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lib: sbi_illegal_insn: Fix FENCE.TSO emulation infinite trap loop

In case of missing "FENCE.TSO" instruction implementation,
opensbi can emulate the "FENCE.TSO" with "FENCE RW,RW", but
mepc was not incremented to continue from the next instruction
causing infinite trap.

Fixes: cb8271c8 ("lib: sbi_illegal_insn: Add emulation for fence.tso")
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Rahul Pathak 1 year ago
parent
commit
111afc1230
1 changed files with 1 additions and 0 deletions
  1. 1 0
      lib/sbi/sbi_illegal_insn.c

+ 1 - 0
lib/sbi/sbi_illegal_insn.c

@@ -40,6 +40,7 @@ static int misc_mem_opcode_insn(ulong insn, struct sbi_trap_regs *regs)
 	/* Errata workaround: emulate `fence.tso` as `fence rw, rw`. */
 	if ((insn & INSN_MASK_FENCE_TSO) == INSN_MATCH_FENCE_TSO) {
 		smp_mb();
+		regs->mepc += 4;
 		return 0;
 	}