Stamp9261

[Daan Vreeken]

Hi all,

I've recently received a Stamp9261 evaluation board [1] and I'm trying to get 
FreeBSD to run on it. As a starting point I've taken -CURRENT as of 
2011-02-10 and created a custom kernel config file with (among others) the 
following :
	files   "../at91/files.at91sam9"
	cpu             CPU_ARM9
	makeoptions     CONF_CFLAGS="-mcpu=arm9"
	options         PHYSADDR=0x20000000
	device          at91sam9260

	options         STARTUP_PAGETABLE_ADDR=0x20800000
	makeoptions     KERNPHYSADDR=0x20000000
	makeoptions     KERNVIRTADDR=0xc0000000
	options         KERNPHYSADDR=0x20000000
	options         KERNVIRTADDR=0xc0000000
	options         AT91C_MASTER_CLOCK=200000000

The board's (64MB of) SDRAM is located at 0x20000000. After tftp-ing the 
kernel.bin image to 0x20000000 with u-boot and starting it the board seems to 
hang. By printing bytes to the DBGU serial port I've been able to trace the 
execution through "arm/locore.S" up to the point where the MMU is enabled 
with the following code:

	/* Enable MMU */
	mrc     p15, 0, r0, c1, c0, 0
	orr     r0, r0, #CPU_CONTROL_MMU_ENABLE
	mcr     p15, 0, r0, c1, c0, 0
	nop
	nop
	nop
	CPWAIT(r0)

Either the CPU halts somewhere in this piece of code, or my DBGU printing 
macro doesn't work after enabling the MMU and the code halts somewhere 
else. ;-)

Any ideas as to what could be going wrong here or tips to debug this further?


[1] : http://www.taskit.de/produkte/stamp/starterkit.htm


Thanks,
-- 
Daan Vreeken
Vitsch Electronics
http://Vitsch.nl
tel: +31-(0)40-7113050 / +31-(0)6-46210825
KvK nr: 17174380