsirkin
2014-06-26  8:26         ` Chen, Tiejun
2014-06-25  2:17 ` [Qemu-devel] [v5][PATCH 4/5] xen, gfx passthrough: create host bridge to passthrough Tiejun Chen
2014-06-25  6:24   ` Paolo Bonzini
2014-06-27  8:34     ` Chen, Tiejun
2014-06-27 11:26       ` Paolo Bonzini
2014-06-29  7:56         ` Chen, Tiejun
2014-06-29 12:14           ` Michael S. Tsirkin
2014-06-30  2:52             ` Chen, Tiejun
2014-06-30 19:42               ` Stefano Stabellini
2014-07-01  2:19                 ` Chen, Tiejun
2014-07-01 16:49                   ` Stefano Stabellini
2014-07-01 18:34                     ` Michael S. Tsirkin
2014-07-01 18:45                       ` Michael S. Tsirkin
2014-06-25  2:17 ` [Qemu-devel] [v5][PATCH 5/5] xen, gfx passthrough: add opregion mapping Tiejun Chen
2014-06-25  7:13   ` Michael S. Tsirkin
2014-06-27  9:22     ` Chen, Tiejun
2014-06-29 11:43       ` Michael S. Tsirkin
2014-06-30  0:57         ` Chen, Tiejun
2014-06-25  6:19 ` [Qemu-devel] [v5][PATCH 0/5] xen: add Intel IGD passthrough support Paolo Bonzini
2014-06-25  7:15   ` Michael S. Tsirkin
2014-06-25  7:56     ` Paolo Bonzini
2014-06-25  7:35   ` Chen, Tiejun
2014-06-25  7:40     ` Michael S. Tsirkin
2014-06-25  7:44     ` Paolo Bonzini
2014-06-25  8:31       ` Michael S. Tsirkin
2014-06-25  8:39         ` Paolo Bonzini
2014-06-25  8:48           ` Michael S. Tsirkin
2014-06-25  8:55             ` Chen, Tiejun
2014-06-25  9:09               ` Michael S. Tsirkin
2014-06-25  9:21                 ` Chen, Tiejun
2014-06-25  9:31                   ` Paolo Bonzini
2014-06-25  9:50                     ` Chen, Tiejun
2014-06-25  9:54                       ` Paolo Bonzini
2014-06-25 10:00                         ` Michael S. Tsirkin
2014-06-26  9:18                         ` Chen, Tiejun
2014-06-26 10:03                           ` Paolo Bonzini
2014-06-26 11:26                             ` Michael S. Tsirkin
2014-06-26 11:30                               ` Paolo Bonzini
2014-06-26 11:36                                 ` Michael S. Tsirkin
2014-06-26 13:30                                   ` Paolo Bonzini
2014-06-26 15:40                                     ` Michael S. Tsirkin
2014-06-30  2:51                             ` Chen, Tiejun
2014-06-30  6:48                               ` Michael S. Tsirkin
2014-06-30  7:24                                 ` Chen, Tiejun
2014-06-30  9:05                                   ` Michael S. Tsirkin
2014-06-30  9:38                                     ` Chen, Tiejun
2014-06-30  9:55                                       ` Michael S. Tsirkin
2014-06-30 10:20                                         ` [Qemu-devel] [Xen-devel] " Chen, Tiejun
2014-06-30 11:18                                           ` Paolo Bonzini
2014-06-30 11:31                                             ` Michael S. Tsirkin
2014-06-30 11:28                                           ` Michael S. Tsirkin
2014-07-01  2:40                                             ` Chen, Tiejun
2014-07-01  9:12                                               ` Michael S. Tsirkin
2014-07-01  9:46                                                 ` Chen, Tiejun
2014-07-01 12:33                                                   ` Michael S. Tsirkin
2014-07-02  0:59                                                     ` Chen, Tiejun
2014-07-02  6:22                                                       ` Michael S. Tsirkin
2014-07-02  8:45                                                         ` Chen, Tiejun
2014-06-30 19:22                                     ` [Qemu-devel] " Stefano Stabellini
2014-06-30 19:31                                       ` [Qemu-devel] [Xen-devel] " Ross Philipson
2014-07-01  2:24                                         ` Chen, Tiejun
2014-07-01  5:39                                         ` Michael S. Tsirkin
2014-07-01 16:47                                           ` Stefano Stabellini
2014-07-01 17:02                                             ` Michael S. Tsirkin
2014-07-01 17:39                                               ` Ross Philipson
2014-07-01 18:06                                                 ` Michael S. Tsirkin
2014-07-01 19:29                                                   ` Ross Philipson
2014-07-02  6:11                                                     ` Michael S. Tsirkin
2014-07-02  7:56                                                       ` Chen, Tiejun
2014-07-02 11:33                                                 ` Paolo Bonzini
2014-07-02 14:00                                                   ` Konrad Rzeszutek Wilk
2014-07-02 14:07                                                     ` Stefano Stabellini
2014-07-03  3:00                                                       ` Chen, Tiejun
2014-07-03 18:25                                                         ` Konrad Rzeszutek Wilk
2014-07-02 14:08                                                     ` Michael S. Tsirkin
2014-07-02 16:05                                                       ` Konrad Rzeszutek Wilk
2014-07-02 17:58                                                         ` Michael S. Tsirkin
2014-07-02 14:50                                                     ` [Qemu-devel] ResettRe: " Paolo Bonzini
2014-07-02 15:12                                                       ` Michael S. Tsirkin
2014-07-02 19:33                                                         ` Alex Williamson
2014-07-02 16:23                                                       ` Konrad Rzeszutek Wilk
2014-07-02 16:27                                                         ` Paolo Bonzini
2014-07-02 16:53                                                         ` Michael S. Tsirkin
2014-07-03  7:32                                                         ` Michael S. Tsirkin
2014-07-03 18:26                                                           ` Konrad Rzeszutek Wilk
2014-07-03 19:09                                                             ` [Qemu-devel] [Intel-gfx] " Jesse Barnes
2014-07-03 20:27                                                               ` Michael S. Tsirkin
2014-07-16 14:20                                                                 ` Konrad Rzeszutek Wilk
2014-07-17  9:42                                                                   ` Chen, Tiejun
2014-07-17 17:37                                                                 ` Kay, Allen M
2014-07-18 13:44                                                                   ` Konrad Rzeszutek Wilk
2014-07-19  0:27                                                                     ` Kay, Allen M
2014-07-23 20:54                                                                       ` Konrad Rzeszutek Wilk
2014-07-24  1:44                                                                         ` Chen, Tiejun
2014-07-25 17:01                                                                           ` Konrad Rzeszutek Wilk
2014-07-29  6:59                                                                             ` Chen, Tiejun
2014-07-29  8:32                                                                               ` Paolo Bonzini
2014-07-29  9:14                                                                                 ` Chen, Tiejun
2014-07-04  6:28                                                               ` [Qemu-devel] " Paolo Bonzini
2014-07-06  6:08                                                                 ` Michael S. Tsirkin
2014-07-02 15:15                                                   ` [Qemu-devel] " Ross Philipson
2014-07-02 15:27                                                     ` Michael S. Tsirkin
2014-07-02 16:29                                                       ` Paolo Bonzini
2014-07-02 16:45                                                         ` Konrad Rzeszutek Wilk
2014-07-02 18:00                                                         ` Michael S. Tsirkin
2014-07-03  5:57                                                       ` Chen, Tiejun
2014-07-03  6:40                                                         ` Michael S. Tsirkin
2014-07-01 18:20                                               ` Stefano Stabellini
2014-07-01 18:38                                                 ` Michael S. Tsirkin
2014-07-02  1:37                                                 ` Chen, Tiejun
2014-07-02  6:09                                                   ` Michael S. Tsirkin
2014-07-02  7:51                                                     ` Chen, Tiejun
2014-06-25  9:55                       ` [Qemu-devel] " Michael S. Tsirkin
2014-06-25  9:59                         ` Paolo Bonzini
2014-06-25 10:06                           ` Chen, Tiejun
2014-06-25 10:21                             ` Michael S. Tsirkin
2014-06-25 10:28                               ` Chen, Tiejun
2014-06-25 10:32                                 ` Michael S. Tsirkin
2014-06-25 10:37                                   ` Chen, Tiejun
2014-06-25 10:55                                     ` Michael S. Tsirkin
2014-06-25 12:11                               ` Paolo Bonzini
2014-06-25 13:47                                 ` Michael S. Tsirkin
2014-06-25 13:53                                   ` Paolo Bonzini
2014-06-25 14:10                                     ` Michael S. Tsirkin
2014-06-25 14:16                                       ` Paolo Bonzini
2014-06-25 14:26                                         ` Michael S. Tsirkin
2014-06-25 10:09                           ` Michael S. Tsirkin
2014-06-25 10:14                             ` Paolo Bonzini
2014-06-25 10:15                             ` Chen, Tiejun
2014-06-25 10:28                               ` Michael S. Tsirkin
2014-06-25  9:43                   ` Michael S. Tsirkin
2014-07-08 10:45 ` [Qemu-devel] [Xen-devel] " Andrew Barnes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=53AA8404.8040708@intel.com \
    --to=tiejun.chen@intel.com \
    --cc=Kelly.Zytaruk@amd.com \
    --cc=allen.m.kay@intel.com \
    --cc=anthony.perard@citrix.com \
    --cc=anthony@codemonkey.ws \
    --cc=mst@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.org \
    --cc=stefano.stabellini@eu.citrix.com \
    --cc=xen-devel@lists.xensource.com \
    --cc=yang.z.zhang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).