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path: root/drivers/dma/sh/rcar-dmac.c
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Diffstat (limited to 'drivers/dma/sh/rcar-dmac.c')
-rw-r--r--drivers/dma/sh/rcar-dmac.c68
1 files changed, 50 insertions, 18 deletions
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
index 2b2c7db3e480..e3ff162c03fc 100644
--- a/drivers/dma/sh/rcar-dmac.c
+++ b/drivers/dma/sh/rcar-dmac.c
@@ -10,6 +10,7 @@
* published by the Free Software Foundation.
*/
+#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/interrupt.h>
@@ -741,6 +742,41 @@ static int rcar_dmac_fill_hwdesc(struct rcar_dmac_chan *chan,
/* -----------------------------------------------------------------------------
* Stop and reset
*/
+static void rcar_dmac_chcr_de_barrier(struct rcar_dmac_chan *chan)
+{
+ u32 chcr;
+ unsigned int i;
+
+ /*
+ * Ensure that the setting of the DE bit is actually 0 after
+ * clearing it.
+ */
+ for (i = 0; i < 1024; i++) {
+ chcr = rcar_dmac_chan_read(chan, RCAR_DMACHCR);
+ if (!(chcr & RCAR_DMACHCR_DE))
+ return;
+ udelay(1);
+ }
+
+ dev_err(chan->chan.device->dev, "CHCR DE check error\n");
+}
+
+static void rcar_dmac_sync_tcr(struct rcar_dmac_chan *chan)
+{
+ u32 chcr = rcar_dmac_chan_read(chan, RCAR_DMACHCR);
+
+ if (!(chcr & RCAR_DMACHCR_DE))
+ return;
+
+ /* set DE=0 and flush remaining data */
+ rcar_dmac_chan_write(chan, RCAR_DMACHCR, (chcr & ~RCAR_DMACHCR_DE));
+
+ /* make sure all remaining data was flushed */
+ rcar_dmac_chcr_de_barrier(chan);
+
+ /* back DE */
+ rcar_dmac_chan_write(chan, RCAR_DMACHCR, chcr);
+}
static void rcar_dmac_chan_halt(struct rcar_dmac_chan *chan)
{
@@ -749,6 +785,7 @@ static void rcar_dmac_chan_halt(struct rcar_dmac_chan *chan)
chcr &= ~(RCAR_DMACHCR_DSE | RCAR_DMACHCR_DSIE | RCAR_DMACHCR_IE |
RCAR_DMACHCR_TE | RCAR_DMACHCR_DE);
rcar_dmac_chan_write(chan, RCAR_DMACHCR, chcr);
+ rcar_dmac_chcr_de_barrier(chan);
}
static void rcar_dmac_chan_reinit(struct rcar_dmac_chan *chan)
@@ -1309,8 +1346,11 @@ static unsigned int rcar_dmac_chan_get_residue(struct rcar_dmac_chan *chan,
residue += chunk->size;
}
+ if (desc->direction == DMA_DEV_TO_MEM)
+ rcar_dmac_sync_tcr(chan);
+
/* Add the residue for the current chunk. */
- residue += rcar_dmac_chan_read(chan, RCAR_DMATCR) << desc->xfer_shift;
+ residue += rcar_dmac_chan_read(chan, RCAR_DMATCRB) << desc->xfer_shift;
return residue;
}
@@ -1481,6 +1521,8 @@ static irqreturn_t rcar_dmac_isr_channel(int irq, void *dev)
if (chcr & RCAR_DMACHCR_TE)
mask |= RCAR_DMACHCR_DE;
rcar_dmac_chan_write(chan, RCAR_DMACHCR, chcr & ~mask);
+ if (mask & RCAR_DMACHCR_DE)
+ rcar_dmac_chcr_de_barrier(chan);
if (chcr & RCAR_DMACHCR_DSE)
ret |= rcar_dmac_isr_desc_stage_end(chan);
@@ -1615,22 +1657,6 @@ static struct dma_chan *rcar_dmac_of_xlate(struct of_phandle_args *dma_spec,
* Power management
*/
-#ifdef CONFIG_PM_SLEEP
-static int rcar_dmac_sleep_suspend(struct device *dev)
-{
- /*
- * TODO: Wait for the current transfer to complete and stop the device.
- */
- return 0;
-}
-
-static int rcar_dmac_sleep_resume(struct device *dev)
-{
- /* TODO: Resume transfers, if any. */
- return 0;
-}
-#endif
-
#ifdef CONFIG_PM
static int rcar_dmac_runtime_suspend(struct device *dev)
{
@@ -1646,7 +1672,13 @@ static int rcar_dmac_runtime_resume(struct device *dev)
#endif
static const struct dev_pm_ops rcar_dmac_pm = {
- SET_SYSTEM_SLEEP_PM_OPS(rcar_dmac_sleep_suspend, rcar_dmac_sleep_resume)
+ /*
+ * TODO for system sleep/resume:
+ * - Wait for the current transfer to complete and stop the device,
+ * - Resume transfers, if any.
+ */
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(rcar_dmac_runtime_suspend, rcar_dmac_runtime_resume,
NULL)
};