From: Alex Crowther <alex.crowther@imgtec.com>
Date: Mon, 23 May 2011 11:46:17 +0000 (+0100)
Subject: gpu: pvr: V2: Find and fix all incorrect sync counter completion checks
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=39828db15f6680fbe6beea814eea20fdf9314d97;p=sgx.git

gpu: pvr: V2: Find and fix all incorrect sync counter completion checks

Bugfix for a very rare buffer wrap issue on sync counters
though the use of the wrap safe sync_cnt_after_eq function

Fixes: NB#233069
Signed-off-by: Alex Crowther <alex.crowther@imgtec.com>
---

diff --git a/pvr/sgxutils.c b/pvr/sgxutils.c
index 860cbb6..b5e5b7d 100644
--- a/pvr/sgxutils.c
+++ b/pvr/sgxutils.c
@@ -644,16 +644,26 @@ enum PVRSRV_ERROR SGXUnregisterHWTransferContextKM(void *hHWTransferContext)
 	return PVRSRV_OK;
 }
 
+
+
+static inline int sync_cnt_after_eq(u32 c1, u32 c2)
+{
+	return (int)(c1 - c2) >= 0;
+}
+
+
+
 static inline IMG_BOOL SGX2DQuerySyncOpsComplete(
 				struct PVRSRV_KERNEL_SYNC_INFO *psSyncInfo,
 				u32 ui32ReadOpsPending, u32 ui32WriteOpsPending)
 {
 	struct PVRSRV_SYNC_DATA *psSyncData = psSyncInfo->psSyncData;
 
-	return (IMG_BOOL)((psSyncData->ui32ReadOpsComplete >=
-				ui32ReadOpsPending) &&
-			   (psSyncData->ui32WriteOpsComplete >=
-				ui32WriteOpsPending));
+	return (IMG_BOOL)(
+		sync_cnt_after_eq(
+			psSyncData->ui32ReadOpsComplete, ui32ReadOpsPending) &&
+		sync_cnt_after_eq(
+			psSyncData->ui32WriteOpsComplete, ui32WriteOpsPending));
 }
 
 enum PVRSRV_ERROR SGX2DQueryBlitsCompleteKM(