Merge branch 'for-next/risc-V'

38 files changed, 1317 insertions, 1 deletions

diff --git a/Documentation/boards/riscv.rst b/Documentation/boards/riscv.rst
new file mode 100644
index 0000000000..c7fa52aadb
--- /dev/null
+++ b/Documentation/boards/riscv.rst
@@ -0,0 +1,91 @@
+RISC-V
+======
+
+Running RISC-V barebox on qemu
+------------------------------
+
+Obtain RISC-V GCC/Newlib Toolchain,
+see https://github.com/riscv/riscv-tools/blob/master/README.md
+for details. The ``build.sh`` script from ``riscv-tools`` should
+create toolchain.
+
+Next compile qemu emulator::
+
+  $ git clone -b 20180409.erizo https://github.com/miet-riscv-workgroup/riscv-qemu
+  $ cd riscv-qemu
+  $ cap="no" ./configure \
+    --extra-cflags="-Wno-maybe-uninitialized" \
+    --audio-drv-list="" \
+    --disable-attr \
+    --disable-blobs \
+    --disable-bluez \
+    --disable-brlapi \
+    --disable-curl \
+    --disable-curses \
+    --disable-docs \
+    --disable-kvm \
+    --disable-spice \
+    --disable-sdl \
+    --disable-vde \
+    --disable-vnc-sasl \
+    --disable-werror \
+    --enable-trace-backend=simple \
+    --disable-stack-protector \
+    --target-list=riscv32-softmmu,riscv64-softmmu
+  $ make
+
+
+Next compile barebox::
+
+  $ make erizo_generic_defconfig ARCH=riscv
+  ...
+  $ make ARCH=riscv CROSS_COMPILE=<path to your riscv toolchain>/riscv32-unknown-elf-
+
+Run barebox::
+
+  $ <path to riscv-qemu source>/riscv32-softmmu/qemu-system-riscv32 \
+      -nographic -M erizo -bios <path to barebox sources >/barebox.bin \
+      -serial stdio -monitor none -trace file=/dev/null
+  Switch to console [cs0]
+  
+  
+  barebox 2018.12.0-00148-g60e49c4e16 #1 Tue Dec 18 01:12:29 MSK 2018
+  
+  
+  Board: generic Erizo SoC board
+  malloc space: 0x80100000 -> 0x801fffff (size 1 MiB)
+  running /env/bin/init...
+  /env/bin/init not found
+  barebox:/
+
+
+Running RISC-V barebox on DE0-Nano FPGA board
+---------------------------------------------
+
+See https://github.com/open-design/riscv-soc-cores/ for instructions
+on DE0-Nano bitstream generation and loading.
+
+Connect to board's UART with your favorite serial communication software
+(e.g. minicom) and check 'nmon> ' prompt (nmon runs from onchip ROM).
+
+Next close your communication software and use ./scripts/nmon-loader
+to load barebox image into board's DRAM, e.g.
+
+  # ./scripts/nmon-loader barebox.erizo.nmon /dev/ttyUSB0 115200
+
+Wait several munutes for 'nmon> ' prompt.
+
+Next, start barebox from DRAM:
+
+  nmon> g 80000000
+  Switch to console [cs0]
+  
+  
+  barebox 2018.12.0-00148-g60e49c4e16 #1 Tue Dec 18 01:12:29 MSK 2018
+  
+  
+  Board: generic Erizo SoC board
+  malloc space: 0x80100000 -> 0x801fffff (size 1 MiB)
+  running /env/bin/init...
+  /env/bin/init not found
+  barebox:/
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
new file mode 100644
index 0000000000..c435cc8a31
--- /dev/null
+++ b/arch/riscv/Kconfig
@@ -0,0 +1,91 @@
+config RISCV
+	def_bool y
+	select GENERIC_FIND_NEXT_BIT
+	select HAVE_CONFIGURABLE_MEMORY_LAYOUT
+	select HAVE_CONFIGURABLE_TEXT_BASE
+	select GPIOLIB
+	select OFTREE
+	select COMMON_CLK
+	select COMMON_CLK_OF_PROVIDER
+	select CLKDEV_LOOKUP
+
+config ARCH_TEXT_BASE
+	hex
+	default 0x0
+
+menu "Machine selection"
+
+choice
+	prompt "System type"
+	default MACH_ERIZO
+
+config MACH_ERIZO
+	bool "erizo family"
+	select HAS_DEBUG_LL
+	select HAS_NMON
+
+endchoice
+
+choice
+	prompt "Base ISA"
+	default ARCH_RV32I
+
+config ARCH_RV32I
+	bool "RV32I"
+	select CPU_SUPPORTS_32BIT_KERNEL
+	select GENERIC_LIB_ASHLDI3
+	select GENERIC_LIB_ASHRDI3
+	select GENERIC_LIB_LSHRDI3
+
+endchoice
+
+config CPU_SUPPORTS_32BIT_KERNEL
+	bool
+
+choice
+	prompt "barebox code model"
+	default 32BIT
+
+config 32BIT
+	bool "32-bit barebox"
+	depends on CPU_SUPPORTS_32BIT_KERNEL
+	help
+	  Select this option to build a 32-bit barebox.
+
+endchoice
+
+config BUILTIN_DTB
+	bool "link a DTB into the barebox image"
+	depends on OFTREE
+
+config BUILTIN_DTB_NAME
+	string "DTB to build into the barebox image"
+	depends on BUILTIN_DTB
+
+source arch/riscv/mach-erizo/Kconfig
+
+endmenu
+
+menu "RISC-V specific settings"
+
+config HAS_NMON
+	bool
+
+config NMON
+	bool "nmon"
+	depends on HAS_NMON
+	depends on DEBUG_LL
+	help
+	  Say yes here to add the nmon to pbl.
+	  nmon -- nano-monitor program for the RISC-V processors.
+	  It can operate with NO working RAM, using only
+	  the processor registers.
+
+config NMON_HELP
+	bool "nmon help message"
+	depends on NMON
+	help
+	  Say yes here to get the nmon commands message on
+	  every nmon start.
+
+endmenu
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
new file mode 100644
index 0000000000..643c0bc8eb
--- /dev/null
+++ b/arch/riscv/Makefile
@@ -0,0 +1,67 @@
+CPPFLAGS += -fno-strict-aliasing
+
+ifeq ($(CONFIG_ARCH_RV32I),y)
+	cflags-y += -march=rv32im
+endif
+
+cflags-y += -fno-pic -pipe
+cflags-y += -Wall -Wstrict-prototypes \
+	-Wno-uninitialized -Wno-format -Wno-main -mcmodel=medany
+
+LDFLAGS += $(ldflags-y)
+LDFLAGS_barebox += -nostdlib
+
+machine-$(CONFIG_MACH_ERIZO)	:= erizo
+
+TEXT_BASE = $(CONFIG_TEXT_BASE)
+CPPFLAGS += -DTEXT_BASE=$(CONFIG_TEXT_BASE)
+
+ifndef CONFIG_MODULES
+# Add cleanup flags
+CPPFLAGS += -fdata-sections -ffunction-sections
+LDFLAGS_barebox += -static --gc-sections
+endif
+
+KBUILD_BINARY := barebox.bin
+
+machdirs := $(patsubst %,arch/riscv/mach-%/,$(machine-y))
+
+ifeq ($(KBUILD_SRC),)
+CPPFLAGS += $(patsubst %,-I%include,$(machdirs))
+else
+CPPFLAGS += $(patsubst %,-I$(srctree)/%include,$(machdirs))
+endif
+
+archprepare: maketools
+
+PHONY += maketools
+
+ifneq ($(machine-y),)
+MACH  := arch/riscv/mach-$(machine-y)/
+else
+MACH  :=
+endif
+
+common-y += $(MACH)
+common-y += arch/riscv/boot/
+common-y += arch/riscv/lib/
+
+common-$(CONFIG_OFTREE) += arch/riscv/dts/
+
+CPPFLAGS += $(cflags-y)
+CFLAGS += $(cflags-y)
+
+lds-y	:= arch/riscv/lib/barebox.lds
+
+CLEAN_FILES += arch/riscv/lib/barebox.lds
+
+ifeq ($(CONFIG_MACH_ERIZO),y)
+KBUILD_IMAGE := barebox.erizo.nmon
+endif
+
+quiet_cmd_erizo_nmon_image = MKIMAGE $@
+      cmd_erizo_nmon_image = $(srctree)/scripts/erizo-nmon-image $< $@ || \
+	echo "WARNING: Couldn't create erizo nmon image due to previous errors."
+
+barebox.erizo.nmon: $(KBUILD_BINARY) FORCE
+	$(call if_changed,erizo_nmon_image)
diff --git a/arch/riscv/boot/Makefile b/arch/riscv/boot/Makefile
new file mode 100644
index 0000000000..fd62cab8c1
--- /dev/null
+++ b/arch/riscv/boot/Makefile
@@ -0,0 +1,3 @@
+obj-y += start.o
+obj-y += main_entry.o
+obj-$(CONFIG_OFDEVICE) += dtb.o
diff --git a/arch/riscv/boot/dtb.c b/arch/riscv/boot/dtb.c
new file mode 100644
index 0000000000..5d73413a43
--- /dev/null
+++ b/arch/riscv/boot/dtb.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2016, 2018 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <common.h>
+#include <init.h>
+#include <of.h>
+
+extern char __dtb_start[];
+
+static int of_riscv_init(void)
+{
+	struct device_node *root;
+
+	root = of_get_root_node();
+	if (root)
+		return 0;
+
+	root = of_unflatten_dtb(__dtb_start);
+	if (!IS_ERR(root)) {
+		pr_debug("using internal DTB\n");
+		of_set_root_node(root);
+		if (IS_ENABLED(CONFIG_OFDEVICE))
+			of_probe();
+	}
+
+	return 0;
+}
+core_initcall(of_riscv_init);
diff --git a/arch/riscv/boot/main_entry.c b/arch/riscv/boot/main_entry.c
new file mode 100644
index 0000000000..f9c640c112
--- /dev/null
+++ b/arch/riscv/boot/main_entry.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2016 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <common.h>
+#include <memory.h>
+#include <asm-generic/memory_layout.h>
+#include <asm/sections.h>
+
+void main_entry(void);
+
+/**
+ * Called plainly from assembler code
+ *
+ * @note The C environment isn't initialized yet
+ */
+void main_entry(void)
+{
+	/* clear the BSS first */
+	memset(__bss_start, 0x00, __bss_stop - __bss_start);
+
+	mem_malloc_init((void *)MALLOC_BASE,
+			(void *)(MALLOC_BASE + MALLOC_SIZE - 1));
+
+	start_barebox();
+}
diff --git a/arch/riscv/boot/start.S b/arch/riscv/boot/start.S
new file mode 100644
index 0000000000..d1dbe48b7b
--- /dev/null
+++ b/arch/riscv/boot/start.S
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Startup Code for RISC-V CPU
+ *
+ * Copyright (C) 2016 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * based on coreboot/src/arch/riscv/bootblock.S
+ *      and barebox/arch/mips/boot/start.S
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <asm-generic/memory_layout.h>
+
+#include "mach/debug_ll.h"
+
+#include "asm/riscv_nmon.h"
+
+	.text
+	.section ".text_entry"
+	.align 2
+
+.globl _start
+_start:
+	debug_ll_ns16550_init
+
+	riscv_nmon
+
+	li	sp, STACK_BASE + STACK_SIZE
+
+	/* copy barebox to link location */
+
+	la	a0, _start	/* a0 <- _start actual address */
+	li	a1, CONFIG_TEXT_BASE	/* a1 <- _start link address */
+
+	beq	a0, a1, main_entry
+
+	la	a2, __bss_start
+
+#define LONGSIZE 4
+
+copy_loop:
+	/* copy from source address [a0] */
+	lw	t0, LONGSIZE * 0(a0)
+	lw	t1, LONGSIZE * 1(a0)
+	lw	t2, LONGSIZE * 2(a0)
+	lw	t3, LONGSIZE * 3(a0)
+	/* copy to target address [a1] */
+	sw	t0, LONGSIZE * 0(a1)
+	sw	t1, LONGSIZE * 1(a1)
+	sw	t2, LONGSIZE * 2(a1)
+	sw	t3, LONGSIZE * 3(a1)
+	addi	a0, a0, LONGSIZE * 4
+	addi	a1, a1, LONGSIZE * 4
+	bgeu	a2, a0, copy_loop
+
+	/* Alas! At the moment I can't load main_entry __link__ address
+	   into a0 with la. Use CONFIG_TEXT_BASE instead. This solution
+	   leads to extra cycles for repeat sp initialization. */
+
+	li	a0, CONFIG_TEXT_BASE
+	jalr	a0
diff --git a/arch/riscv/configs/erizo_generic_defconfig b/arch/riscv/configs/erizo_generic_defconfig
new file mode 100644
index 0000000000..2ea1e46cc9
--- /dev/null
+++ b/arch/riscv/configs/erizo_generic_defconfig
@@ -0,0 +1,51 @@
+# CONFIG_GLOBALVAR is not set
+CONFIG_TEXT_BASE=0x80000000
+CONFIG_MEMORY_LAYOUT_FIXED=y
+CONFIG_STACK_BASE=0x800e0000
+CONFIG_STACK_SIZE=0x20000
+CONFIG_MALLOC_BASE=0x80100000
+CONFIG_MALLOC_SIZE=0x100000
+CONFIG_MALLOC_TLSF=y
+CONFIG_PANIC_HANG=y
+CONFIG_HUSH_FANCY_PROMPT=y
+CONFIG_CMDLINE_EDITING=y
+CONFIG_AUTO_COMPLETE=y
+# CONFIG_ERRNO_MESSAGES is not set
+# CONFIG_TIMESTAMP is not set
+# CONFIG_BOOTM is not set
+# CONFIG_ENV_HANDLING is not set
+CONFIG_POLLER=y
+CONFIG_DEBUG_LL=y
+CONFIG_LONGHELP=y
+CONFIG_CMD_IOMEM=y
+CONFIG_CMD_IMD=y
+CONFIG_CMD_MEMINFO=y
+CONFIG_CMD_GO=y
+CONFIG_CMD_LOADY=y
+CONFIG_CMD_CMP=y
+CONFIG_CMD_MD5SUM=y
+CONFIG_CMD_SHA1SUM=y
+CONFIG_CMD_MSLEEP=y
+CONFIG_CMD_SLEEP=y
+CONFIG_CMD_MEMTEST=y
+CONFIG_CMD_MM=y
+CONFIG_CMD_FLASH=y
+CONFIG_CMD_GPIO=y
+CONFIG_CMD_I2C=y
+CONFIG_CMD_SPI=y
+CONFIG_CMD_OF_DUMP=y
+CONFIG_CMD_TIME=y
+CONFIG_CMD_DHRYSTONE=y
+CONFIG_OFDEVICE=y
+CONFIG_DRIVER_SERIAL_NS16550=y
+CONFIG_DRIVER_SPI_GPIO=y
+CONFIG_I2C=y
+CONFIG_I2C_GPIO=y
+CONFIG_MTD=y
+# CONFIG_MTD_OOB_DEVICE is not set
+CONFIG_MTD_M25P80=y
+CONFIG_CLOCKSOURCE_DUMMY_RATE=60000
+CONFIG_EEPROM_AT24=y
+CONFIG_GPIO_GENERIC_PLATFORM=y
+# CONFIG_PINCTRL is not set
+CONFIG_DIGEST_CRC32_GENERIC=y
diff --git a/arch/riscv/dts/.gitignore b/arch/riscv/dts/.gitignore
new file mode 100644
index 0000000000..077903c50a
--- /dev/null
+++ b/arch/riscv/dts/.gitignore
@@ -0,0 +1 @@
+*dtb*
diff --git a/arch/riscv/dts/Makefile b/arch/riscv/dts/Makefile
new file mode 100644
index 0000000000..903fe8ff34
--- /dev/null
+++ b/arch/riscv/dts/Makefile
@@ -0,0 +1,13 @@
+BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_BUILTIN_DTB_NAME))
+ifneq ($(BUILTIN_DTB),)
+obj-dtb-$(CONFIG_BUILTIN_DTB) += $(BUILTIN_DTB).dtb.o
+endif
+
+obj-dtb-$(CONFIG_BOARD_ERIZO_GENERIC) += erizo-generic.dtb.o
+
+# just to build a built-in.o. Otherwise compilation fails when no devicetree is
+# created.
+obj- += dummy.o
+
+always := $(dtb-y)
+clean-files := *.dtb *.dtb.S .*.dtc .*.pre .*.dts
diff --git a/arch/riscv/dts/erizo-generic.dts b/arch/riscv/dts/erizo-generic.dts
new file mode 100644
index 0000000000..d1f8d57168
--- /dev/null
+++ b/arch/riscv/dts/erizo-generic.dts
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "erizo.dtsi"
+#include <dt-bindings/gpio/gpio.h>
+
+/ {
+	model = "generic Erizo SoC board";
+	compatible = "miet-riscv-workgroup,erizo-generic-board";
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x80000000 0x00800000>;
+	};
+};
diff --git a/arch/riscv/dts/erizo.dtsi b/arch/riscv/dts/erizo.dtsi
new file mode 100644
index 0000000000..07534798ac
--- /dev/null
+++ b/arch/riscv/dts/erizo.dtsi
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/dts-v1/;
+
+/ {
+	compatible = "miet-riscv-workgroup,erizo";
+
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	clocks {
+		ref_clk: ref_clk {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <24000000>;
+		};
+	};
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "cliffordwolf,picorv32";
+			clocks = <&ref_clk>;
+			reg = <0>;
+		};
+	};
+
+	uart0: uart@90000000 {
+		compatible = "ns16550a";
+		reg = <0x90000000 0x20>;
+		reg-shift = <2>;
+		clocks = <&ref_clk>;
+	};
+
+	gpio0: gpio@91000000 {
+		compatible = "wd,mbl-gpio";
+		reg-names = "dat", "dirout";
+		reg = <0x91000000 0x4>,
+			<0x91000004 0x4>;
+		#gpio-cells = <2>;
+		gpio-controller;
+	};
+};
diff --git a/arch/riscv/include/asm/barebox.h b/arch/riscv/include/asm/barebox.h
new file mode 100644
index 0000000000..2997587d82
--- /dev/null
+++ b/arch/riscv/include/asm/barebox.h
@@ -0,0 +1 @@
+/* dummy */
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h
new file mode 100644
index 0000000000..b4a2f5f0b7
--- /dev/null
+++ b/arch/riscv/include/asm/bitops.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _ASM_BITOPS_H_
+#define _ASM_BITOPS_H_
+
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/ffs.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/ops.h>
+
+#define set_bit(x, y)			__set_bit(x, y)
+#define clear_bit(x, y)			__clear_bit(x, y)
+#define change_bit(x, y)		__change_bit(x, y)
+#define test_and_set_bit(x, y)		__test_and_set_bit(x, y)
+#define test_and_clear_bit(x, y)	__test_and_clear_bit(x, y)
+#define test_and_change_bit(x, y)	__test_and_change_bit(x, y)
+
+#endif /* _ASM_BITOPS_H_ */
diff --git a/arch/riscv/include/asm/bitsperlong.h b/arch/riscv/include/asm/bitsperlong.h
new file mode 100644
index 0000000000..4641e7e485
--- /dev/null
+++ b/arch/riscv/include/asm/bitsperlong.h
@@ -0,0 +1,10 @@
+#ifndef __ASM_BITSPERLONG_H
+#define __ASM_BITSPERLONG_H
+
+#ifdef __riscv64
+#define BITS_PER_LONG 64
+#else
+#define BITS_PER_LONG 32
+#endif
+
+#endif /* __ASM_BITSPERLONG_H */
diff --git a/arch/riscv/include/asm/byteorder.h b/arch/riscv/include/asm/byteorder.h
new file mode 100644
index 0000000000..0be826927b
--- /dev/null
+++ b/arch/riscv/include/asm/byteorder.h
@@ -0,0 +1,6 @@
+#ifndef _ASM_RISCV_BYTEORDER_H
+#define _ASM_RISCV_BYTEORDER_H
+
+#include <linux/byteorder/little_endian.h>
+
+#endif /* _ASM_RISCV_BYTEORDER_H */
diff --git a/arch/riscv/include/asm/common.h b/arch/riscv/include/asm/common.h
new file mode 100644
index 0000000000..bc8a17e30b
--- /dev/null
+++ b/arch/riscv/include/asm/common.h
@@ -0,0 +1,6 @@
+#ifndef ASM_RISCV_COMMON_H
+#define ASM_RISCV_COMMON_H
+
+/* nothing special yet */
+
+#endif /* ASM_RISCV_COMMON_H */
diff --git a/arch/riscv/include/asm/debug_ll_ns16550.h b/arch/riscv/include/asm/debug_ll_ns16550.h
new file mode 100644
index 0000000000..e891cbda25
--- /dev/null
+++ b/arch/riscv/include/asm/debug_ll_ns16550.h
@@ -0,0 +1,182 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2016, 2017 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+/** @file
+ *  This file contains declaration for early output support
+ */
+#ifndef __INCLUDE_RISCV_ASM_DEBUG_LL_NS16550_H__
+#define __INCLUDE_RISCV_ASM_DEBUG_LL_NS16550_H__
+
+#include <linux/kconfig.h>
+
+#ifdef CONFIG_DEBUG_LL
+
+#ifndef DEBUG_LL_UART_ADDR
+#error DEBUG_LL_UART_ADDR is undefined!
+#endif
+
+#ifndef DEBUG_LL_UART_SHIFT
+#error DEBUG_LL_UART_SHIFT is undefined!
+#endif
+
+#ifndef DEBUG_LL_UART_DIVISOR
+#error DEBUG_LL_UART_DIVISOR is undefined!
+#endif
+
+#endif /* CONFIG_DEBUG_LL */
+
+#define UART_THR	(0x0 << DEBUG_LL_UART_SHIFT)
+#define UART_RBR	(0x0 << DEBUG_LL_UART_SHIFT)
+#define UART_DLL	(0x0 << DEBUG_LL_UART_SHIFT)
+#define UART_DLM	(0x1 << DEBUG_LL_UART_SHIFT)
+#define UART_LCR	(0x3 << DEBUG_LL_UART_SHIFT)
+#define UART_LSR	(0x5 << DEBUG_LL_UART_SHIFT)
+
+#define UART_LCR_W	0x07	/* Set UART to 8,N,2 & DLAB = 0 */
+#define UART_LCR_DLAB	0x87	/* Set UART to 8,N,2 & DLAB = 1 */
+
+#define UART_LSR_DR	0x01    /* UART received data present */
+#define UART_LSR_THRE	0x20	/* Xmit holding register empty */
+
+#if defined(DEBUG_LL_UART_IOSIZE32)
+#define UART_REG_L	lw
+#define UART_REG_S	sw
+#elif defined(DEBUG_LL_UART_IOSIZE8)
+#define UART_REG_L	lbu
+#define UART_REG_S	sb
+#else
+#error "Please define DEBUG_LL_UART_IOSIZE{8,32}"
+#endif
+
+#ifndef __ASSEMBLY__
+/*
+ * C macros
+ */
+
+#include <asm/io.h>
+
+static inline void PUTC_LL(char ch)
+{
+#ifdef CONFIG_DEBUG_LL
+	while (!(__raw_readl((u8 *)DEBUG_LL_UART_ADDR + UART_LSR) & UART_LSR_THRE))
+		;
+	__raw_writel(ch, (u8 *)DEBUG_LL_UART_ADDR + UART_THR);
+#endif /* CONFIG_DEBUG_LL */
+}
+
+static inline void debug_ll_ns16550_init(void)
+{
+#ifdef CONFIG_DEBUG_LL
+	__raw_writel(UART_LCR_DLAB, (u8 *)DEBUG_LL_UART_ADDR + UART_LCR);
+	__raw_writel(DEBUG_LL_UART_DIVISOR & 0xff, (u8 *)DEBUG_LL_UART_ADDR + UART_DLL);
+	__raw_writel((DEBUG_LL_UART_DIVISOR >> 8) & 0xff, (u8 *)DEBUG_LL_UART_ADDR + UART_DLM);
+	__raw_writel(UART_LCR_W, (u8 *)DEBUG_LL_UART_ADDR + UART_LCR);
+#endif /* CONFIG_DEBUG_LL */
+}
+#else /* __ASSEMBLY__ */
+/*
+ * Macros for use in assembly language code
+ */
+
+.macro	debug_ll_ns16550_init
+#ifdef CONFIG_DEBUG_LL
+	li	t0, DEBUG_LL_UART_ADDR
+
+	li	t1, UART_LCR_DLAB		/* DLAB on */
+	UART_REG_S	t1, UART_LCR(t0)		/* Write it out */
+
+	li	t1, DEBUG_LL_UART_DIVISOR
+	UART_REG_S	t1, UART_DLL(t0)		/* write low order byte */
+	srl	t1, t1, 8
+	UART_REG_S	t1, UART_DLM(t0)		/* write high order byte */
+
+	li	t1, UART_LCR_W			/* DLAB off */
+	UART_REG_S	t1, UART_LCR(t0)		/* Write it out */
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+/*
+ * output a character in a0
+ */
+.macro	debug_ll_outc_a0
+#ifdef CONFIG_DEBUG_LL
+
+	li	t0, DEBUG_LL_UART_ADDR
+
+201:
+	UART_REG_L	t1, UART_LSR(t0)	/* get line status */
+	andi	t1, t1, UART_LSR_THRE	/* check for transmitter empty */
+	beqz	t1, 201b			/* try again */
+
+	UART_REG_S	a0, UART_THR(t0)	/* write the character */
+
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+/*
+ * output a character
+ */
+.macro	debug_ll_outc chr
+#ifdef CONFIG_DEBUG_LL
+	li	a0, \chr
+	debug_ll_outc_a0
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+/*
+ * output CR + NL
+ */
+.macro	debug_ll_ns16550_outnl
+#ifdef CONFIG_DEBUG_LL
+	debug_ll_outc '\r'
+	debug_ll_outc '\n'
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+/*
+ * check character in input buffer
+ * return value:
+ *  v0 = 0   no character in input buffer
+ *  v0 != 0  character in input buffer
+ */
+.macro	debug_ll_tstc
+#ifdef CONFIG_DEBUG_LL
+	li      t0, DEBUG_LL_UART_ADDR
+
+	/* get line status and check for data present */
+	UART_REG_L	s0, UART_LSR(t0)
+	andi	s0, s0, UART_LSR_DR
+
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+/*
+ * get character to v0
+ */
+.macro	debug_ll_getc
+#ifdef CONFIG_DEBUG_LL
+
+204:
+	debug_ll_tstc
+
+	/* try again */
+	beqz	s0, 204b
+
+	/* read a character */
+	UART_REG_L	s0, UART_RBR(t0)
+
+#endif /* CONFIG_DEBUG_LL */
+.endm
+#endif /* __ASSEMBLY__ */
+
+#endif /* __INCLUDE_RISCV_ASM_DEBUG_LL_NS16550_H__ */
diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h
new file mode 100644
index 0000000000..7134fa0582
--- /dev/null
+++ b/arch/riscv/include/asm/elf.h
@@ -0,0 +1,11 @@
+#ifndef __ASM_RISCV_ELF_H__
+#define __ASM_RISCV_ELF_H__
+
+#if __SIZEOF_POINTER__ == 8
+#define ELF_CLASS	ELFCLASS64
+#define CONFIG_PHYS_ADDR_T_64BIT
+#else
+#define ELF_CLASS	ELFCLASS32
+#endif
+
+#endif /* __ASM_RISCV_ELF_H__ */
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h
new file mode 100644
index 0000000000..3cdea7fcac
--- /dev/null
+++ b/arch/riscv/include/asm/io.h
@@ -0,0 +1,8 @@
+#ifndef __ASM_RISCV_IO_H
+#define __ASM_RISCV_IO_H
+
+#define IO_SPACE_LIMIT 0
+
+#include <asm-generic/io.h>
+
+#endif /* __ASM_RISCV_IO_H */
diff --git a/arch/riscv/include/asm/mmu.h b/arch/riscv/include/asm/mmu.h
new file mode 100644
index 0000000000..95af871420
--- /dev/null
+++ b/arch/riscv/include/asm/mmu.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_MMU_H
+#define __ASM_MMU_H
+
+#define MAP_ARCH_DEFAULT MAP_UNCACHED
+
+#endif /* __ASM_MMU_H */
diff --git a/arch/riscv/include/asm/posix_types.h b/arch/riscv/include/asm/posix_types.h
new file mode 100644
index 0000000000..22cae6230c
--- /dev/null
+++ b/arch/riscv/include/asm/posix_types.h
@@ -0,0 +1 @@
+#include <asm-generic/posix_types.h>
diff --git a/arch/riscv/include/asm/riscv_nmon.h b/arch/riscv/include/asm/riscv_nmon.h
new file mode 100644
index 0000000000..caf213cdd8
--- /dev/null
+++ b/arch/riscv/include/asm/riscv_nmon.h
@@ -0,0 +1,234 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * nano-monitor for RISC-V CPU
+ *
+ * Copyright (C) 2016, 2017 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __ASM_RISCV_NMON_H
+#define __ASM_RISCV_NMON_H
+
+#define CODE_ESC	0x1b
+
+.macro nmon_outs msg
+
+	la	a1, \msg
+
+	jal	_nmon_outs
+
+.endm
+
+/*
+ * output a 32-bit value in hex
+ */
+.macro debug_ll_outhexw
+#ifdef CONFIG_DEBUG_LL
+	move	t6, a0
+	li	t5, 32
+
+202:
+	addi	t5, t5, -4
+	srl	a0, t6, t5
+
+	/* output one hex digit */
+	andi	a0, a0, 15
+	li	t4, 10
+	blt	a0, t4, 203f
+
+	addi	a0, a0, ('a' - '9' - 1)
+
+203:
+	addi	a0, a0, '0'
+
+	debug_ll_outc_a0
+
+	li	t4, 1
+	bge	t5, t4, 202b
+
+#endif /* CONFIG_DEBUG_LL */
+.endm
+
+.macro riscv_nmon
+
+#ifdef CONFIG_NMON
+
+nmon_main_help:
+#ifdef CONFIG_NMON_HELP
+	nmon_outs	msg_nmon_help
+#endif /* CONFIG_NMON_HELP */
+
+nmon_main:
+	nmon_outs	msg_prompt
+
+	debug_ll_getc
+
+	li	a0, 'q'
+	bne	s0, a0, 3f
+
+	jal	_nmon_outc_a0
+
+	j	nmon_exit
+
+3:
+	li	a0, 'd'
+	beq	s0, a0, nmon_cmd_d
+
+	li	a0, 'w'
+	beq	s0, a0, nmon_cmd_w
+
+	li	a0, 'g'
+	beq	s0, a0, nmon_cmd_g
+
+	j	nmon_main_help
+
+nmon_cmd_d:
+	jal	_nmon_outc_a0
+
+	li	a0, ' '
+	jal	_nmon_outc_a0
+
+	jal	_nmon_gethexw
+
+	nmon_outs	msg_nl
+
+	lw	a0, (s0)
+	debug_ll_outhexw
+
+	j	nmon_main
+
+nmon_cmd_w:
+	jal	_nmon_outc_a0
+
+	li	a0, ' '
+	jal	_nmon_outc_a0
+
+	jal	_nmon_gethexw
+	move	s2, s0
+
+	li	a0, ' '
+	jal	_nmon_outc_a0
+	jal	_nmon_gethexw
+
+	sw	s0, 0(s2)
+	j	nmon_main
+
+nmon_cmd_g:
+	jal	_nmon_outc_a0
+
+	li	a0, ' '
+	jal	_nmon_outc_a0
+
+	jal	_nmon_gethexw
+	move	s2, s0
+
+	nmon_outs	msg_nl
+
+	jalr	s2
+	j	nmon_main
+
+_nmon_outc_a0:
+	debug_ll_outc_a0
+	jr	ra
+
+_nmon_outs:
+
+	lb	a0, 0(a1)
+	addi	a1, a1, 1
+	beqz	a0, _nmon_jr_ra_exit
+
+	debug_ll_outc_a0
+
+	j	_nmon_outs
+
+_nmon_gethexw:
+
+	li	t3, 8
+	li	t2, 0
+
+_get_hex_digit:
+	debug_ll_getc
+
+	li	s1, CODE_ESC
+	beq	s0, s1, nmon_main
+
+	li	s1, '0'
+	bge	s0, s1, 0f
+	j	_get_hex_digit
+
+0:
+	li	s1, '9'
+	ble	s0, s1, 9f
+
+	li	s1, 'f'
+	ble	s0, s1, 1f
+	j	_get_hex_digit
+
+1:
+	li	s1, 'a'
+	bge	s0, s1, 8f
+
+	j	_get_hex_digit
+
+8: /* s0 \in {'a', 'b' ... 'f'} */
+	sub	a3, s0, s1
+	addi	a3, a3, 0xa
+	j	0f
+
+9: /* s0 \in {'0', '1' ... '9'} */
+	li	a3, '0'
+	sub	a3, s0, a3
+
+0:	move	a0, s0
+	debug_ll_outc_a0
+
+	sll	t2, t2, 4
+	or	t2, t2, a3
+	li	t0, 1
+	sub	t3, t3, t0
+
+	beqz	t3, 0f
+
+	j	_get_hex_digit
+
+0:
+	move	s0, t2
+
+_nmon_jr_ra_exit:
+	jr	ra
+
+msg_prompt:
+	.asciz "\r\nnmon> "
+
+msg_nl:
+	.asciz "\r\n"
+
+msg_bsp:
+	.asciz "\b \b"
+
+#ifdef CONFIG_NMON_HELP
+msg_nmon_help:
+	.ascii "\r\n\r\nnmon commands:\r\n"
+	.ascii " q - quit\r\n"
+	.ascii " d <addr> - read 32-bit word from <addr>\r\n"
+	.ascii " w <addr> <val> - write 32-bit word to <addr>\r\n"
+	.ascii " g <addr> - jump to <addr>\r\n"
+	.asciz "   use <ESC> key to interrupt current command\r\n"
+#endif /* CONFIG_NMON_HELP */
+
+	.align 2
+nmon_exit:
+	nmon_outs	msg_nl
+
+#endif /* CONFIG_NMON */
+
+.endm
+
+#endif /* __ASM_RISCV_NMON_H */
diff --git a/arch/riscv/include/asm/sections.h b/arch/riscv/include/asm/sections.h
new file mode 100644
index 0000000000..2b8c516038
--- /dev/null
+++ b/arch/riscv/include/asm/sections.h
@@ -0,0 +1 @@
+#include <asm-generic/sections.h>
diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h
new file mode 100644
index 0000000000..2997587d82
--- /dev/null
+++ b/arch/riscv/include/asm/string.h
@@ -0,0 +1 @@
+/* dummy */
diff --git a/arch/riscv/include/asm/swab.h b/arch/riscv/include/asm/swab.h
new file mode 100644
index 0000000000..60a90120b6
--- /dev/null
+++ b/arch/riscv/include/asm/swab.h
@@ -0,0 +1,6 @@
+#ifndef _ASM_SWAB_H
+#define _ASM_SWAB_H
+
+/* nothing. use generic functions */
+
+#endif /* _ASM_SWAB_H */
diff --git a/arch/riscv/include/asm/types.h b/arch/riscv/include/asm/types.h
new file mode 100644
index 0000000000..ba386ab4c5
--- /dev/null
+++ b/arch/riscv/include/asm/types.h
@@ -0,0 +1,60 @@
+#ifndef __ASM_RISCV_TYPES_H
+#define __ASM_RISCV_TYPES_H
+
+#ifdef __riscv64
+/*
+ * This is used in dlmalloc. On RISCV64 we need it to be 64 bit
+ */
+#define INTERNAL_SIZE_T unsigned long
+
+/*
+ * This is a Kconfig variable in the Kernel, but we want to detect
+ * this during compile time, so we set it here.
+ */
+#define CONFIG_PHYS_ADDR_T_64BIT
+
+#endif
+
+typedef unsigned short umode_t;
+
+/*
+ * __xx is ok: it doesn't pollute the POSIX namespace. Use these in the
+ * header files exported to user space
+ */
+
+typedef __signed__ char __s8;
+typedef unsigned char __u8;
+
+typedef __signed__ short __s16;
+typedef unsigned short __u16;
+
+typedef __signed__ int __s32;
+typedef unsigned int __u32;
+
+#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
+typedef __signed__ long long __s64;
+typedef unsigned long long __u64;
+#endif
+
+/*
+ * These aren't exported outside the kernel to avoid name space clashes
+ */
+#ifdef __KERNEL__
+
+typedef signed char s8;
+typedef unsigned char u8;
+
+typedef signed short s16;
+typedef unsigned short u16;
+
+typedef signed int s32;
+typedef unsigned int u32;
+
+typedef signed long long s64;
+typedef unsigned long long u64;
+
+#include <asm/bitsperlong.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_RISCV_TYPES_H */
diff --git a/arch/riscv/include/asm/unaligned.h b/arch/riscv/include/asm/unaligned.h
new file mode 100644
index 0000000000..aaebc06411
--- /dev/null
+++ b/arch/riscv/include/asm/unaligned.h
@@ -0,0 +1,19 @@
+#ifndef _ASM_RISCV_UNALIGNED_H
+#define _ASM_RISCV_UNALIGNED_H
+
+/*
+ * FIXME: this file is copy-n-pasted from sandbox's unaligned.h
+ */
+
+#include <linux/unaligned/access_ok.h>
+#include <linux/unaligned/generic.h>
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define get_unaligned __get_unaligned_le
+#define put_unaligned __put_unaligned_le
+#else
+#define get_unaligned __get_unaligned_be
+#define put_unaligned __put_unaligned_be
+#endif
+
+#endif /* _ASM_RISCV_UNALIGNED_H */
diff --git a/arch/riscv/lib/.gitignore b/arch/riscv/lib/.gitignore
new file mode 100644
index 0000000000..d1165788c9
--- /dev/null
+++ b/arch/riscv/lib/.gitignore
@@ -0,0 +1 @@
+barebox.lds
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
new file mode 100644
index 0000000000..a1df0b7dc7
--- /dev/null
+++ b/arch/riscv/lib/Makefile
@@ -0,0 +1,3 @@
+extra-y += barebox.lds
+
+obj-y += riscv_timer.o
diff --git a/arch/riscv/lib/asm-offsets.c b/arch/riscv/lib/asm-offsets.c
new file mode 100644
index 0000000000..22f382b71e
--- /dev/null
+++ b/arch/riscv/lib/asm-offsets.c
@@ -0,0 +1,12 @@
+/*
+ * Generate definitions needed by assembly language modules.
+ * This code generates raw asm output which is post-processed to extract
+ * and format the required data.
+ */
+
+#include <linux/kbuild.h>
+
+int main(void)
+{
+	return 0;
+}
diff --git a/arch/riscv/lib/barebox.lds.S b/arch/riscv/lib/barebox.lds.S
new file mode 100644
index 0000000000..ffb97f40e8
--- /dev/null
+++ b/arch/riscv/lib/barebox.lds.S
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2016 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <asm-generic/barebox.lds.h>
+
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+SECTIONS
+{
+	. = TEXT_BASE;
+
+	. = ALIGN(8);
+	.text      :
+	{
+		_stext = .;
+		_start = .;
+		KEEP(*(.text_entry*))
+		_text = .;
+		*(.text*)
+	}
+
+	. = ALIGN(8);
+	.rodata : { *(.rodata*) }
+
+	_etext = .;			/* End of text and rodata section */
+	_sdata = .;
+
+	. = ALIGN(8);
+	.data : { *(.data*) }
+
+	.barebox_imd : { BAREBOX_IMD }
+
+	. = ALIGN(8);
+	.got : { *(.got*) }
+
+	. = .;
+	__barebox_cmd_start = .;
+	.barebox_cmd : { BAREBOX_CMDS }
+	__barebox_cmd_end = .;
+
+	__barebox_magicvar_start = .;
+	.barebox_magicvar : { BAREBOX_MAGICVARS }
+	__barebox_magicvar_end = .;
+
+	__barebox_initcalls_start = .;
+	.barebox_initcalls : { INITCALLS }
+	__barebox_initcalls_end = .;
+
+	__barebox_exitcalls_start = .;
+	.barebox_exitcalls : { EXITCALLS }
+	__barebox_exitcalls_end = .;
+
+	__usymtab_start = .;
+	__usymtab : { BAREBOX_SYMS }
+	__usymtab_end = .;
+
+	.rela.dyn : { *(.rela*) }
+
+	.oftables : { BAREBOX_CLK_TABLE() }
+
+	.dtb : { BAREBOX_DTB() }
+
+	_edata = .;
+	. = ALIGN(8);
+	__bss_start = .;
+	.bss : { *(.bss*) *(.sbss*) }
+	__bss_stop = .;
+	_end = .;
+}
diff --git a/arch/riscv/lib/riscv_timer.c b/arch/riscv/lib/riscv_timer.c
new file mode 100644
index 0000000000..919d77d4b5
--- /dev/null
+++ b/arch/riscv/lib/riscv_timer.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2017 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+/**
+ * @file
+ * @brief Clocksource based on RISC-V cycle CSR timer
+ */
+
+#include <init.h>
+#include <of.h>
+#include <linux/clk.h>
+#include <clock.h>
+
+static uint64_t rdcycle_read(void)
+{
+	register unsigned long __v;
+
+	__asm__ __volatile__ ("rdcycle %0" : "=r" (__v));
+
+	return __v;
+}
+
+static struct clocksource rdcycle_cs = {
+	.read	= rdcycle_read,
+	.mask	= CLOCKSOURCE_MASK(32),
+};
+
+static int rdcycle_cs_init(void)
+{
+	unsigned int cycle_frequency;
+
+	/* default rate: 100 MHz */
+	cycle_frequency = 100000000;
+
+	if (IS_ENABLED(CONFIG_OFTREE)) {
+		struct device_node *np;
+		struct clk *clk;
+
+		np = of_get_cpu_node(0, NULL);
+		if (np) {
+			clk = of_clk_get(np, 0);
+			if (!IS_ERR(clk)) {
+				cycle_frequency = clk_get_rate(clk);
+			}
+		}
+	}
+
+	clocks_calc_mult_shift(&rdcycle_cs.mult, &rdcycle_cs.shift,
+		cycle_frequency, NSEC_PER_SEC, 10);
+
+	return init_clock(&rdcycle_cs);
+}
+postcore_initcall(rdcycle_cs_init);
diff --git a/arch/riscv/mach-erizo/Kconfig b/arch/riscv/mach-erizo/Kconfig
new file mode 100644
index 0000000000..2400b4437b
--- /dev/null
+++ b/arch/riscv/mach-erizo/Kconfig
@@ -0,0 +1,11 @@
+if MACH_ERIZO
+
+choice
+	prompt "Board type"
+
+config BOARD_ERIZO_GENERIC
+	bool "erizo generic board"
+
+endchoice
+
+endif
diff --git a/arch/riscv/mach-erizo/Makefile b/arch/riscv/mach-erizo/Makefile
new file mode 100644
index 0000000000..d9c51e74c3
--- /dev/null
+++ b/arch/riscv/mach-erizo/Makefile
@@ -0,0 +1,3 @@
+# just to build a built-in.o. Otherwise compilation fails when no o-files is
+# created.
+obj- += dummy.o
diff --git a/arch/riscv/mach-erizo/include/mach/debug_ll.h b/arch/riscv/mach-erizo/include/mach/debug_ll.h
new file mode 100644
index 0000000000..a20acfcdfb
--- /dev/null
+++ b/arch/riscv/mach-erizo/include/mach/debug_ll.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2017 Antony Pavlov <antonynpavlov@gmail.com>
+ *
+ * This file is part of barebox.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MACH_ERIZO_DEBUG_LL__
+#define __MACH_ERIZO_DEBUG_LL__
+
+/** @file
+ *  This File contains declaration for early output support
+ */
+
+#include <linux/kconfig.h>
+
+#define DEBUG_LL_UART_ADDR	0x90000000
+#define DEBUG_LL_UART_SHIFT	2
+#define DEBUG_LL_UART_IOSIZE32
+
+#define DEBUG_LL_UART_CLK       (24000000 / 16)
+#define DEBUG_LL_UART_BPS       CONFIG_BAUDRATE
+#define DEBUG_LL_UART_DIVISOR   (DEBUG_LL_UART_CLK / DEBUG_LL_UART_BPS)
+
+#include <asm/debug_ll_ns16550.h>
+
+#endif /* __MACH_ERIZO_DEBUG_LL__ */
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index a1fac0e613..24cf4465a8 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -4,7 +4,7 @@ config OFTREE
 
 config OFTREE_MEM_GENERIC
 	depends on OFTREE
-	depends on PPC || ARM || EFI_BOOTUP || OPENRISC || SANDBOX
+	depends on PPC || ARM || EFI_BOOTUP || OPENRISC || SANDBOX || RISCV
 	def_bool y
 
 config DTC
diff --git a/scripts/erizo-nmon-image b/scripts/erizo-nmon-image
new file mode 100755
index 0000000000..b56fd365c6
--- /dev/null
+++ b/scripts/erizo-nmon-image
@@ -0,0 +1,10 @@
+#!/bin/sh
+
+if [ $# != 2 ]; then
+	echo "Usage:"
+	echo "  erizo-nmon-image <input-binary-file> <output-expect-file>"
+
+	exit 1
+fi
+
+hexdump -v -e '/4 "%08x\n"' $1 | perl -e '$a = 0x80000000; while (<>) { chop; printf("expect \"nmon> \"\n"); printf("send \"w%08x$_\"\n", $a); $a = $a + 4; }' > $2