diff mbox series

[v4,19/28] cxl/mem: Configure dynamic capacity interrupts

Message ID 20241007-dcd-type2-upstream-v4-19-c261ee6eeded@intel.com (mailing list archive)
State New, archived
Headers show
Series DCD: Add support for Dynamic Capacity Devices (DCD) | expand

Commit Message

Ira Weiny Oct. 7, 2024, 11:16 p.m. UTC
From: Navneet Singh <navneet.singh@intel.com>

Dynamic Capacity Devices (DCD) support extent change notifications
through the event log mechanism.  The interrupt mailbox commands were
extended in CXL 3.1 to support these notifications.  Firmware can't
configure DCD events to be FW controlled but can retain control of
memory events.

Configure DCD event log interrupts on devices supporting dynamic
capacity.  Disable DCD if interrupts are not supported.

Care is taken to preserve the interrupt policy set by the FW if FW first
has been selected by the BIOS.

Signed-off-by: Navneet Singh <navneet.singh@intel.com>
Co-developed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>

---
Changes:
[iweiny: rebase on 6.12]
---
 drivers/cxl/cxlmem.h |  2 ++
 drivers/cxl/pci.c    | 72 +++++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 62 insertions(+), 12 deletions(-)

Comments

Jonathan Cameron Oct. 10, 2024, 2:15 p.m. UTC | #1
On Mon, 07 Oct 2024 18:16:25 -0500
ira.weiny@intel.com wrote:

> From: Navneet Singh <navneet.singh@intel.com>
> 
> Dynamic Capacity Devices (DCD) support extent change notifications
> through the event log mechanism.  The interrupt mailbox commands were
> extended in CXL 3.1 to support these notifications.  Firmware can't
> configure DCD events to be FW controlled but can retain control of
> memory events.
> 
> Configure DCD event log interrupts on devices supporting dynamic
> capacity.  Disable DCD if interrupts are not supported.
> 
> Care is taken to preserve the interrupt policy set by the FW if FW first
> has been selected by the BIOS.
> 
> Signed-off-by: Navneet Singh <navneet.singh@intel.com>
> Co-developed-by: Ira Weiny <ira.weiny@intel.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Ah. I was wondering why policy needed to be initialize to zero outside
this call.  Maybe moving it in here with a memset() would be cleaner.

Either way
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Fan Ni Oct. 10, 2024, 6:25 p.m. UTC | #2
On Mon, Oct 07, 2024 at 06:16:25PM -0500, ira.weiny@intel.com wrote:
> From: Navneet Singh <navneet.singh@intel.com>
> 
> Dynamic Capacity Devices (DCD) support extent change notifications
> through the event log mechanism.  The interrupt mailbox commands were
> extended in CXL 3.1 to support these notifications.  Firmware can't
> configure DCD events to be FW controlled but can retain control of
> memory events.
> 
> Configure DCD event log interrupts on devices supporting dynamic
> capacity.  Disable DCD if interrupts are not supported.
> 
> Care is taken to preserve the interrupt policy set by the FW if FW first
> has been selected by the BIOS.
> 
> Signed-off-by: Navneet Singh <navneet.singh@intel.com>
> Co-developed-by: Ira Weiny <ira.weiny@intel.com>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> 
> ---
> Changes:
> [iweiny: rebase on 6.12]
> ---
>  drivers/cxl/cxlmem.h |  2 ++
>  drivers/cxl/pci.c    | 72 +++++++++++++++++++++++++++++++++++++++++++---------
>  2 files changed, 62 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index c3b889a586d8..2d2a1884a174 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -226,7 +226,9 @@ struct cxl_event_interrupt_policy {
>  	u8 warn_settings;
>  	u8 failure_settings;
>  	u8 fatal_settings;
> +	u8 dcd_settings;
>  } __packed;
> +#define CXL_EVENT_INT_POLICY_BASE_SIZE 4 /* info, warn, failure, fatal */
>  
>  /**
>   * struct cxl_event_state - Event log driver state
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index c6042db0653d..2ba059d313c2 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -672,23 +672,34 @@ static int cxl_event_get_int_policy(struct cxl_memdev_state *mds,
>  }
>  
>  static int cxl_event_config_msgnums(struct cxl_memdev_state *mds,
> -				    struct cxl_event_interrupt_policy *policy)
> +				    struct cxl_event_interrupt_policy *policy,
> +				    bool native_cxl)
>  {
>  	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
> +	size_t size_in = CXL_EVENT_INT_POLICY_BASE_SIZE;
>  	struct cxl_mbox_cmd mbox_cmd;
>  	int rc;
>  
> -	*policy = (struct cxl_event_interrupt_policy) {
> -		.info_settings = CXL_INT_MSI_MSIX,
> -		.warn_settings = CXL_INT_MSI_MSIX,
> -		.failure_settings = CXL_INT_MSI_MSIX,
> -		.fatal_settings = CXL_INT_MSI_MSIX,
> -	};
> +	/* memory event policy is left if FW has control */
> +	if (native_cxl) {
> +		*policy = (struct cxl_event_interrupt_policy) {
> +			.info_settings = CXL_INT_MSI_MSIX,
> +			.warn_settings = CXL_INT_MSI_MSIX,
> +			.failure_settings = CXL_INT_MSI_MSIX,
> +			.fatal_settings = CXL_INT_MSI_MSIX,
> +			.dcd_settings = 0,
> +		};
> +	}
> +
> +	if (cxl_dcd_supported(mds)) {
> +		policy->dcd_settings = CXL_INT_MSI_MSIX;
> +		size_in += sizeof(policy->dcd_settings);
> +	}
>  
>  	mbox_cmd = (struct cxl_mbox_cmd) {
>  		.opcode = CXL_MBOX_OP_SET_EVT_INT_POLICY,
>  		.payload_in = policy,
> -		.size_in = sizeof(*policy),
> +		.size_in = size_in,
>  	};
>  
>  	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
> @@ -735,6 +746,31 @@ static int cxl_event_irqsetup(struct cxl_memdev_state *mds,
>  	return 0;
>  }
>  
> +static int cxl_irqsetup(struct cxl_memdev_state *mds,
> +			struct cxl_event_interrupt_policy *policy,
> +			bool native_cxl)
> +{
> +	struct cxl_dev_state *cxlds = &mds->cxlds;
> +	int rc;
> +
> +	if (native_cxl) {
> +		rc = cxl_event_irqsetup(mds, policy);
> +		if (rc)
> +			return rc;
> +	}
> +
> +	if (cxl_dcd_supported(mds)) {
> +		rc = cxl_event_req_irq(cxlds, policy->dcd_settings);
> +		if (rc) {
> +			dev_err(cxlds->dev, "Failed to get interrupt for DCD event log\n");
> +			cxl_disable_dcd(mds);
> +			return rc;

If the device has both static and dynamic capacity, return an error code
here will cause cxl_event_config() return early, and
cxl_mem_get_event_records() will not be called, will it be an issue?

Fan

> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static bool cxl_event_int_is_fw(u8 setting)
>  {
>  	u8 mode = FIELD_GET(CXLDEV_EVENT_INT_MODE_MASK, setting);
> @@ -761,17 +797,25 @@ static int cxl_event_config(struct pci_host_bridge *host_bridge,
>  			    struct cxl_memdev_state *mds, bool irq_avail)
>  {
>  	struct cxl_event_interrupt_policy policy = { 0 };
> +	bool native_cxl = host_bridge->native_cxl_error;
>  	int rc;
>  
>  	/*
>  	 * When BIOS maintains CXL error reporting control, it will process
>  	 * event records.  Only one agent can do so.
> +	 *
> +	 * If BIOS has control of events and DCD is not supported skip event
> +	 * configuration.
>  	 */
> -	if (!host_bridge->native_cxl_error)
> +	if (!native_cxl && !cxl_dcd_supported(mds))
>  		return 0;
>  
>  	if (!irq_avail) {
>  		dev_info(mds->cxlds.dev, "No interrupt support, disable event processing.\n");
> +		if (cxl_dcd_supported(mds)) {
> +			dev_info(mds->cxlds.dev, "DCD requires interrupts, disable DCD\n");
> +			cxl_disable_dcd(mds);
> +		}
>  		return 0;
>  	}
>  
> @@ -779,10 +823,10 @@ static int cxl_event_config(struct pci_host_bridge *host_bridge,
>  	if (rc)
>  		return rc;
>  
> -	if (!cxl_event_validate_mem_policy(mds, &policy))
> +	if (native_cxl && !cxl_event_validate_mem_policy(mds, &policy))
>  		return -EBUSY;
>  
> -	rc = cxl_event_config_msgnums(mds, &policy);
> +	rc = cxl_event_config_msgnums(mds, &policy, native_cxl);
>  	if (rc)
>  		return rc;
>  
> @@ -790,12 +834,16 @@ static int cxl_event_config(struct pci_host_bridge *host_bridge,
>  	if (rc)
>  		return rc;
>  
> -	rc = cxl_event_irqsetup(mds, &policy);
> +	rc = cxl_irqsetup(mds, &policy, native_cxl);
>  	if (rc)
>  		return rc;
>  
>  	cxl_mem_get_event_records(mds, CXLDEV_EVENT_STATUS_ALL);
>  
> +	dev_dbg(mds->cxlds.dev, "Event config : %s DCD %s\n",
> +		native_cxl ? "OS" : "BIOS",
> +		cxl_dcd_supported(mds) ? "supported" : "not supported");
> +
>  	return 0;
>  }
>  
> 
> -- 
> 2.46.0
>
Ira Weiny Oct. 24, 2024, 3:09 a.m. UTC | #3
Fan Ni wrote:
> On Mon, Oct 07, 2024 at 06:16:25PM -0500, ira.weiny@intel.com wrote:
> > From: Navneet Singh <navneet.singh@intel.com>
> > 

[snip]

> >  
> > +static int cxl_irqsetup(struct cxl_memdev_state *mds,
> > +			struct cxl_event_interrupt_policy *policy,
> > +			bool native_cxl)
> > +{
> > +	struct cxl_dev_state *cxlds = &mds->cxlds;
> > +	int rc;
> > +
> > +	if (native_cxl) {
> > +		rc = cxl_event_irqsetup(mds, policy);
> > +		if (rc)
> > +			return rc;
> > +	}
> > +
> > +	if (cxl_dcd_supported(mds)) {
> > +		rc = cxl_event_req_irq(cxlds, policy->dcd_settings);
> > +		if (rc) {
> > +			dev_err(cxlds->dev, "Failed to get interrupt for DCD event log\n");
> > +			cxl_disable_dcd(mds);
> > +			return rc;
> 
> If the device has both static and dynamic capacity, return an error code
> here will cause cxl_event_config() return early, and
> cxl_mem_get_event_records() will not be called, will it be an issue?

Good catch as it was not my intent to fail the device probe.  Rather to
disable DCD.  In practice however, the device would be broken because it
should not be advertising DCD support without allowing for the proper irq
setup.

Current support will fail the probe if event configuration fails.  So the
error here is probably bothering to try to disable future DCD processing.

At this point I'm not sure which way to go...

Ira
diff mbox series

Patch

diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index c3b889a586d8..2d2a1884a174 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -226,7 +226,9 @@  struct cxl_event_interrupt_policy {
 	u8 warn_settings;
 	u8 failure_settings;
 	u8 fatal_settings;
+	u8 dcd_settings;
 } __packed;
+#define CXL_EVENT_INT_POLICY_BASE_SIZE 4 /* info, warn, failure, fatal */
 
 /**
  * struct cxl_event_state - Event log driver state
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index c6042db0653d..2ba059d313c2 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -672,23 +672,34 @@  static int cxl_event_get_int_policy(struct cxl_memdev_state *mds,
 }
 
 static int cxl_event_config_msgnums(struct cxl_memdev_state *mds,
-				    struct cxl_event_interrupt_policy *policy)
+				    struct cxl_event_interrupt_policy *policy,
+				    bool native_cxl)
 {
 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+	size_t size_in = CXL_EVENT_INT_POLICY_BASE_SIZE;
 	struct cxl_mbox_cmd mbox_cmd;
 	int rc;
 
-	*policy = (struct cxl_event_interrupt_policy) {
-		.info_settings = CXL_INT_MSI_MSIX,
-		.warn_settings = CXL_INT_MSI_MSIX,
-		.failure_settings = CXL_INT_MSI_MSIX,
-		.fatal_settings = CXL_INT_MSI_MSIX,
-	};
+	/* memory event policy is left if FW has control */
+	if (native_cxl) {
+		*policy = (struct cxl_event_interrupt_policy) {
+			.info_settings = CXL_INT_MSI_MSIX,
+			.warn_settings = CXL_INT_MSI_MSIX,
+			.failure_settings = CXL_INT_MSI_MSIX,
+			.fatal_settings = CXL_INT_MSI_MSIX,
+			.dcd_settings = 0,
+		};
+	}
+
+	if (cxl_dcd_supported(mds)) {
+		policy->dcd_settings = CXL_INT_MSI_MSIX;
+		size_in += sizeof(policy->dcd_settings);
+	}
 
 	mbox_cmd = (struct cxl_mbox_cmd) {
 		.opcode = CXL_MBOX_OP_SET_EVT_INT_POLICY,
 		.payload_in = policy,
-		.size_in = sizeof(*policy),
+		.size_in = size_in,
 	};
 
 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
@@ -735,6 +746,31 @@  static int cxl_event_irqsetup(struct cxl_memdev_state *mds,
 	return 0;
 }
 
+static int cxl_irqsetup(struct cxl_memdev_state *mds,
+			struct cxl_event_interrupt_policy *policy,
+			bool native_cxl)
+{
+	struct cxl_dev_state *cxlds = &mds->cxlds;
+	int rc;
+
+	if (native_cxl) {
+		rc = cxl_event_irqsetup(mds, policy);
+		if (rc)
+			return rc;
+	}
+
+	if (cxl_dcd_supported(mds)) {
+		rc = cxl_event_req_irq(cxlds, policy->dcd_settings);
+		if (rc) {
+			dev_err(cxlds->dev, "Failed to get interrupt for DCD event log\n");
+			cxl_disable_dcd(mds);
+			return rc;
+		}
+	}
+
+	return 0;
+}
+
 static bool cxl_event_int_is_fw(u8 setting)
 {
 	u8 mode = FIELD_GET(CXLDEV_EVENT_INT_MODE_MASK, setting);
@@ -761,17 +797,25 @@  static int cxl_event_config(struct pci_host_bridge *host_bridge,
 			    struct cxl_memdev_state *mds, bool irq_avail)
 {
 	struct cxl_event_interrupt_policy policy = { 0 };
+	bool native_cxl = host_bridge->native_cxl_error;
 	int rc;
 
 	/*
 	 * When BIOS maintains CXL error reporting control, it will process
 	 * event records.  Only one agent can do so.
+	 *
+	 * If BIOS has control of events and DCD is not supported skip event
+	 * configuration.
 	 */
-	if (!host_bridge->native_cxl_error)
+	if (!native_cxl && !cxl_dcd_supported(mds))
 		return 0;
 
 	if (!irq_avail) {
 		dev_info(mds->cxlds.dev, "No interrupt support, disable event processing.\n");
+		if (cxl_dcd_supported(mds)) {
+			dev_info(mds->cxlds.dev, "DCD requires interrupts, disable DCD\n");
+			cxl_disable_dcd(mds);
+		}
 		return 0;
 	}
 
@@ -779,10 +823,10 @@  static int cxl_event_config(struct pci_host_bridge *host_bridge,
 	if (rc)
 		return rc;
 
-	if (!cxl_event_validate_mem_policy(mds, &policy))
+	if (native_cxl && !cxl_event_validate_mem_policy(mds, &policy))
 		return -EBUSY;
 
-	rc = cxl_event_config_msgnums(mds, &policy);
+	rc = cxl_event_config_msgnums(mds, &policy, native_cxl);
 	if (rc)
 		return rc;
 
@@ -790,12 +834,16 @@  static int cxl_event_config(struct pci_host_bridge *host_bridge,
 	if (rc)
 		return rc;
 
-	rc = cxl_event_irqsetup(mds, &policy);
+	rc = cxl_irqsetup(mds, &policy, native_cxl);
 	if (rc)
 		return rc;
 
 	cxl_mem_get_event_records(mds, CXLDEV_EVENT_STATUS_ALL);
 
+	dev_dbg(mds->cxlds.dev, "Event config : %s DCD %s\n",
+		native_cxl ? "OS" : "BIOS",
+		cxl_dcd_supported(mds) ? "supported" : "not supported");
+
 	return 0;
 }