+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);
+}