Hi Joe,
On Wed, 6 Nov 2013 09:18:53 -0700, Joe Kulikauskas jkulikauskas@cardinalpeak.com wrote:
Hi,
Rob, yes that's correct.
To Albert's question: the disassembled instruction I had showed LDR R3,ff0a0fc0 is load of r3 with address of the variable holding the stack address; "this write" is the str which I've now copied in below. IRQ_STACK_START_IN = gd->irq_sp + 8; ff0a0fb0: e5992044 ldr r2, [r9, #68] ; 0x44 ff0a0fb4: e2822008 add r2, r2, #8 ff0a0fb8: e5832000 str r2, [r3]
For my target, IIRC the write to flash caused problem in the flash controller hardware, breaking further instruction fetches. On other platforms the write to flash may fail silently. But the issue is that interrupt_init() moving into board_init_f (i.e. before relocation) generally just doesn't work right.
Joe
Thanks Rob and Joe for the clarification.
Indeed interrupt_init() cannot execute before relocation as it sets globals.
Further, interrupt_init() uses globals to communicate with start.S. This should be changed. I understand that is because the interrupt handlers actually set the interrupt stack when they are invoked -- and that is unnecessary; stacks should be set up as soon as their addresses are known.
I'll revert the patch as soon as I finish getting the current PRs in.
I have a start.S rewrite effort underway whcuh I should post soon. I'll add to it a change to the way stacks are initialized.
Amicalement,