[PATCH 5/5] target/arm/helper: Implement CNTHCTL_EL2.CNT[VP]MASK

[Jean-Philippe Brucker]

When FEAT_RME is implemented, these bits override the value of
CNT[VP]_CTL_EL0.IMASK in Realm and Root state.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
 target/arm/helper.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 2017b11795..5b173a827f 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -2608,6 +2608,23 @@ static uint64_t gt_get_countervalue(CPUARMState *env)
     return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) / gt_cntfrq_period_ns(cpu);
 }
 
+static bool gt_is_masked(CPUARMState *env, int timeridx)
+{
+    ARMSecuritySpace ss = arm_security_space(env);
+
+    /*
+     * If bits CNTHCTL_EL2.CNT[VP]MASK are set, they override
+     * CNT[VP]_CTL_EL0.IMASK. They are RES0 in Secure and NonSecure state.
+     */
+    if ((ss == ARMSS_Root || ss == ARMSS_Realm) &&
+        ((timeridx == GTIMER_VIRT && extract64(env->cp15.cnthctl_el2, 18, 1)) 
||
+         (timeridx == GTIMER_PHYS && extract64(env->cp15.cnthctl_el2, 19, 
1)))) {
+        return true;
+    }
+
+    return env->cp15.c14_timer[timeridx].ctl & 2;
+}
+
 static void gt_recalc_timer(ARMCPU *cpu, int timeridx)
 {
     ARMGenericTimer *gt = &cpu->env.cp15.c14_timer[timeridx];
@@ -2627,7 +2644,7 @@ static void gt_recalc_timer(ARMCPU *cpu, int timeridx)
 
         gt->ctl = deposit32(gt->ctl, 2, 1, istatus);
 
-        irqstate = (istatus && !(gt->ctl & 2));
+        irqstate = (istatus && !gt_is_masked(&cpu->env, timeridx));
         qemu_set_irq(cpu->gt_timer_outputs[timeridx], irqstate);
 
         if (istatus) {
@@ -2759,7 +2776,7 @@ static void gt_ctl_write(CPUARMState *env, const 
ARMCPRegInfo *ri,
          * IMASK toggled: don't need to recalculate,
          * just set the interrupt line based on ISTATUS
          */
-        int irqstate = (oldval & 4) && !(value & 2);
+        int irqstate = (oldval & 4) && !gt_is_masked(env, timeridx);
 
         trace_arm_gt_imask_toggle(timeridx, irqstate);
         qemu_set_irq(cpu->gt_timer_outputs[timeridx], irqstate);
-- 
2.41.0