Radeon EXA: wait for the engine to be idle before sw access

Really we need proper fencing with timestamps but this should
help in the short term.

This should help with minor corruption issues and possibly
lockups.

4 files changed, 31 insertions, 4 deletions

diff --git a/src/radeon.h b/src/radeon.h
index 66b23304..633385f5 100644
--- a/src/radeon.h
+++ b/src/radeon.h
@@ -893,6 +893,7 @@ extern void RADEONEngineFlush(ScrnInfoPtr pScrn);
 extern void RADEONEngineInit(ScrnInfoPtr pScrn);
 extern void RADEONEngineReset(ScrnInfoPtr pScrn);
 extern void RADEONEngineRestore(ScrnInfoPtr pScrn);
+extern Bool RADEONWaitforIdlePoll(ScrnInfoPtr pScrn);
 extern uint8_t *RADEONHostDataBlit(ScrnInfoPtr pScrn, unsigned int cpp,
 				 unsigned int w, uint32_t dstPitchOff,
 				 uint32_t *bufPitch, int x, int *y,
diff --git a/src/radeon_accel.c b/src/radeon_accel.c
index 96570e8c..d2ae2e69 100644
--- a/src/radeon_accel.c
+++ b/src/radeon_accel.c
@@ -472,6 +472,23 @@ void RADEONEngineInit(ScrnInfoPtr pScrn)
     RADEONEngineRestore(pScrn);
 }
 
+/* really would be better to wait on a timestamp shadowed in memory,
+ * but this will do for now.
+ */
+Bool
+RADEONWaitforIdlePoll(ScrnInfoPtr pScrn)
+{
+    RADEONInfoPtr info = RADEONPTR(pScrn);
+    unsigned char *RADEONMMIO = info->MMIO;
+    uint32_t i;
+
+    for (i = 0; i < 1000000; i++) {
+	if ((INREG(RADEON_RBBM_STATUS) & RADEON_RBBM_ACTIVE) == 0)
+	    return TRUE;
+    }
+    return FALSE;
+}
+
 
 #define ACCEL_MMIO
 #define ACCEL_PREAMBLE()        unsigned char *RADEONMMIO = info->MMIO
@@ -872,6 +889,8 @@ RADEONHostDataBlitCopyPass(
     /* RADEONHostDataBlitCopy can return NULL ! */
     if( (dst==NULL) || (src==NULL)) return;
 
+    RADEONWaitforIdlePoll(pScrn);
+
     if ( dstPitch == srcPitch )
     {
 #if X_BYTE_ORDER == X_BIG_ENDIAN
diff --git a/src/radeon_exa.c b/src/radeon_exa.c
index c4bc1bb1..ebe65d1d 100644
--- a/src/radeon_exa.c
+++ b/src/radeon_exa.c
@@ -220,17 +220,22 @@ int RADEONBiggerCrtcArea(PixmapPtr pPix)
 }
 
 #if X_BYTE_ORDER == X_BIG_ENDIAN
-
 static unsigned long swapper_surfaces[3];
+#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
 
 static Bool RADEONPrepareAccess(PixmapPtr pPix, int index)
 {
     RINFO_FROM_SCREEN(pPix->drawable.pScreen);
+#if X_BYTE_ORDER == X_BIG_ENDIAN
     unsigned char *RADEONMMIO = info->MMIO;
     uint32_t offset = exaGetPixmapOffset(pPix);
     int bpp, soff;
     uint32_t size, flags;
+#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
+
+    RADEONWaitforIdlePoll(pScrn);
 
+#if X_BYTE_ORDER == X_BIG_ENDIAN
     /* Front buffer is always set with proper swappers */
     if (offset == 0)
         return TRUE;
@@ -286,11 +291,13 @@ static Bool RADEONPrepareAccess(PixmapPtr pPix, int index)
     OUTREG(RADEON_SURFACE0_LOWER_BOUND + soff, offset);
     OUTREG(RADEON_SURFACE0_UPPER_BOUND + soff, offset + size - 1);
     swapper_surfaces[index] = offset;
+#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
     return TRUE;
 }
 
 static void RADEONFinishAccess(PixmapPtr pPix, int index)
 {
+#if X_BYTE_ORDER == X_BIG_ENDIAN
     RINFO_FROM_SCREEN(pPix->drawable.pScreen);
     unsigned char *RADEONMMIO = info->MMIO;
     uint32_t offset = exaGetPixmapOffset(pPix);
@@ -318,9 +325,9 @@ static void RADEONFinishAccess(PixmapPtr pPix, int index)
     OUTREG(RADEON_SURFACE0_LOWER_BOUND + soff, 0);
     OUTREG(RADEON_SURFACE0_UPPER_BOUND + soff, 0);
     swapper_surfaces[index] = 0;
+#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
 }
 
-#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
 
 #define ENTER_DRAW(x) TRACE
 #define LEAVE_DRAW(x) TRACE
diff --git a/src/radeon_exa_funcs.c b/src/radeon_exa_funcs.c
index cd97cc6e..eb714ab6 100644
--- a/src/radeon_exa_funcs.c
+++ b/src/radeon_exa_funcs.c
@@ -408,6 +408,8 @@ RADEONDownloadFromScreenCP(PixmapPtr pSrc, int x, int y, int w, int h,
 	    while ((drmCommandNone(info->dri->drmFD, DRM_RADEON_CP_IDLE) == -EBUSY)
 		   && (i++ < RADEON_TIMEOUT))
 		;
+	    /* make sure the engine is idle */
+	    RADEONWaitforIdlePoll(pScrn);
 
 	    /* Kick next blit */
 	    if (hpass)
@@ -470,10 +472,8 @@ Bool FUNC_NAME(RADEONDrawInit)(ScreenPtr pScreen)
 	info->accel_state->exa->DownloadFromScreen = RADEONDownloadFromScreenCP;
 #endif
 
-#if X_BYTE_ORDER == X_BIG_ENDIAN
     info->accel_state->exa->PrepareAccess = RADEONPrepareAccess;
     info->accel_state->exa->FinishAccess = RADEONFinishAccess;
-#endif /* X_BYTE_ORDER == X_BIG_ENDIAN */
 
     info->accel_state->exa->flags = EXA_OFFSCREEN_PIXMAPS;
     info->accel_state->exa->pixmapOffsetAlign = RADEON_BUFFER_ALIGN + 1;