I am having some difficulty booting a FILO (r95) payload using coreboot-v2 (r4291). My target is a via vb7001g, but I'm using the epia-cn target since the boards are practically identical afaict. The only hardware change I've made is using a 2MB flash chip. I was able to boot some simple payloads using coreboot-v2 r4121, too.
So anyway, after doing some tracing using printk's, it seems the problem occurs in build_lb_mem() in arch/i386/boot/coreboot_tables.c when it attempts to record where memory ranges live.
Added print output in build_lb_mem(): printk_debug("%s: entered\n", __func__); /* Record where the lb memory ranges will live */ mem = lb_memory(head); printk_debug("%s: mem: 0x%p, mem->size = 0x%x\n", __func__, mem, mem->size); printk_debug("\tmem->size: 0x%x\n", mem->size); mem_ranges = mem; printk_debug("\tmem_ranges->size: 0x%x\n", mem_ranges->size);
lb_memory() is short, so I'll print the full thing (I only added the two printk's, the rest is unmodified): struct lb_memory *lb_memory(struct lb_header *header) { struct lb_record *rec; struct lb_memory *mem; printk_debug("%s: entered, header: 0x%p", __func__, header); rec = lb_new_record(header); mem = (struct lb_memory *)rec; mem->tag = LB_TAG_MEMORY; mem->size = sizeof(*mem); printk_debug("%s: exiting, mem: 0x%p, mem->size = 0x%x\n", __func__, mem, mem->size); return mem; }
...and finally, a snippet from serial output: build_lb_mem: entered, head: 0x3fff0800 lb_memory: entered, header: 0x3fff0800 lb_memory: exiting, mem: 0x3fff0817, mem->size = 0x8 build_lb_mem: mem: 0x3fff0817, mem->size = 0xffffffff mem->size: 0xffffffff mem_ranges->size: 0xffffffff
So that's pretty weird. But what's also weird is that if I set mem->size manually after it returns from lb_memory() and then set mem_ranges, it somehow gets set back to 0xffffffff. Here's build_lb_mem() with even more printk's added to show that: printk_debug("%s: entered, head: 0x%p\n", __func__); /* Record where the lb memory ranges will live */ mem = lb_memory(head); printk_debug("%s: mem: 0x%p, mem->size = 0x%x\n", __func__, mem, mem->size); mem->size = 8; /* FIXME: stupid idea */ printk_debug("\tmem->size (after being manually set): 0x%x\n", mem->size); mem_ranges = mem; printk_debug("\tmem->size after setting mem_ranges: 0x%x\n", mem->size); printk_debug("\tmem_ranges->size: 0x%x\n", mem_ranges->size);
...and the serial console output: build_lb_mem: entered, head: 0x3fff0800 lb_memory: entered, header: 0x3fff0800 lb_memory: exiting, mem: 0x3fff0817, mem->size = 0x8 build_lb_mem: mem: 0x3fff0817, mem->size = 0xffffffff mem->size (after being manually set): 0x8 mem->size after setting mem_ranges: 0xffffffff mem_ranges->size: 0xffffffff
Any ideas on what could be happening or where to go next for debugging?