Add support for clock syscalls

arch/aarch64.c

@@ -294,4 +294,82 @@ ssize_t recvfrom(int sockfd, const void* buf, size_t size, int flags, const void
   return rtn;
 }
 
+
+int clock_settime(clockid_t clockid, const struct timespec *tp) {
+  long int rtn;
+  asm volatile (
+    // Assembly Instructions
+    "mov x8, #112\n"  // Syscall number for 'listen' is 201 in AArch64
+    "mov x0, %1\n"    // fd
+    "mov x1, %2\n"    // backlog
+    "svc #0\n"        // Make the syscall
+    "mov %0, x0\n"    // save return value
+    // Output operands
+    : "=r" (rtn)
+    // Input operand
+    : "r" ((int64_t)clockid), "r"(tp)
+    // Clobbered registers
+    : "x0", "x1", "x8"
+  );
+  return (int32_t)rtn;
+}
+
+int clock_gettime(clockid_t clockid, struct timespec *tp) {
+  long int rtn;
+  asm volatile (
+    // Assembly Instructions
+    "mov x8, #113\n"  // Syscall number for 'listen' is 201 in AArch64
+    "mov x0, %1\n"    // fd
+    "mov x1, %2\n"    // backlog
+    "svc #0\n"        // Make the syscall
+    "mov %0, x0\n"    // save return value
+    // Output operands
+    : "=r" (rtn)
+    // Input operand
+    : "r" ((int64_t)clockid), "r"(tp)
+    // Clobbered registers
+    : "x0", "x1", "x8", "memory"
+  );
+  return (int32_t)rtn;
+}
+
+int clock_getres(clockid_t clockid, struct timespec *res) {
+  long int rtn;
+  asm volatile (
+    // Assembly Instructions
+    "mov x8, #114\n"  // Syscall number for 'listen' is 201 in AArch64
+    "mov x0, %1\n"    // fd
+    "mov x1, %2\n"    // backlog
+    "svc #0\n"        // Make the syscall
+    "mov %0, x0\n"    // save return value
+    // Output operands
+    : "=r" (rtn)
+    // Input operand
+    : "r" ((int64_t)clockid), "r"(res)
+    // Clobbered registers
+    : "x0", "x1", "x8", "memory"
+  );
+  return (int32_t)rtn;
+}
+
+int clock_nanosleep(clockid_t clockid, int flags, const struct timespec *t, struct timespec* remain) {
+  long int rtn;
+  asm volatile (
+    // Assembly Instructions
+    "mov x8, #115\n"  // Syscall number for 'listen' is 201 in AArch64
+    "mov x0, %1\n"    // fd
+    "mov x1, %2\n"    // backlog
+    "mov x2, %3\n"    // backlog
+    "svc #0\n"        // Make the syscall
+    "mov %0, x0\n"    // save return value
+    // Output operands
+    : "=r" (rtn)
+    // Input operand
+    : "r" ((int64_t)clockid), "r"((int64_t)flags), "r"(t), "r"(remain)
+    // Clobbered registers
+    : "x0", "x1", "x8", "memory"
+  );
+  return (int32_t)rtn;
+}
+
 #endif