target/riscv: cpu: Implement get_arch_id callback

Implement the callback for getting the architecture-dependent CPU ID ie
mhartid.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20230303065055.915652-2-mchitale@ventanamicro.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

target/riscv/cpu.c

@@ -1301,6 +1301,13 @@ static const char *riscv_gdb_get_dynamic_xml(CPUState *cs, const char *xmlname)
 }
 
 #ifndef CONFIG_USER_ONLY
+static int64_t riscv_get_arch_id(CPUState *cs)
+{
+    RISCVCPU *cpu = RISCV_CPU(cs);
+
+    return cpu->env.mhartid;
+}
+
 #include "hw/core/sysemu-cpu-ops.h"
 
 static const struct SysemuCPUOps riscv_sysemu_ops = {
@@ -1355,6 +1362,7 @@ static void riscv_cpu_class_init(ObjectClass *c, void *data)
     cc->disas_set_info = riscv_cpu_disas_set_info;
 #ifndef CONFIG_USER_ONLY
     cc->sysemu_ops = &riscv_sysemu_ops;
+    cc->get_arch_id = riscv_get_arch_id;
 #endif
     cc->gdb_arch_name = riscv_gdb_arch_name;
     cc->gdb_get_dynamic_xml = riscv_gdb_get_dynamic_xml;