[Nouveau] [PATCH] bios: fix OF loading

[Ilia Mirkin]

On Fri, Oct 2, 2015 at 3:39 AM, Hans de Goede <hdegoede at redhat.com> wrote:
> Hi,
>
>
> On 02-10-15 09:38, Ilia Mirkin wrote:
>>
>> On Fri, Oct 2, 2015 at 3:35 AM, Hans de Goede <hdegoede at redhat.com> wrote:
>>>
>>> Hi,
>>>
>>> On 02-10-15 09:26, Ilia Mirkin wrote:
>>>>
>>>>
>>>> On Fri, Oct 2, 2015 at 3:18 AM, Hans de Goede <hdegoede at redhat.com>
>>>> wrote:
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>> On 02-10-15 05:41, Ilia Mirkin wrote:
>>>>>
>>>>> <nothing>
>>>>>
>>>>> As someone who has recently started following nouveau I must say that
>>>>> it would greatly help me (and likely others) if patches likes this
>>>>> would
>>>>> come with a somewhat more descriptive commit message.
>>>>
>>>>
>>>>
>>>> Duly noted. I normally try to say a bit, but have gotten lazy of late.
>>>> Ben's pretty terse too :) How about something like
>>>>
>>>> """
>>>> Currently OF bios load fails for a few reasons:
>>>>    - checksum failure
>>>>    - bios size too small
>>>>    - no PCIR header
>>>>    - bios length not a multiple of 4
>>>>
>>>> In this change, we resolve all of the above by ignoring any checksum
>>>> failures, and faking the PCIR data when loading from OF.
>>>> """
>>>
>>>
>>>
>>> Much better, I must say that now that you spell it out that the
>>> ignoring of the checksum sort of worries me, but I guess the
>>> checksum is part of the missing PCIR header ?
>>
>>
>> Nope, the two things are unrelated. The PCIR section is normally
>> embedded in the vbios and tells you how long the vbios is, and allows
>> you to have multiple elements appended at the end (which nouveau has
>> recently acquired some support for). The checksum failures just
>> happen,
>
>
>> "pretty sure that the OF-sourced vbioses just don't have a
>>  checksum byte at all."
>
>
> You may want to add something along those lines to the commit message
> too...

Ben, I see you already committed my change to your tree, could you
amend the commit message to read something like

"""
Currently OF bios load fails for a few reasons:
 - checksum failure
 - bios size too small
 - no PCIR header
 - bios length not a multiple of 4

In this change, we resolve all of the above by ignoring any checksum
failures (since OF VBIOS tends not to have a checksum), and faking the
PCIR data when loading from OF.
"""

I think Hans has a very valid point about the terseness of nouveau
commit messages... I'm often a bit annoyed at the terseness of yours
esp for larger changes, but apparently I go and do the same thing
myself :)

Thanks,

  -ilia