[PATCH 6/6] i3c: master: svc: fix random hot join failure since timeout error

Frank Li
2023-10-16T15:33:28Z

master side report:
silvaco-i3c-master 44330000.i3c-master: Error condition: MSTATUS 0x020090c7, MERRWARN 0x00100000

BIT 20: TIMEOUT error
The module has stalled too long in a frame. This happens when:
- The TX FIFO or RX FIFO is not handled and the bus is stuck in the
middle of a message,
- No STOP was issued and between messages,
- IBI manual is used and no decision was made.
The maximum stall period is 10 KHz or 100 μs.

This is a just warning. System irq thread schedule latency is possible
bigger than 100us. Just omit this waring.

Fixes: dd3c52846d59 ("i3c: master: svc: Add Silvaco I3C master driver")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
drivers/i3c/master/svc-i3c-master.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 5bca369d6912..18bc277edc8a 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -93,6 +93,7 @@
#define SVC_I3C_MINTMASKED 0x098
#define SVC_I3C_MERRWARN 0x09C
#define SVC_I3C_MERRWARN_NACK BIT(2)
+#define SVC_I3C_MERRWARN_TIMEOUT BIT(20)
#define SVC_I3C_MDMACTRL 0x0A0
#define SVC_I3C_MDATACTRL 0x0AC
#define SVC_I3C_MDATACTRL_FLUSHTB BIT(0)
@@ -225,6 +226,11 @@ static bool svc_i3c_master_error(struct svc_i3c_master *master)
if (SVC_I3C_MSTATUS_ERRWARN(mstatus)) {
merrwarn = readl(master->regs + SVC_I3C_MERRWARN);
writel(merrwarn, master->regs + SVC_I3C_MERRWARN);
+
+ /* ignore timeout error */
+ if (merrwarn & SVC_I3C_MERRWARN_TIMEOUT)
+ return false;
+
dev_err(master->dev,
"Error condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
mstatus, merrwarn);
--
2.34.1