riscv: Add 3 SBI wrapper functions to get cpu manufacturer information

Add 3 wrapper functions to get vendor id, architecture id and implement id
from M-mode
Signed-off-by: NVincent Chen <vincent.chen@sifive.com>
Reviewed-by: NAnup Patel <anup@brainfault.org>
Signed-off-by: NPalmer Dabbelt <palmerdabbelt@google.com>

arch/riscv/include/asm/sbi.h

@@ -97,6 +97,9 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
 
 void sbi_console_putchar(int ch);
 int sbi_console_getchar(void);
+long sbi_get_mvendorid(void);
+long sbi_get_marchid(void);
+long sbi_get_mimpid(void);
 void sbi_set_timer(uint64_t stime_value);
 void sbi_shutdown(void);
 void sbi_clear_ipi(void);

arch/riscv/kernel/sbi.c

@@ -547,6 +547,21 @@ static inline long sbi_get_firmware_version(void)
 	return __sbi_base_ecall(SBI_EXT_BASE_GET_IMP_VERSION);
 }
 
+long sbi_get_mvendorid(void)
+{
+	return __sbi_base_ecall(SBI_EXT_BASE_GET_MVENDORID);
+}
+
+long sbi_get_marchid(void)
+{
+	return __sbi_base_ecall(SBI_EXT_BASE_GET_MARCHID);
+}
+
+long sbi_get_mimpid(void)
+{
+	return __sbi_base_ecall(SBI_EXT_BASE_GET_MIMPID);
+}
+
 static void sbi_send_cpumask_ipi(const struct cpumask *target)
 {
 	struct cpumask hartid_mask;