add riscv32-nemu

Makefile.compile

@@ -7,6 +7,10 @@ ifeq ($(ISA), mips32)
 CROSS_COMPILE = mips-linux-gnu-
 endif
 
+ifeq ($(ISA), riscv32)
+CROSS_COMPILE = riscv-none-embed-
+endif
+
 ifeq ($(PLATFORM), navy)
 NAVY_LIBS = libndl libos libc
 INC_DIR += $(addsuffix /include/, $(addprefix $(NAVY_HOME)/libs/, $(NAVY_LIBS)))
@@ -45,6 +49,11 @@ CFLAGS_COMMON += -m32 -fno-pic -fno-omit-frame-pointer -march=i386 -mstringop-st
 ASFLAGS  += -m32
 endif
 
+ifeq ($(ISA), riscv32)
+CFLAGS_COMMON += -fno-pic -static -march=rv32im -mabi=ilp32
+ASFLAGS  += -march=rv32im -mabi=ilp32 -O0 -fno-pic
+endif
+
 ifeq ($(ISA), am_native)
 CFLAGS_COMMON += -fno-omit-frame-pointer -fno-reorder-functions
 endif

am/arch/riscv32-nemu/README.md

@@ -0,0 +1 @@
+# RISCV32-NEMU

am/arch/riscv32-nemu/img/boot/Makefile

@@ -0,0 +1,4 @@
+start.o: start.S
+	riscv-none-embed-gcc -I$(AM_HOME)/am/arch/riscv32-nemu/include -march=rv32im -mabi=ilp32 -fno-pic -MMD -c start.S -o start.o
+
+-include start.d

am/arch/riscv32-nemu/img/boot/start.S

@@ -0,0 +1,7 @@
+.globl _start
+.type _start, function
+
+_start:
+  mv s0, zero
+  la sp, _stack_pointer
+  jal _trm_init

am/arch/riscv32-nemu/img/build

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+DIR=${AM_HOME}/am/arch/riscv32-nemu/img
+DEST=$1
+shift
+CROSS_COMPILE=riscv-none-embed-
+
+make -C $DIR/boot -s
+
+${CROSS_COMPILE}ld --gc-sections -melf32lriscv -T $DIR/loader.ld -e _start -o $DEST $DIR/boot/start.o --start-group $@ --end-group
+${CROSS_COMPILE}objdump -d $DEST > $DEST.txt
+
+${CROSS_COMPILE}objcopy -S --set-section-flags .bss=alloc,contents -O binary $DEST $DEST.bin

am/arch/riscv32-nemu/img/loader.ld

@@ -0,0 +1,29 @@
+SECTIONS {
+  . = 0x80100000;
+  .text : {
+    *(.text)
+  }
+  etext = .;
+  _etext = .;
+  .rodata : {
+    *(.rodata*)
+  }
+  .data : {
+    *(.data)
+  }
+  edata = .;
+  _data = .;
+  .bss : {
+	_bss_start = .;
+    *(.bss*)
+    *(.sbss*)
+    *(.scommon)
+  }
+  _stack_top = ALIGN(4096);
+  . = _stack_top + 0x8000;
+  _stack_pointer = .;
+  end = .;
+  _end = .;
+  _heap_start = ALIGN(4096);
+  _heap_end = 0x88000000;
+}

am/arch/riscv32-nemu/img/run

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+make -C $NEMU_HOME ISA=riscv32 run ARGS="-b -l `dirname $1`/nemu-log.txt $1.bin"

am/arch/riscv32-nemu/include/arch.h

@@ -0,0 +1,27 @@
+#ifndef __ARCH_H__
+#define __ARCH_H__
+
+#include <am.h>
+
+#define PMEM_SIZE (128 * 1024 * 1024)
+#define PGSIZE    4096
+
+struct _Context {
+  struct _Protect *prot;
+  uint32_t gpr[31];
+};
+
+#define GPR1 //gpr[3]
+#define GPR2 //gpr[4]
+#define GPR3 //gpr[5]
+#define GPR4 //gpr[6]
+#define GPRx //gpr[1]
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif

am/arch/riscv32-nemu/include/riscv32.h

@@ -0,0 +1,44 @@
+#ifndef __RISCV32_H__
+#define __RISCV32_H__
+
+#ifndef __ASSEMBLER__
+
+#include <arch.h>
+
+#define MMIO_OFFSET(addr) (addr)
+
+static inline uint8_t  inb(uintptr_t addr) { return *(volatile uint8_t  *)MMIO_OFFSET(addr); }
+static inline uint16_t inw(uintptr_t addr) { return *(volatile uint16_t *)MMIO_OFFSET(addr); }
+static inline uint32_t inl(uintptr_t addr) { return *(volatile uint32_t *)MMIO_OFFSET(addr); }
+
+static inline void outb(uintptr_t addr, uint8_t  data) { *(volatile uint8_t  *)MMIO_OFFSET(addr) = data; }
+static inline void outw(uintptr_t addr, uint16_t data) { *(volatile uint16_t *)MMIO_OFFSET(addr) = data; }
+static inline void outl(uintptr_t addr, uint32_t data) { *(volatile uint32_t *)MMIO_OFFSET(addr) = data; }
+
+#define PTE_V 0x2
+#define PTE_D 0x4
+
+// Page directory and page table constants
+#define NR_PDE    1024    // # directory entries per page directory
+#define NR_PTE    1024    // # PTEs per page table
+#define PGSHFT    12      // log2(PGSIZE)
+#define PTXSHFT   12      // Offset of PTX in a linear address
+#define PDXSHFT   22      // Offset of PDX in a linear address
+
+// +--------10------+-------10-------+---------12----------+
+// | Page Directory |   Page Table   | Offset within Page  |
+// |      Index     |      Index     |                     |
+// +----------------+----------------+---------------------+
+//  \--- PDX(va) --/ \--- PTX(va) --/\------ OFF(va) ------/
+typedef uint32_t PTE;
+typedef uint32_t PDE;
+#define PDX(va)     (((uint32_t)(va) >> PDXSHFT) & 0x3ff)
+#define PTX(va)     (((uint32_t)(va) >> PTXSHFT) & 0x3ff)
+#define OFF(va)     ((uint32_t)(va) & 0xfff)
+
+// Address in page table or page directory entry
+#define PTE_ADDR(pte)   ((uint32_t)(pte) & ~0xfff)
+
+#endif
+
+#endif

am/arch/riscv32-nemu/src/devices/input.c

@@ -0,0 +1,19 @@
+#include <am.h>
+#include <riscv32.h>
+#include <amdev.h>
+
+#define KBD_DATA_MMIO 0x4060
+#define KEYDOWN_MASK 0x8000
+
+size_t input_read(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_INPUT_KBD: {
+      _KbdReg *kbd = (_KbdReg *)buf;
+      int k = inl(KBD_DATA_MMIO);
+      kbd->keydown = (k & KEYDOWN_MASK ? 1 : 0);
+      kbd->keycode = k & ~KEYDOWN_MASK;
+      return sizeof(_KbdReg);
+    }
+  }
+  return 0;
+}

am/arch/riscv32-nemu/src/devices/timer.c

@@ -0,0 +1,32 @@
+#include <am.h>
+#include <riscv32.h>
+#include <amdev.h>
+
+#define RTC_MMIO 0x4048   // Note that this is not standard
+static unsigned long boot_time;
+
+size_t timer_read(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_TIMER_UPTIME: {
+      _UptimeReg *uptime = (_UptimeReg *)buf;
+      uptime->hi = 0;
+      uptime->lo = inl(RTC_MMIO) - boot_time;
+      return sizeof(_UptimeReg);
+    }
+    case _DEVREG_TIMER_DATE: {
+      _RTCReg *rtc = (_RTCReg *)buf;
+      rtc->second = 0;
+      rtc->minute = 0;
+      rtc->hour   = 0;
+      rtc->day    = 0;
+      rtc->month  = 0;
+      rtc->year   = 2018;
+      return sizeof(_RTCReg);
+    }
+  }
+  return 0;
+}
+
+void timer_init() {
+  boot_time = inl(RTC_MMIO);
+}

am/arch/riscv32-nemu/src/devices/video.c

@@ -0,0 +1,52 @@
+#include <am.h>
+#include <riscv32.h>
+#include <amdev.h>
+#include <klib.h>
+
+#define SCREEN_MMIO 0x4100
+static int W, H;
+static uint32_t* const fb = (uint32_t *)MMIO_OFFSET(0x40000);
+
+size_t video_read(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_VIDEO_INFO: {
+      _VideoInfoReg *info = (_VideoInfoReg *)buf;
+      info->width = W;
+      info->height = H;
+      return sizeof(_VideoInfoReg);
+    }
+  }
+  return 0;
+}
+
+size_t video_write(uintptr_t reg, void *buf, size_t size) {
+  switch (reg) {
+    case _DEVREG_VIDEO_FBCTL: {
+      _FBCtlReg *ctl = (_FBCtlReg *)buf;
+      int x = ctl->x, y = ctl->y, w = ctl->w, h = ctl->h;
+      uint32_t *pixels = ctl->pixels;
+      int len = sizeof(uint32_t) * ( (x + w >= W) ? W - x : w );
+      uint32_t *p_fb = &fb[y * W + x];
+      int j;
+
+      for (j = 0; j < h; j ++) {
+        if (y + j < H) { memcpy(p_fb, pixels, len); }
+        else { break; }
+        p_fb += W;
+        pixels += w;
+      }
+
+      if (ctl->sync) {
+        // do nothing, hardware syncs.
+      }
+      return size;
+    }
+  }
+  return 0;
+}
+
+void vga_init() {
+  uint32_t data = inl(SCREEN_MMIO);
+  W = data >> 16;
+  H = data & 0xffff;
+}

am/arch/riscv32-nemu/src/ioe.c

@@ -0,0 +1,41 @@
+#include <am.h>
+#include <amdev.h>
+#include <klib.h>
+
+static inline size_t no_read(uintptr_t reg, void *buf, size_t size) {
+  assert(0);
+  return 0;
+}
+
+static inline size_t no_write(uintptr_t reg, void *buf, size_t size) {
+  assert(0);
+  return 0;
+}
+
+void vga_init();
+void timer_init();
+
+int _ioe_init() {
+  vga_init();
+  timer_init();
+  return 0;
+}
+
+size_t timer_read(uintptr_t reg, void *buf, size_t size);
+size_t video_read(uintptr_t reg, void *buf, size_t size);
+size_t video_write(uintptr_t reg, void *buf, size_t size);
+size_t input_read(uintptr_t reg, void *buf, size_t size);
+
+
+static _Device nemu_dev[] = {
+  {_DEV_TIMER,   "NEMU Timer", timer_read, no_write},
+  {_DEV_INPUT,   "NEMU Keyboard Controller", input_read, no_write},
+  {_DEV_VIDEO,   "NEMU VGA Controller", video_read, video_write},
+};
+
+#define NR_DEV (sizeof(nemu_dev) / sizeof(nemu_dev[0]))
+
+_Device *_device(int n) {
+  n --;
+  return (n >= 0 && (unsigned int)n < NR_DEV) ? &nemu_dev[n] : NULL;
+}

am/arch/riscv32-nemu/src/trm.c

@@ -0,0 +1,34 @@
+#include <am.h>
+#include <riscv32.h>
+
+// Define this macro after serial has been implemented
+#define HAS_SERIAL
+
+#define SERIAL_PORT 0x43f8
+
+extern char _heap_start;
+extern char _heap_end;
+extern int main();
+
+_Area _heap = {
+  .start = &_heap_start,
+  .end = &_heap_end,
+};
+
+void _putc(char ch) {
+#ifdef HAS_SERIAL
+  outb(SERIAL_PORT, ch);
+#endif
+}
+
+void _halt(int code) {
+  __asm__ volatile("mv a0, %0; .word 0x0000006b" : :"r"(code));
+
+  // should not reach here
+  while (1);
+}
+
+void _trm_init() {
+  int ret = main();
+  _halt(ret);
+}