via: Make sure we flush write-combining using a follow-up read.

Signed-off-by: Dave Airlie <airlied@linux.ie>

diff --git a/drivers/char/drm/via_dma.c b/drivers/char/drm/via_dma.c
index 7635e859b879719dc1ebcd1740facb9c6174085c..13a9c5ca4593546f5eeb504158bf6da9221b51f3 100644 (file)
--- a/drivers/char/drm/via_dma.c
+++ b/drivers/char/drm/via_dma.c
@@ -436,8 +436,10 @@ static int via_hook_segment(drm_via_private_t * dev_priv,
 
        paused = 0;
        via_flush_write_combine();
-       *dev_priv->last_pause_ptr = pause_addr_lo;
+       (void) *(volatile uint32_t *)(via_get_dma(dev_priv) -1);
+       *paused_at = pause_addr_lo;
        via_flush_write_combine();
+       (void) *paused_at;
        reader = *(dev_priv->hw_addr_ptr);
        ptr = ((volatile char *)paused_at - dev_priv->dma_ptr) +
                dev_priv->dma_offset + (uint32_t) dev_priv->agpAddr + 4;
@@ -536,7 +538,7 @@ static void via_cmdbuf_start(drm_via_private_t * dev_priv)
                          &pause_addr_hi, &pause_addr_lo, 1) - 1;
 
        via_flush_write_combine();
-       while(! *dev_priv->last_pause_ptr);
+       (void) *(volatile uint32_t *)dev_priv->last_pause_ptr;
 
        VIA_WRITE(VIA_REG_TRANSET, (HC_ParaType_PreCR << 16));
        VIA_WRITE(VIA_REG_TRANSPACE, command);