Re: [EXTERNAL] allocating IRQ mentioned in _CRS of ACPI

Based on my reading of the ACPI tables, and looking how Linux handles it I don’t think the vmbus_res driver should be used. If the vmbus driver was to attach to the “VMBUS" _HID it would be able to manage the interrupt directly.

Ideally acpi_syscontainer would become a proper bus, but that would need checking that existing drivers that depend on the current behaviour still work.

Andrew

> On 19 Oct 2022, at 18:51, Souradeep Chakrabarti <schakrabarti@microsoft.com> wrote:
> 
> Hi Warner,
>  
> 1) PCI mmio resource in HID "ACPI0004", which is needed by the FreeBSD guest for SRIOV devices.
>  
>    Device (\_SB.VMOD)    <-- This is currently owned by acpi_syscontainer module on FreeBSD
>     {
>         Name (_HID, "ACPI0004" /* Module Device */)  // _HID: Hardware ID
>         Name (_UID, Zero)  // _UID: Unique ID
>         Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
>         {
>             ...
>         }
>         CreateDWordField (_CRS, \_SB.VMOD._Y00._MIN, MIN6)  // _MIN: Minimum Base Address
>         CreateDWordField (_CRS, \_SB.VMOD._Y00._MAX, MAX6)  // _MAX: Maximum Base Address
>         CreateDWordField (_CRS, \_SB.VMOD._Y00._LEN, LEN6)  // _LEN: Length
>         CreateQWordField (_CRS, \_SB.VMOD._Y01._MIN, MIN7)  // _MIN: Minimum Base Address
>         CreateQWordField (_CRS, \_SB.VMOD._Y01._MAX, MAX7)  // _MAX: Maximum Base Address
>         CreateQWordField (_CRS, \_SB.VMOD._Y01._LEN, LEN7)  // _LEN: Length
>         Method (_INI, 0, NotSerialized)  // _INI: Initialize
>         {
>             MIN6 = MG2B /* \MG2B */
>             LEN6 = MG2L /* \MG2L */
>             Local0 = MG2L /* \MG2L */
>             MAX6 = (MIN6 + Local0--)
>             Local1 = (HMIB << 0x14)
>             Local2 = (HMIL << 0x14)
>             MIN7 = Local1
>             LEN7 = Local2
>             Local0 = Local2
>             MAX7 = (MIN7 + Local0--)
>         }
>     }
>  
> 2) Vmbus IRQ resource in HID "VMBus", which is needed to get Hyper-V vmbus interrupt to work on guests.
> Device (\_SB.VMOD.VMBS)   <--- currently owned by vmbus_res module on FreeBSD
>     {
>         ...
>         Name (_HID, "VMBus")  // _HID: Hardware ID
>         Name (_UID, Zero)  // _UID: Unique ID
>         ...
>         Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
>         {
>             Interrupt (ResourceConsumer, Edge, ActiveHigh, Exclusive, ,, )
>             {
>                 0x00000012,
>             }
>         })
>     }
>  
> <image001.png>
>  
> Today I was able to get both IRQ and MMIO allocation successful using below snippet in vmbus:
>  
> +       device_t dev =  devclass_get_device(devclass_find("vmbus_res"), 0);
> +       sc->ires = bus_alloc_resource_any(dev,
>             SYS_RES_IRQ, &sc->vector, RF_ACTIVE | RF_SHAREABLE);
>  
>  
> Thanks & Regards,
>  Souradeep
>  
> From: Warner Losh <imp@bsdimp.com> 
> Sent: Wednesday, October 19, 2022 11:09 PM
> To: Souradeep Chakrabarti <schakrabarti@microsoft.com>
> Cc: freebsd-hackers@freebsd.org; Wei Hu <weh@microsoft.com>
> Subject: [EXTERNAL] Re: allocating IRQ mentioned in _CRS of ACPI
>  
> Sorry for the late reply... I've been busy with some things for work...
>  
> I think you'll need to get the parent of vmbus to allow a pass through allocation. What bus is that
> currently?
>  
> Warner
>  
> On Tue, Oct 18, 2022 at 12:33 PM Souradeep Chakrabarti <schakrabarti@microsoft.com <mailto:schakrabarti@microsoft.com>> wrote:
> Hi,
> It will be a great help, if someone can help here with some idea.
> As it is blocking the FreeBSD on Hyper-V ARM64.
> 
> Thanks & Regards,
> Souradeep
> 
> > -----Original Message-----
> > From: Souradeep Chakrabarti
> > Sent: Friday, October 14, 2022 1:24 PM
> > To: 'Warner Losh' <imp@bsdimp.com <mailto:imp@bsdimp.com>>
> > Cc: freebsd-hackers@freebsd.org <mailto:freebsd-hackers@freebsd.org>; Wei Hu <weh@microsoft.com <mailto:weh@microsoft.com>>
> > Subject: RE: allocating IRQ mentioned in _CRS of ACPI
> > 
> > Last mail was having incorrect FreeBSD hacker alias. Replacing that with correct
> > one here.
> > 
> > 
> > > -----Original Message-----
> > > From: Souradeep Chakrabarti
> > > Sent: Friday, October 14, 2022 1:19 PM
> > > To: Warner Losh <imp@bsdimp.com <mailto:imp@bsdimp.com>>
> > > Cc: hacker@freebsd.org <mailto:hacker@freebsd.org>; Wei Hu <weh@microsoft.com <mailto:weh@microsoft.com>>
> > > Subject: allocating IRQ mentioned in _CRS of ACPI
> > >
> > > Hi,
> > > I would like to allocate IRQ to a device, mentioned in the _CRS of
> > > that device in ACPI table.
> > > I have tried with bus_alloc_resource_any(), but it is failing as the
> > > parent of that device is not owning the IRQ.
> > >
> > > Current ACPI topo for the device :
> > > ACPI0->SB.VMOD(HID ACPI0004, has SYS_RES_MEM for MMIO in _CRS)-
> > > >VMBUS( it has SYS_RES_IRQ in it's _CRS).
> > >
> > > How can I get here both SYS_RES_IRQ and SYS_RES_MEM allocated to VMBUS?
> > >
> > > Thanks & Regards,
> > > Souradeep