hw/intc/arm_gicv3_cpuif: Support vLPIs

The CPU interface changes to support vLPIs are fairly minor:
in the parts of the code that currently look at the list registers
to determine the highest priority pending virtual interrupt, we
must also look at the highest priority pending vLPI. To do this
we change hppvi_index() to check the vLPI and return a special-case
value if that is the right virtual interrupt to take. The callsites
(which handle HPPIR and IAR registers and the "raise vIRQ and vFIQ
lines" code) then have to handle this special-case value.

This commit includes two interfaces with the as-yet-unwritten
redistributor code:
 * the new GICv3CPUState::hppvlpi will be set by the redistributor
   (in the same way as the existing hpplpi does for physical LPIs)
 * when the CPU interface acknowledges a vLPI it needs to set it
   to non-pending; the new gicv3_redist_vlpi_pending() function
   (which matches the existing gicv3_redist_lpi_pending() used
   for physical LPIs) is a stub that will be filled in later

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220408141550.1271295-26-peter.maydell@linaro.org

1 files changed, 13 insertions, 0 deletions

diff --git a/hw/intc/gicv3_internal.h b/hw/intc/gicv3_internal.h
index 052aa96c77..2a9d3cf974 100644
--- a/hw/intc/gicv3_internal.h
+++ b/hw/intc/gicv3_internal.h
@@ -612,6 +612,19 @@ void gicv3_redist_process_lpi(GICv3CPUState *cs, int irq, int level);
  */
 void gicv3_redist_process_vlpi(GICv3CPUState *cs, int irq, uint64_t vptaddr,
                                int doorbell, int level);
+/**
+ * gicv3_redist_vlpi_pending:
+ * @cs: GICv3CPUState
+ * @irq: (virtual) interrupt number
+ * @level: level to set @irq to
+ *
+ * Set/clear the pending status of a virtual LPI in the vLPI table
+ * that this redistributor is currently using. (The difference between
+ * this and gicv3_redist_process_vlpi() is that this is called from
+ * the cpuif and does not need to do the not-running-on-this-vcpu checks.)
+ */
+void gicv3_redist_vlpi_pending(GICv3CPUState *cs, int irq, int level);
+
 void gicv3_redist_lpi_pending(GICv3CPUState *cs, int irq, int level);
 /**
  * gicv3_redist_update_lpi: