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Diffstat (limited to 'arch/arm/plat-omap/dma.c')
-rw-r--r--arch/arm/plat-omap/dma.c19
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 002fb4d..c58d896 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -36,7 +36,6 @@
#include <linux/slab.h>
#include <linux/delay.h>
-#include <asm/system.h>
#include <mach/hardware.h>
#include <plat/dma.h>
@@ -164,6 +163,8 @@ static inline void set_gdma_dev(int req, int dev)
}
#else
#define set_gdma_dev(req, dev) do {} while (0)
+#define omap_readl(reg) 0
+#define omap_writel(val, reg) do {} while (0)
#endif
void omap_set_dma_priority(int lch, int dst_port, int priority)
@@ -915,6 +916,13 @@ void omap_start_dma(int lch)
l |= OMAP_DMA_CCR_BUFFERING_DISABLE;
l |= OMAP_DMA_CCR_EN;
+ /*
+ * As dma_write() uses IO accessors which are weakly ordered, there
+ * is no guarantee that data in coherent DMA memory will be visible
+ * to the DMA device. Add a memory barrier here to ensure that any
+ * such data is visible prior to enabling DMA.
+ */
+ mb();
p->dma_write(l, CCR, lch);
dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
@@ -964,6 +972,13 @@ void omap_stop_dma(int lch)
p->dma_write(l, CCR, lch);
}
+ /*
+ * Ensure that data transferred by DMA is visible to any access
+ * after DMA has been disabled. This is important for coherent
+ * DMA regions.
+ */
+ mb();
+
if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
int next_lch, cur_lch = lch;
char dma_chan_link_map[dma_lch_count];
@@ -2125,7 +2140,7 @@ static int __devexit omap_system_dma_remove(struct platform_device *pdev)
static struct platform_driver omap_system_dma_driver = {
.probe = omap_system_dma_probe,
- .remove = omap_system_dma_remove,
+ .remove = __devexit_p(omap_system_dma_remove),
.driver = {
.name = "omap_dma_system"
},