SystemACE driver problem

[Grant Likely]

On 10/19/07, aauer1 <aauer1 at gmx.at> wrote:
>
>
>
> Grant Likely-2 wrote:
> >
> > On 10/19/07, aauer1 <aauer1 at gmx.at> wrote:
> >>
> >> Hello
> >>
> >> I'm trying to boot a Linux Kernel 2.6.23-rc2 from Grant Likely (thanks
> >> for
> >> the great work) on a Xilinx ML403 board. I want to use the second
> >> partition
> >> of the Compact Flash Card as root filesystem. But the boot process hangs
> >> at
> >> the initialization of the SystemACE module. A strange effect is that the
> >> DONE LED (configuration of the FPGA is done) turns off. So, this means
> >> that
> >> the FPGA loses his configuration.
> >> Has anybody recognized a similar problem with the SystemACE module??
> >>
> >> The boot log:
> >> ========
> > [snipped]
> >> [    0.268807] uartlite.0: ttyUL0 at MMIO 0x40600000 (irq = 2) is a
> >> uartlite
> >> [    0.270399] console [ttyUL0] enabled
> >> [    1.762725] RAMDISK driver initialized: 8 RAM disks of 8192K size 1024
> >> blocke
> >> [    1.852062] Registering Xilinx SystemACE driver, major=254
> >> [    1.919734] xsysace xsysace.0: ace_probe(c01638e0)
> >
> > Yes, I've seen that.  It means something went wrong with the setup and
> > caused the sysace to reload the FPGA.  Is the systemace base address
> > and bus width set correctly?
> >
> >
>
> The base address is the same as in the system.mhs file of my hardware
> design. So, I think it should be correct. The bus width is set to 16 bits
> (hardware design). So far as I can see, the sysace driver defines a 16 bit
> data bus (hard coded), too.

Hmmm; that's all very odd.  I don't know what could be causing that.

> A paper of BlueCat Linux says that there is a problem with the System ACE
> hardware module:
> "Due to a known problem of the opb_sysace IP Core programmed into the FPGA
> (incorrect operation in the interrupt mode) the SystemACE Compact Flash
> device is supported in the polling mode."
>
> Does anyone know something about the bug in the SystemACE IP core??

I don't know about the old xilinx supplied sysace driver, but the new
xsysace.c driver is robust enough to work around missed interrupts.  I
don't know of any other problems with the opb_sysace IP core.

Cheers,
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely at secretlab.ca
(403) 399-0195