target/mips: Move helper_cache() to tcg/sysemu/special_helper.c

Move helper_cache() to tcg/sysemu/special_helper.c.

The CACHE opcode is privileged and is not accessible in user
emulation. However we get a link failure when restricting the
symbol to sysemu. For now, add a stub helper to satisfy linking,
which abort if ever called.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210428170410.479308-25-f4bug@amsat.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/target/mips/tcg/sysemu/special_helper.c b/target/mips/tcg/sysemu/special_helper.c
index 971883fa38..2a2afb49e8 100644
--- a/target/mips/tcg/sysemu/special_helper.c
+++ b/target/mips/tcg/sysemu/special_helper.c
@@ -138,3 +138,36 @@ void helper_deret(CPUMIPSState *env)
 
     debug_post_eret(env);
 }
+
+void helper_cache(CPUMIPSState *env, target_ulong addr, uint32_t op)
+{
+    static const char *const type_name[] = {
+        "Primary Instruction",
+        "Primary Data or Unified Primary",
+        "Tertiary",
+        "Secondary"
+    };
+    uint32_t cache_type = extract32(op, 0, 2);
+    uint32_t cache_operation = extract32(op, 2, 3);
+    target_ulong index = addr & 0x1fffffff;
+
+    switch (cache_operation) {
+    case 0b010: /* Index Store Tag */
+        memory_region_dispatch_write(env->itc_tag, index, env->CP0_TagLo,
+                                     MO_64, MEMTXATTRS_UNSPECIFIED);
+        break;
+    case 0b001: /* Index Load Tag */
+        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:
+        qemu_log_mask(LOG_UNIMP, "cache operation:%u (type: %s cache)\n",
+                      cache_operation, type_name[cache_type]);
+        break;
+    }
+}