From 45964263e42b9728dd206936c157bfd1bdb6918a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Thu, 13 Aug 2020 19:49:22 +0200 Subject: target/mips/op_helper: Document Invalidate/Writeback opcodes as no-op MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit QEMU does not model caches, so there is not much to do with the Invalidate/Writeback opcodes. Make it explicit adding a comment. Suggested-by: Jiaxun Yang Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Richard Henderson Reviewed-by: Jiaxun Yang Message-Id: <20200813181527.22551-3-f4bug@amsat.org> --- target/mips/op_helper.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'target') diff --git a/target/mips/op_helper.c b/target/mips/op_helper.c index c15f5c0776..2496d1dd71 100644 --- a/target/mips/op_helper.c +++ b/target/mips/op_helper.c @@ -1586,6 +1586,11 @@ void helper_cache(CPUMIPSState *env, target_ulong addr, uint32_t op) memory_region_dispatch_read(env->itc_tag, index, &env->CP0_TagLo, MO_64, MEMTXATTRS_UNSPECIFIED); break; + case 0b000: /* Index Invalidate */ + case 0b100: /* Hit Invalidate */ + case 0b110: /* Hit Writeback */ + /* no-op */ + break; default: break; } -- cgit v1.2.3