Index: pxa2x0_lcd.c
===================================================================
RCS file: /cvsroot/src/sys/arch/arm/xscale/pxa2x0_lcd.c,v
retrieving revision 1.28
diff -u -r1.28 pxa2x0_lcd.c
--- pxa2x0_lcd.c	13 Mar 2010 11:15:52 -0000	1.28
+++ pxa2x0_lcd.c	6 Aug 2010 23:49:18 -0000
@@ -533,9 +533,24 @@
 	}
 
 	error = bus_dmamem_map(dma_tag, scr->segs, scr->nsegs, size,
-	    (void **)&scr->buf_va, busdma_flag | BUS_DMA_COHERENT);
+	    (void **)&scr->buf_va, busdma_flag /*| BUS_DMA_COHERENT*/);
 	if (error)
 		goto bad;
+	{
+		pt_entry_t *ptep;
+		vaddr_t va, eva;
+
+		va = (vaddr_t)scr->buf_va;
+		eva = va + size;
+		while (va < eva) {
+			ptep = vtopte(va);
+			*ptep &= ~L2_S_CACHE_MASK;
+			*ptep |= L2_C;
+			PTE_SYNC(ptep);
+			tlb_flush();
+			va += PAGE_SIZE;
+		}
+	}
 
 	memset(scr->buf_va, 0, scr->buf_size);
 
@@ -582,6 +597,8 @@
 	desc[0].ldcmd |= LDCMD_SOFINT;
 	desc[1].ldcmd |= LDCMD_SOFINT;
 #endif
+	bus_dmamap_sync(dma_tag, scr->dma, 0, size,
+	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
 
 	scr->dma_desc = desc;
 	scr->dma_desc_pa = desc_pa;
@@ -896,7 +913,7 @@
 		return -1;
 
 	return bus_dmamem_mmap(sc->dma_tag, scr->segs, scr->nsegs,
-	    offset, prot, BUS_DMA_WAITOK|BUS_DMA_COHERENT);
+	    offset, prot, BUS_DMA_WAITOK/*|BUS_DMA_COHERENT*/);
 }