Details

Reviewers

nwhitehorn
breno.leitao_gmail.com

Commits

rS333912: Add support for the XIVE XICS emulation mode for POWER9 systems

Summary

POWER9 systems use a new interrupt controller, XIVE, managed through OPAL
firmware calls. The OPAL firmware includes support for emulating the previous
generation XICS presentation layer in addition to a new "XIVE Exploitation"
mode. As a stopgap until we have XIVE exploitation mode, enable XICS emulation
mode so that we at least have an interrupt controller.

Since the CPPR is local to the current CPU, it cannot be updated for APs when
initializing on the BSP. This adds a new function, directly called by the
powernv platform code, to initialize the CPPR on AP bringup.

Diff Detail

Repository

rS FreeBSD src repository - subversion

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Build Status

Buildable 16712
Build 16606: arc lint + arc unit

Event Timeline

jhibbits created this revision.May 19 2018, 7:58 PM

Herald added a subscriber: imp. · View Herald TranscriptMay 19 2018, 7:58 PM

Harbormaster completed remote builds in B16703: Diff 42743.May 19 2018, 7:58 PM

nwhitehorn added inline comments.May 19 2018, 8:40 PM

sys/powerpc/aim/mp_cpudep.c
99	HVICE is a reserved bit on POWER8 (ISA 2.07) and should be set only on POWER9 (Power ISA 3+). This should probably be some switch on the ISA version from CPU features rather than the PVR, anyway.
406	Ditto here with respect to POWER8.
sys/powerpc/include/spr.h
238	Note that this is only in ISA >= 3?
sys/powerpc/powernv/platform_powernv.c
156–159	See: POWER ISA 3 comments.
465	This method is called only on APs, so no need for this if.
466	Why not do this inline? I assume this whole mode will be removed once XIVE support lands.
sys/powerpc/pseries/xics.c
561	This is guaranteed to the be the root PIC. Why not rely on that?

jhibbits added inline comments.May 20 2018, 12:52 AM

sys/powerpc/aim/mp_cpudep.c
99	Easy enough to address. I'll set up a 'lpcr' variable at platform init time appropriate for the CPU (can use cpu_featuers at this point, since it's initialized much earlier than platform)
sys/powerpc/include/spr.h
238	Can do, will do
sys/powerpc/pseries/xics.c
561	True, I could do that. I went this route as a sort of seatbelt, but it's probably overkill.

Address Nathan's comments

Use root_pic instead of locally stored PIC reference.
Create a lpcr variable to hold the LPCR config, which is different from 2.0x and 3.0.

Harbormaster completed remote builds in B16709: Diff 42751.May 20 2018, 2:00 AM

See the comment on line 467 about powernv_smp_ap_init(). Otherwise, looks good.

sys/powerpc/powernv/platform_powernv.c
157	Shouldn't this be earlier/elsewhere? It's not exactly PowerNV specific (insofar as PowerNV means "opal + FDT"). This is not a blocking comment, though.