Paul Mackerras 12a3d76217 Implement hrfid and make MSR[HV] always 1 ...

Implementations without hypervisor/LPAR support are permitted by the
architecture, but should have MSR[HV] forced to be 1 at all times, not
0, and should implement various instructions and registers that are
only accessible in hypervisor mode.

This commit implements MSR[HV] as a constant 1 bit and adds the hrfid
instruction, which behaves exactly the same as rfid except that it
reads HSRR0/1 instead of SRR0/1.  We already have HSRR0/1 and HSPRG0/1
implemented.

When HV=1, Linux expects external interrupts to arrive as hypervisor
interrupts, so this adds support for hypervisor interrupts (i.e.,
those that set HSRR0/1) and makes the external interrupt be a
hypervisor interrupt.  (If we had an LPCR register, the LPES bit would
control this, but we don't.)  The xics test is updated to read HSRR0/1
after an external interrupt.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

2024-12-20 17:40:04 +11:00

24 KiB

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