Re: [PATCH 2/3] dmaengine: at_xdmac: enhance channel errors handling in tasklet

2019-04-03 Thread Nicolas.Ferre
Vinod,

Thanks for your review, I'm preparing v2.

On 11/02/2019 at 12:58, Vinod Koul wrote:
> On 05-02-19, 12:03, Nicolas Ferre wrote:
>> Complement the identification of errors with stoping the channel and
>> dumping the descriptor that led to the error case.
>>
>> Signed-off-by: Nicolas Ferre 
>> ---
>>   drivers/dma/at_xdmac.c | 43 --
>>   1 file changed, 37 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
>> index 37a269420435..ec7a29d8e448 100644
>> --- a/drivers/dma/at_xdmac.c
>> +++ b/drivers/dma/at_xdmac.c
>> @@ -1575,6 +1575,41 @@ static void at_xdmac_handle_cyclic(struct 
>> at_xdmac_chan *atchan)
>>  dmaengine_desc_get_callback_invoke(txd, NULL);
>>   }
>>   
>> +static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
>> +{
>> +struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
>> +struct at_xdmac_desc*bad_desc;
>> +
>> +/*
>> + * The descriptor currently at the head of the active list is
>> + * broked. Since we don't have any way to report errors, we'll
> 
> You meant borked or broken...

Broken

> 
>> + * just have to scream loudly and try to carry on.
> 
> should we carry on or abort..?

Changed in:

  * just have to scream loudly and try to continue with other
  * descriptors queued (if any).

>> + */
>> +if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
>> +dev_err(chan2dev(>chan), "read bus error!!!");
>> +if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
>> +dev_err(chan2dev(>chan), "write bus error!!!");
>> +if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
>> +dev_err(chan2dev(>chan), "request overflow error!!!");
>> +
>> +spin_lock_bh(>lock);
>> +/* Channel must be disabled first as it's not done automatically */
>> +at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
>> +while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
>> +cpu_relax();
>> +bad_desc = list_first_entry(>xfers_list,
>> +struct at_xdmac_desc,
>> +xfer_node);
>> +spin_unlock_bh(>lock);
>> +/* Print bad descriptor's details if needed */
> 
> Well this is not great to look and read at, please do consider adding
> empty line before comments or logical blocks..

True, indeed.

>> +dev_dbg(chan2dev(>chan),
>> + "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
>> + __func__, _desc->lld.mbr_sa, _desc->lld.mbr_da,
>> + bad_desc->lld.mbr_ubc);
> 
> not dev_err?

Well, we have the dev_err at the beginning of the function, I think it's 
enough: this is really debugging information that needs to be activated 
to track the DMA configuration bug: it's not meant for production.

>> +
>> +/* Then continue with usual descriptor management */
>> +}
>> +
>>   static void at_xdmac_tasklet(unsigned long data)
>>   {
>>  struct at_xdmac_chan*atchan = (struct at_xdmac_chan *)data;
>> @@ -1594,12 +1629,8 @@ static void at_xdmac_tasklet(unsigned long data)
>> || (atchan->irq_status & error_mask)) {
>>  struct dma_async_tx_descriptor  *txd;
>>   
>> -if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
>> -dev_err(chan2dev(>chan), "read bus error!!!");
>> -if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
>> -dev_err(chan2dev(>chan), "write bus error!!!");
>> -if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
>> -dev_err(chan2dev(>chan), "request overflow 
>> error!!!");
>> +if (atchan->irq_status & error_mask)
>> +at_xdmac_handle_error(atchan);
>>   
>>  spin_lock(>lock);
>>  desc = list_first_entry(>xfers_list,
>> -- 
>> 2.17.1
> 


-- 
Nicolas Ferre


Re: [PATCH 2/3] dmaengine: at_xdmac: enhance channel errors handling in tasklet

2019-02-11 Thread Vinod Koul
On 05-02-19, 12:03, Nicolas Ferre wrote:
> Complement the identification of errors with stoping the channel and
> dumping the descriptor that led to the error case.
> 
> Signed-off-by: Nicolas Ferre 
> ---
>  drivers/dma/at_xdmac.c | 43 --
>  1 file changed, 37 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index 37a269420435..ec7a29d8e448 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -1575,6 +1575,41 @@ static void at_xdmac_handle_cyclic(struct 
> at_xdmac_chan *atchan)
>   dmaengine_desc_get_callback_invoke(txd, NULL);
>  }
>  
> +static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
> +{
> + struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
> + struct at_xdmac_desc*bad_desc;
> +
> + /*
> +  * The descriptor currently at the head of the active list is
> +  * broked. Since we don't have any way to report errors, we'll

You meant borked or broken... 

> +  * just have to scream loudly and try to carry on.

should we carry on or abort..?

> +  */
> + if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
> + dev_err(chan2dev(>chan), "read bus error!!!");
> + if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
> + dev_err(chan2dev(>chan), "write bus error!!!");
> + if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
> + dev_err(chan2dev(>chan), "request overflow error!!!");
> +
> + spin_lock_bh(>lock);
> + /* Channel must be disabled first as it's not done automatically */
> + at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
> + while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
> + cpu_relax();
> + bad_desc = list_first_entry(>xfers_list,
> + struct at_xdmac_desc,
> + xfer_node);
> + spin_unlock_bh(>lock);
> + /* Print bad descriptor's details if needed */

Well this is not great to look and read at, please do consider adding
empty line before comments or logical blocks..

> + dev_dbg(chan2dev(>chan),
> +  "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
> +  __func__, _desc->lld.mbr_sa, _desc->lld.mbr_da,
> +  bad_desc->lld.mbr_ubc);

not dev_err?

> +
> + /* Then continue with usual descriptor management */
> +}
> +
>  static void at_xdmac_tasklet(unsigned long data)
>  {
>   struct at_xdmac_chan*atchan = (struct at_xdmac_chan *)data;
> @@ -1594,12 +1629,8 @@ static void at_xdmac_tasklet(unsigned long data)
>  || (atchan->irq_status & error_mask)) {
>   struct dma_async_tx_descriptor  *txd;
>  
> - if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
> - dev_err(chan2dev(>chan), "read bus error!!!");
> - if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
> - dev_err(chan2dev(>chan), "write bus error!!!");
> - if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
> - dev_err(chan2dev(>chan), "request overflow 
> error!!!");
> + if (atchan->irq_status & error_mask)
> + at_xdmac_handle_error(atchan);
>  
>   spin_lock(>lock);
>   desc = list_first_entry(>xfers_list,
> -- 
> 2.17.1

-- 
~Vinod


Re: [PATCH 2/3] dmaengine: at_xdmac: enhance channel errors handling in tasklet

2019-02-05 Thread Ludovic Desroches
On Tue, Feb 05, 2019 at 12:03:42PM +0100, Nicolas Ferre wrote:
> Complement the identification of errors with stoping the channel and
> dumping the descriptor that led to the error case.
> 
> Signed-off-by: Nicolas Ferre 
Acked-by: Ludovic Desroches 

> ---
>  drivers/dma/at_xdmac.c | 43 --
>  1 file changed, 37 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index 37a269420435..ec7a29d8e448 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -1575,6 +1575,41 @@ static void at_xdmac_handle_cyclic(struct 
> at_xdmac_chan *atchan)
>   dmaengine_desc_get_callback_invoke(txd, NULL);
>  }
>  
> +static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
> +{
> + struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
> + struct at_xdmac_desc*bad_desc;
> +
> + /*
> +  * The descriptor currently at the head of the active list is
> +  * broked. Since we don't have any way to report errors, we'll
> +  * just have to scream loudly and try to carry on.
> +  */
> + if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
> + dev_err(chan2dev(>chan), "read bus error!!!");
> + if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
> + dev_err(chan2dev(>chan), "write bus error!!!");
> + if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
> + dev_err(chan2dev(>chan), "request overflow error!!!");
> +
> + spin_lock_bh(>lock);
> + /* Channel must be disabled first as it's not done automatically */
> + at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
> + while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
> + cpu_relax();
> + bad_desc = list_first_entry(>xfers_list,
> + struct at_xdmac_desc,
> + xfer_node);
> + spin_unlock_bh(>lock);
> + /* Print bad descriptor's details if needed */
> + dev_dbg(chan2dev(>chan),
> +  "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
> +  __func__, _desc->lld.mbr_sa, _desc->lld.mbr_da,
> +  bad_desc->lld.mbr_ubc);
> +
> + /* Then continue with usual descriptor management */
> +}
> +
>  static void at_xdmac_tasklet(unsigned long data)
>  {
>   struct at_xdmac_chan*atchan = (struct at_xdmac_chan *)data;
> @@ -1594,12 +1629,8 @@ static void at_xdmac_tasklet(unsigned long data)
>  || (atchan->irq_status & error_mask)) {
>   struct dma_async_tx_descriptor  *txd;
>  
> - if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
> - dev_err(chan2dev(>chan), "read bus error!!!");
> - if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
> - dev_err(chan2dev(>chan), "write bus error!!!");
> - if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
> - dev_err(chan2dev(>chan), "request overflow 
> error!!!");
> + if (atchan->irq_status & error_mask)
> + at_xdmac_handle_error(atchan);
>  
>   spin_lock(>lock);
>   desc = list_first_entry(>xfers_list,
> -- 
> 2.17.1
> 


[PATCH 2/3] dmaengine: at_xdmac: enhance channel errors handling in tasklet

2019-02-05 Thread Nicolas Ferre
Complement the identification of errors with stoping the channel and
dumping the descriptor that led to the error case.

Signed-off-by: Nicolas Ferre 
---
 drivers/dma/at_xdmac.c | 43 --
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index 37a269420435..ec7a29d8e448 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -1575,6 +1575,41 @@ static void at_xdmac_handle_cyclic(struct at_xdmac_chan 
*atchan)
dmaengine_desc_get_callback_invoke(txd, NULL);
 }
 
+static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
+{
+   struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+   struct at_xdmac_desc*bad_desc;
+
+   /*
+* The descriptor currently at the head of the active list is
+* broked. Since we don't have any way to report errors, we'll
+* just have to scream loudly and try to carry on.
+*/
+   if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
+   dev_err(chan2dev(>chan), "read bus error!!!");
+   if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
+   dev_err(chan2dev(>chan), "write bus error!!!");
+   if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
+   dev_err(chan2dev(>chan), "request overflow error!!!");
+
+   spin_lock_bh(>lock);
+   /* Channel must be disabled first as it's not done automatically */
+   at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
+   while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
+   cpu_relax();
+   bad_desc = list_first_entry(>xfers_list,
+   struct at_xdmac_desc,
+   xfer_node);
+   spin_unlock_bh(>lock);
+   /* Print bad descriptor's details if needed */
+   dev_dbg(chan2dev(>chan),
+"%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
+__func__, _desc->lld.mbr_sa, _desc->lld.mbr_da,
+bad_desc->lld.mbr_ubc);
+
+   /* Then continue with usual descriptor management */
+}
+
 static void at_xdmac_tasklet(unsigned long data)
 {
struct at_xdmac_chan*atchan = (struct at_xdmac_chan *)data;
@@ -1594,12 +1629,8 @@ static void at_xdmac_tasklet(unsigned long data)
   || (atchan->irq_status & error_mask)) {
struct dma_async_tx_descriptor  *txd;
 
-   if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
-   dev_err(chan2dev(>chan), "read bus error!!!");
-   if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
-   dev_err(chan2dev(>chan), "write bus error!!!");
-   if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
-   dev_err(chan2dev(>chan), "request overflow 
error!!!");
+   if (atchan->irq_status & error_mask)
+   at_xdmac_handle_error(atchan);
 
spin_lock(>lock);
desc = list_first_entry(>xfers_list,
-- 
2.17.1