hi!

i've recently had a similar situation with a XC2VP50-based custom board.
There was no SystemACE involved, we load the FPGA via a CPLD/serial flash.

the problem resided in the interrupt controller, which was not able to enable 
interrupts due to an error in the MHS file.
you should check that your interrupt controller section includes the following 
parameters:
PARAMETER C_HAS_IPR = 1
PARAMETER C_HAS_SIE = 1
PARAMETER C_HAS_CIE = 1
PARAMETER C_HAS_IVR = 1

the intc driver uses SIE and CIE to atomically enable and disable interrupts.
when the uartlite interrupt was not enabled, the uartlite driver encountered 
timeouts which caused single characters to appear at the serial console, 
similar to what you described.

hope that helps,
arvid staub


________________________________________
Von: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Im Auftrag von Clint Thomas
Gesendet: Montag, 28. August 2006 21:57
An: [email protected]
Betreff: PPC405 system slow boot

Hey guys,

I've run through the loops to try and figure what could be wrong with this 
system. The board in question is modeled after the Xilinx ML300 board. It uses 
a Xilinx System ACE chip to load a FPGA / Kernel image from compact flash. 
Originally, I was trying to use the CompactFlash as the root file system, but 
because of issues in either the design or software, this would only work if 
SysAce was in polled I/O mode. To circumvent this, I built my root filesystem 
into an initrd image and built a single ELF file with the Kernel and RFS, then 
strapped that to the FPGA bit file to make a single FPGA/Kernel/RFS SysAce file.

Upon decompression, the Linux kernel boots quickly and loads all of the device 
drivers. However when it gets to the prompt, it starts slowing down. Output and 
input to and from the board becomes very very slow (it displays 2 characters 
roughly every 20 seconds). Originally I believed this to be the CPU still 
polling SystemAce, so I disabled the Linux System ACE drivers to remove that as 
a possibility, however after doing this, the problem still persists, even with 
the RFS in ram! Has anybody encountered a similar situation to this before, 
with possible insight towards a solution? Thank you for your time.
 
Clinton Thomas
[EMAIL PROTECTED]
 
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