On 25/09/2023 6:37 pm, Shawn Anastasio wrote: > On 9/22/23 3:03 PM, Andrew Cooper wrote: >> Several things. >> >> First, Shawn: PPC has gained a HAS_PDX, the deletion of which needs >> merging into this patch. >> >> It was added as part of 4a2f68f909304 which was "minimal to build". >> This series address the issue you presumably encountered where pdx.c >> appears to be optional but wasn't. >> > That's correct, build was broken without HAS_PDX. > >> Do PPC platforms have (or potentially have) sparse RAM banks? >> > Yes, they do. Especially on POWER9, it is very common for there to be > large gaps in the physical address space between RAM banks. > >> If like x86 the answer is definitely no, then you want to have >> PDX_COMPRESSION=n >> >> If the answer is definitely yes always, then you want PDX_COMPRESSION=y >> >> If the answer is system specific, then you want to offer users a choice. > It looks like PDX_COMPRESSION=y would probably make the most sense for > ppc, but I'm not against making it a choice.
Thanks. I'll make suitable adjustments. ~Andrew
