[PATCH V2 11/23] arm64, pci: Remove useless boot time IRQ assignment when booting with DT.
Tomasz Nowicki
tn at semihalf.com
Wed Jan 13 01:43:07 PST 2016
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 at semihalf.com>
>>>> ---
>>>> 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 at 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 at ubuntu:~# cat /proc/interrupts
CPU0
39: 280 GIC 36 Level eth0
root at 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
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