[LinuxBIOS] [PATCH v3] v2, v3: Bug? in CAR setup with CacheSize!={4k, 8k, 16k}

Marc Jones marc.jones at amd.com
Wed Nov 28 23:52:17 CET 2007

Carl-Daniel Hailfinger wrote:
> Marc?
> This has been sitting in my tree for a while now.
> On 16.11.2007 16:00, Carl-Daniel Hailfinger wrote:
>> Hi,
>> v2 and v3 have almost identical CAR setup code with identical bugs for
>> CAR sizes != {4k,8k,16k}. In v3, the erroneous code paths are not
>> triggered and the bug is latent, but we have at a few boards in v2 which
>> trigger these bugs, resulting in holes and/or smaller size of the CAR area.

Sorry, I have been very busy and I have been putting this off.

I think you are correct that CAR expects power of 2 cache sizes. How 
about just error if the size isn't power of 2 between 4K and 64K? If you 
wanted to support non power of 2 you should round up otherwise you might 
write off the end.

Note that Geode platforms don't use the same car file as K8 and has a 
max cache size of 32K. See arch\x86\geodelx\stage0.S


Marc Jones
Senior Firmware Engineer
(970) 226-9684 Office
mailto:Marc.Jones at amd.com

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