[src/trunk]: src/sys/arch/arm/omap Don't make the frame buffer BUS_DMA_COHERE...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5d5ecfec4f33
branches:  trunk
changeset: 337325:5d5ecfec4f33
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sat Apr 11 13:44:14 2015 +0000

description:
Don't make the frame buffer BUS_DMA_COHERENT, but instead
do a bus_dmamap_sync() on end-of-frame interrupts.
This effectively cause the frame buffer to be mapped cached,
giving a very noticeable performance boost.

diffstat:

 sys/arch/arm/omap/tifb.c |  20 +++++++++++++++++---
 1 files changed, 17 insertions(+), 3 deletions(-)

diffs (62 lines):

diff -r 42df4e5bd058 -r 5d5ecfec4f33 sys/arch/arm/omap/tifb.c
--- a/sys/arch/arm/omap/tifb.c  Sat Apr 11 13:37:59 2015 +0000
+++ b/sys/arch/arm/omap/tifb.c  Sat Apr 11 13:44:14 2015 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: tifb.c,v 1.3 2014/08/22 20:01:16 jakllsch Exp $        */
+/*     $NetBSD: tifb.c,v 1.4 2015/04/11 13:44:14 bouyer Exp $  */
 
 /*
  * Copyright (c) 2010 Michael Lorenz
@@ -57,7 +57,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: tifb.c,v 1.3 2014/08/22 20:01:16 jakllsch Exp $");
+__KERNEL_RCSID(0, "$NetBSD: tifb.c,v 1.4 2015/04/11 13:44:14 bouyer Exp $");
 
 #include "opt_omap.h"
 
@@ -226,6 +226,7 @@
 static struct evcnt ev_eof1;
 static struct evcnt ev_fifo_underflow;
 static struct evcnt ev_ac_bias;
+static struct evcnt ev_frame_done;
 static struct evcnt ev_others;
 
 
@@ -319,6 +320,8 @@
            "lcd", "fifo underflow");
        evcnt_attach_dynamic(&ev_ac_bias, EVCNT_TYPE_MISC, NULL,
            "lcd", "ac bias");
+       evcnt_attach_dynamic(&ev_frame_done, EVCNT_TYPE_MISC, NULL,
+           "lcd", "frame_done");
        evcnt_attach_dynamic(&ev_others, EVCNT_TYPE_MISC, NULL,
            "lcd", "others");
 
@@ -400,7 +403,7 @@
        }
 
        if (bus_dmamem_map(sc->sc_dmat, sc->sc_dmamem, 1, sc->sc_vramsize,
-           &sc->sc_vramaddr, BUS_DMA_NOWAIT | BUS_DMA_COHERENT) != 0) {
+           &sc->sc_vramaddr, BUS_DMA_NOWAIT) != 0) {
                aprint_error_dev(sc->sc_dev, "failed to map video RAM\n");
                return;
        }
@@ -683,6 +686,17 @@
                return 0;
        }
 
+       if (reg & (IRQ_FRAME_DONE|IRQ_EOF0|IRQ_EOF1)) {
+               /* flush the write-back cache */
+               bus_dmamap_sync(sc->sc_dmat, sc->sc_dmamap,
+                   0, sc->sc_vramsize, BUS_DMASYNC_PREWRITE);
+       }
+
+       if (reg & IRQ_FRAME_DONE) {
+               ev_frame_done.ev_count ++;
+               reg &= ~IRQ_FRAME_DONE;
+       }
+
        if (reg & IRQ_EOF0) {
                ev_eof0.ev_count ++;
                TIFB_WRITE(sc, LCD_LCDDMA_FB0_BASE, sc->sc_dmamem->ds_addr);