@@ -242,30 +242,14 @@ _scratch_init:
beq t1, a1, _fdt_reloc_done
/* t0 = source FDT start address */
add t0, a1, zero
- /* t2 = source FDT size in big-endian */
-#if __riscv_xlen > 32
- lwu t2, 4(t0)
-#else
- lw t2, 4(t0)
-#endif
- /* t3 = bit[15:8] of FDT size */
- add t3, t2, zero
- srli t3, t3, 16
- and t3, t3, a4
+ /* t2 = source FDT size (convert from big-endian) */
+ lbu t2, 7(t0)
+ lbu t3, 6(t0)
+ lbu t4, 5(t0)
+ lbu t5, 4(t0)
slli t3, t3, 8
- /* t4 = bit[23:16] of FDT size */
- add t4, t2, zero
- srli t4, t4, 8
- and t4, t4, a4
slli t4, t4, 16
- /* t5 = bit[31:24] of FDT size */
- add t5, t2, zero
- and t5, t5, a4
slli t5, t5, 24
- /* t2 = bit[7:0] of FDT size */
- srli t2, t2, 24
- and t2, t2, a4
- /* t2 = FDT size in little-endian */
or t2, t2, t3
or t2, t2, t4
or t2, t2, t5
Reduce the code size by using single-byte loads instead of bit manipulation. This method also does the right thing on (hypothetical) big-endian systems. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> --- firmware/fw_base.S | 26 +++++--------------------- 1 file changed, 5 insertions(+), 21 deletions(-)