From: Sam Nelson <sam.nelson@ti.com>
Date: Tue, 14 Nov 2017 04:03:39 +0000 (-0500)
Subject: ListMP: Add barrier to ensure write backs complete
X-Git-Tag: 3.47.01.00~2
X-Git-Url: https://git.ti.com/gitweb?p=ipc%2Fipcdev.git;a=commitdiff_plain;h=5f3751f632ef92b8370cbc22af927dd32e2302d8;hp=40c347d2a2f03e482f2738ff970fba693e7721a8

ListMP: Add barrier to ensure write backs complete

The call to barrier function is needed to ensure the intended changes
are already written back to memory before leaving the gate to avoid
issues.

Signed-off-by: Sam Nelson <sam.nelson@ti.com>
---

diff --git a/packages/ti/sdo/ipc/ListMP.c b/packages/ti/sdo/ipc/ListMP.c
index 4e89cf8..6b797e4 100644
--- a/packages/ti/sdo/ipc/ListMP.c
+++ b/packages/ti/sdo/ipc/ListMP.c
@@ -79,6 +79,19 @@
  *                       Common Header Functions
  *************************************************************************
  */
+/*
+ *  ======== ListMP_barrier ========
+ *    Function ensures all the writeback to memory is complete
+ */
+static inline void ListMP_barrier(void)
+{
+#if defined(xdc_target__isaCompatible_64P)
+    /* Use _mfence to make sure memory transactions are complete */
+    _mfence();
+    /* Second mfence needed due to errata: See C6670 Advisory 32 */
+    _mfence();
+#endif
+}
 
 /*
  *  ======== ListMP_Params_init ========
@@ -382,6 +395,8 @@ Ptr ListMP_getHead(ListMP_Handle handle)
     if (obj->cacheEnabled) {
         Cache_wbInv(&(attrs->head), sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);
 
@@ -463,6 +478,8 @@ Ptr ListMP_getTail(ListMP_Handle handle)
     if (obj->cacheEnabled) {
         Cache_wbInv(&(attrs->head), sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);
 
@@ -536,6 +553,8 @@ Int ListMP_insert(ListMP_Handle handle, ListMP_Elem *newElem,
         /* writeback invalidate new elem structure  */
         Cache_wbInv(newElem, sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);
 
@@ -678,6 +697,8 @@ Int ListMP_putHead(ListMP_Handle handle, ListMP_Elem *elem)
         /* Write-back because elem->next & elem->prev changed */
         Cache_wbInv(elem, sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);
 
@@ -747,6 +768,8 @@ Int ListMP_putTail(ListMP_Handle handle, ListMP_Elem *elem)
         /* Write-back because elem->next & elem->prev changed */
         Cache_wbInv(elem, sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);
 
@@ -797,6 +820,8 @@ Int ListMP_remove(ListMP_Handle handle, ListMP_Elem *elem)
     if (localNextElemIsCached) {
         Cache_wbInv(localNextElem, sizeof(ListMP_Elem), Cache_Type_ALL, TRUE);
     }
+    else
+        ListMP_barrier();
 
     GateMP_leave((GateMP_Handle)obj->gate, key);