On 25.03.2009 19:16, Rudolf Marek wrote:
Hello,
During the suspend/resume programming I came to an issue that first 4KB of memory must be clear with 0s because otherwise the resources of K8 will be totally messed up.
It took long to figure it out and here it is:
res = probe_resource(dev, 0x100 + (reg | link));
This is called with dev = NULL and this is no good for probe_resource at all. The attached patch fixes the potential problems and of course the problem itself. On one particular place was missing test if the device really exists. This was copied to fam10 and perhaps the same issue is in v3 (DID NOT check). The rest of the patch is just very paranoid and do all checkings.
This was tested in SimNOW but I believe it will work on real hw too.
Signed-off-by: Rudolf Marek r.marek@assembler.cz
Anyone knows if SimNOW can do breaks on memory ranges?
Because it was quite stupid to get to the bug. When the resources just worked again I used data breakpoint to see what routine it is. Problem was that I needed to find the address where it stop to work.
Maybe we really should allow writes to mem only in _RAMBASE - MEMTOPK range (of course with some exception for table stuff).
--- src/cpu/amd/car/clear_init_ram.c<-->(revision 4026) +++ src/cpu/amd/car/clear_init_ram.c<-->(working copy) @@ -6,7 +6,23 @@ <----->// gcc 3.4.5 will inline the copy_and_run and clear_init_ram in post_cache_as_ram <----->// will reuse %edi as 0 from clear_memory for copy_and_run part, actually it is increased already <----->// so noline clear_init_ram
clear_memory(0, ((CONFIG_LB_MEM_TOPK<<10) - DCACHE_RAM_SIZE));
clear_memory(_RAMBASE, ((CONFIG_LB_MEM_TOPK<<10) -_RAMBASE -DCACHE_RAM_SIZE)); [...]
clear_memory(0, 924);.
Oh btw the suspend/resume works, but the code needs to be fixed on some places. There is a copy_secondary_start_to_1m_below which just uses first 64KB of mem for some reason - I dont understand why it cannot be realocable to something different addr. Please check and tell.
Awesome! Can you add a check to pci_{read,write}_config{8,16,32} for dev!= NULL with a big LOUD warning printk? That would be great and maybe find more bugs.
Regards, Carl-Daniel