NJU-ProjectN/abstract-machine ics2023 initialized

NJU-ProjectN/abstract-machine 3348db971fd860be5cb28e21c18f9d0e65d0c96a Merge pull request #8 from Jasonyanyusong/master

abstract-machine/am/src/mips/mips32.h

@@ -0,0 +1,24 @@
+#ifndef MIPS32_H__
+#define MIPS32_H__
+
+#include <stdint.h>
+
+static inline uint8_t  inb(uintptr_t addr) { return *(volatile uint8_t  *)addr; }
+static inline uint16_t inw(uintptr_t addr) { return *(volatile uint16_t *)addr; }
+static inline uint32_t inl(uintptr_t addr) { return *(volatile uint32_t *)addr; }
+
+static inline void outb(uintptr_t addr, uint8_t  data) { *(volatile uint8_t  *)addr = data; }
+static inline void outw(uintptr_t addr, uint16_t data) { *(volatile uint16_t *)addr = data; }
+static inline void outl(uintptr_t addr, uint32_t data) { *(volatile uint32_t *)addr = data; }
+
+#define PTE_V 0x2
+#define PTE_D 0x4
+
+// Page directory and page table constants
+#define PTXSHFT   12      // Offset of PTX in a linear address
+#define PDXSHFT   22      // Offset of PDX in a linear address
+
+#define PDX(va)     (((uint32_t)(va) >> PDXSHFT) & 0x3ff)
+#define PTX(va)     (((uint32_t)(va) >> PTXSHFT) & 0x3ff)
+
+#endif

abstract-machine/am/src/mips/nemu/cte.c

@@ -0,0 +1,54 @@
+#include <am.h>
+#include <mips/mips32.h>
+#include <klib.h>
+
+static Context* (*user_handler)(Event, Context*) = NULL;
+
+Context* __am_irq_handle(Context *c) {
+  if (user_handler) {
+    Event ev = {0};
+    uint32_t ex_code = 0;
+    switch (ex_code) {
+      default: ev.event = EVENT_ERROR; break;
+    }
+
+    c = user_handler(ev, c);
+    assert(c != NULL);
+  }
+
+  return c;
+}
+
+extern void __am_asm_trap(void);
+
+#define EX_ENTRY 0x80000180
+
+bool cte_init(Context*(*handler)(Event, Context*)) {
+  // initialize exception entry
+  const uint32_t j_opcode = 0x08000000;
+  uint32_t instr = j_opcode | (((uint32_t)__am_asm_trap >> 2) & 0x3ffffff);
+  *(uint32_t *)EX_ENTRY = instr;
+  *(uint32_t *)(EX_ENTRY + 4) = 0;  // delay slot
+  *(uint32_t *)0x80000000 = instr;  // TLB refill exception
+  *(uint32_t *)(0x80000000 + 4) = 0;  // delay slot
+
+  // register event handler
+  user_handler = handler;
+
+  return true;
+}
+
+Context *kcontext(Area kstack, void (*entry)(void *), void *arg) {
+  return NULL;
+}
+
+void yield() {
+  asm volatile("syscall 1");
+}
+
+bool ienabled() {
+  return false;
+}
+
+void iset(bool enable) {
+}

abstract-machine/am/src/mips/nemu/start.S

@@ -0,0 +1,10 @@
+.section entry, "ax"
+.globl _start
+.type _start, @function
+
+_start:
+  move $fp, $zero
+  la $sp, _stack_pointer
+  jal _trm_init
+
+.fill 0x200

abstract-machine/am/src/mips/nemu/trap.S

@@ -0,0 +1,71 @@
+
+#define MAP(c, f) c(f)
+
+#define REGS(f) \
+      f( 1) f( 2) f( 3) f( 4) f( 5) f( 6) f( 7) f( 8) f( 9) \
+f(10) f(11) f(12) f(13) f(14) f(15) f(16) f(17) f(18) f(19) \
+f(20) f(21) f(22) f(23) f(24) f(25)             f(28)       \
+f(30) f(31)
+
+#define PUSH(n) sw $n, (n * 4)($sp);
+#define POP(n)  lw $n, (n * 4)($sp);
+
+#define CONTEXT_SIZE ((31 + 6) * 4)
+#define OFFSET_SP     (29 * 4)
+#define OFFSET_LO     (32 * 4)
+#define OFFSET_HI     (33 * 4)
+#define OFFSET_CAUSE  (34 * 4)
+#define OFFSET_STATUS (35 * 4)
+#define OFFSET_EPC    (36 * 4)
+
+#define CP0_STATUS 12
+#define CP0_CAUSE  13
+#define CP0_EPC    14
+
+
+.set noat
+.globl __am_asm_trap
+__am_asm_trap:
+  move $k1, $sp
+  addiu $sp, $sp, -CONTEXT_SIZE
+
+  MAP(REGS, PUSH)
+
+  sw $k1, OFFSET_SP($sp)
+
+  mflo $t0
+  mfhi $t1
+  mfc0 $t2, $CP0_CAUSE
+  mfc0 $t3, $CP0_STATUS
+  mfc0 $t4, $CP0_EPC
+  sw $t0, OFFSET_LO($sp)
+  sw $t1, OFFSET_HI($sp)
+  sw $t2, OFFSET_CAUSE($sp)
+  sw $t3, OFFSET_STATUS($sp)
+  sw $t4, OFFSET_EPC($sp)
+
+  # allow nested exception
+  li $a0, ~0x3
+  and $t3, $t3, $a0  # clear status.exl and status.ie
+  mtc0 $t3, $CP0_STATUS
+
+  move $a0, $sp
+  jal __am_irq_handle
+
+  lw $t0, OFFSET_LO($sp)
+  lw $t1, OFFSET_HI($sp)
+  lw $t3, OFFSET_STATUS($sp)
+  lw $t4, OFFSET_EPC($sp)
+
+  # set status.exl
+  ori $t3, $t3, 0x2
+
+  mtlo $t0
+  mthi $t1
+  mtc0 $t3, $CP0_STATUS
+  mtc0 $t4, $CP0_EPC
+
+  MAP(REGS, POP)
+
+  addiu $sp, $sp, CONTEXT_SIZE
+  eret

abstract-machine/am/src/mips/nemu/vme.c

@@ -0,0 +1,42 @@
+#include <am.h>
+#include <nemu.h>
+
+#define USER_SPACE RANGE(0x40000000, 0x80000000)
+
+static void* (*pgalloc_usr)(int) = NULL;
+static void (*pgfree_usr)(void*) = NULL;
+static int vme_enable = 0;
+static PTE *cur_pdir = NULL;
+
+bool vme_init(void* (*pgalloc_f)(int), void (*pgfree_f)(void*)) {
+  pgalloc_usr = pgalloc_f;
+  pgfree_usr = pgfree_f;
+  vme_enable = 1;
+  return true;
+}
+
+void protect(AddrSpace *as) {
+  as->ptr = (PTE*)(pgalloc_usr(PGSIZE));
+  as->pgsize = PGSIZE;
+  as->area = USER_SPACE;
+}
+
+void unprotect(AddrSpace *as) {
+}
+
+void __am_get_cur_as(Context *c) {
+  c->pdir = (vme_enable ? cur_pdir : NULL);
+}
+
+void __am_switch(Context *c) {
+  if (vme_enable && c->pdir != NULL) {
+    cur_pdir = c->pdir;
+  }
+}
+
+void map(AddrSpace *as, void *va, void *pa, int prot) {
+}
+
+Context *ucontext(AddrSpace *as, Area kstack, void *entry) {
+  return NULL;
+}