target/xtensa: add clock input to xtensa CPU

Create clock input for the xtensa CPU device and initialize its
frequency to the default core frequency specified in the config.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

target/xtensa/cpu.c

@@ -34,6 +34,7 @@
 #include "fpu/softfloat.h"
 #include "qemu/module.h"
 #include "migration/vmstate.h"
+#include "hw/qdev-clock.h"
 
 
 static void xtensa_cpu_set_pc(CPUState *cs, vaddr value)
@@ -172,9 +173,23 @@ static void xtensa_cpu_initfn(Object *obj)
     memory_region_init_io(env->system_er, obj, NULL, env, "er",
                           UINT64_C(0x100000000));
     address_space_init(env->address_space_er, env->system_er, "ER");
+
+    cpu->clock = qdev_init_clock_in(DEVICE(obj), "clk-in", NULL, cpu, 0);
+    clock_set_hz(cpu->clock, env->config->clock_freq_khz * 1000);
 #endif
 }
 
+XtensaCPU *xtensa_cpu_create_with_clock(const char *cpu_type, Clock *cpu_refclk)
+{
+    DeviceState *cpu;
+
+    cpu = DEVICE(object_new(cpu_type));
+    qdev_connect_clock_in(cpu, "clk-in", cpu_refclk);
+    qdev_realize(cpu, NULL, &error_abort);
+
+    return XTENSA_CPU(cpu);
+}
+
 #ifndef CONFIG_USER_ONLY
 static const VMStateDescription vmstate_xtensa_cpu = {
     .name = "cpu",

target/xtensa/cpu.h

@@ -31,6 +31,7 @@
 #include "cpu-qom.h"
 #include "qemu/cpu-float.h"
 #include "exec/cpu-defs.h"
+#include "hw/clock.h"
 #include "xtensa-isa.h"
 
 /* Xtensa processors have a weak memory model */
@@ -559,6 +560,7 @@ struct ArchCPU {
     CPUState parent_obj;
     /*< public >*/
 
+    Clock *clock;
     CPUNegativeOffsetState neg;
     CPUXtensaState env;
 };
@@ -793,4 +795,7 @@ static inline void cpu_get_tb_cpu_state(CPUXtensaState *env, target_ulong *pc,
     }
 }
 
+XtensaCPU *xtensa_cpu_create_with_clock(const char *cpu_type,
+                                        Clock *cpu_refclk);
+
 #endif

target/xtensa/op_helper.c

@@ -38,12 +38,12 @@
 
 void HELPER(update_ccount)(CPUXtensaState *env)
 {
+    XtensaCPU *cpu = XTENSA_CPU(env_cpu(env));
     uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 
     env->ccount_time = now;
     env->sregs[CCOUNT] = env->ccount_base +
-        (uint32_t)((now - env->time_base) *
-                   env->config->clock_freq_khz / 1000000);
+        (uint32_t)clock_ns_to_ticks(cpu->clock, now - env->time_base);
 }
 
 void HELPER(wsr_ccount)(CPUXtensaState *env, uint32_t v)
@@ -59,6 +59,7 @@ void HELPER(wsr_ccount)(CPUXtensaState *env, uint32_t v)
 
 void HELPER(update_ccompare)(CPUXtensaState *env, uint32_t i)
 {
+    XtensaCPU *cpu = XTENSA_CPU(env_cpu(env));
     uint64_t dcc;
 
     qatomic_and(&env->sregs[INTSET],
@@ -66,7 +67,7 @@ void HELPER(update_ccompare)(CPUXtensaState *env, uint32_t i)
     HELPER(update_ccount)(env);
     dcc = (uint64_t)(env->sregs[CCOMPARE + i] - env->sregs[CCOUNT] - 1) + 1;
     timer_mod(env->ccompare[i].timer,
-              env->ccount_time + (dcc * 1000000) / env->config->clock_freq_khz);
+              env->ccount_time + clock_ticks_to_ns(cpu->clock, dcc));
     env->yield_needed = 1;
 }