mips: Add support for VInt and VEIC irq modes

Signed-off-by: Edgar E. Iglesias <edgar@axis.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/target-mips/helper.c b/target-mips/helper.c
index de2ed7d2c7..bdc1e53669 100644
--- a/target-mips/helper.c
+++ b/target-mips/helper.c
@@ -478,6 +478,33 @@ void do_interrupt (CPUState *env)
         cause = 0;
         if (env->CP0_Cause & (1 << CP0Ca_IV))
             offset = 0x200;
+
+        if (env->CP0_Config3 & ((1 << CP0C3_VInt) | (1 << CP0C3_VEIC))) {
+            /* Vectored Interrupts.  */
+            unsigned int spacing;
+            unsigned int vector;
+            unsigned int pending = (env->CP0_Cause & CP0Ca_IP_mask) >> 8;
+
+            /* Compute the Vector Spacing.  */
+            spacing = (env->CP0_IntCtl >> CP0IntCtl_VS) & ((1 << 6) - 1);
+            spacing <<= 5;
+
+            if (env->CP0_Config3 & (1 << CP0C3_VInt)) {
+                /* For VInt mode, the MIPS computes the vector internally.  */
+                for (vector = 0; vector < 8; vector++) {
+                    if (pending & 1) {
+                        /* Found it.  */
+                        break;
+                    }
+                    pending >>= 1;
+                }
+            } else {
+                /* For VEIC mode, the external interrupt controller feeds the
+                   vector throught the CP0Cause IP lines.  */
+                vector = pending;
+            }
+            offset = 0x200 + vector * spacing;
+        }
         goto set_EPC;
     case EXCP_LTLBL:
         cause = 1;