Re: [PATCH] hw/ppc/prep: Remove the deprecated "prep" machine and the OpenHackware BIOS

[Thomas Huth]

On 03/12/2019 14.04, Paolo Bonzini wrote:
> On 03/12/19 10:15, Thomas Huth wrote:
>>>>> Maybe we can rename this as read_boot_order_mm, and the previous
>>>>> read_boot_order_pc as read_boot_order_io.
>>>>
>>>> I don't think it makes much sense. This was completely specific to the
>>>> "prep" machine, even the "40p" machine seems to prefer fw_cfg nowadays.
>>>> So let's simply remove this old stuff.
>>>>
>>>>> diff --git a/tests/endianness-test.c b/tests/endianness-test.c
>>>>> index 58527952a5..2798802c63 100644
>>>>> --- a/tests/endianness-test.c
>>>>> +++ b/tests/endianness-test.c
>>>>> @@ -35,7 +35,7 @@ static const TestCase test_cases[] = {
>>>>>        { "mips64", "malta", 0x10000000, .bswap = true },
>>>>>        { "mips64el", "fulong2e", 0x1fd00000 },
>>>>>        { "ppc", "g3beige", 0xfe000000, .bswap = true, .superio =
>>>>> "i82378" },
>>>>> -    { "ppc", "prep", 0x80000000, .bswap = true },
>>>>> +    { "ppc", "40p", 0x80000000, .bswap = true },
>>>
>>> ... here you access the Super I/O behind the PCI bridge via MMIO?
>>
>> The difference is that this is an *arbitrary* address in I/O space
>> there.
> 
> No, it's the base address of the ISA space, to which the tests add the
> address of the pc-testdev device.  It's not any different from the
> 0x80000000 in boot-order-test.

Hmm, interesting. Why is it not necessary to set up the BARs of the
PCI-to-ISA bridge in this case?

> That said, I think it's a sensible objection that boot order doesn't
> come from m48t59 on 40p (does it not?).
Right. I'm also not an expert here, but I think the OpenBIOS on 40p
rather uses fw_cfg instead.

 Thomas