diff --git a/.github/scripts/core_checker.py b/.github/scripts/core_checker.py
index 97e9bd5901..d9d2799790 100755
--- a/.github/scripts/core_checker.py
+++ b/.github/scripts/core_checker.py
@@ -265,7 +265,8 @@ FREERTOS_IGNORED_FILES = [
     'requirements.txt',
     'run-cbmc-proofs.py',
     '.editorconfig',
-    'lcovrc'
+    'lcovrc',
+    'htif.c', 'htif.h'
 ]
 
 FREERTOS_HEADER = [
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/FreeRTOSConfig.h b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/FreeRTOSConfig.h
new file mode 100644
index 0000000000..2b59492501
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/FreeRTOSConfig.h
@@ -0,0 +1,103 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#ifndef FREERTOS_CONFIG_H
+#define FREERTOS_CONFIG_H
+
+#include "riscv-virt.h"
+
+/*-----------------------------------------------------------
+ * Application specific definitions.
+ *
+ * These definitions should be adjusted for your particular hardware and
+ * application requirements.
+ *
+ * THESE PARAMETERS ARE DESCRIBED WITHIN THE 'CONFIGURATION' SECTION OF THE
+ * FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE.
+ *
+ * See http://www.freertos.org/a00110.html.
+ *----------------------------------------------------------*/
+
+/* See https://www.freertos.org/Using-FreeRTOS-on-RISC-V.html */
+#define configMTIME_BASE_ADDRESS		( CLINT_ADDR + CLINT_MTIME )
+#define configMTIMECMP_BASE_ADDRESS		( CLINT_ADDR + CLINT_MTIMECMP )
+
+#define configUSE_PREEMPTION			1
+#define configUSE_IDLE_HOOK				0
+#define configUSE_TICK_HOOK				1
+#define configCPU_CLOCK_HZ				( 1000000 )
+#define configTICK_RATE_HZ				( ( TickType_t ) 10 )
+#define configMAX_PRIORITIES			( 7 )
+#define configMINIMAL_STACK_SIZE		( ( unsigned short ) 512 )
+#define configTOTAL_HEAP_SIZE			( ( size_t ) 64500 )
+#define configMAX_TASK_NAME_LEN			( 16 )
+#define configUSE_TRACE_FACILITY		0
+#define configUSE_16_BIT_TICKS			0
+#define configIDLE_SHOULD_YIELD			0
+#define configUSE_MUTEXES				1
+#define configQUEUE_REGISTRY_SIZE		8
+#define configCHECK_FOR_STACK_OVERFLOW	2
+#define configUSE_RECURSIVE_MUTEXES		1
+#define configUSE_MALLOC_FAILED_HOOK	1
+#define configUSE_APPLICATION_TASK_TAG	0
+#define configUSE_COUNTING_SEMAPHORES	1
+#define configGENERATE_RUN_TIME_STATS	0
+#define configUSE_PORT_OPTIMISED_TASK_SELECTION 1
+
+/* Co-routine definitions. */
+#define configUSE_CO_ROUTINES 			0
+#define configMAX_CO_ROUTINE_PRIORITIES ( 2 )
+
+/* Software timer definitions. */
+#define configUSE_TIMERS				1
+#define configTIMER_TASK_PRIORITY		( configMAX_PRIORITIES - 1 )
+#define configTIMER_QUEUE_LENGTH		6
+#define configTIMER_TASK_STACK_DEPTH	( 110 )
+
+/* RISC-V definitions. */
+#define configISR_STACK_SIZE_WORDS		2048
+
+/* Task priorities.  Allow these to be overridden. */
+#ifndef uartPRIMARY_PRIORITY
+	#define uartPRIMARY_PRIORITY		( configMAX_PRIORITIES - 3 )
+#endif
+
+/* Set the following definitions to 1 to include the API function, or zero
+to exclude the API function. */
+#define INCLUDE_vTaskPrioritySet			1
+#define INCLUDE_uxTaskPriorityGet			1
+#define INCLUDE_vTaskDelete					1
+#define INCLUDE_vTaskCleanUpResources		1
+#define INCLUDE_vTaskSuspend				1
+#define INCLUDE_vTaskDelayUntil				1
+#define INCLUDE_vTaskDelay					1
+#define INCLUDE_eTaskGetState				1
+#define INCLUDE_xTimerPendFunctionCall		1
+#define INCLUDE_xTaskAbortDelay				1
+#define INCLUDE_xTaskGetHandle				1
+#define INCLUDE_xSemaphoreGetMutexHolder	1
+
+#endif /* FREERTOS_CONFIG_H */
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/Makefile b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/Makefile
new file mode 100644
index 0000000000..929da07efd
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/Makefile
@@ -0,0 +1,82 @@
+XLEN ?= 32
+CROSS   = riscv$(XLEN)-unknown-elf-
+CC      = $(CROSS)gcc
+OBJCOPY = $(CROSS)objcopy
+ARCH    = $(CROSS)ar
+DEBUG ?= 0
+
+ifeq ($(XLEN), 64)
+    MARCH = rv64ima
+    MABI = lp64
+	STACK_SIZE = 600
+else
+    MARCH = rv32ima
+    MABI = ilp32
+	STACK_SIZE = 300
+endif
+
+BUILD_DIR       = build
+RTOS_SOURCE_DIR = $(abspath ../../Source)
+DEMO_SOURCE_DIR = $(abspath ../Common/Minimal)
+
+CPPFLAGS = \
+	-D__riscv_float_abi_soft \
+	-DportasmHANDLE_INTERRUPT=handle_trap \
+	-I . -I ../Common/include \
+	-I $(RTOS_SOURCE_DIR)/include \
+	-I $(RTOS_SOURCE_DIR)/portable/GCC/RISC-V \
+	-I $(RTOS_SOURCE_DIR)/portable/GCC/RISC-V/chip_specific_extensions/RV32I_CLINT_no_extensions
+CFLAGS  = -march=$(MARCH) -mabi=$(MABI) -mcmodel=medany \
+	-Wall \
+	-fmessage-length=0 \
+	-ffunction-sections \
+	-fdata-sections \
+	-fno-builtin-printf
+ASFLAGS = -march=$(MARCH) -mabi=$(MABI) -mcmodel=medany
+LDFLAGS = -nostartfiles -Tfake_rom.lds \
+	-Xlinker --gc-sections \
+	-Xlinker --defsym=__stack_size=$(STACK_SIZE)
+
+ifeq ($(DEBUG), 1)
+    CFLAGS += -Og -ggdb3
+else
+    CFLAGS += -Os
+endif
+
+SRCS = main.c main_blinky.c riscv-virt.c htif.c \
+	$(DEMO_SOURCE_DIR)/EventGroupsDemo.c \
+	$(DEMO_SOURCE_DIR)/TaskNotify.c \
+	$(DEMO_SOURCE_DIR)/TimerDemo.c \
+	$(DEMO_SOURCE_DIR)/blocktim.c \
+	$(DEMO_SOURCE_DIR)/dynamic.c \
+	$(DEMO_SOURCE_DIR)/recmutex.c \
+	$(RTOS_SOURCE_DIR)/event_groups.c \
+	$(RTOS_SOURCE_DIR)/list.c \
+	$(RTOS_SOURCE_DIR)/queue.c \
+	$(RTOS_SOURCE_DIR)/stream_buffer.c \
+	$(RTOS_SOURCE_DIR)/tasks.c \
+	$(RTOS_SOURCE_DIR)/timers.c \
+	$(RTOS_SOURCE_DIR)/portable/MemMang/heap_4.c \
+	$(RTOS_SOURCE_DIR)/portable/GCC/RISC-V/port.c
+
+ASMS = start.S \
+	$(RTOS_SOURCE_DIR)/portable/GCC/RISC-V/portASM.S
+
+OBJS = $(SRCS:%.c=$(BUILD_DIR)/%.o) $(ASMS:%.S=$(BUILD_DIR)/%.o)
+DEPS = $(SRCS:%.c=$(BUILD_DIR)/%.d) $(ASMS:%.S=$(BUILD_DIR)/%.d)
+
+$(BUILD_DIR)/RTOSDemo.axf: $(OBJS) fake_rom.lds Makefile
+	$(CC) $(LDFLAGS) $(OBJS) -o $@
+
+$(BUILD_DIR)/%.o: %.c Makefile
+	@mkdir -p $(@D)
+	$(CC) $(CPPFLAGS) $(CFLAGS) -MMD -MP -c $< -o $@
+
+$(BUILD_DIR)/%.o: %.S Makefile
+	@mkdir -p $(@D)
+	$(CC) $(CPPFLAGS) $(ASFLAGS) -MMD -MP -c $< -o $@
+
+clean:
+	rm -rf $(BUILD_DIR)
+
+-include $(DEPS)
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/README.md b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/README.md
new file mode 100644
index 0000000000..03e4499fb7
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/README.md
@@ -0,0 +1,106 @@
+# Emulating generic RISC-V 32bit machine on spike
+
+## Requirements
+
+1. GNU RISC-V toolchains (tested on Crosstool-NG)
+2. spike from https://github.com/riscv/riscv-isa-sim
+3. OpenOCD from https://github.com/riscv/riscv-openocd
+
+## How to build toolchain
+
+Clone the Crosstool-NG and build.
+
+```
+$ git clone https://github.com/crosstool-ng/crosstool-ng
+$ cd crosstool-ng
+$ ./bootstrap
+$ ./configure --enable-local
+$ make
+$ ./ct-ng menuconfig
+```
+
+For RV32 builds, change the following configs:
+
+```
+CT_EXPERIMENTAL=y
+CT_ARCH_RISCV=y
+CT_ARCH_64=n
+CT_ARCH_ARCH=rv32ima
+CT_ARCH_ABI=ilp32
+CT_TARGET_CFLAGS="-mcmodel=medany"
+CT_TARGET_LDFLAGS="-mcmodel=medany"
+CT_MULTILIB=y
+CT_DEBUG_GDB=y
+```
+
+For RV64 builds, change the following configs:
+
+```
+CT_EXPERIMENTAL=y
+CT_ARCH_RISCV=y
+CT_ARCH_64=y
+CT_ARCH_ARCH=rv32ima
+CT_ARCH_ABI=ilp32
+CT_TARGET_CFLAGS="-mcmodel=medany"
+CT_TARGET_LDFLAGS="-mcmodel=medany"
+CT_MULTILIB=y
+CT_DEBUG_GDB=y
+```
+
+Build the GNU toolchain for RISC-V.
+
+```
+$ ./ct-ng build
+```
+
+A toolchain is installed at ~/x-tools/riscv64-unknown-elf directory.
+
+
+## How to build
+
+Add path of toolchain that is described above section.
+
+```
+$ export PATH=~/x-tools/riscv64-unknown-elf/bin:$PATH
+```
+
+To build, simply run `make`. If you want a debug build, pass `DEBUG=1`. If
+you want an RV64 build, pass `XLEN=64`.
+
+The resulting executable file is ./build/RTOSDemo.axf.
+
+## How to run
+
+RV32:
+```
+$ spike -p1 --isa RV32IMA -m0x80000000:0x10000000 --rbb-port 9824 \
+        ./build/RTOSDemo.axf
+```
+
+RV64:
+```
+$ spike -p1 --isa RV64IMA -m0x80000000:0x10000000 --rbb-port 9824 \
+        ./build/RTOSDemo.axf
+```
+
+## How to debug with gdb
+
+Start OpenOCD in one terminal:
+```
+$ openocd -f spike-1.cfg
+```
+
+Start gdb in another:
+```
+$ riscv64-unknown-elf-gdb ./build/RTOSDemo.axf
+...
+(gdb) target extended-remote localhost:3333
+...
+(gdb) info threads
+```
+
+(As of 3/22/2021 OpenOCD's RISC-V FreeRTOS awareness is still incomplete.)
+
+## Description
+
+This demo starts separate transmit and receive threads. The transmit thread sends integers through a queue. Both threads print out what they're sending/receiving using HTIF.
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/fake_rom.lds b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/fake_rom.lds
new file mode 100644
index 0000000000..b63fad8f05
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/fake_rom.lds
@@ -0,0 +1,117 @@
+OUTPUT_ARCH( "riscv" )
+ENTRY( _start )
+
+MEMORY
+{
+	/* Fake ROM area */
+	rom (rxa) : ORIGIN = 0x80000000, LENGTH = 512K
+	ram (wxa) : ORIGIN = 0x80080000, LENGTH = 512K
+}
+
+SECTIONS
+{
+	.init :
+	{
+		_text = .;
+		KEEP (*(SORT_NONE(.init)))
+	} >rom AT>rom
+	
+	.text :
+	{
+		*(.text.unlikely .text.unlikely.*)
+		*(.text.startup .text.startup.*)
+		*(.text .text.*)
+		*(.gnu.linkonce.t.*)
+	} >rom AT>rom
+	
+	.fini :
+	{
+		KEEP (*(SORT_NONE(.fini)))
+		_etext = .;
+	} >rom AT>rom
+
+	.rodata.align :
+	{
+		. = ALIGN(4);
+		_rodata = .;
+	} >rom AT>rom
+
+	.rodata.start :
+	{
+		_rodata_lma = LOADADDR(.rodata.start);
+	} >rom AT>rom
+
+	.rodata :
+	{
+		*(.rdata)
+		*(.rodata .rodata.*)
+		*(.gnu.linkonce.r.*)
+
+		. = ALIGN(4);
+		_erodata = .;
+	} >rom AT>rom
+
+	.data.align :
+	{
+		. = ALIGN(4);
+		_data = .;
+	} >ram AT>rom
+
+	.data.start :
+	{
+		_data_lma = LOADADDR(.data.start);
+	} >ram AT>rom
+
+	.data :
+	{
+		*(.data .data.*)
+		*(.gnu.linkonce.d.*)
+		. = ALIGN(8);
+		PROVIDE( __global_pointer$ = . + 0x800 );
+		*(.sdata .sdata.*)
+		*(.sdata2 .sdata2.*)
+		*(.gnu.linkonce.s.*)
+		. = ALIGN(8);
+		*(.srodata.cst16)
+		*(.srodata.cst8)
+		*(.srodata.cst4)
+		*(.srodata.cst2)
+		*(.srodata .srodata.*)
+
+		. = ALIGN(4);
+		_edata = .;
+	} >ram AT>rom
+
+	.bss.align :
+	{
+		. = ALIGN(4);
+		_bss = .;
+	} >ram AT>rom
+
+	.bss.start :
+	{
+		_bss_lma = LOADADDR(.bss.start);
+	} >ram AT>rom
+
+	.bss :
+	{
+		*(.sbss*)
+		*(.gnu.linkonce.sb.*)
+		*(.bss .bss.*)
+		*(.gnu.linkonce.b.*)
+		*(COMMON)
+
+		. = ALIGN(4);
+		_ebss = .;
+	} >ram AT>rom
+
+	. = ALIGN(8);
+	_end = .;
+
+	.stack :
+	{
+		. = ALIGN(16);
+		. += __stack_size;
+		_stack_top = .;
+	} >ram AT>ram
+}
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.c b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.c
new file mode 100644
index 0000000000..74c30c23cc
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.c
@@ -0,0 +1,142 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2010-2020, The Regents of the University of California
+ * (Regents).  All Rights Reserved.
+ */
+
+#include <htif.h>
+
+#define HTIF_DATA_BITS		48
+#define HTIF_DATA_MASK		((1ULL << HTIF_DATA_BITS) - 1)
+#define HTIF_DATA_SHIFT		0
+#define HTIF_CMD_BITS		8
+#define HTIF_CMD_MASK		((1ULL << HTIF_CMD_BITS) - 1)
+#define HTIF_CMD_SHIFT		48
+#define HTIF_DEV_BITS		8
+#define HTIF_DEV_MASK		((1ULL << HTIF_DEV_BITS) - 1)
+#define HTIF_DEV_SHIFT		56
+
+#define HTIF_DEV_SYSTEM		0
+#define HTIF_DEV_CONSOLE	1
+
+#define HTIF_CONSOLE_CMD_GETC	0
+#define HTIF_CONSOLE_CMD_PUTC	1
+
+#if __riscv_xlen == 64
+# define TOHOST_CMD(dev, cmd, payload) \
+	(((uint64_t)(dev) << HTIF_DEV_SHIFT) | \
+	 ((uint64_t)(cmd) << HTIF_CMD_SHIFT) | \
+	 (uint64_t)(payload))
+#else
+# define TOHOST_CMD(dev, cmd, payload) ({ \
+  if ((dev) || (cmd)) __builtin_trap(); \
+  (payload); })
+#endif
+#define FROMHOST_DEV(fromhost_value) \
+	((uint64_t)((fromhost_value) >> HTIF_DEV_SHIFT) & HTIF_DEV_MASK)
+#define FROMHOST_CMD(fromhost_value) \
+	((uint64_t)((fromhost_value) >> HTIF_CMD_SHIFT) & HTIF_CMD_MASK)
+#define FROMHOST_DATA(fromhost_value) \
+	((uint64_t)((fromhost_value) >> HTIF_DATA_SHIFT) & HTIF_DATA_MASK)
+
+#define PK_SYS_write 64
+
+volatile uint64_t tohost __attribute__((section(".htif")));
+volatile uint64_t fromhost __attribute__((section(".htif")));
+static int htif_console_buf;
+
+static void __check_fromhost()
+{
+	uint64_t fh = fromhost;
+	if (!fh)
+		return;
+	fromhost = 0;
+
+	/* this should be from the console */
+	if (FROMHOST_DEV(fh) != HTIF_DEV_CONSOLE)
+		__builtin_trap();
+	switch (FROMHOST_CMD(fh)) {
+		case HTIF_CONSOLE_CMD_GETC:
+			htif_console_buf = 1 + (uint8_t)FROMHOST_DATA(fh);
+			break;
+		case HTIF_CONSOLE_CMD_PUTC:
+			break;
+		default:
+			__builtin_trap();
+	}
+}
+
+static void __set_tohost(uint64_t dev, uint64_t cmd, uint64_t data)
+{
+	while (tohost)
+		__check_fromhost();
+	tohost = TOHOST_CMD(dev, cmd, data);
+}
+
+#if __riscv_xlen == 32
+static void do_tohost_fromhost(uint64_t dev, uint64_t cmd, uint64_t data)
+{
+	__set_tohost(HTIF_DEV_SYSTEM, cmd, data);
+
+	while (1) {
+		uint64_t fh = fromhost;
+		if (fh) {
+			if (FROMHOST_DEV(fh) == HTIF_DEV_SYSTEM &&
+			    FROMHOST_CMD(fh) == cmd) {
+				fromhost = 0;
+				break;
+			}
+			__check_fromhost();
+		}
+	}
+}
+
+void htif_putc(char ch)
+{
+	/* HTIF devices are not supported on RV32, so do a proxy write call */
+	volatile uint64_t magic_mem[8];
+	magic_mem[0] = PK_SYS_write;
+	magic_mem[1] = HTIF_DEV_CONSOLE;
+	magic_mem[2] = (uint64_t)(uintptr_t)&ch;
+	magic_mem[3] = HTIF_CONSOLE_CMD_PUTC;
+	do_tohost_fromhost(HTIF_DEV_SYSTEM, 0, (uint64_t)(uintptr_t)magic_mem);
+}
+#else
+void htif_putc(char ch)
+{
+	__set_tohost(HTIF_DEV_CONSOLE, HTIF_CONSOLE_CMD_PUTC, ch);
+}
+#endif
+
+int htif_getc(void)
+{
+	int ch;
+
+#if __riscv_xlen == 32
+	/* HTIF devices are not supported on RV32 */
+	return -1;
+#endif
+
+	__check_fromhost();
+	ch = htif_console_buf;
+	if (ch >= 0) {
+		htif_console_buf = -1;
+		__set_tohost(HTIF_DEV_CONSOLE, HTIF_CONSOLE_CMD_GETC, 0);
+	}
+
+	return ch - 1;
+}
+
+int htif_system_reset_check(uint32_t type, uint32_t reason)
+{
+	return 1;
+}
+
+void htif_system_reset(uint32_t type, uint32_t reason)
+{
+	while (1) {
+		fromhost = 0;
+		tohost = 1;
+	}
+}
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.h b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.h
new file mode 100644
index 0000000000..1b08d365b8
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/htif.h
@@ -0,0 +1,21 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2010-2020, The Regents of the University of California
+ * (Regents).  All Rights Reserved.
+ */
+
+#ifndef __HTIF_H__
+#define __HTIF_H__
+
+#include <stdint.h>
+
+void htif_putc(char ch);
+
+int htif_getc(void);
+
+int htif_system_reset_check(uint32_t type, uint32_t reason);
+
+void htif_system_reset(uint32_t type, uint32_t reason);
+
+#endif
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main.c b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main.c
new file mode 100644
index 0000000000..1d4b78f329
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main.c
@@ -0,0 +1,116 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+/* FreeRTOS kernel includes. */
+#include <FreeRTOS.h>
+#include <task.h>
+
+/* Run a simple demo just prints 'Blink' */
+#define DEMO_BLINKY	1
+
+void vApplicationMallocFailedHook( void );
+void vApplicationIdleHook( void );
+void vApplicationStackOverflowHook( TaskHandle_t pxTask, char *pcTaskName );
+void vApplicationTickHook( void );
+
+int main_blinky( void );
+
+/*-----------------------------------------------------------*/
+
+int main( void )
+{
+	int ret;
+
+#if defined(DEMO_BLINKY)
+	ret = main_blinky();
+#else
+#error "Please add or select demo."
+#endif
+
+	return ret;
+}
+
+/*-----------------------------------------------------------*/
+
+void vApplicationMallocFailedHook( void )
+{
+	/* vApplicationMallocFailedHook() will only be called if
+	configUSE_MALLOC_FAILED_HOOK is set to 1 in FreeRTOSConfig.h.  It is a hook
+	function that will get called if a call to pvPortMalloc() fails.
+	pvPortMalloc() is called internally by the kernel whenever a task, queue,
+	timer or semaphore is created.  It is also called by various parts of the
+	demo application.  If heap_1.c or heap_2.c are used, then the size of the
+	heap available to pvPortMalloc() is defined by configTOTAL_HEAP_SIZE in
+	FreeRTOSConfig.h, and the xPortGetFreeHeapSize() API function can be used
+	to query the size of free heap space that remains (although it does not
+	provide information on how the remaining heap might be fragmented). */
+	taskDISABLE_INTERRUPTS();
+	for( ;; );
+}
+/*-----------------------------------------------------------*/
+
+void vApplicationIdleHook( void )
+{
+	/* vApplicationIdleHook() will only be called if configUSE_IDLE_HOOK is set
+	to 1 in FreeRTOSConfig.h.  It will be called on each iteration of the idle
+	task.  It is essential that code added to this hook function never attempts
+	to block in any way (for example, call xQueueReceive() with a block time
+	specified, or call vTaskDelay()).  If the application makes use of the
+	vTaskDelete() API function (as this demo application does) then it is also
+	important that vApplicationIdleHook() is permitted to return to its calling
+	function, because it is the responsibility of the idle task to clean up
+	memory allocated by the kernel to any task that has since been deleted. */
+}
+/*-----------------------------------------------------------*/
+
+void vApplicationStackOverflowHook( TaskHandle_t pxTask, char *pcTaskName )
+{
+	( void ) pcTaskName;
+	( void ) pxTask;
+
+	/* Run time stack overflow checking is performed if
+	configCHECK_FOR_STACK_OVERFLOW is defined to 1 or 2.  This hook
+	function is called if a stack overflow is detected. */
+	taskDISABLE_INTERRUPTS();
+	for( ;; );
+}
+/*-----------------------------------------------------------*/
+
+void vApplicationTickHook( void )
+{
+}
+/*-----------------------------------------------------------*/
+
+void vAssertCalled( void )
+{
+volatile uint32_t ulSetTo1ToExitFunction = 0;
+
+	taskDISABLE_INTERRUPTS();
+	while( ulSetTo1ToExitFunction != 1 )
+	{
+		__asm volatile( "NOP" );
+	}
+}
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main_blinky.c b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main_blinky.c
new file mode 100644
index 0000000000..f2604f8b2a
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/main_blinky.c
@@ -0,0 +1,137 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+/* FreeRTOS kernel includes. */
+#include <FreeRTOS.h>
+#include <task.h>
+#include <queue.h>
+
+#include <stdio.h>
+
+#include "riscv-virt.h"
+
+/* Priorities used by the tasks. */
+#define mainQUEUE_RECEIVE_TASK_PRIORITY		( tskIDLE_PRIORITY + 2 )
+#define	mainQUEUE_SEND_TASK_PRIORITY		( tskIDLE_PRIORITY + 1 )
+
+/* The rate at which data is sent to the queue.  The 200ms value is converted
+to ticks using the pdMS_TO_TICKS() macro. */
+#define mainQUEUE_SEND_FREQUENCY_MS			pdMS_TO_TICKS( 1000 )
+
+/* The maximum number items the queue can hold.  The priority of the receiving
+task is above the priority of the sending task, so the receiving task will
+preempt the sending task and remove the queue items each time the sending task
+writes to the queue.  Therefore the queue will never have more than one item in
+it at any time, and even with a queue length of 1, the sending task will never
+find the queue full. */
+#define mainQUEUE_LENGTH					( 1 )
+
+/*-----------------------------------------------------------*/
+
+/* The queue used by both tasks. */
+static QueueHandle_t xQueue = NULL;
+
+/*-----------------------------------------------------------*/
+
+static void prvQueueSendTask( void *pvParameters )
+{
+	TickType_t xNextWakeTime;
+	unsigned long ulValueToSend = 0UL;
+
+	/* Remove compiler warning about unused parameter. */
+	( void ) pvParameters;
+
+	/* Initialise xNextWakeTime - this only needs to be done once. */
+	xNextWakeTime = xTaskGetTickCount();
+
+	for( ;; )
+	{
+		/* Place this task in the blocked state until it is time to run again. */
+		vTaskDelayUntil( &xNextWakeTime, mainQUEUE_SEND_FREQUENCY_MS );
+
+		ulValueToSend++;
+
+		char buf[40];
+		sprintf( buf, "%d: %s: send %ld", xGetCoreID(),
+				pcTaskGetName( xTaskGetCurrentTaskHandle() ),
+				ulValueToSend );
+		vSendString( buf );
+
+		/* 0 is used as the block time so the sending operation will not block -
+		 * it shouldn't need to block as the queue should always be empty at
+		 * this point in the code. */
+		xQueueSend( xQueue, &ulValueToSend, 0U );
+	}
+}
+
+/*-----------------------------------------------------------*/
+
+static void prvQueueReceiveTask( void *pvParameters )
+{
+	/* Remove compiler warning about unused parameter. */
+	( void ) pvParameters;
+
+	for( ;; )
+	{
+
+		unsigned long ulReceivedValue;
+		/* Wait until something arrives in the queue - this task will block
+		indefinitely provided INCLUDE_vTaskSuspend is set to 1 in
+		FreeRTOSConfig.h. */
+		xQueueReceive( xQueue, &ulReceivedValue, portMAX_DELAY );
+
+		/*  To get here something must have been received from the queue. */
+		char buf[40];
+		sprintf( buf, "%d: %s: received %ld", xGetCoreID(),
+				pcTaskGetName( xTaskGetCurrentTaskHandle() ),
+				ulReceivedValue );
+		vSendString( buf );
+	}
+}
+
+/*-----------------------------------------------------------*/
+
+int main_blinky( void )
+{
+	vSendString( "Hello FreeRTOS!" );
+
+	/* Create the queue. */
+	xQueue = xQueueCreate( mainQUEUE_LENGTH, sizeof( unsigned long ) );
+
+	if( xQueue != NULL )
+	{
+		/* Start the two tasks as described in the comments at the top of this
+		file. */
+		xTaskCreate( prvQueueReceiveTask, "Rx", configMINIMAL_STACK_SIZE * 2U, NULL,
+					mainQUEUE_RECEIVE_TASK_PRIORITY, NULL );
+		xTaskCreate( prvQueueSendTask, "Tx", configMINIMAL_STACK_SIZE * 2U, NULL,
+					mainQUEUE_SEND_TASK_PRIORITY, NULL );
+	}
+
+	vTaskStartScheduler();
+
+	return 0;
+}
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-reg.h b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-reg.h
new file mode 100644
index 0000000000..f199f21547
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-reg.h
@@ -0,0 +1,42 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#ifndef RISCV_REG_H_
+#define RISCV_REG_H_
+
+#if __riscv_xlen == 32
+#define REGSIZE		4
+#define REGSHIFT	2
+#define LOAD		lw
+#define STOR		sw
+#elif __riscv_xlen == 64
+#define REGSIZE		8
+#define REGSHIFT	3
+#define LOAD		ld
+#define STOR		sd
+#endif /* __riscv_xlen */
+
+#endif /* RISCV_REG_H_ */
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.c b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.c
new file mode 100644
index 0000000000..a1fd73b22f
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.c
@@ -0,0 +1,60 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#include <FreeRTOS.h>
+
+#include <string.h>
+
+#include "riscv-virt.h"
+#include "htif.h"
+
+int xGetCoreID( void )
+{
+int id;
+
+	__asm ("csrr %0, mhartid" : "=r" ( id ) );
+
+	return id;
+}
+
+void vSendString( const char *s )
+{
+	portENTER_CRITICAL();
+
+	while (*s) {
+		htif_putc(*s);
+		s++;
+	}
+	htif_putc('\n');
+
+	portEXIT_CRITICAL();
+}
+
+void handle_trap(void)
+{
+	while (1)
+		;
+}
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.h b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.h
new file mode 100644
index 0000000000..c22d9a6640
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/riscv-virt.h
@@ -0,0 +1,52 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#ifndef RISCV_VIRT_H_
+#define RISCV_VIRT_H_
+
+#include "riscv-reg.h"
+
+#ifdef __ASSEMBLER__
+#define CONS(NUM, TYPE)NUM
+#else
+#define CONS(NUM, TYPE)NUM##TYPE
+#endif /* __ASSEMBLER__ */
+
+#define PRIM_HART			0
+
+#define CLINT_ADDR			CONS(0x02000000, UL)
+#define CLINT_MSIP			CONS(0x0000, UL)
+#define CLINT_MTIMECMP		CONS(0x4000, UL)
+#define CLINT_MTIME			CONS(0xbff8, UL)
+
+#ifndef __ASSEMBLER__
+
+int xGetCoreID( void );
+void vSendString( const char * s );
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* RISCV_VIRT_H_ */
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/spike-1.cfg b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/spike-1.cfg
new file mode 100644
index 0000000000..572a94ea27
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/spike-1.cfg
@@ -0,0 +1,33 @@
+adapter_khz     10000
+
+interface remote_bitbang
+remote_bitbang_host localhost
+remote_bitbang_port 9824
+
+set _CHIPNAME riscv
+jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x10e31913
+
+set _TARGETNAME $_CHIPNAME.cpu
+target create $_TARGETNAME riscv -chain-position $_TARGETNAME -rtos auto
+#target create $_TARGETNAME riscv -chain-position $_TARGETNAME
+$_TARGETNAME configure -work-area-phys 0x80000000 -work-area-size 8096 -work-area-backup 1
+
+
+gdb_report_data_abort enable
+gdb_report_register_access_error enable
+
+# Expose an unimplemented CSR so we can test non-existent register access
+# behavior.
+riscv expose_csrs 2288
+riscv expose_custom 1,12345-12348
+
+init
+
+set challenge [riscv authdata_read]
+riscv authdata_write [expr $challenge + 1]
+
+halt
+
+reg mstatus 0
+
+arm semihosting enable
diff --git a/FreeRTOS/Demo/RISC-V-spike-htif_GCC/start.S b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/start.S
new file mode 100644
index 0000000000..08a5114b48
--- /dev/null
+++ b/FreeRTOS/Demo/RISC-V-spike-htif_GCC/start.S
@@ -0,0 +1,84 @@
+/*
+ * FreeRTOS V202012.00
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+#include "riscv-virt.h"
+
+	.section .init
+	.globl _start
+	.type _start,@function
+_start:
+	.cfi_startproc
+	.cfi_undefined ra
+.option push
+.option norelax
+	la  gp, __global_pointer$
+.option pop
+
+	// Continue primary hart
+	csrr a0, mhartid
+	li   a1, PRIM_HART
+	bne  a0, a1, secondary
+
+	// Primary hart
+	la sp, _stack_top
+
+	// Load data section
+	la a0, _data_lma
+	la a1, _data
+	la a2, _edata
+	bgeu a1, a2, 2f
+1:
+	LOAD t0, (a0)
+	STOR t0, (a1)
+	addi a0, a0, REGSIZE
+	addi a1, a1, REGSIZE
+	bltu a1, a2, 1b
+2:
+
+	// Clear bss section
+	la a0, _bss
+	la a1, _ebss
+	bgeu a0, a1, 2f
+1:
+	STOR zero, (a0)
+	addi a0, a0, REGSIZE
+	bltu a0, a1, 1b
+2:
+
+	// argc, argv, envp is 0
+	li  a0, 0
+	li  a1, 0
+	li  a2, 0
+	jal main
+1:
+	wfi
+	j 1b
+
+secondary:
+	// TODO: Multicore is not supported
+	wfi
+	j secondary
+	.cfi_endproc