[OpenBIOS] [PATCH 1/2] 40p: update interrupt routing code to match QEMU

[Hervé Poussineau]

Le 03/10/2018 à 17:49, Mark Cave-Ayland a écrit :
> On 01/10/2018 20:27, Mark Cave-Ayland wrote:
> 
>> On 01/10/2018 20:20, Hervé Poussineau wrote:
>>
>>> Le 01/10/2018 à 19:55, Mark Cave-Ayland a écrit :
>>>> Note that whilst guest OSs should be relying on residual data rather than the
>>>> OF device tree to determine the hardware, we still update the interrupt
>>>> properties to match the new code in QEMU for consistency.
>>>>
>>>> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland at ilande.co.uk>
>>>> ---
>>>>    arch/ppc/qemu/init.c |  2 +-
>>>>    drivers/pci.c        | 24 ++++++++++++++++++++----
>>>>    2 files changed, 21 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/arch/ppc/qemu/init.c b/arch/ppc/qemu/init.c
>>>> index 759f7ac..f72728c 100644
>>>> --- a/arch/ppc/qemu/init.c
>>>> +++ b/arch/ppc/qemu/init.c
>>>> @@ -130,7 +130,7 @@ static const pci_arch_t known_arch[] = {
>>>>                { .type = MEMORY_SPACE_32, .parentaddr = 0, .childaddr = 0xc0100000,
>>>> .len = 0x10000000 },
>>>>                { .type = 0, .parentaddr = 0, .childaddr = 0, .len = 0 }
>>>>             },
>>>> -        .irqs = { 9, 11, 9, 11 }
>>>> +        .irqs = { 15, 15, 15, 15 }
>>>>        },
>>>>        [ARCH_MAC99] = {
>>>>            .name = "MAC99",
>>>> diff --git a/drivers/pci.c b/drivers/pci.c
>>>> index 8f97ae1..92fd4af 100644
>>>> --- a/drivers/pci.c
>>>> +++ b/drivers/pci.c
>>>> @@ -1986,10 +1986,26 @@ static phandle_t ob_pci_host_set_interrupt_map(phandle_t host)
>>>>    static void ob_pci_host_bus_interrupt(ucell dnode, u32 *props, int *ncells, u32
>>>> addr, u32 intno)
>>>>    {
>>>>        *ncells += pci_encode_phys_addr(props + *ncells, 0, 0, addr, 0, 0);
>>>> -    props[(*ncells)++] = intno;
>>>> -    props[(*ncells)++] = dnode;
>>>> -    props[(*ncells)++] = arch->irqs[((intno - 1) + (addr >> 11)) & 3];
>>>> -    props[(*ncells)++] = 1;
>>>> +
>>>> +    if (is_oldworld() || is_newworld()) {
>>>> +        /* Mac machines */
>>>> +        props[(*ncells)++] = intno;
>>>> +        props[(*ncells)++] = dnode;
>>>> +        props[(*ncells)++] = arch->irqs[((intno - 1) + (addr >> 11)) & 3];
>>>> +        props[(*ncells)++] = 1;
>>>> +    } else {
>>>> +        /* PReP machines */
>>>> +        props[(*ncells)++] = intno;
>>>> +        props[(*ncells)++] = dnode;
>>>> +
>>>> +        if (PCI_DEV(addr) == 1 && PCI_FN(addr) == 0) {
>>>> +            /* LSI SCSI has fixed routing to IRQ 13 */
>>>> +            props[(*ncells)++] = 13;
>>>> +        } else {
>>>> +            props[(*ncells)++] = arch->irqs[((intno - 1) + (addr >> 11)) & 1];
>>>
>>> In that case, arch.irqs = { 15, 15, 15, 15 }.
>>> Why doing a "& 1", instead of doing arch->irqs[0], or hard-coding 15?
>>
>> Mainly for consistency so it matches the same algorithm in raven_map_irq() - see
>> https://git.qemu.org/?p=qemu.git;a=blob;f=hw/pci-host/prep.c;h=b1b6b16badb38ff35e4c50f358fdc6aab08f5b51;hb=a2ef4d9e95400cd387ab4ae19a317741e458fb07#l193
>>
>> I was under the impression that this was how it was modelled on real hardware,
>> although I don't personally have any documentation to support this.
> 
> Hi Hervé,
> 
> Even though you had some questions, are you still happy for me to merge this? It
> would be good to get the sandalfoot zImage working in QEMU master :)

Hello,

No objection to merge this to OpenBIOS.

Hervé