hv: implement cpu dead and cpu idle for riscv

implement arch_cpu_dead and arch_cpu_do_idle for riscv, arch_cpu_dead and
arch_cpu_do_idle will be called by common module.

Tracked-On: #8812
Signed-off-by: Haicheng Li <haicheng.li@outlook.com>
Signed-off-by: Xue Bosheng <bosheng.xue@intel.com>
Acked-by: Wang, Yu1 <yu1.wang@intel.com>

hypervisor/arch/riscv/cpu.c

@@ -15,6 +15,7 @@
 #include <delay.h>
 #include <asm/sbi.h>
 #include <asm/pgtable.h>
+#include <schedule.h>
 
 /*
  * This array contains the hart IDs for each physial cpu.
@@ -114,3 +115,16 @@ void arch_start_pcpu(uint16_t pcpu_id)
 		pr_fatal("Failed to start cpu%hu by SBI HSM", pcpu_id);
 	}
 }
+
+void arch_cpu_do_idle(void)
+{
+        asm volatile ("wfi"::);
+}
+
+/**
+ * FIXME: This is a temp solution for now. The formal solution should clear up and put pcpu into a low power state.
+ */
+void arch_cpu_dead(void)
+{
+	while (true) {};
+}

hypervisor/include/arch/riscv/asm/cpu.h

@@ -108,14 +108,6 @@ struct stack_frame {
 /* Define CPU stack alignment */
 #define CPU_STACK_ALIGN	16UL
 
-/**
- * FIXME: This is a temp solution for now. The formal solution should clear up and put pcpu into a low power state.
- */
-static inline void cpu_dead(void)
-{
-	while (true) {};
-}
-
 /* In ACRN, struct per_cpu_region is a critical data structure
  * containing key per-CPU data frequently accessed via get_cpu_var().
  * We use the tp register to store the current logical pCPU ID to