diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index d637b396f81c814439f9ab289f0d2c820a90e2e7..6ad4c1161518dd546c2ff0e6b2c6e75bf7c961af 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -393,6 +393,28 @@ config PARSE_BOOTPARAM
 
 	  If unsure, say Y.
 
+choice
+	prompt "Semihosting interface"
+	default XTENSA_SIMCALL_ISS
+	depends on XTENSA_PLATFORM_ISS
+	help
+	  Choose semihosting interface that will be used for serial port,
+	  block device and networking.
+
+config XTENSA_SIMCALL_ISS
+	bool "simcall"
+	help
+	  Use simcall instruction. simcall is only available on simulators,
+	  it does nothing on hardware.
+
+config XTENSA_SIMCALL_GDBIO
+	bool "GDBIO"
+	help
+	  Use break instruction. It is available on real hardware when GDB
+	  is attached to it via JTAG.
+
+endchoice
+
 config BLK_DEV_SIMDISK
 	tristate "Host file-based simulated block device support"
 	default n
diff --git a/arch/xtensa/platforms/iss/include/platform/simcall-gdbio.h b/arch/xtensa/platforms/iss/include/platform/simcall-gdbio.h
new file mode 100644
index 0000000000000000000000000000000000000000..e642860e25a8cf06be4c6f17393a3d7c59ef6e91
--- /dev/null
+++ b/arch/xtensa/platforms/iss/include/platform/simcall-gdbio.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2021 Cadence Design Systems Inc. */
+
+#ifndef _XTENSA_PLATFORM_ISS_SIMCALL_GDBIO_H
+#define _XTENSA_PLATFORM_ISS_SIMCALL_GDBIO_H
+
+/*
+ *  System call like services offered by the GDBIO host.
+ */
+
+#define SYS_open	-2
+#define SYS_close	-3
+#define SYS_read	-4
+#define SYS_write	-5
+#define SYS_lseek	-6
+
+static int errno;
+
+static inline int __simc(int a, int b, int c, int d)
+{
+	register int a1 asm("a2") = a;
+	register int b1 asm("a6") = b;
+	register int c1 asm("a3") = c;
+	register int d1 asm("a4") = d;
+	__asm__ __volatile__ (
+			"break 1, 14\n"
+			: "+r"(a1), "+r"(c1)
+			: "r"(b1), "r"(d1)
+			: "memory");
+	errno = c1;
+	return a1;
+}
+
+#endif /* _XTENSA_PLATFORM_ISS_SIMCALL_GDBIO_H */
diff --git a/arch/xtensa/platforms/iss/include/platform/simcall.h b/arch/xtensa/platforms/iss/include/platform/simcall.h
index 612080bf0b3dcde92509292b1c4ef06e5c4921c5..e1ec50ce39ee33064a5a353c5c90b90e40581604 100644
--- a/arch/xtensa/platforms/iss/include/platform/simcall.h
+++ b/arch/xtensa/platforms/iss/include/platform/simcall.h
@@ -12,11 +12,23 @@
 #ifndef _XTENSA_PLATFORM_ISS_SIMCALL_H
 #define _XTENSA_PLATFORM_ISS_SIMCALL_H
 
+#include <linux/bug.h>
+
+#ifdef CONFIG_XTENSA_SIMCALL_ISS
 #include <platform/simcall-iss.h>
+#endif
+#ifdef CONFIG_XTENSA_SIMCALL_GDBIO
+#include <platform/simcall-gdbio.h>
+#endif
 
 static inline int simc_exit(int exit_code)
 {
+#ifdef SYS_exit
 	return __simc(SYS_exit, exit_code, 0, 0);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+	return -1;
+#endif
 }
 
 static inline int simc_open(const char *file, int flags, int mode)
@@ -31,7 +43,12 @@ static inline int simc_close(int fd)
 
 static inline int simc_ioctl(int fd, int request, void *arg)
 {
+#ifdef SYS_ioctl
 	return __simc(SYS_ioctl, fd, request, (int) arg);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+	return -1;
+#endif
 }
 
 static inline int simc_read(int fd, void *buf, size_t count)
@@ -46,9 +63,14 @@ static inline int simc_write(int fd, const void *buf, size_t count)
 
 static inline int simc_poll(int fd)
 {
+#ifdef SYS_select_one
 	long timeval[2] = { 0, 0 };
 
 	return __simc(SYS_select_one, fd, XTISS_SELECT_ONE_READ, (int)&timeval);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+	return -1;
+#endif
 }
 
 static inline int simc_lseek(int fd, uint32_t off, int whence)
@@ -58,17 +80,31 @@ static inline int simc_lseek(int fd, uint32_t off, int whence)
 
 static inline int simc_argc(void)
 {
+#ifdef SYS_iss_argc
 	return __simc(SYS_iss_argc, 0, 0, 0);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+	return 0;
+#endif
 }
 
 static inline int simc_argv_size(void)
 {
+#ifdef SYS_iss_argv_size
 	return __simc(SYS_iss_argv_size, 0, 0, 0);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+	return 0;
+#endif
 }
 
 static inline void simc_argv(void *buf)
 {
+#ifdef SYS_iss_set_argv
 	__simc(SYS_iss_set_argv, (int)buf, 0, 0);
+#else
+	WARN_ONCE(1, "%s: not implemented\n", __func__);
+#endif
 }
 
 #endif /* _XTENSA_PLATFORM_ISS_SIMCALL_H */