A colleague of mine reported on a hang during boot on a SuperMicro board
(with ACPI off):
http://lists.freebsd.org/pipermail/freebsd-current/2004-March/023045.html
with some more analysis:
http://lists.freebsd.org/pipermail/freebsd-current/2004-July/030827.html
as it turns out it doesn't actually always hang, it usually takes 30-45
minutes to boot. The problem comes from the PNP0c01 entry in the PNP
BIOS, and specifically the entry:
PNP0c01: adding fixed memory32 range 0xfff80000-0xffffffff, size=0x80000
In isa/isa_common.c:isa_find_memory() there's a for loop that looks for
space for the memory block:
for (start = config->ic_mem[i].ir_start,
end = config->ic_mem[i].ir_end,
align = config->ic_mem[i].ir_align;
start + size - 1 <= end;
start += align) {
For some reason the attempt to use the given memory region fails. After
adding align to start, start + size - 1 wraps and the <= end test remains
true.
The following patch gets this board booting for me:
--- isa_common.c@@/main/sandvine_bsd_5_main/0 2005-01-02 15:39:24.000000000
-0500
+++ isa_common.c 2005-01-02 23:59:06.000000000 -0500
@@ -149,7 +149,7 @@
for (start = config->ic_mem[i].ir_start,
end = config->ic_mem[i].ir_end,
align = config->ic_mem[i].ir_align;
- start + size - 1 <= end;
+ start + size - 1 <= end && start + size >
start;
start += align) {
bus_set_resource(child, SYS_RES_MEMORY, i,
start, size);