hw/intc/arm_gic: Drop running_irq and last_active arrays

The running_irq and last_active arrays represent state which
doesn't exist in a real hardware GIC. The only thing we use
them for is updating the running priority when an interrupt
is completed, but in fact we can use the active-priority
registers to do this. The running priority is always the
priority corresponding to the lowest set bit in the active
priority registers, because only one interrupt at any
particular priority can be active at once.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1438089748-5528-5-git-send-email-peter.maydell@linaro.org

1 files changed, 0 insertions, 10 deletions

diff --git a/include/hw/intc/arm_gic_common.h b/include/hw/intc/arm_gic_common.h
index c4ec2c3dea..b9dfe05c6e 100644
--- a/include/hw/intc/arm_gic_common.h
+++ b/include/hw/intc/arm_gic_common.h
@@ -68,7 +68,6 @@ typedef struct GICState {
     uint8_t irq_target[GIC_MAXIRQ];
     uint8_t priority1[GIC_INTERNAL][GIC_NCPU];
     uint8_t priority2[GIC_MAXIRQ - GIC_INTERNAL];
-    uint16_t last_active[GIC_MAXIRQ][GIC_NCPU];
     /* For each SGI on the target CPU, we store 8 bits
      * indicating which source CPUs have made this SGI
      * pending on the target CPU. These correspond to
@@ -78,7 +77,6 @@ typedef struct GICState {
     uint8_t sgi_pending[GIC_NR_SGIS][GIC_NCPU];
 
     uint16_t priority_mask[GIC_NCPU];
-    uint16_t running_irq[GIC_NCPU];
     uint16_t running_priority[GIC_NCPU];
     uint16_t current_pending[GIC_NCPU];
 
@@ -96,14 +94,6 @@ typedef struct GICState {
      * If an interrupt for preemption level X is active, then
      *   APRn[X mod 32] == 0b1,  where n = X / 32
      * otherwise the bit is clear.
-     *
-     * TODO: rewrite the interrupt acknowlege/complete routines to use
-     * the APR registers to track the necessary information to update
-     * s->running_priority[] on interrupt completion (ie completely remove
-     * last_active[][] and running_irq[]). This will be necessary if we ever
-     * want to support TCG<->KVM migration, or TCG guests which can
-     * do power management involving powering down and restarting
-     * the GIC.
      */
     uint32_t apr[GIC_NR_APRS][GIC_NCPU];
     uint32_t nsapr[GIC_NR_APRS][GIC_NCPU];