amd64_edac: Fix K8 revD and later chip select sizes

Fix DRAM chip select sizes calculation for K8, revisions D and E.

Reported-by: Niklas Söderlund <niklas.soderlund@ericsson.com
Link: http://lkml.kernel.org/r/1320849178-23340-1-git-send-email-niklas.soderlund@ericsson.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
This commit is contained in:
Borislav Petkov 2011-11-09 21:28:43 +01:00 committed by Borislav Petkov
parent f92cae4526
commit 11b0a31473

View File

@ -1132,12 +1132,36 @@ static int k8_dbam_to_chip_select(struct amd64_pvt *pvt, u8 dct,
return ddr2_cs_size(cs_mode, dclr & WIDTH_128);
}
else if (pvt->ext_model >= K8_REV_D) {
unsigned diff;
WARN_ON(cs_mode > 10);
if (cs_mode == 3 || cs_mode == 8)
return 32 << (cs_mode - 1);
else
return 32 << cs_mode;
/*
* the below calculation, besides trying to win an obfuscated C
* contest, maps cs_mode values to DIMM chip select sizes. The
* mappings are:
*
* cs_mode CS size (mb)
* ======= ============
* 0 32
* 1 64
* 2 128
* 3 128
* 4 256
* 5 512
* 6 256
* 7 512
* 8 1024
* 9 1024
* 10 2048
*
* Basically, it calculates a value with which to shift the
* smallest CS size of 32MB.
*
* ddr[23]_cs_size have a similar purpose.
*/
diff = cs_mode/3 + (unsigned)(cs_mode > 5);
return 32 << (cs_mode - diff);
}
else {
WARN_ON(cs_mode > 6);