TCG: Added semantic function for WLFC and WEVT

As QEMU treats internal and external interrupts the same, WEVT is a SLEEP that works for user mode if the Usermode Sleep Flag is set Without SMP, WLFC is like WEVT, but only sleeps if LF is set. WLFC should be revisited when appropriate Signed-off-by: Bruno Mauricio <[email protected]>
foss-for-synopsys-dwc-arc-processors · Mar 15, 2023 · 9635567 · 9635567
1 parent fe1eb0e
commit 9635567
Show file tree

Hide file tree

Showing 2 changed files with 37 additions and 0 deletions.
diff --git a/target/arc/semfunc-mapping.def b/target/arc/semfunc-mapping.def
@@ -539,6 +539,11 @@ MAPPING(rtie, RTIE, 0)
 CONSTANT(SLEEP, sleep, 0, 0)
 MAPPING(sleep, SLEEP, 1, 0)
 
+SEMANTIC_FUNCTION(WEVT, 1)
+MAPPING(wevt, WEVT, 1, 0)
+SEMANTIC_FUNCTION(WLFC, 1)
+MAPPING(wlfc, WLFC, 1, 0)
+
 SEMANTIC_FUNCTION(SWI, 1)
 CONSTANT(SWI, swi, 0, 0)
 MAPPING(swi, SWI, 1, 0)

diff --git a/target/arc/translate.c b/target/arc/translate.c
@@ -1297,6 +1297,38 @@ arc_gen_SLEEP(DisasCtxt *ctx, TCGv a)
     return DISAS_NEXT;
 }
 
+int
+arc_gen_WEVT(DisasCtxt *ctx, TCGv c)
+{
+    arc_gen_except_no_wait_instructions(ctx);
+
+    arc_gen_sleep(ctx, c);
+
+    return DISAS_NEXT;
+}
+
+int
+arc_gen_WLFC(DisasCtxt *ctx, TCGv c)
+{
+    arc_gen_except_no_wait_instructions(ctx);
+
+    /* 
+     * FIXME: When SMP is live, LF being cleared by a different core must
+     * also wakeup WLFC induced sleep
+     */
+    TCGLabel *dont_stop = gen_new_label();
+    TCGv lf_set = tcg_temp_local_new();
+
+    gen_helper_getlf(lf_set, cpu_env);
+    tcg_gen_brcondi_tl(TCG_COND_NE, lf_set, 0x1, dont_stop);
+
+    arc_gen_sleep(ctx, c);
+
+    gen_set_label(dont_stop);
+    tcg_temp_free(lf_set);
+
+    return DISAS_NEXT;
+}
 
 /* Given a CTX, generate the relevant TCG code for the given opcode. */
 static int arc_decode(DisasContext *ctx, const struct arc_opcode *opcode)