Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20150706' into staging

target-arm queue:
 * TLBI ALLEI1IS should operate on all CPUs, not just this one
 * Fix interval interrupt of cadence ttc in decrement mode
 * Implement YIELD insn to yield in ARM and Thumb translators
 * ARM GIC: reset all registers
 * arm_mptimer: fix timer shutdown and mode change
 * arm_mptimer: respect IT bit state

# gpg: Signature made Mon Jul  6 10:58:27 2015 BST using RSA key ID 14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"

* remotes/pmaydell/tags/pull-target-arm-20150706:
  arm_mptimer: Respect IT bit state
  arm_mptimer: Fix timer shutdown and mode change
  hw/intc/arm_gic_common.c: Reset all registers
  target-arm: Implement YIELD insn to yield in ARM and Thumb translators
  target-arm: Split DISAS_YIELD from DISAS_WFE
  Fix interval interrupt of cadence ttc when timer is in decrement mode
  target-arm: fix write helper for TLBI ALLE1IS
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/intc/arm_gic_common.c

@@ -123,7 +123,7 @@ static void arm_gic_common_realize(DeviceState *dev, Error **errp)
 static void arm_gic_common_reset(DeviceState *dev)
 {
     GICState *s = ARM_GIC_COMMON(dev);
-    int i;
+    int i, j;
     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
     for (i = 0 ; i < s->num_cpu; i++) {
         if (s->revision == REV_11MPCORE) {
@@ -135,15 +135,30 @@ static void arm_gic_common_reset(DeviceState *dev)
         s->running_irq[i] = 1023;
         s->running_priority[i] = 0x100;
         s->cpu_ctlr[i] = 0;
+        s->bpr[i] = GIC_MIN_BPR;
+        s->abpr[i] = GIC_MIN_ABPR;
+        for (j = 0; j < GIC_INTERNAL; j++) {
+            s->priority1[j][i] = 0;
+        }
+        for (j = 0; j < GIC_NR_SGIS; j++) {
+            s->sgi_pending[j][i] = 0;
+        }
     }
     for (i = 0; i < GIC_NR_SGIS; i++) {
         GIC_SET_ENABLED(i, ALL_CPU_MASK);
         GIC_SET_EDGE_TRIGGER(i);
     }
-    if (s->num_cpu == 1) {
+
+    for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
+        s->priority2[i] = 0;
+    }
+
+    for (i = 0; i < GIC_MAXIRQ; i++) {
         /* For uniprocessor GICs all interrupts always target the sole CPU */
-        for (i = 0; i < GIC_MAXIRQ; i++) {
+        if (s->num_cpu == 1) {
             s->irq_target[i] = 1;
+        } else {
+            s->irq_target[i] = 0;
         }
     }
     s->ctlr = 0;

hw/timer/arm_mptimer.c

@@ -38,7 +38,7 @@ static inline int get_current_cpu(ARMMPTimerState *s)
 
 static inline void timerblock_update_irq(TimerBlock *tb)
 {
-    qemu_set_irq(tb->irq, tb->status);
+    qemu_set_irq(tb->irq, tb->status && (tb->control & 4));
 }
 
 /* Return conversion factor from mpcore timer ticks to qemu timer ticks.  */
@@ -122,11 +122,18 @@ static void timerblock_write(void *opaque, hwaddr addr,
     case 8: /* Control.  */
         old = tb->control;
         tb->control = value;
-        if (((old & 1) == 0) && (value & 1)) {
-            if (tb->count == 0 && (tb->control & 2)) {
+        if (value & 1) {
+            if ((old & 1) && (tb->count != 0)) {
+                /* Do nothing if timer is ticking right now.  */
+                break;
+            }
+            if (tb->control & 2) {
                 tb->count = tb->load;
             }
             timerblock_reload(tb, 1);
+        } else if (old & 1) {
+            /* Shutdown the timer.  */
+            timer_del(tb->timer);
         }
         break;
     case 12: /* Interrupt status.  */

hw/timer/cadence_ttc.c

@@ -208,15 +208,14 @@ static void cadence_timer_sync(CadenceTimerState *s)
             s->reg_intr |= (2 << i);
         }
     }
+    if ((x < 0) || (x >= interval)) {
+        s->reg_intr |= (s->reg_count & COUNTER_CTRL_INT) ?
+            COUNTER_INTR_IV : COUNTER_INTR_OV;
+    }
     while (x < 0) {
         x += interval;
     }
     s->reg_value = (uint32_t)(x % interval);
-
-    if (s->reg_value != x) {
-        s->reg_intr |= (s->reg_count & COUNTER_CTRL_INT) ?
-            COUNTER_INTR_IV : COUNTER_INTR_OV;
-    }
     cadence_timer_update(s);
 }
 

target-arm/helper.c

@@ -2441,7 +2441,7 @@ static const ARMCPRegInfo v8_cp_reginfo[] = {
     { .name = "TLBI_ALLE1IS", .state = ARM_CP_STATE_AA64,
       .opc0 = 1, .opc1 = 4, .crn = 8, .crm = 3, .opc2 = 4,
       .access = PL2_W, .type = ARM_CP_NO_RAW,
-      .writefn = tlbiall_write },
+      .writefn = tlbiall_is_write },
     { .name = "TLBI_VMALLE1IS", .state = ARM_CP_STATE_AA64,
       .opc0 = 1, .opc1 = 0, .crn = 8, .crm = 3, .opc2 = 0,
       .access = PL1_W, .type = ARM_CP_NO_RAW,

target-arm/helper.h

@@ -50,6 +50,7 @@ DEF_HELPER_2(exception_internal, void, env, i32)
 DEF_HELPER_4(exception_with_syndrome, void, env, i32, i32, i32)
 DEF_HELPER_1(wfi, void, env)
 DEF_HELPER_1(wfe, void, env)
+DEF_HELPER_1(yield, void, env)
 DEF_HELPER_1(pre_hvc, void, env)
 DEF_HELPER_2(pre_smc, void, env, i32)
 

target-arm/op_helper.c

@@ -323,13 +323,25 @@ void HELPER(wfi)(CPUARMState *env)
 
 void HELPER(wfe)(CPUARMState *env)
 {
-    CPUState *cs = CPU(arm_env_get_cpu(env));
-
-    /* Don't actually halt the CPU, just yield back to top
+    /* This is a hint instruction that is semantically different
+     * from YIELD even though we currently implement it identically.
+     * Don't actually halt the CPU, just yield back to top
      * level loop. This is not going into a "low power state"
      * (ie halting until some event occurs), so we never take
      * a configurable trap to a different exception level.
      */
+    HELPER(yield)(env);
+}
+
+void HELPER(yield)(CPUARMState *env)
+{
+    ARMCPU *cpu = arm_env_get_cpu(env);
+    CPUState *cs = CPU(cpu);
+
+    /* This is a non-trappable hint instruction that generally indicates
+     * that the guest is currently busy-looping. Yield control back to the
+     * top level loop so that a more deserving VCPU has a chance to run.
+     */
     cs->exception_index = EXCP_YIELD;
     cpu_loop_exit(cs);
 }

target-arm/translate-a64.c

@@ -1199,6 +1199,8 @@ static void handle_hint(DisasContext *s, uint32_t insn,
         s->is_jmp = DISAS_WFI;
         return;
     case 1: /* YIELD */
+        s->is_jmp = DISAS_YIELD;
+        return;
     case 2: /* WFE */
         s->is_jmp = DISAS_WFE;
         return;
@@ -11107,6 +11109,10 @@ void gen_intermediate_code_internal_a64(ARMCPU *cpu,
             gen_a64_set_pc_im(dc->pc);
             gen_helper_wfe(cpu_env);
             break;
+        case DISAS_YIELD:
+            gen_a64_set_pc_im(dc->pc);
+            gen_helper_yield(cpu_env);
+            break;
         case DISAS_WFI:
             /* This is a special case because we don't want to just halt the CPU
              * if trying to debug across a WFI.

target-arm/translate.c

@@ -4080,6 +4080,10 @@ static void gen_rfe(DisasContext *s, TCGv_i32 pc, TCGv_i32 cpsr)
 static void gen_nop_hint(DisasContext *s, int val)
 {
     switch (val) {
+    case 1: /* yield */
+        gen_set_pc_im(s, s->pc);
+        s->is_jmp = DISAS_YIELD;
+        break;
     case 3: /* wfi */
         gen_set_pc_im(s, s->pc);
         s->is_jmp = DISAS_WFI;
@@ -11459,6 +11463,9 @@ static inline void gen_intermediate_code_internal(ARMCPU *cpu,
         case DISAS_WFE:
             gen_helper_wfe(cpu_env);
             break;
+        case DISAS_YIELD:
+            gen_helper_yield(cpu_env);
+            break;
         case DISAS_SWI:
             gen_exception(EXCP_SWI, syn_aa32_svc(dc->svc_imm, dc->thumb),
                           default_exception_el(dc));

target-arm/translate.h

@@ -103,6 +103,7 @@ static inline int default_exception_el(DisasContext *s)
 #define DISAS_WFE 7
 #define DISAS_HVC 8
 #define DISAS_SMC 9
+#define DISAS_YIELD 10
 
 #ifdef TARGET_AARCH64
 void a64_translate_init(void);