dummy_rocc/dummy_rocc_test.c

   1 // The following is a RISC-V program to test the functionality of the
   2 // dummy RoCC accelerator.
   3 // Compile with riscv64-unknown-elf-gcc dummy_rocc_test.c
   4 // Run with spike --extension=dummy_rocc pk a.out
   5
   6 #include <assert.h>
   7 #include <stdio.h>
   8 #include <stdint.h>
   9
  10 int main() {
  11   uint64_t x = 123, y = 456, z = 0;
  12   // load x into accumulator 2 (funct=0)
  13   asm volatile ("custom0 x0, %0, 2, 0" : : "r"(x));
  14   // read it back into z (funct=1) to verify it
  15   asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
  16   assert(z == x);
  17   // accumulate 456 into it (funct=3)
  18   asm volatile ("custom0 x0, %0, 2, 3" : : "r"(y));
  19   // verify it
  20   asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
  21   assert(z == x+y);
  22   // do it all again, but initialize acc2 via memory this time (funct=2)
  23   asm volatile ("custom0 x0, %0, 2, 2" : : "r"(&x));
  24   asm volatile ("custom0 x0, %0, 2, 3" : : "r"(y));
  25   asm volatile ("custom0 %0, x0, 2, 1" : "=r"(z));
  26   assert(z == x+y);
  27
  28   printf("success!\n");
  29 }