diff mbox series

[v2,Resent,3/6] i3c: master: svc: fix ibi may not return mandatory data byte

Message ID 20231018155926.3305476-4-Frank.Li@nxp.com
State New
Headers
Series i3c: master: svc: collection of bugs fixes |

Commit Message

Frank Li Oct. 18, 2023, 3:59 p.m. UTC 
  MSTATUS[RXPEND] is only updated after the data transfer cycle started. This
creates an issue when the I3C clock is slow, and the CPU is running fast
enough that MSTATUS[RXPEND] may not be updated when the code reach checking
point. As a result, mandatory data are being missed.

Add a wait for MSTATUS[COMPLETE] to ensure that all mandatory data is
already in FIFO.

Fixes: dd3c52846d59 ("i3c: master: svc: Add Silvaco I3C master driver")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---

Notes:
    Change from v1 to v2
    - update commit message
      it also works without mandatory bytes

 drivers/i3c/master/svc-i3c-master.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Miquel Raynal Oct. 19, 2023, 6:29 a.m. UTC | #1 
Hi Frank,

Frank.Li@nxp.com wrote on Wed, 18 Oct 2023 11:59:23 -0400:

> MSTATUS[RXPEND] is only updated after the data transfer cycle started. This
> creates an issue when the I3C clock is slow, and the CPU is running fast
> enough that MSTATUS[RXPEND] may not be updated when the code reach checking
> point. As a result, mandatory data are being missed.

reaches

can be missed

> Add a wait for MSTATUS[COMPLETE] to ensure that all mandatory data is
> already in FIFO.
> 
> Fixes: dd3c52846d59 ("i3c: master: svc: Add Silvaco I3C master driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Frank Li <Frank.Li@nxp.com>
> ---
> 
> Notes:
>     Change from v1 to v2
>     - update commit message
>       it also works without mandatory bytes

This could be mentioned in the commit log?

> 
>  drivers/i3c/master/svc-i3c-master.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
> index abebef666b2bb..dd06b7c9333f1 100644
> --- a/drivers/i3c/master/svc-i3c-master.c
> +++ b/drivers/i3c/master/svc-i3c-master.c
> @@ -332,6 +332,7 @@ static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
>  	struct i3c_ibi_slot *slot;
>  	unsigned int count;
>  	u32 mdatactrl;
> +	int ret, val;
>  	u8 *buf;
>  
>  	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
> @@ -341,6 +342,13 @@ static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
>  	slot->len = 0;
>  	buf = slot->data;
>  
> +	ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,
> +						SVC_I3C_MSTATUS_COMPLETE(val), 0, 1000);
> +	if (ret) {
> +		dev_err(master->dev, "Timeout when polling for COMPLETE\n");
> +		return ret;
> +	}
> +
>  	while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS))  &&
>  	       slot->len < SVC_I3C_FIFO_SIZE) {
>  		mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);


Thanks,
Miquèl
diff mbox series

Patch

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index abebef666b2bb..dd06b7c9333f1 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -332,6 +332,7 @@  static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
 	struct i3c_ibi_slot *slot;
 	unsigned int count;
 	u32 mdatactrl;
+	int ret, val;
 	u8 *buf;
 
 	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
@@ -341,6 +342,13 @@  static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
 	slot->len = 0;
 	buf = slot->data;
 
+	ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,
+						SVC_I3C_MSTATUS_COMPLETE(val), 0, 1000);
+	if (ret) {
+		dev_err(master->dev, "Timeout when polling for COMPLETE\n");
+		return ret;
+	}
+
 	while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS))  &&
 	       slot->len < SVC_I3C_FIFO_SIZE) {
 		mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);