Re: [PATCH V2 11/23] arm64, pci: Remove useless boot time IRQ assignment when booting with DT.

[Tomasz Nowicki]

On 12.01.2016 18:56, David Daney wrote:
> On 01/12/2016 08:13 AM, Tomasz Nowicki wrote:
> > On 12.01.2016 14:50, Lorenzo Pieralisi wrote:
> > > On Wed, Dec 16, 2015 at 04:16:21PM +0100, Tomasz Nowicki wrote:
> > > > In order to probe PCIe host controller when booting with DT,
> > > > ARM64 is using drivers which defer IRQ assignment to device
> > > > enable time. It means that boot time DT specific irq map initialization
> > > > is always overridden, so lets remove that code.
> > > >
> > > > Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx>
> > > > ---
> > > >   arch/arm64/kernel/pci.c | 10 ----------
> > > >   1 file changed, 10 deletions(-)
> > > >
> > > > diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
> > > > index 023b983..f7948f5 100644
> > > > --- a/arch/arm64/kernel/pci.c
> > > > +++ b/arch/arm64/kernel/pci.c
> > > > @@ -51,16 +51,6 @@ int pcibios_enable_device(struct pci_dev *dev, int
> > > > mask)
> > > >       return pci_enable_resources(dev, mask);
> > > >   }
> > > >
> > > > -/*
> > > > - * Try to assign the IRQ number from DT when adding a new device
> > > > - */
> > > > -int pcibios_add_device(struct pci_dev *dev)
> > > > -{
> > > > -    dev->irq = of_irq_parse_and_map_pci(dev, 0, 0);
> > > > -
> > > > -    return 0;
> > > > -}
> > > > -
>
> How was this tested?  Or in other words, what PCI devices that use
> legacy INT{A,B,C,D} interrupts were used in testing this patch?

I used QEMU and e1000 NIC:

sudo ./qemu/aarch64-softmmu/qemu-system-aarch64 -smp 1 -m 1024 -M virt 
-cpu cortex-a57 -nographic -device 
e1000,netdev=net1,mac=52:54:00:12:34:56 -netdev 
type=tap,ifname=tun1,id=net1,script=no,downscript=no -drive 
file=qemu/ubuntu.img,id=root,if=none,format=raw -device 
virtio-blk-device,drive=root -kernel linux-aarch64/arch/arm64/boot/Image 
-append "console=ttyAMA0 earlycon=pl011,0x9000000 rw root=/dev/vda"

root@ubuntu:~# ifconfig
eth0      Link encap:Ethernet  HWaddr 52:54:00:12:34:56
          inet addr:10.0.0.48  Bcast:10.0.255.255  Mask:255.255.0.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:107 errors:0 dropped:0 overruns:0 frame:0
          TX packets:32 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:18087 (18.0 KB)  TX bytes:3818 (3.8 KB)

root@ubuntu:~# cat /proc/interrupts
           CPU0
 39:        280       GIC  36 Level     eth0

root@ubuntu:~# lspci -vvv
00:00.0 Host bridge: Red Hat, Inc. Device 0008
        Subsystem: Red Hat, Inc Device 1100
        Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- 
ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- 
<TAbort- <MAbort- >SERR- <PERR- INTx-

00:01.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet 
Controller (rev 03)
        Subsystem: Red Hat, Inc QEMU Virtual Machine
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- 
<TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Interrupt: pin A routed to IRQ 39
        Region 0: Memory at 10040000 (32-bit, non-prefetchable) [size=128K]
        Region 1: I/O ports at 1000 [size=64]
        [virtual] Expansion ROM at 10000000 [disabled] [size=256K]
        Kernel driver in use: e1000

Any specific concern w.r.t. this patch?

Tomasz