diff mbox series

[4/4] cxl: Add callback to parse the DSMAS subtables from CDAT

Message ID 168330799471.2042604.1887260521284311424.stgit@djiang5-mobl3 (mailing list archive)
State Handled Elsewhere, archived
Headers show
Series acpi: Add CDAT parsing support to ACPI tables code | expand

Commit Message

Dave Jiang May 5, 2023, 5:33 p.m. UTC 
Provide a callback function to the CDAT parser in order to parse the Device
Scoped Memory Affinity Structure (DSMAS). Each DSMAS structure contains the
DPA range and its associated attributes in each entry. See the CDAT
specification for details. The device handle and the DPA range is saved and
to be associated with the DSLBIS locality data when the DSLBIS entries are
parsed. The list is a local list. When the total path performance data is
calculated and storred this list can be discarded.

Coherent Device Attribute Table 1.03 2.1 Device Scoped memory Affinity
Structure (DSMAS)

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
v5:
- Update commit log to indicate what list is used for. (Jonathan, Dan)
- Use acpi_table_parse_cdat()
- Isolate cdat code behind CONFIG_ACPI
v3:
- Add spec section number. (Alison)
- Remove cast from void *. (Alison)
- Refactor cxl_port_probe() block. (Alison)
- Move CDAT parse to cxl_endpoint_port_probe()

v2:
- Add DSMAS table size check. (Lukas)
- Use local DSMAS header for LE handling.
- Remove dsmas lock. (Jonathan)
- Fix handle size (Jonathan)
- Add LE to host conversion for DSMAS address and length.
- Make dsmas_list local
---
 drivers/cxl/core/Makefile |    1 +
 drivers/cxl/core/cdat.c   |   40 ++++++++++++++++++++++++++++++++++++++++
 drivers/cxl/cxl.h         |   18 ++++++++++++++++++
 drivers/cxl/port.c        |   22 ++++++++++++++++++++++
 4 files changed, 81 insertions(+)
 create mode 100644 drivers/cxl/core/cdat.c

Comments

Jonathan Cameron May 12, 2023, 2:25 p.m. UTC | #1 
On Fri, 05 May 2023 10:33:14 -0700
Dave Jiang <dave.jiang@intel.com> wrote:

> Provide a callback function to the CDAT parser in order to parse the Device
> Scoped Memory Affinity Structure (DSMAS). Each DSMAS structure contains the
> DPA range and its associated attributes in each entry. See the CDAT
> specification for details. The device handle and the DPA range is saved and
> to be associated with the DSLBIS locality data when the DSLBIS entries are
> parsed. The list is a local list. When the total path performance data is
> calculated and storred this list can be discarded.
> 
> Coherent Device Attribute Table 1.03 2.1 Device Scoped memory Affinity
> Structure (DSMAS)
> 
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>
A few trivials inline.

I've pretty much forgotten this since I last looked, so it's more than
possible I disagree with what I may have said for previous versions.

Jonathan

> ---
> v5:
> - Update commit log to indicate what list is used for. (Jonathan, Dan)
> - Use acpi_table_parse_cdat()
> - Isolate cdat code behind CONFIG_ACPI
> v3:
> - Add spec section number. (Alison)
> - Remove cast from void *. (Alison)
> - Refactor cxl_port_probe() block. (Alison)
> - Move CDAT parse to cxl_endpoint_port_probe()
> 
> v2:
> - Add DSMAS table size check. (Lukas)
> - Use local DSMAS header for LE handling.
> - Remove dsmas lock. (Jonathan)
> - Fix handle size (Jonathan)
> - Add LE to host conversion for DSMAS address and length.
> - Make dsmas_list local
> ---
>  drivers/cxl/core/Makefile |    1 +
>  drivers/cxl/core/cdat.c   |   40 ++++++++++++++++++++++++++++++++++++++++
>  drivers/cxl/cxl.h         |   18 ++++++++++++++++++
>  drivers/cxl/port.c        |   22 ++++++++++++++++++++++
>  4 files changed, 81 insertions(+)
>  create mode 100644 drivers/cxl/core/cdat.c
> 
> diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
> index ca4ae31d8f57..98ddfd110f9b 100644
> --- a/drivers/cxl/core/Makefile
> +++ b/drivers/cxl/core/Makefile
> @@ -12,5 +12,6 @@ cxl_core-y += memdev.o
>  cxl_core-y += mbox.o
>  cxl_core-y += pci.o
>  cxl_core-y += hdm.o
> +cxl_core-$(CONFIG_ACPI) += cdat.o
>  cxl_core-$(CONFIG_TRACING) += trace.o
>  cxl_core-$(CONFIG_CXL_REGION) += region.o
> diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
> new file mode 100644
> index 000000000000..61979f0789aa
> --- /dev/null
> +++ b/drivers/cxl/core/cdat.c
> @@ -0,0 +1,40 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/* Copyright(c) 2023 Intel Corporation. All rights reserved. */
> +#include <linux/acpi.h>
> +#include "cxlpci.h"
> +#include "cxl.h"
> +
> +static int cdat_dsmas_handler(union acpi_subtable_headers *header, void *arg,
> +			      const unsigned long end)
> +{
> +	struct acpi_cdat_dsmas *dsmas = (struct acpi_cdat_dsmas *)header;

No functional change, but I'd rather see the &header->cdat 
cast than the union.  Makes it more obvious why this is fine.

> +	struct list_head *dsmas_list = arg;
> +	struct dsmas_entry *dent;
> +	u16 len;
> +
> +	len = le16_to_cpu((__force __le16)dsmas->header.length);
> +	if (len != sizeof(*dsmas) || (unsigned long)header + len > end) {
> +		pr_warn("Malformed DSMAS table length: (%lu:%u)\n",
> +			(unsigned long)sizeof(*dsmas), len);
> +		return -EINVAL;
> +	}
> +
> +	dent = kzalloc(sizeof(*dent), GFP_KERNEL);
> +	if (!dent)
> +		return -ENOMEM;
> +
> +	dent->handle = dsmas->dsmad_handle;
> +	dent->dpa_range.start = le64_to_cpu((__force __le64)dsmas->dpa_base_address);
> +	dent->dpa_range.end = le64_to_cpu((__force __le64)dsmas->dpa_base_address) +
> +			      le64_to_cpu((__force __le64)dsmas->dpa_length) - 1;
> +	list_add_tail(&dent->list, dsmas_list);
> +
> +	return 0;
> +}
> +
> +int cxl_cdat_endpoint_process(struct cxl_port *port, struct list_head *list)
> +{
> +	return acpi_table_parse_cdat(ACPI_CDAT_TYPE_DSMAS, cdat_dsmas_handler,
> +				     list, port->cdat.table);
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_cdat_endpoint_process, CXL);
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 4577d808ac6d..dda7238b47f5 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -7,6 +7,7 @@
>  #include <linux/libnvdimm.h>
>  #include <linux/bitfield.h>
>  #include <linux/bitops.h>
> +#include <linux/list.h>
>  #include <linux/log2.h>
>  #include <linux/io.h>
>  
> @@ -791,6 +792,23 @@ static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
>  }
>  #endif
>  
> +/* CDAT related bits */
> +struct dsmas_entry {
> +	struct list_head list;
> +	struct range dpa_range;
> +	u8 handle;
> +};
> +
> +#ifdef CONFIG_ACPI
> +int cxl_cdat_endpoint_process(struct cxl_port *port, struct list_head *list);
> +#else
> +static inline int cxl_cdat_endpoint_process(struct cxl_port *port,
> +					    struct list_head *list)
> +{
> +	return -EOPNOTSUPP;
> +}
> +#endif
> +
>  /*
>   * Unit test builds overrides this to __weak, find the 'strong' version
>   * of these symbols in tools/testing/cxl/.
> diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
> index a49f5eb149f1..da023feaa6e2 100644
> --- a/drivers/cxl/port.c
> +++ b/drivers/cxl/port.c
> @@ -57,6 +57,16 @@ static int discover_region(struct device *dev, void *root)
>  	return 0;
>  }
>  
> +static void dsmas_list_destroy(struct list_head *dsmas_list)
> +{
> +	struct dsmas_entry *dentry, *n;
> +
> +	list_for_each_entry_safe(dentry, n, dsmas_list, list) {
> +		list_del(&dentry->list);
> +		kfree(dentry);
> +	}
> +}

I'd rather see this alongside the code that created it in core/cdat.c
than in here.

> +
>  static int cxl_switch_port_probe(struct cxl_port *port)
>  {
>  	struct cxl_hdm *cxlhdm;
> @@ -131,6 +141,18 @@ static int cxl_endpoint_port_probe(struct cxl_port *port)
>  	device_for_each_child(&port->dev, root, discover_region);
>  	put_device(&root->dev);
>  
> +	if (port->cdat.table) {
> +		LIST_HEAD(dsmas_list);
> +
> +		rc = cxl_cdat_endpoint_process(port, &dsmas_list);
> +		if (rc < 0)
> +			dev_dbg(&port->dev, "Failed to parse CDAT: %d\n", rc);
> +
> +		/* Performance data processing */
> +
> +		dsmas_list_destroy(&dsmas_list);
> +	}
> +
>  	return 0;
>  }
>  
> 
> 
>
diff mbox series

Patch

diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
index ca4ae31d8f57..98ddfd110f9b 100644
--- a/drivers/cxl/core/Makefile
+++ b/drivers/cxl/core/Makefile
@@ -12,5 +12,6 @@  cxl_core-y += memdev.o
 cxl_core-y += mbox.o
 cxl_core-y += pci.o
 cxl_core-y += hdm.o
+cxl_core-$(CONFIG_ACPI) += cdat.o
 cxl_core-$(CONFIG_TRACING) += trace.o
 cxl_core-$(CONFIG_CXL_REGION) += region.o
diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c
new file mode 100644
index 000000000000..61979f0789aa
--- /dev/null
+++ b/drivers/cxl/core/cdat.c
@@ -0,0 +1,40 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2023 Intel Corporation. All rights reserved. */
+#include <linux/acpi.h>
+#include "cxlpci.h"
+#include "cxl.h"
+
+static int cdat_dsmas_handler(union acpi_subtable_headers *header, void *arg,
+			      const unsigned long end)
+{
+	struct acpi_cdat_dsmas *dsmas = (struct acpi_cdat_dsmas *)header;
+	struct list_head *dsmas_list = arg;
+	struct dsmas_entry *dent;
+	u16 len;
+
+	len = le16_to_cpu((__force __le16)dsmas->header.length);
+	if (len != sizeof(*dsmas) || (unsigned long)header + len > end) {
+		pr_warn("Malformed DSMAS table length: (%lu:%u)\n",
+			(unsigned long)sizeof(*dsmas), len);
+		return -EINVAL;
+	}
+
+	dent = kzalloc(sizeof(*dent), GFP_KERNEL);
+	if (!dent)
+		return -ENOMEM;
+
+	dent->handle = dsmas->dsmad_handle;
+	dent->dpa_range.start = le64_to_cpu((__force __le64)dsmas->dpa_base_address);
+	dent->dpa_range.end = le64_to_cpu((__force __le64)dsmas->dpa_base_address) +
+			      le64_to_cpu((__force __le64)dsmas->dpa_length) - 1;
+	list_add_tail(&dent->list, dsmas_list);
+
+	return 0;
+}
+
+int cxl_cdat_endpoint_process(struct cxl_port *port, struct list_head *list)
+{
+	return acpi_table_parse_cdat(ACPI_CDAT_TYPE_DSMAS, cdat_dsmas_handler,
+				     list, port->cdat.table);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_cdat_endpoint_process, CXL);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 4577d808ac6d..dda7238b47f5 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -7,6 +7,7 @@ 
 #include <linux/libnvdimm.h>
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
+#include <linux/list.h>
 #include <linux/log2.h>
 #include <linux/io.h>
 
@@ -791,6 +792,23 @@  static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
 }
 #endif
 
+/* CDAT related bits */
+struct dsmas_entry {
+	struct list_head list;
+	struct range dpa_range;
+	u8 handle;
+};
+
+#ifdef CONFIG_ACPI
+int cxl_cdat_endpoint_process(struct cxl_port *port, struct list_head *list);
+#else
+static inline int cxl_cdat_endpoint_process(struct cxl_port *port,
+					    struct list_head *list)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
 /*
  * Unit test builds overrides this to __weak, find the 'strong' version
  * of these symbols in tools/testing/cxl/.
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index a49f5eb149f1..da023feaa6e2 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -57,6 +57,16 @@  static int discover_region(struct device *dev, void *root)
 	return 0;
 }
 
+static void dsmas_list_destroy(struct list_head *dsmas_list)
+{
+	struct dsmas_entry *dentry, *n;
+
+	list_for_each_entry_safe(dentry, n, dsmas_list, list) {
+		list_del(&dentry->list);
+		kfree(dentry);
+	}
+}
+
 static int cxl_switch_port_probe(struct cxl_port *port)
 {
 	struct cxl_hdm *cxlhdm;
@@ -131,6 +141,18 @@  static int cxl_endpoint_port_probe(struct cxl_port *port)
 	device_for_each_child(&port->dev, root, discover_region);
 	put_device(&root->dev);
 
+	if (port->cdat.table) {
+		LIST_HEAD(dsmas_list);
+
+		rc = cxl_cdat_endpoint_process(port, &dsmas_list);
+		if (rc < 0)
+			dev_dbg(&port->dev, "Failed to parse CDAT: %d\n", rc);
+
+		/* Performance data processing */
+
+		dsmas_list_destroy(&dsmas_list);
+	}
+
 	return 0;
 }