On 10/11/07, robert lazarski robertlazarski@gmail.com wrote:
Hi all,
We've been stuck for about 3 weeks trying to run u-boot on our custom 8548 board. Its failing in the generic start.S code, independent of what TLB's we have. We've tracked this down to be hardware, but after much head scratching and many official support contacts, we are without any solid theories on the cause.
We found the cause, which I'm posting here in case it helps somebody someday. The type of problem pointed to the CCB, and sure enough both the sysclk and CCB clock were too low.
We had:
SYSCLK : 7.63 MHZ CCB Frequency: 20 x SYSCLK = 152MHZ E500 Frequency: 5:2 x CCB Frequency = 381.5 MHZ
That's all too low. We can at least mount the TLB's with:
SYSCLK: 17.77 MHZ CCB Frequency : 20 x 17.77 -> 355.4 MHZ E500 Frequency: 5/2 x CCB -> 2.5 x 355.4 -> 888.5 MHZ
Robert