[03/11] cxl/mem: Implement Clear Event Records command

Message ID 20221110185758.879472-4-ira.weiny@intel.com
State New
Headers
Series CXL: Process event logs |

Commit Message

Ira Weiny Nov. 10, 2022, 6:57 p.m. UTC
  From: Ira Weiny <ira.weiny@intel.com>

CXL rev 3.0 section 8.2.9.2.3 defines the Clear Event Records mailbox
command.  After an event record is read it needs to be cleared from the
event log.

Implement cxl_clear_event_record() and call it for each record retrieved
from the device.

Each record is cleared individually.  A clear all bit is specified but
events could arrive between a get and the final clear all operation.
Therefore each event is cleared specifically.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes from RFC:
	Jonathan
		Clean up init of payload and use return code.
		Also report any error to clear the event.
		s/v3.0/rev 3.0
---
 drivers/cxl/core/mbox.c      | 46 ++++++++++++++++++++++++++++++------
 drivers/cxl/cxlmem.h         | 15 ++++++++++++
 include/uapi/linux/cxl_mem.h |  1 +
 3 files changed, 55 insertions(+), 7 deletions(-)
  

Comments

Dave Jiang Nov. 15, 2022, 10:09 p.m. UTC | #1
On 11/10/2022 10:57 AM, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
> 
> CXL rev 3.0 section 8.2.9.2.3 defines the Clear Event Records mailbox
> command.  After an event record is read it needs to be cleared from the
> event log.
> 
> Implement cxl_clear_event_record() and call it for each record retrieved
> from the device.
> 
> Each record is cleared individually.  A clear all bit is specified but
> events could arrive between a get and the final clear all operation.
> Therefore each event is cleared specifically.
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>

Reviewed-by: Dave Jiang <dave.jiang@intel.com>

> 
> ---
> Changes from RFC:
> 	Jonathan
> 		Clean up init of payload and use return code.
> 		Also report any error to clear the event.
> 		s/v3.0/rev 3.0
> ---
>   drivers/cxl/core/mbox.c      | 46 ++++++++++++++++++++++++++++++------
>   drivers/cxl/cxlmem.h         | 15 ++++++++++++
>   include/uapi/linux/cxl_mem.h |  1 +
>   3 files changed, 55 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index a908b95a7de4..f46558e09f08 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -52,6 +52,7 @@ static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
>   #endif
>   	CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
>   	CXL_CMD(GET_EVENT_RECORD, 1, CXL_VARIABLE_PAYLOAD, 0),
> +	CXL_CMD(CLEAR_EVENT_RECORD, CXL_VARIABLE_PAYLOAD, 0, 0),
>   	CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
>   	CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
>   	CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0),
> @@ -708,6 +709,27 @@ int cxl_enumerate_cmds(struct cxl_dev_state *cxlds)
>   }
>   EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
>   
> +static int cxl_clear_event_record(struct cxl_dev_state *cxlds,
> +				  enum cxl_event_log_type log,
> +				  struct cxl_get_event_payload *get_pl, u16 nr)
> +{
> +	struct cxl_mbox_clear_event_payload payload = {
> +		.event_log = log,
> +		.nr_recs = nr,
> +	};
> +	int i;
> +
> +	for (i = 0; i < nr; i++) {
> +		payload.handle[i] = get_pl->record[i].hdr.handle;
> +		dev_dbg(cxlds->dev, "Event log '%s': Clearning %u\n",
> +			cxl_event_log_type_str(log),
> +			le16_to_cpu(payload.handle[i]));
> +	}
> +
> +	return cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_CLEAR_EVENT_RECORD,
> +				 &payload, sizeof(payload), NULL, 0);
> +}
> +
>   static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
>   				    enum cxl_event_log_type type)
>   {
> @@ -728,14 +750,23 @@ static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
>   		}
>   
>   		pl_nr = le16_to_cpu(payload.record_count);
> -		if (trace_cxl_generic_event_enabled()) {
> +		if (pl_nr > 0) {
>   			u16 nr_rec = min_t(u16, pl_nr, CXL_GET_EVENT_NR_RECORDS);
>   			int i;
>   
> -			for (i = 0; i < nr_rec; i++)
> -				trace_cxl_generic_event(dev_name(cxlds->dev),
> -							type,
> -							&payload.record[i]);
> +			if (trace_cxl_generic_event_enabled()) {
> +				for (i = 0; i < nr_rec; i++)
> +					trace_cxl_generic_event(dev_name(cxlds->dev),
> +								type,
> +								&payload.record[i]);
> +			}
> +
> +			rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);
> +			if (rc) {
> +				dev_err(cxlds->dev, "Event log '%s': Failed to clear events : %d",
> +					cxl_event_log_type_str(type), rc);
> +				return;
> +			}
>   		}
>   
>   		if (trace_cxl_overflow_enabled() &&
> @@ -750,10 +781,11 @@ static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
>    * cxl_mem_get_event_records - Get Event Records from the device
>    * @cxlds: The device data for the operation
>    *
> - * Retrieve all event records available on the device and report them as trace
> - * events.
> + * Retrieve all event records available on the device, report them as trace
> + * events, and clear them.
>    *
>    * See CXL rev 3.0 @8.2.9.2.2 Get Event Records
> + * See CXL rev 3.0 @8.2.9.2.3 Clear Event Records
>    */
>   void cxl_mem_get_event_records(struct cxl_dev_state *cxlds)
>   {
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index da64ba0f156b..28a114c7cf69 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -258,6 +258,7 @@ enum cxl_opcode {
>   	CXL_MBOX_OP_INVALID		= 0x0000,
>   	CXL_MBOX_OP_RAW			= CXL_MBOX_OP_INVALID,
>   	CXL_MBOX_OP_GET_EVENT_RECORD	= 0x0100,
> +	CXL_MBOX_OP_CLEAR_EVENT_RECORD	= 0x0101,
>   	CXL_MBOX_OP_GET_FW_INFO		= 0x0200,
>   	CXL_MBOX_OP_ACTIVATE_FW		= 0x0202,
>   	CXL_MBOX_OP_GET_SUPPORTED_LOGS	= 0x0400,
> @@ -397,6 +398,20 @@ static inline const char *cxl_event_log_type_str(enum cxl_event_log_type type)
>   	return "<unknown>";
>   }
>   
> +/*
> + * Clear Event Records input payload
> + * CXL rev 3.0 section 8.2.9.2.3; Table 8-51
> + *
> + * Space given for 1 record
> + */
> +struct cxl_mbox_clear_event_payload {
> +	u8 event_log;		/* enum cxl_event_log_type */
> +	u8 clear_flags;
> +	u8 nr_recs;		/* 1 for this struct */
> +	u8 reserved[3];
> +	__le16 handle[CXL_GET_EVENT_NR_RECORDS];
> +};
> +
>   struct cxl_mbox_get_partition_info {
>   	__le64 active_volatile_cap;
>   	__le64 active_persistent_cap;
> diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
> index 70459be5bdd4..7c1ad8062792 100644
> --- a/include/uapi/linux/cxl_mem.h
> +++ b/include/uapi/linux/cxl_mem.h
> @@ -25,6 +25,7 @@
>   	___C(RAW, "Raw device command"),                                  \
>   	___C(GET_SUPPORTED_LOGS, "Get Supported Logs"),                   \
>   	___C(GET_EVENT_RECORD, "Get Event Record"),                       \
> +	___C(CLEAR_EVENT_RECORD, "Clear Event Record"),                   \
>   	___C(GET_FW_INFO, "Get FW Info"),                                 \
>   	___C(GET_PARTITION_INFO, "Get Partition Information"),            \
>   	___C(GET_LSA, "Get Label Storage Area"),                          \
  
Jonathan Cameron Nov. 16, 2022, 3:24 p.m. UTC | #2
On Thu, 10 Nov 2022 10:57:50 -0800
ira.weiny@intel.com wrote:

> From: Ira Weiny <ira.weiny@intel.com>
> 
> CXL rev 3.0 section 8.2.9.2.3 defines the Clear Event Records mailbox
> command.  After an event record is read it needs to be cleared from the
> event log.
> 
> Implement cxl_clear_event_record() and call it for each record retrieved
> from the device.
> 
> Each record is cleared individually.  A clear all bit is specified but
> events could arrive between a get and the final clear all operation.
> Therefore each event is cleared specifically.
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> 
Some follow through comment updates needed from changes in earlier patches +
one comment you can ignore if you prefer to keep it as is.

>  static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
>  				    enum cxl_event_log_type type)
>  {
> @@ -728,14 +750,23 @@ static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
>  		}
>  
>  		pl_nr = le16_to_cpu(payload.record_count);
> -		if (trace_cxl_generic_event_enabled()) {

To simplify this patch, maybe push this check down in the previous patch so this
one doesn't move code around?  It'll look a tiny bit odd there of course..

> +		if (pl_nr > 0) {
>  			u16 nr_rec = min_t(u16, pl_nr, CXL_GET_EVENT_NR_RECORDS);
>  			int i;
>  
> -			for (i = 0; i < nr_rec; i++)
> -				trace_cxl_generic_event(dev_name(cxlds->dev),
> -							type,
> -							&payload.record[i]);
> +			if (trace_cxl_generic_event_enabled()) {
> +				for (i = 0; i < nr_rec; i++)
> +					trace_cxl_generic_event(dev_name(cxlds->dev),
> +								type,
> +								&payload.record[i]);
> +			}
> +
> +			rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);
> +			if (rc) {
> +				dev_err(cxlds->dev, "Event log '%s': Failed to clear events : %d",
> +					cxl_event_log_type_str(type), rc);
> +				return;
> +			}
>  		}
>  

> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index da64ba0f156b..28a114c7cf69 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h

>  
> +/*
> + * Clear Event Records input payload
> + * CXL rev 3.0 section 8.2.9.2.3; Table 8-51
> + *
> + * Space given for 1 record

Nope...


> + */
> +struct cxl_mbox_clear_event_payload {
> +	u8 event_log;		/* enum cxl_event_log_type */
> +	u8 clear_flags;
> +	u8 nr_recs;		/* 1 for this struct */
Nope :)  Delete the comments so they can't be wrong if this changes in future!

> +	u8 reserved[3];
> +	__le16 handle[CXL_GET_EVENT_NR_RECORDS];
> +};
> +
  
Jonathan Cameron Nov. 16, 2022, 3:45 p.m. UTC | #3
On Wed, 16 Nov 2022 15:24:26 +0000
Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote:

> On Thu, 10 Nov 2022 10:57:50 -0800
> ira.weiny@intel.com wrote:
> 
> > From: Ira Weiny <ira.weiny@intel.com>
> > 
> > CXL rev 3.0 section 8.2.9.2.3 defines the Clear Event Records mailbox
> > command.  After an event record is read it needs to be cleared from the
> > event log.
> > 
> > Implement cxl_clear_event_record() and call it for each record retrieved
> > from the device.
> > 
> > Each record is cleared individually.  A clear all bit is specified but
> > events could arrive between a get and the final clear all operation.
> > Therefore each event is cleared specifically.
> > 
> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> >   
> Some follow through comment updates needed from changes in earlier patches +
> one comment you can ignore if you prefer to keep it as is.
> 
> >  static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
> >  				    enum cxl_event_log_type type)
> >  {
> > @@ -728,14 +750,23 @@ static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
> >  		}
> >  
> >  		pl_nr = le16_to_cpu(payload.record_count);
> > -		if (trace_cxl_generic_event_enabled()) {  
> 
> To simplify this patch, maybe push this check down in the previous patch so this
> one doesn't move code around?  It'll look a tiny bit odd there of course..
> 
> > +		if (pl_nr > 0) {
> >  			u16 nr_rec = min_t(u16, pl_nr, CXL_GET_EVENT_NR_RECORDS);
> >  			int i;
> >  
> > -			for (i = 0; i < nr_rec; i++)
> > -				trace_cxl_generic_event(dev_name(cxlds->dev),
> > -							type,
> > -							&payload.record[i]);
> > +			if (trace_cxl_generic_event_enabled()) {
> > +				for (i = 0; i < nr_rec; i++)
> > +					trace_cxl_generic_event(dev_name(cxlds->dev),
> > +								type,
> > +								&payload.record[i]);
> > +			}
> > +
> > +			rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);
> > +			if (rc) {
> > +				dev_err(cxlds->dev, "Event log '%s': Failed to clear events : %d",
> > +					cxl_event_log_type_str(type), rc);
> > +				return;
> > +			}
> >  		}
> >    
> 
> > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> > index da64ba0f156b..28a114c7cf69 100644
> > --- a/drivers/cxl/cxlmem.h
> > +++ b/drivers/cxl/cxlmem.h  
> 
> >  
> > +/*
> > + * Clear Event Records input payload
> > + * CXL rev 3.0 section 8.2.9.2.3; Table 8-51
> > + *
> > + * Space given for 1 record  
> 
> Nope...
> 
> 
> > + */
> > +struct cxl_mbox_clear_event_payload {
> > +	u8 event_log;		/* enum cxl_event_log_type */
> > +	u8 clear_flags;
> > +	u8 nr_recs;		/* 1 for this struct */  
> Nope :)  Delete the comments so they can't be wrong if this changes in future!
Ah. You only use one. So should hard code that in the array size below.

> 
> > +	u8 reserved[3];
> > +	__le16 handle[CXL_GET_EVENT_NR_RECORDS];
> > +};
> > +  
>
  
Ira Weiny Nov. 17, 2022, 1:07 a.m. UTC | #4
On Wed, Nov 16, 2022 at 03:24:26PM +0000, Jonathan Cameron wrote:
> On Thu, 10 Nov 2022 10:57:50 -0800
> ira.weiny@intel.com wrote:
> 
> > From: Ira Weiny <ira.weiny@intel.com>
> > 
> > CXL rev 3.0 section 8.2.9.2.3 defines the Clear Event Records mailbox
> > command.  After an event record is read it needs to be cleared from the
> > event log.
> > 
> > Implement cxl_clear_event_record() and call it for each record retrieved
> > from the device.
> > 
> > Each record is cleared individually.  A clear all bit is specified but
> > events could arrive between a get and the final clear all operation.
> > Therefore each event is cleared specifically.
> > 
> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> > 
> Some follow through comment updates needed from changes in earlier patches +
> one comment you can ignore if you prefer to keep it as is.
> 
> >  static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
> >  				    enum cxl_event_log_type type)
> >  {
> > @@ -728,14 +750,23 @@ static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
> >  		}
> >  
> >  		pl_nr = le16_to_cpu(payload.record_count);
> > -		if (trace_cxl_generic_event_enabled()) {
> 
> To simplify this patch, maybe push this check down in the previous patch so this
> one doesn't move code around?  It'll look a tiny bit odd there of course..

That is the issue I think the oddness is easier to defend here vs having it in
the previous patch.

> 
> > +		if (pl_nr > 0) {
> >  			u16 nr_rec = min_t(u16, pl_nr, CXL_GET_EVENT_NR_RECORDS);
> >  			int i;
> >  
> > -			for (i = 0; i < nr_rec; i++)
> > -				trace_cxl_generic_event(dev_name(cxlds->dev),
> > -							type,
> > -							&payload.record[i]);
> > +			if (trace_cxl_generic_event_enabled()) {
> > +				for (i = 0; i < nr_rec; i++)
> > +					trace_cxl_generic_event(dev_name(cxlds->dev),
> > +								type,
> > +								&payload.record[i]);
> > +			}
> > +
> > +			rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);
> > +			if (rc) {
> > +				dev_err(cxlds->dev, "Event log '%s': Failed to clear events : %d",
> > +					cxl_event_log_type_str(type), rc);
> > +				return;
> > +			}
> >  		}
> >  
> 
> > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> > index da64ba0f156b..28a114c7cf69 100644
> > --- a/drivers/cxl/cxlmem.h
> > +++ b/drivers/cxl/cxlmem.h
> 
> >  
> > +/*
> > + * Clear Event Records input payload
> > + * CXL rev 3.0 section 8.2.9.2.3; Table 8-51
> > + *
> > + * Space given for 1 record
> 
> Nope...

<sigh> yep...  ;-)

> 
> 
> > + */
> > +struct cxl_mbox_clear_event_payload {
> > +	u8 event_log;		/* enum cxl_event_log_type */
> > +	u8 clear_flags;
> > +	u8 nr_recs;		/* 1 for this struct */
> Nope :)  Delete the comments so they can't be wrong if this changes in future!

Yep.  :-/

Ira
  
Ira Weiny Nov. 17, 2022, 1:12 a.m. UTC | #5
On Wed, Nov 16, 2022 at 03:45:43PM +0000, Jonathan Cameron wrote:
> On Wed, 16 Nov 2022 15:24:26 +0000
> Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote:
> 

[snip]

> > 
> > 
> > > + */
> > > +struct cxl_mbox_clear_event_payload {
> > > +	u8 event_log;		/* enum cxl_event_log_type */
> > > +	u8 clear_flags;
> > > +	u8 nr_recs;		/* 1 for this struct */  
> > Nope :)  Delete the comments so they can't be wrong if this changes in future!
> Ah. You only use one. So should hard code that in the array size below.

No it can can send up to CXL_GET_EVENT_NR_RECORDS at a time : 'nr_rec'.


                        rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);


static int cxl_clear_event_record(struct cxl_dev_state *cxlds,                                                                  
                                  enum cxl_event_log_type log,                                                                  
                                  struct cxl_get_event_payload *get_pl, u16 nr)                                                 
{                                                                                                                               
        struct cxl_mbox_clear_event_payload payload = {                                                                         
                .event_log = log,                                                                                               
                .nr_recs = nr,                                                                                                  
                ^^^^^^^^^^^^^^
                Here...

        };                                                                                                                      
        int i;                                                                                                                  
                                                                                                                                
        for (i = 0; i < nr; i++) {                                                                                              
                payload.handle[i] = get_pl->record[i].hdr.handle;                                                               
                dev_dbg(cxlds->dev, "Event log '%s': Clearning %u\n",                                                           
                        cxl_event_log_type_str(log),                                                                            
                        le16_to_cpu(payload.handle[i]));                                                                        
        }                                                                                                                       
...

Ira
  

Patch

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index a908b95a7de4..f46558e09f08 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -52,6 +52,7 @@  static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = {
 #endif
 	CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE),
 	CXL_CMD(GET_EVENT_RECORD, 1, CXL_VARIABLE_PAYLOAD, 0),
+	CXL_CMD(CLEAR_EVENT_RECORD, CXL_VARIABLE_PAYLOAD, 0, 0),
 	CXL_CMD(GET_FW_INFO, 0, 0x50, 0),
 	CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0),
 	CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0),
@@ -708,6 +709,27 @@  int cxl_enumerate_cmds(struct cxl_dev_state *cxlds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL);
 
+static int cxl_clear_event_record(struct cxl_dev_state *cxlds,
+				  enum cxl_event_log_type log,
+				  struct cxl_get_event_payload *get_pl, u16 nr)
+{
+	struct cxl_mbox_clear_event_payload payload = {
+		.event_log = log,
+		.nr_recs = nr,
+	};
+	int i;
+
+	for (i = 0; i < nr; i++) {
+		payload.handle[i] = get_pl->record[i].hdr.handle;
+		dev_dbg(cxlds->dev, "Event log '%s': Clearning %u\n",
+			cxl_event_log_type_str(log),
+			le16_to_cpu(payload.handle[i]));
+	}
+
+	return cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_CLEAR_EVENT_RECORD,
+				 &payload, sizeof(payload), NULL, 0);
+}
+
 static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
 				    enum cxl_event_log_type type)
 {
@@ -728,14 +750,23 @@  static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
 		}
 
 		pl_nr = le16_to_cpu(payload.record_count);
-		if (trace_cxl_generic_event_enabled()) {
+		if (pl_nr > 0) {
 			u16 nr_rec = min_t(u16, pl_nr, CXL_GET_EVENT_NR_RECORDS);
 			int i;
 
-			for (i = 0; i < nr_rec; i++)
-				trace_cxl_generic_event(dev_name(cxlds->dev),
-							type,
-							&payload.record[i]);
+			if (trace_cxl_generic_event_enabled()) {
+				for (i = 0; i < nr_rec; i++)
+					trace_cxl_generic_event(dev_name(cxlds->dev),
+								type,
+								&payload.record[i]);
+			}
+
+			rc = cxl_clear_event_record(cxlds, type, &payload, nr_rec);
+			if (rc) {
+				dev_err(cxlds->dev, "Event log '%s': Failed to clear events : %d",
+					cxl_event_log_type_str(type), rc);
+				return;
+			}
 		}
 
 		if (trace_cxl_overflow_enabled() &&
@@ -750,10 +781,11 @@  static void cxl_mem_get_records_log(struct cxl_dev_state *cxlds,
  * cxl_mem_get_event_records - Get Event Records from the device
  * @cxlds: The device data for the operation
  *
- * Retrieve all event records available on the device and report them as trace
- * events.
+ * Retrieve all event records available on the device, report them as trace
+ * events, and clear them.
  *
  * See CXL rev 3.0 @8.2.9.2.2 Get Event Records
+ * See CXL rev 3.0 @8.2.9.2.3 Clear Event Records
  */
 void cxl_mem_get_event_records(struct cxl_dev_state *cxlds)
 {
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index da64ba0f156b..28a114c7cf69 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -258,6 +258,7 @@  enum cxl_opcode {
 	CXL_MBOX_OP_INVALID		= 0x0000,
 	CXL_MBOX_OP_RAW			= CXL_MBOX_OP_INVALID,
 	CXL_MBOX_OP_GET_EVENT_RECORD	= 0x0100,
+	CXL_MBOX_OP_CLEAR_EVENT_RECORD	= 0x0101,
 	CXL_MBOX_OP_GET_FW_INFO		= 0x0200,
 	CXL_MBOX_OP_ACTIVATE_FW		= 0x0202,
 	CXL_MBOX_OP_GET_SUPPORTED_LOGS	= 0x0400,
@@ -397,6 +398,20 @@  static inline const char *cxl_event_log_type_str(enum cxl_event_log_type type)
 	return "<unknown>";
 }
 
+/*
+ * Clear Event Records input payload
+ * CXL rev 3.0 section 8.2.9.2.3; Table 8-51
+ *
+ * Space given for 1 record
+ */
+struct cxl_mbox_clear_event_payload {
+	u8 event_log;		/* enum cxl_event_log_type */
+	u8 clear_flags;
+	u8 nr_recs;		/* 1 for this struct */
+	u8 reserved[3];
+	__le16 handle[CXL_GET_EVENT_NR_RECORDS];
+};
+
 struct cxl_mbox_get_partition_info {
 	__le64 active_volatile_cap;
 	__le64 active_persistent_cap;
diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h
index 70459be5bdd4..7c1ad8062792 100644
--- a/include/uapi/linux/cxl_mem.h
+++ b/include/uapi/linux/cxl_mem.h
@@ -25,6 +25,7 @@ 
 	___C(RAW, "Raw device command"),                                  \
 	___C(GET_SUPPORTED_LOGS, "Get Supported Logs"),                   \
 	___C(GET_EVENT_RECORD, "Get Event Record"),                       \
+	___C(CLEAR_EVENT_RECORD, "Clear Event Record"),                   \
 	___C(GET_FW_INFO, "Get FW Info"),                                 \
 	___C(GET_PARTITION_INFO, "Get Partition Information"),            \
 	___C(GET_LSA, "Get Label Storage Area"),                          \