Re: Why do we probe option roms at 2K boundaries?

[Hans de Goede <hdegoede@redhat.com>]

Hi all,

On 07/16/2009 02:08 AM, Dan Williams wrote:
> On Wed, 2009-07-15 at 16:13 -0700, Jon Smirl wrote:
>> On Wed, Jul 15, 2009 at 7:10 PM, Alan Cox<alan@lxorguk.ukuu.org.uk>  wrote:
>>>> interrogating a data structure stored in option-rom memory.  My initial
>>>> implementation involved blindly scanning from c0000 to f0000 in 512 byte
>>>> increments.  Neil and others pointed out that this may not be a safe
>>> It isn't safe. If you hit certain ISA devices your system will drop dead.
>>> OTOH I doubt anyone has an intel matrix raid controller and a WD80x3 on
>>> the same box ;)
>> Random link from google, slide 21
>> http://download.microsoft.com/download/9/8/f/98f3fe47-dfc3-4e74-92a3-088782200fe7/TWAR05005_WinHEC05.ppt
>>
>> PCI 3.0+ allows 512b alignment, but you must first make sure you are
>> on a PCI 3.0+ system.
>
> Thanks, I believe this may be the missing difference between my test
> system and Hans'.
>

Probably, I'll happily test any patches for this you come up with, note that I'm
leaving for a week of vacation tomorrow, so it might take some time for me to
get back to you.

Regards,

Hans