SB700 IMC disabling

[Carl-Daniel Hailfinger]

Hi Zheng,

running flashrom on certain systems with SB700 family chipsets will
result in read and write corruption. I have added a corruption check to
latest flashrom, and it seems that the IMC will access flash even if
flashrom holds the BiosSemaphore (LPC bridge config space register 0x40,
bit 5).

Matthias Kretz owns a Supermicro H8DGT with this problem, but other
boards (including a MITAC development board) exhibit the same issue.
If we use flashrom to write, the SPI registers (especially FIFO counter
and FIFO) will lock up after some time, and we have not been successful
in getting the stuck board working again.

Is there a way to stop the IMC from the host or to stop all IMC flash
accesses (including read and instruction fetch)?

Regards,
Carl-Daniel

[Bao, Zheng]

Sorry, I don't have any idea about imc accessing.

Zheng
> -----Original Message-----
> From: Carl-Daniel Hailfinger

[mailto:[e-mail]]
> Sent: Thursday, August 19, 2010 6:10 PM
> To: flashrom; Bao, Zheng; Matthias Kretz
> Subject: [flashrom] SB700 IMC disabling
>
> Hi Zheng,
>
> running flashrom on certain systems with SB700 family chipsets will
> result in read and write corruption. I have added a corruption check

to
> latest flashrom, and it seems that the IMC will access flash even if
> flashrom holds the BiosSemaphore (LPC bridge config space register

0x40,
> bit 5).
>
> Matthias Kretz owns a Supermicro H8DGT with this problem, but other
> boards (including a MITAC development board) exhibit the same issue.
> If we use flashrom to write, the SPI registers (especially FIFO

counter
> and FIFO) will lock up after some time, and we have not been

successful
> in getting the stuck board working again.
>
> Is there a way to stop the IMC from the host or to stop all IMC flash
> accesses (including read and instruction fetch)?
>
> Regards,
> Carl-Daniel

[Carl-Daniel Hailfinger]

Hi Zheng,

do you know anyone at AMD who could help us with those IMC problems or
at least tell us how to stop the IMC?

Regards,
Carl-Daniel

On 19.08.2010 12:23, Bao, Zheng wrote:
> Sorry, I don't have any idea about imc accessing.
>
> Zheng
> > -----Original Message-----
> > From: Carl-Daniel Hailfinger
> > [mailto:[e-mail]]
> > Sent: Thursday, August 19, 2010 6:10 PM
> > To: flashrom; Bao, Zheng; Matthias Kretz
> > Subject: [flashrom] SB700 IMC disabling
> >
> > Hi Zheng,
> >
> > running flashrom on certain systems with SB700 family chipsets will
> > result in read and write corruption. I have added a corruption check
> > to latest flashrom, and it seems that the IMC will access flash even
> > if flashrom holds the BiosSemaphore (LPC bridge config space register
> > 0x40, bit 5).
> >
> > Matthias Kretz owns a Supermicro H8DGT with this problem, but other
> > boards (including a MITAC development board) exhibit the same issue.
> > If we use flashrom to write, the SPI registers (especially FIFO
> > counter and FIFO) will lock up after some time, and we have not been
> > successful in getting the stuck board working again.
> >
> > Is there a way to stop the IMC from the host or to stop all IMC flash
> > accesses (including read and instruction fetch)?
> >
> > Regards,
> > Carl-Daniel