[PATCH 8/9] RISC-V: add litex-linux board support

[Antony Pavlov]

Tested on Digilent Arty FPGA board.

Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
---
 arch/riscv/boards/Makefile               |  1 +
 arch/riscv/boards/litex-linux/Makefile   |  3 +
 arch/riscv/boards/litex-linux/lowlevel.c | 20 +++++
 arch/riscv/dts/Makefile                  |  1 +
 arch/riscv/dts/litex-linux.dts           | 96 ++++++++++++++++++++++++
 arch/riscv/mach-litex/Kconfig            |  3 +
 images/Makefile.riscv                    |  4 +
 7 files changed, 128 insertions(+)

diff --git a/arch/riscv/boards/Makefile b/arch/riscv/boards/Makefile
index 2ce9af41e0..d477cce362 100644
--- a/arch/riscv/boards/Makefile
+++ b/arch/riscv/boards/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_BOARD_ERIZO_GENERIC)	+= erizo/
+obj-$(CONFIG_BOARD_LITEX_LINUX)	+= litex-linux/
diff --git a/arch/riscv/boards/litex-linux/Makefile b/arch/riscv/boards/litex-linux/Makefile
new file mode 100644
index 0000000000..3d217ffe0b
--- /dev/null
+++ b/arch/riscv/boards/litex-linux/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+pbl-y += lowlevel.o
diff --git a/arch/riscv/boards/litex-linux/lowlevel.c b/arch/riscv/boards/litex-linux/lowlevel.c
new file mode 100644
index 0000000000..9ac1a3a42e
--- /dev/null
+++ b/arch/riscv/boards/litex-linux/lowlevel.c
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <common.h>
+#include <asm/barebox-riscv.h>
+#include <debug_ll.h>
+
+ENTRY_FUNCTION(start_litex_linux, a0, a1, a2)
+{
+	extern char __dtb_z_litex_linux_start[];
+	extern void __barebox_nmon_entry(void);
+
+	if (IS_ENABLED(CONFIG_NMON))
+		__barebox_nmon_entry();
+	putc_ll('>');
+
+	/* On POR, we are running from read-only memory here. */
+
+	barebox_riscv_entry(0x40000000, SZ_256M,
+			    __dtb_z_litex_linux_start + get_runtime_offset());
+}
diff --git a/arch/riscv/dts/Makefile b/arch/riscv/dts/Makefile
index 4041c34e0c..dc5237b5bb 100644
--- a/arch/riscv/dts/Makefile
+++ b/arch/riscv/dts/Makefile
@@ -5,5 +5,6 @@
 obj- += dummy.o
 
 pbl-$(CONFIG_BOARD_ERIZO_GENERIC) += erizo-generic.dtb.o
+pbl-$(CONFIG_BOARD_LITEX_LINUX) += litex-linux.dtb.o
 
 clean-files := *.dtb *.dtb.S .*.dtc .*.pre .*.dts
diff --git a/arch/riscv/dts/litex-linux.dts b/arch/riscv/dts/litex-linux.dts
new file mode 100644
index 0000000000..aa7e072305
--- /dev/null
+++ b/arch/riscv/dts/litex-linux.dts
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "litex_soc_linux.dtsi"
+
+#include <dt-bindings/gpio/gpio.h>
+
+/ {
+	model = "LiteX VexRiscV-SoC-Linux";
+	compatible = "litex,vexriscv-soc-linux";
+
+	aliases {
+		rom = &rom;
+		sram = &sram;
+	};
+
+	/* ARTY board */
+	rom: rom at 00000000 {
+		compatible = "mmio-sram";
+		reg = <0x00000000 0x00008000>;
+		read-only;
+	};
+
+	sram: sram at 20000000 {
+		compatible = "mmio-sram";
+		reg = <0x20000000 0x00004000>;
+	};
+
+	main_ram: memory at 40000000 {
+		device_type = "memory";
+		reg = <0x40000000 0x10000000>;
+	};
+};
+
+&uart0 {
+	status = "okay";
+};
+
+&mac0 {
+	status = "okay";
+};
+
+&spi0 {
+	status = "okay";
+
+	spiflash: w25q128 at 0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "winbond,w25q128", "jedec,spi-nor";
+		spi-max-frequency = <104000000>;
+		reg = <0>;
+	};
+};
+
+/ {
+	ledsgpio: gpio at f0005000 {
+		compatible = "ti,74175";
+		reg = <0xf0005000 0x4>;
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		ld0 {
+			label = "arty:green:ld0";
+			gpios = <&ledsgpio 0 GPIO_ACTIVE_HIGH>;
+			default-state = "off";
+		};
+
+		ld1 {
+			label = "arty:green:ld1";
+			gpios = <&ledsgpio 1 GPIO_ACTIVE_HIGH>;
+			default-state = "off";
+		};
+
+		ld2 {
+			label = "arty:green:ld2";
+			gpios = <&ledsgpio 2 GPIO_ACTIVE_HIGH>;
+			default-state = "off";
+		};
+
+		ld3 {
+			label = "arty:green:ld3";
+			gpios = <&ledsgpio 3 GPIO_ACTIVE_HIGH>;
+			default-state = "off";
+		};
+	};
+
+	swgpio: gpio at f0007000 {
+		compatible = "ti,74125";
+		reg = <0xf0007000 0x4>;
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
+};
diff --git a/arch/riscv/mach-litex/Kconfig b/arch/riscv/mach-litex/Kconfig
index 19d5927e44..3ff03b0e02 100644
--- a/arch/riscv/mach-litex/Kconfig
+++ b/arch/riscv/mach-litex/Kconfig
@@ -3,6 +3,9 @@ if MACH_LITEX
 choice
 	prompt "Board type"
 
+config BOARD_LITEX_LINUX
+	bool "litex linux board"
+
 endchoice
 
 endif
diff --git a/images/Makefile.riscv b/images/Makefile.riscv
index 463c6ce440..831858a54d 100644
--- a/images/Makefile.riscv
+++ b/images/Makefile.riscv
@@ -10,3 +10,7 @@ $(obj)/%.nmon: $(obj)/%.img FORCE
 pblb-$(CONFIG_BOARD_ERIZO_GENERIC) += start_erizo_generic
 FILE_barebox-erizo-generic.img = start_erizo_generic.pblb
 image-$(CONFIG_BOARD_ERIZO_GENERIC) += barebox-erizo-generic.img barebox-erizo-generic.nmon
+
+pblb-$(CONFIG_BOARD_LITEX_LINUX) += start_litex_linux
+FILE_barebox-litex-linux.img = start_litex_linux.pblb
+image-$(CONFIG_BOARD_LITEX_LINUX) += barebox-litex-linux.img
-- 
2.31.1