add 3d game

I added a simple 3D maze game that is a pretty impressive demo of what Microwatt can do.

It's based on #347

Signed-off-by: Jacob Lifshay <programmerjake@gmail.com>

include/console.h

@@ -1,11 +1,24 @@
+#pragma once
+
+#include <stdbool.h>
 #include <stddef.h>
 
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 void console_init(void);
 void console_set_irq_en(bool rx_irq, bool tx_irq);
 int getchar(void);
+bool console_havechar(void);
 int putchar(int c);
 int puts(const char *str);
 
 #ifndef __USE_LIBC
 size_t strlen(const char *s);
 #endif
+
+#ifdef __cplusplus
+}
+#endif

include/liteuart_console.h

@@ -1,7 +1,18 @@
 #pragma once
 
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 int usb_getchar(void);
 bool usb_havechar(void);
 int usb_putchar(int c);
 int usb_puts(const char *str);
 void usb_console_init(void);
+
+#ifdef __cplusplus
+}
+#endif

lib/console.c

@@ -148,6 +148,13 @@ int getchar(void)
 	}
 }
 
+bool console_havechar(void) {
+	if (uart_is_std)
+		return !std_uart_rx_empty();
+	else
+		return !potato_uart_rx_empty();
+}
+
 int putchar(int c)
 {
 	if (uart_is_std) {

usb_3d_game/.gitignore

@@ -0,0 +1,6 @@
+usb_3d_game_emu
+*.o
+*.elf
+*.hex
+*.bin
+

usb_3d_game/Makefile

@@ -0,0 +1,44 @@
+ARCH = $(shell uname -m)
+ifneq ("$(ARCH)", "ppc64")
+ifneq ("$(ARCH)", "ppc64le")
+	CROSS_COMPILE ?= powerpc64le-linux-gnu-
+endif
+endif
+
+CC = $(CROSS_COMPILE)gcc
+CXX = $(CROSS_COMPILE)g++
+LD = $(CROSS_COMPILE)ld
+OBJCOPY = $(CROSS_COMPILE)objcopy
+
+COMMON_FLAGS = -Os -g -Wall -msoft-float -mno-string -mno-multiple -mno-vsx -mno-altivec -mlittle-endian -fno-stack-protector -mstrict-align -ffreestanding -fdata-sections -ffunction-sections -I../include
+COMMON_FLAGS += -Werror -Wextra
+CXXFLAGS = $(COMMON_FLAGS) -std=c++14 -fno-exceptions
+CFLAGS = $(COMMON_FLAGS) -std=c99
+ASFLAGS = $(CFLAGS)
+LDFLAGS = -T powerpc.lds
+
+all: usb_3d_game.hex
+
+console.o: ../lib/console.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
+
+liteuart_console.o: ../lib/liteuart_console.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
+
+usb_3d_game.elf: usb_3d_game.o head.o console.o liteuart_console.o
+	$(LD) $(LDFLAGS) -o $@ $^
+
+usb_3d_game.bin: usb_3d_game.elf
+	$(OBJCOPY) -O binary $^ $@
+
+usb_3d_game.hex: usb_3d_game.bin
+	../scripts/bin2hex.py $^ > $@
+
+usb_3d_game_emu: usb_3d_game.cpp
+	c++ -g -Wall -std=c++14 -Werror -Wextra -o usb_3d_game_emu usb_3d_game.cpp -DEMULATE_TARGET
+
+clean:
+	@rm -f *.o usb_3d_game.elf usb_3d_game.bin usb_3d_game.hex usb_3d_game_emu
+distclean: clean
+	rm -f *~
+

usb_3d_game/README.md

@@ -0,0 +1,39 @@
+# 3D Maze Game
+
+Based on: <https://github.com/programmerjake/rv32/tree/v0.1.0.1-alpha/software>
+
+# Run without FPGA/hardware-simulation
+
+Resize your terminal to be at least 100x76.
+
+Building:
+```bash
+cd usb_3d_game
+make usb_3d_game_emu
+```
+
+Running:
+```bash
+./usb_3d_game_emu
+```
+
+# Run on OrangeCrab v0.2.1
+
+Set the OrangeCrab into firmware upload mode by plugging it in to USB while the button is pressed, then run the following commands:
+
+Building/Flashing:
+```bash
+(cd usb_3d_game; make)
+sudo make FPGA_TARGET=ORANGE-CRAB-0.21 dfuprog DOCKER=1 LITEDRAM_GHDL_ARG=-gUSE_LITEDRAM=false RAM_INIT_FILE=usb_3d_game/usb_3d_game.hex MEMORY_SIZE=$((1<<18))
+```
+
+Then, in a separate terminal that you've resized to be at least 100x76, run (replacing ttyACM0 with whatever serial device the OrangeCrab is):
+```bash
+sudo tio /dev/ttyACM0
+```
+
+# Controls
+
+Use WASD or the Arrow keys to move around. Press Ctrl+C to quit or restart.
+
+The goal is a set of flashing blocks, nothing special yet happens when you reach them though.

usb_3d_game/head.S

@@ -0,0 +1,107 @@
+/* Copyright 2013-2014 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * 	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define STACK_TOP 0x20000
+
+#define FIXUP_ENDIAN						   \
+	tdi   0,0,0x48;	  /* Reverse endian of b . + 8		*/ \
+	b     191f;	  /* Skip trampoline if endian is good	*/ \
+	.long 0xa600607d; /* mfmsr r11				*/ \
+	.long 0x01006b69; /* xori r11,r11,1			*/ \
+	.long 0x05009f42; /* bcl 20,31,$+4			*/ \
+	.long 0xa602487d; /* mflr r10				*/ \
+	.long 0x14004a39; /* addi r10,r10,20			*/ \
+	.long 0xa64b5a7d; /* mthsrr0 r10			*/ \
+	.long 0xa64b7b7d; /* mthsrr1 r11			*/ \
+	.long 0x2402004c; /* hrfid				*/ \
+191:
+
+
+/* Load an immediate 64-bit value into a register */
+#define LOAD_IMM64(r, e)			\
+	lis     r,(e)@highest;			\
+	ori     r,r,(e)@higher;			\
+	rldicr  r,r, 32, 31;			\
+	oris    r,r, (e)@h;			\
+	ori     r,r, (e)@l;
+
+	.section ".head","ax"
+
+	/*
+	 * Microwatt currently enters in LE mode at 0x0, so we don't need to
+	 * do any endian fix ups>
+	 */
+	. = 0
+.global _start
+_start:
+	b	boot_entry
+
+	/* QEMU enters at 0x10 */
+	. = 0x10
+	FIXUP_ENDIAN
+	b	boot_entry
+
+	. = 0x100
+	FIXUP_ENDIAN
+	b	boot_entry
+
+.global boot_entry
+boot_entry:
+	/* setup stack */
+	LOAD_IMM64(%r1, STACK_TOP - 0x100)
+	LOAD_IMM64(%r12, main)
+	mtctr	%r12,
+	bctrl
+	b .
+
+#define EXCEPTION(nr)		\
+	.= nr			;\
+	b	.
+
+	/* More exception stubs */
+	EXCEPTION(0x300)
+	EXCEPTION(0x380)
+	EXCEPTION(0x400)
+	EXCEPTION(0x480)
+	EXCEPTION(0x500)
+	EXCEPTION(0x600)
+	EXCEPTION(0x700)
+	EXCEPTION(0x800)
+	EXCEPTION(0x900)
+	EXCEPTION(0x980)
+	EXCEPTION(0xa00)
+	EXCEPTION(0xb00)
+	EXCEPTION(0xc00)
+	EXCEPTION(0xd00)
+	EXCEPTION(0xe00)
+	EXCEPTION(0xe20)
+	EXCEPTION(0xe40)
+	EXCEPTION(0xe60)
+	EXCEPTION(0xe80)
+	EXCEPTION(0xf00)
+	EXCEPTION(0xf20)
+	EXCEPTION(0xf40)
+	EXCEPTION(0xf60)
+	EXCEPTION(0xf80)
+#if 0
+	EXCEPTION(0x1000)
+	EXCEPTION(0x1100)
+	EXCEPTION(0x1200)
+	EXCEPTION(0x1300)
+	EXCEPTION(0x1400)
+	EXCEPTION(0x1500)
+	EXCEPTION(0x1600)
+#endif

usb_3d_game/powerpc.lds

@@ -0,0 +1,13 @@
+SECTIONS
+{
+	. = 0;
+	.head : {
+		KEEP(*(.head))
+ 	}
+	. = 0x1000;
+	.text : { *(.text) }
+	. = 0x2a000;
+	.data : { *(.data) }
+	.rodata : { *(.rodata) }
+	.bss : { *(.bss) }
+}