qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [V6 4/4] hw/pci-host: Emulate AMD IOMMU


From: David Kiarie
Subject: Re: [Qemu-devel] [V6 4/4] hw/pci-host: Emulate AMD IOMMU
Date: Thu, 3 Mar 2016 15:18:18 +0300

On Thu, Mar 3, 2016 at 3:06 PM, Marcel Apfelbaum <address@hidden> wrote:
> On 03/03/2016 02:02 PM, Marcel Apfelbaum wrote:
>>
>> On 03/03/2016 01:47 PM, David Kiarie wrote:
>>>
>>> On Thu, Mar 3, 2016 at 12:49 PM, Michael S. Tsirkin <address@hidden>
>>> wrote:
>>>>
>>>> On Thu, Mar 03, 2016 at 01:04:31AM +0300, David Kiarie wrote:
>>>>>
>>>>> On Thu, Mar 3, 2016 at 12:17 AM, Michael S. Tsirkin <address@hidden>
>>>>> wrote:
>>>>>>
>>>>>> On Thu, Mar 03, 2016 at 12:09:28AM +0300, David Kiarie wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 22/02/16 14:22, Marcel Apfelbaum wrote:
>>>>>>>>
>>>>>>>> On 02/21/2016 08:11 PM, David Kiarie wrote:
>>>>>>>>>
>>>>>>>>> Add AMD IOMMU emulation support to q35 chipset
>>>>>>>>>
>>>>>>>>> Signed-off-by: David Kiarie <address@hidden>
>>>>>>>>> ---
>>>>>>>>>   hw/pci-host/piix.c            |  1 +
>>>>>>>>>   hw/pci-host/q35.c             | 14 ++++++++++++--
>>>>>>>>>   include/hw/i386/intel_iommu.h |  1 +
>>>>>>>>>   3 files changed, 14 insertions(+), 2 deletions(-)
>>>>>>>>>
>>>>>>>>> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
>>>>>>>>> index 41aa66f..ab2e24a 100644
>>>>>>>>> --- a/hw/pci-host/piix.c
>>>>>>>>> +++ b/hw/pci-host/piix.c
>>>>>>>>> @@ -36,6 +36,7 @@
>>>>>>>>>   #include "hw/i386/ioapic.h"
>>>>>>>>>   #include "qapi/visitor.h"
>>>>>>>>>   #include "qemu/error-report.h"
>>>>>>>>> +#include "hw/i386/amd_iommu.h"
>>>>>>>>
>>>>>>>>
>>>>>>>> Hi,
>>>>>>>>
>>>>>>>> I think you don't need this include anymore.
>>>>>>>>
>>>>>>>>>
>>>>>>>>>   /*
>>>>>>>>>    * I440FX chipset data sheet.
>>>>>>>>> diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
>>>>>>>>> index 115fb8c..355fb32 100644
>>>>>>>>> --- a/hw/pci-host/q35.c
>>>>>>>>> +++ b/hw/pci-host/q35.c
>>>>>>>>> @@ -31,6 +31,7 @@
>>>>>>>>>   #include "hw/hw.h"
>>>>>>>>>   #include "hw/pci-host/q35.h"
>>>>>>>>>   #include "qapi/visitor.h"
>>>>>>>>> +#include "hw/i386/amd_iommu.h"
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> /****************************************************************************
>>>>>>>>>    * Q35 host
>>>>>>>>> @@ -505,9 +506,18 @@ static void mch_realize(PCIDevice *d, Error
>>>>>>>>> **errp)
>>>>>>>>>                    mch->pci_address_space, &mch->pam_regions[i+1],
>>>>>>>>>                    PAM_EXPAN_BASE + i * PAM_EXPAN_SIZE,
>>>>>>>>> PAM_EXPAN_SIZE);
>>>>>>>>>       }
>>>>>>>>> -    /* Intel IOMMU (VT-d) */
>>>>>>>>> -    if (object_property_get_bool(qdev_get_machine(), "iommu",
>>>>>>>>> NULL)) {
>>>>>>>>> +
>>>>>>>>> +    if (g_strcmp0(MACHINE(qdev_get_machine())->iommu,
>>>>>>>>> INTEL_IOMMU_STR)
>>>>>>>>> == 0) {
>>>>>>>>> +        /* Intel IOMMU (VT-d) */
>>>>>>>>>           mch_init_dmar(mch);
>>>>>>>>> +    } else if (g_strcmp0(MACHINE(qdev_get_machine())->iommu,
>>>>>>>>> AMD_IOMMU_STR)
>>>>>>>>> +               == 0) {
>>>>>>>>> +        AMDIOMMUState *iommu_state;
>>>>>>>>> +        PCIDevice *iommu;
>>>>>>>>> +        PCIBus *bus = PCI_BUS(qdev_get_parent_bus(DEVICE(mch)));
>>>>>>>>> +        iommu = pci_create_simple(bus, 0x20,
>>>>>>>>> TYPE_AMD_IOMMU_DEVICE);
>>>>>>
>>>>>>
>>>>>> Pls don't hardcode paths like this. Set addr property instead.
>>>>>>
>>>>>>>>> +        iommu_state = AMD_IOMMU_DEVICE(iommu);
>>>>>>>>> +        pci_setup_iommu(bus, bridge_host_amd_iommu, iommu_state);
>>>>>>>>
>>>>>>>>
>>>>>>>> pci_setup_iommu third parameter is void*, so you don't need to cast
>>>>>>>> to
>>>>>>>> AMDIOMMUState
>>>>>>>> before passing it.
>>>>>>>
>>>>>>>
>>>>>>> This include is necessary for the definition of "AMD_IOMMU_STR"
>>>>>>> either way
>>>>>>> so am leaving this as is.
>>>>>>
>>>>>>
>>>>>> This option parsing is just too ugly.
>>>>>>
>>>>>> Looks like it was a mistake to support the iommu
>>>>>> machine property, but I see no reason to add to the
>>>>>> existing mess.
>>>>>>
>>>>>> Can't users create iommu with -device amd-iommu ?
>>>>>
>>>>>
>>>>> You mean getting rid of the above code and starting device with
>>>>> '-device amd-iommu' ? This way am not able to setup IOMMU regions for
>>>>> devices correctly. IIRC 'pci_setup_iommu' when called from IOMMU code
>>>>> sets up IOMMU region for IOMMU only. Calling this from the bus sets up
>>>>> IOMMU regions for all devices though.
>>>>>
>>>>> I need to setup IOMMU regions for all devices from the bus, to be able
>>>>> to do that I need to have created the IOMMU device first.
>>>>
>>>>
>>>> I agree it's unfortunate, but I don't think internal limitations
>>>> should affect the user interface like this.
>>>>
>>>> I wish we had a way to specify initialization order for devices in some
>>>> way, such that system devices are created before others.
>>>>
>>>> For now, can you call pci_setup_iommu in the machine done callback?
>>>>
>>>>>>
>>>>>> It's necessary if we are to support multiple IOMMUs, anyway.
>>>
>>>
>>> If this is mainly to allow users run multiple IOMMUs I think the
>>> greatest limitation is that Qemu only have one PCI bus which can only
>>> host one IOMMU, AFAIK so unless there are huge structural changes
>>> running multiple IOMMU on Qemu may not be possible.
>>
>>
>> Actually we have good news on this front.
>> You can use as many pxb-pcie devices as you want to create extra PCI root
>> buses.
>> Assigning them different IOMMUs would be great. (long term, of course)
>>
>
> Even without pxb-pcie, you can add a pci-bridge to expose a secondary PCI
> bus
> and limit IOMMU scope to that PCI bridge.

Hmmh, good to know. Will look at that.

>
> Thanks,
> Marcel
>
>
>>
>> Thanks,
>> Marcel
>>
>>>
>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Marcel
>>>>>>>>
>>>>>>>>>       }
>>>>>>>>>   }
>>>>>>>>>
>>>>>>>>> diff --git a/include/hw/i386/intel_iommu.h
>>>>>>>>> b/include/hw/i386/intel_iommu.h
>>>>>>>>> index b024ffa..539530c 100644
>>>>>>>>> --- a/include/hw/i386/intel_iommu.h
>>>>>>>>> +++ b/include/hw/i386/intel_iommu.h
>>>>>>>>> @@ -27,6 +27,7 @@
>>>>>>>>>   #define TYPE_INTEL_IOMMU_DEVICE "intel-iommu"
>>>>>>>>>   #define INTEL_IOMMU_DEVICE(obj) \
>>>>>>>>>        OBJECT_CHECK(IntelIOMMUState, (obj),
>>>>>>>>> TYPE_INTEL_IOMMU_DEVICE)
>>>>>>>>> +#define INTEL_IOMMU_STR "intel"
>>>>>>>>>
>>>>>>>>>   /* DMAR Hardware Unit Definition address (IOMMU unit) */
>>>>>>>>>   #define Q35_HOST_BRIDGE_IOMMU_ADDR  0xfed90000ULL
>>>>>>>>>
>>>>>>>>
>>
>



reply via email to

[Prev in Thread] Current Thread [Next in Thread]