riscv vmm: SBI timer support
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Authored by br on Wed, Dec 18, 4:06 PM.

Details

Reviewers

mhorne
jrtc27
markj

Group Reviewers

bhyve

Summary

Add SBI timer implementation and rework interrupts handling.

This is needed for EIC7700 which does not have SSTC extension supported.

Add new "interrupts_pending" field. Use it for timer interrupt only for now, but later we can extend to store all pending interrupts (IPI and External).

Test Plan

With this I'm able to boot SMP guest on HiFive Premier P550.

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Event Timeline

br created this revision.Wed, Dec 18, 4:06 PM

Herald added a reviewer: bhyve. · View Herald TranscriptWed, Dec 18, 4:06 PM

Herald added subscribers: riscv, bcran, rgrimes. · View Herald Transcript

br requested review of this revision.Wed, Dec 18, 4:06 PM

Wait so you put up a patch to disable Sstc before an alternative was provided?

In D48133#1097519, @jrtc27 wrote:

Wait so you put up a patch to disable Sstc before an alternative was provided?

:-)
Well it was still working in QEMU and Spike that both have SSTC.
On EIC7700 I needed to disable SSTC advertisement before I can work on SBI timer...otherwise the guest runs an invalid instruction.