target/mips/cpu: Introduce mips_cpu_create_with_clock() helper

Introduce an helper to create a MIPS CPU and connect it to
a reference clock. This helper is not MIPS specific, but so
far only MIPS CPUs need it.

Suggested-by: Huacai Chen <zltjiangshi@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201012095804.3335117-13-f4bug@amsat.org>

target/mips/cpu.c

@@ -288,3 +288,15 @@ static void mips_cpu_register_types(void)
 }
 
 type_init(mips_cpu_register_types)
+
+/* Could be used by generic CPU object */
+MIPSCPU *mips_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 MIPS_CPU(cpu);
+}

target/mips/cpu.h

@@ -1307,4 +1307,16 @@ static inline void cpu_get_tb_cpu_state(CPUMIPSState *env, target_ulong *pc,
                             MIPS_HFLAG_HWRENA_ULR);
 }
 
+/**
+ * mips_cpu_create_with_clock:
+ * @typename: a MIPS CPU type.
+ * @cpu_refclk: this cpu input clock (an output clock of another device)
+ *
+ * Instantiates a MIPS CPU, set the input clock of the CPU to @cpu_refclk,
+ * then realizes the CPU.
+ *
+ * Returns: A #CPUState or %NULL if an error occurred.
+ */
+MIPSCPU *mips_cpu_create_with_clock(const char *cpu_type, Clock *cpu_refclk);
+
 #endif /* MIPS_CPU_H */