apps for FPGA

src/main/resources/applications_for_fpga/headers/crt.S

@@ -0,0 +1,162 @@
+# See LICENSE for license details.
+
+#include "encoding.h"
+
+#if __riscv_xlen == 64
+# define LREG ld
+# define SREG sd
+# define REGBYTES 8
+#else
+# define LREG lw
+# define SREG sw
+# define REGBYTES 4
+#endif
+
+  .section ".text.init"
+  .globl _start
+_start:
+  li  x1, 0
+  li  x2, 0
+  li  x3, 0
+  li  x4, 0
+  li  x5, 0
+  li  x6, 0
+  li  x7, 0
+  li  x8, 0
+  li  x9, 0
+  li  x10,0
+  li  x11,0
+  li  x12,0
+  li  x13,0
+  li  x14,0
+  li  x15,0
+  li  x16,0
+  li  x17,0
+  li  x18,0
+  li  x19,0
+  li  x20,0
+  li  x21,0
+  li  x22,0
+  li  x23,0
+  li  x24,0
+  li  x25,0
+  li  x26,0
+  li  x27,0
+  li  x28,0
+  li  x29,0
+  li  x30,0
+  li  x31,0
+
+  # initialize trap vector
+  la t0, trap_entry
+  csrw mtvec, t0
+
+  # initialize global pointer
+.option push
+.option norelax
+  la gp, __global_pointer$
+.option pop
+
+  la  tp, _end + 63
+  and tp, tp, -64
+
+  # get core id
+  csrr a0, mhartid
+  # for now, assume only 1 core
+  li a1, 1
+1:bgeu a0, a1, 1b
+
+  # initialise stack pointer
+  li sp, 0x00005FF0
+
+  j _init
+
+  .align 2
+trap_entry:
+  addi sp, sp, -272
+
+  SREG x1, 1*REGBYTES(sp)
+  SREG x2, 2*REGBYTES(sp)
+  SREG x3, 3*REGBYTES(sp)
+  SREG x4, 4*REGBYTES(sp)
+  SREG x5, 5*REGBYTES(sp)
+  SREG x6, 6*REGBYTES(sp)
+  SREG x7, 7*REGBYTES(sp)
+  SREG x8, 8*REGBYTES(sp)
+  SREG x9, 9*REGBYTES(sp)
+  SREG x10, 10*REGBYTES(sp)
+  SREG x11, 11*REGBYTES(sp)
+  SREG x12, 12*REGBYTES(sp)
+  SREG x13, 13*REGBYTES(sp)
+  SREG x14, 14*REGBYTES(sp)
+  SREG x15, 15*REGBYTES(sp)
+  SREG x16, 16*REGBYTES(sp)
+  SREG x17, 17*REGBYTES(sp)
+  SREG x18, 18*REGBYTES(sp)
+  SREG x19, 19*REGBYTES(sp)
+  SREG x20, 20*REGBYTES(sp)
+  SREG x21, 21*REGBYTES(sp)
+  SREG x22, 22*REGBYTES(sp)
+  SREG x23, 23*REGBYTES(sp)
+  SREG x24, 24*REGBYTES(sp)
+  SREG x25, 25*REGBYTES(sp)
+  SREG x26, 26*REGBYTES(sp)
+  SREG x27, 27*REGBYTES(sp)
+  SREG x28, 28*REGBYTES(sp)
+  SREG x29, 29*REGBYTES(sp)
+  SREG x30, 30*REGBYTES(sp)
+  SREG x31, 31*REGBYTES(sp)
+
+  csrr a0, mcause
+  csrr a1, mepc
+  mv a2, sp
+  jal handle_trap
+  csrw mepc, a0
+
+  # Remain in M-mode after eret
+  # we can write to mstatus but core supports only M-mode and ignore this
+  li t0, MSTATUS_MPP
+  csrs mstatus, t0
+
+  LREG x1, 1*REGBYTES(sp)
+  LREG x2, 2*REGBYTES(sp)
+  LREG x3, 3*REGBYTES(sp)
+  LREG x4, 4*REGBYTES(sp)
+  LREG x5, 5*REGBYTES(sp)
+  LREG x6, 6*REGBYTES(sp)
+  LREG x7, 7*REGBYTES(sp)
+  LREG x8, 8*REGBYTES(sp)
+  LREG x9, 9*REGBYTES(sp)
+  LREG x10, 10*REGBYTES(sp)
+  LREG x11, 11*REGBYTES(sp)
+  LREG x12, 12*REGBYTES(sp)
+  LREG x13, 13*REGBYTES(sp)
+  LREG x14, 14*REGBYTES(sp)
+  LREG x15, 15*REGBYTES(sp)
+  LREG x16, 16*REGBYTES(sp)
+  LREG x17, 17*REGBYTES(sp)
+  LREG x18, 18*REGBYTES(sp)
+  LREG x19, 19*REGBYTES(sp)
+  LREG x20, 20*REGBYTES(sp)
+  LREG x21, 21*REGBYTES(sp)
+  LREG x22, 22*REGBYTES(sp)
+  LREG x23, 23*REGBYTES(sp)
+  LREG x24, 24*REGBYTES(sp)
+  LREG x25, 25*REGBYTES(sp)
+  LREG x26, 26*REGBYTES(sp)
+  LREG x27, 27*REGBYTES(sp)
+  LREG x28, 28*REGBYTES(sp)
+  LREG x29, 29*REGBYTES(sp)
+  LREG x30, 30*REGBYTES(sp)
+  LREG x31, 31*REGBYTES(sp)
+
+  addi sp, sp, 272
+  mret
+
+.section ".tohost","aw",@progbits
+.align 6
+.globl tohost
+tohost: .dword 0
+.align 6
+.globl fromhost
+fromhost: .dword 0