[coreboot] unexpected exception errors loading vga rom

Joseph Smith joe at settoplinux.org
Fri May 1 02:43:49 CEST 2009

On Thu, 30 Apr 2009 14:55:59 -0700, ron minnich <rminnich at gmail.com> wrote:
> On Thu, Apr 30, 2009 at 2:01 PM, Joseph Smith <joe at settoplinux.org>
>> Right the INT lines A,B,C, and D are hard wired. But you can asign any
>> to a function and any available IRQ to the PIRQ these are software
>> controlled.
> The 3d register lists what functions can assert what interrupt lines.
> what is the value of 3d for each of these four device functions? You
> can use setpci to see.
> setpci -s bus:dev.fn 3d.b
>> Hmm. That is another way of looking at it. The doc does say the "device"
>> acts as a interrupt router (which is INTA in this case). So the other
> three
>> are directly connected to it? Like the attached image?
> I doubt that is exactly it but I think it's closer to my internal
> picture. 
I wish you could make your internal picture external, so I could see what
it is then.
So to test this I theory I should just be able to pluck out oh lets say
function 2 on INTB. If everythings works great except USB2 than that theory
is correct. On the otherhand if we loose USB2, USB3, and EHCI than we know
they are routed through each other. Correct?
Like this:
{0x00,(0x1d<<3)|0x0, {{0x60, 0x1ef8}, {0x00, 0x00000}, {0x62, 0x1ef8},
{0x6b, 0x01ef8}}, 0x0, 0x0},

> What the 3d register will tell you is what INT is wired to
> each function. So, e.g., I would guest that 3d is like this:
> USB1 1
> USB2 2
> USB3 3
> EHCI 4
00:1d.0 USB Controller #1 - 0x3d = 0x01
00:1d.1 USB Controller #2 - 0x3d = 0x02
00:1d.2 USB Controller #3 - 0x3d = 0x03
00:1d.7 USB Controller EHCI - 0x3d = 0x04

Joseph Smith

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