Hello all,
On Mon, Dec 1, 2008 at 9:12 AM, Benjamin Herrenschmidt benh@kernel.crashing.org wrote:
On Fri, 2008-11-28 at 13:50 +0100, Leon Woestenberg wrote:
AMCC PPC460EX canyonlands board with an FPGA PCIe end point:
u-boot sees the end point, but Linux does not:
U-Boot 1.3.3-00249-ga524e11 (Jun 30 2008 - 16:05:51) CPU: AMCC PowerPC 460EX Rev. A at 800 MHz (PLB=200, OPB=100, EBC=100 MHz) <...> Board: Canyonlands - AMCC PPC460EX Evaluation Board, 2*PCIe, Rev. 16 <...> PCIE1: successfully set as root-complex 02 00 2071 2071 00ff 00
Now, if I re-program the end-point FPGA during the u-boot boot time-out, Linux will recognize the end-point.
It's possible that either the reset in between goes bonkers or something else causes your FPGA to stop responding. It looks like a programming problem with the FPGA to me.
I have verified that the end point does not receive any kind of reset.
Also, this problem only happens on the Canyonlands board; on x86 and powerpc MPC8315E it remains properly working after soft/hard resets, u-boot init etc.
Could it be u-boot overwrites a too large payload into the config space or something similar, which makes subsequent accesses fail?
Regards,