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

[Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>]

On 03/12/2019 08:25, Thomas Huth wrote:

> On 03/12/2019 08.45, Philippe Mathieu-Daudé wrote:
>> On 12/3/19 8:29 AM, Thomas Huth wrote:
>>> It's been deprecated since QEMU v3.1. The 40p machine should be
>>> used nowadays instead.
>>>
>>> Signed-off-by: Thomas Huth <thuth@redhat.com>
>>> ---
>>>   .gitmodules                |   3 -
>>>   MAINTAINERS                |   1 -
>>>   Makefile                   |   2 +-
>>>   docs/interop/firmware.json |   3 +-
>>>   hw/ppc/ppc.c               |  18 --
>>>   hw/ppc/prep.c              | 384 +------------------------------------
>>>   include/hw/ppc/ppc.h       |   1 -
>>>   pc-bios/README             |   3 -
>>>   pc-bios/ppc_rom.bin        | Bin 1048576 -> 0 bytes
>>>   qemu-deprecated.texi       |   6 -
>>>   qemu-doc.texi              |  15 +-
>>>   roms/openhackware          |   1 -
>>>   tests/boot-order-test.c    |  25 ---
>>>   tests/cdrom-test.c         |   2 +-
>>>   tests/endianness-test.c    |   2 +-
>>>   15 files changed, 10 insertions(+), 456 deletions(-)
>>>   delete mode 100644 pc-bios/ppc_rom.bin
>>>   delete mode 160000 roms/openhackware
>> [...]
>>> diff --git a/tests/boot-order-test.c b/tests/boot-order-test.c
>>> index a725bce729..4a6218a516 100644
>>> --- a/tests/boot-order-test.c
>>> +++ b/tests/boot-order-test.c
>>> @@ -108,30 +108,6 @@ static void test_pc_boot_order(void)
>>>       test_boot_orders(NULL, read_boot_order_pc, test_cases_pc);
>>>   }
>>>   -static uint8_t read_m48t59(QTestState *qts, uint64_t addr, uint16_t
>>> reg)
>>> -{
>>> -    qtest_writeb(qts, addr, reg & 0xff);
>>> -    qtest_writeb(qts, addr + 1, reg >> 8);
>>> -    return qtest_readb(qts, addr + 3);
>>> -}
>>> -
>>> -static uint64_t read_boot_order_prep(QTestState *qts)
>>> -{
>>> -    return read_m48t59(qts, 0x80000000 + 0x74, 0x34);
>>
>> I'd rather keep this generic mmio-mapped ISA test.
>> Maybe run it with the 40p machine?
> 
> I don't think that this is possible in an easy way here. On the prep
> machine, the ISA bus is on a hard-coded MMIO address. On the 40p
> machine, the ISA bus is behind a PCI-to-ISA bridge, thus the PCI part
> needs to be set up first.

FWIW for sun4u we already cheat a bit here: the ebus device is the first PCI device
behind the PCI bridge which uses IO space, and so we know that this ultimately gets
mapped to the start of the IO memory space. We also configure the PCI bridge in QEMU
so that it allows IO accesses by default which means we also get the early console
before PCI bus enumeration.

>> 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.

From memory there were some issues with fw_cfg because the prep (OHW) and 40p
(OpenBIOS) machines had different NVRAM layouts. Once the prep machine has been
removed it should be easy to fix though.


ATB,

Mark.