powerpc/512x: fix the hanged dma transfer issue
Current code clears interrupt active status _after_ submitting new
transfers. This leaves a possibility of clearing the interrupt for this
new transfer (if it is triggered fast enough) and thus lose this
interrupt. We want to clear interrupt active status _before_ new
transfers is submitted and for current channel only.
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/dma/mpc512x_dma.c b/drivers/dma/mpc512x_dma.c
index 1bc04aa..0717527 100644
--- a/drivers/dma/mpc512x_dma.c
+++ b/drivers/dma/mpc512x_dma.c
@@ -276,6 +276,9 @@
spin_lock(&mchan->lock);
+ out_8(&mdma->regs->dmacint, ch + off);
+ out_8(&mdma->regs->dmacerr, ch + off);
+
/* Check error status */
if (es & (1 << ch))
list_for_each_entry(mdesc, &mchan->active, node)
@@ -309,12 +312,6 @@
mpc_dma_irq_process(mdma, in_be32(&mdma->regs->dmaintl),
in_be32(&mdma->regs->dmaerrl), 0);
- /* Ack interrupt on all channels */
- out_be32(&mdma->regs->dmainth, 0xFFFFFFFF);
- out_be32(&mdma->regs->dmaintl, 0xFFFFFFFF);
- out_be32(&mdma->regs->dmaerrh, 0xFFFFFFFF);
- out_be32(&mdma->regs->dmaerrl, 0xFFFFFFFF);
-
/* Schedule tasklet */
tasklet_schedule(&mdma->tasklet);