diff mbox series

[1/3] dmaengine: apple-admac: Handle 'global' interrupt flags

Message ID 20230224152222.26732-1-povik+lin@cutebit.org
State New
Headers
Series [1/3] dmaengine: apple-admac: Handle 'global' interrupt flags |

Commit Message

Martin Povišer Feb. 24, 2023, 3:22 p.m. UTC 
  In addition to TX channel and RX channel interrupt flags there's
another class of 'global' interrupt flags with unknown semantics. Those
weren't being handled up to now, and they are the suspected cause of
stuck IRQ states that have been sporadically occurring. Check the global
flags and clear them if raised.

Fixes: b127315d9a78 ("dmaengine: apple-admac: Add Apple ADMAC driver")
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
---
 drivers/dma/apple-admac.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

Comments

Vinod Koul March 31, 2023, 12:47 p.m. UTC | #1 
On 24-02-23, 16:22, Martin Povišer wrote:
> In addition to TX channel and RX channel interrupt flags there's
> another class of 'global' interrupt flags with unknown semantics. Those
> weren't being handled up to now, and they are the suspected cause of
> stuck IRQ states that have been sporadically occurring. Check the global
> flags and clear them if raised.

Applied, thanks
diff mbox series

Patch

diff --git a/drivers/dma/apple-admac.c b/drivers/dma/apple-admac.c
index 90f28bda29c8..00cbfafe0ed9 100644
--- a/drivers/dma/apple-admac.c
+++ b/drivers/dma/apple-admac.c
@@ -75,6 +75,7 @@ 
 
 #define REG_TX_INTSTATE(idx)		(0x0030 + (idx) * 4)
 #define REG_RX_INTSTATE(idx)		(0x0040 + (idx) * 4)
+#define REG_GLOBAL_INTSTATE(idx)	(0x0050 + (idx) * 4)
 #define REG_CHAN_INTSTATUS(ch, idx)	(0x8010 + (ch) * 0x200 + (idx) * 4)
 #define REG_CHAN_INTMASK(ch, idx)	(0x8020 + (ch) * 0x200 + (idx) * 4)
 
@@ -672,13 +673,14 @@  static void admac_handle_chan_int(struct admac_data *ad, int no)
 static irqreturn_t admac_interrupt(int irq, void *devid)
 {
 	struct admac_data *ad = devid;
-	u32 rx_intstate, tx_intstate;
+	u32 rx_intstate, tx_intstate, global_intstate;
 	int i;
 
 	rx_intstate = readl_relaxed(ad->base + REG_RX_INTSTATE(ad->irq_index));
 	tx_intstate = readl_relaxed(ad->base + REG_TX_INTSTATE(ad->irq_index));
+	global_intstate = readl_relaxed(ad->base + REG_GLOBAL_INTSTATE(ad->irq_index));
 
-	if (!tx_intstate && !rx_intstate)
+	if (!tx_intstate && !rx_intstate && !global_intstate)
 		return IRQ_NONE;
 
 	for (i = 0; i < ad->nchannels; i += 2) {
@@ -693,6 +695,12 @@  static irqreturn_t admac_interrupt(int irq, void *devid)
 		rx_intstate >>= 1;
 	}
 
+	if (global_intstate) {
+		dev_warn(ad->dev, "clearing unknown global interrupt flag: %x\n",
+			 global_intstate);
+		writel_relaxed(~(u32) 0, ad->base + REG_GLOBAL_INTSTATE(ad->irq_index));
+	}
+
 	return IRQ_HANDLED;
 }