[coreboot] fam10/h8dmr: extreme slowness in CBFS memset / memcpy
mylesgw at gmail.com
Tue Jul 21 14:25:38 CEST 2009
> Following up on this - Patrick helped in IRC this evening, and we came to
> conclusion that it's probably *not* an MTRR issue, since we figured out
> code seems to set MTRRs properly.
I wonder what else could cause it to be so slow? It's especially surprising
for the memset, which is pretty simple. Does it use movnti for that?
> We found out after adding an extra MTRR over the flash chip, which did not
> change anything.
Did you disable and re-enable the cache so that the settings take effect?
I guess I would:
1. Add some little benchmark loops reading/writing different areas
a. read ROM & time it
b. read from RAM (cached area) and time it
c. read from RAM (non-cached area)
d. write to RAM (cached area)
2. disable MTRRs to see if it would go even slower.
Sorry that's not much help, but I don't have a fam10 box to try things on.
More information about the coreboot