Commit 199cf8c3 authored by Vishal Verma's avatar Vishal Verma Committed by Dan Williams
Browse files

cxl/pci.c: Add a 'label_storage_size' attribute to the memdev 



The 'Identify Device' mailbox command returns an 'lsa_size', which is
the size of the label storage area on the device. Export it as a sysfs
attribute so that userspace tooling to read/write the LSA can determine
the size without having to run an 'Identify Device' on their own.

Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarVishal Verma <vishal.l.verma@intel.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210520194745.1095517-1-vishal.l.verma@intel.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 21e9f767

drivers/cxl/mem.h

+3 −0
Original line number Diff line number Diff line
@@ -54,6 +54,8 @@ struct cxl_memdev { 
 * @regs: Parsed register blocks

 * @payload_size: Size of space for payload

 *                (CXL 2.0 8.2.8.4.3 Mailbox Capabilities Register)

 * @lsa_size: Size of Label Storage Area

 *                (CXL 2.0 8.2.9.5.1.1 Identify Memory Device)

 * @mbox_mutex: Mutex to synchronize mailbox access.

 * @firmware_version: Firmware version for the memory device.

 * @enabled_cmds: Hardware commands found enabled in CEL.
@@ -68,6 +70,7 @@ struct cxl_mem { 
	struct cxl_regs regs;



	size_t payload_size;

	size_t lsa_size;

	struct mutex mbox_mutex; /* Protects device mailbox and firmware */

	char firmware_version[0x10];

	unsigned long *enabled_cmds;

drivers/cxl/pci.c

+12 −0
Original line number Diff line number Diff line
@@ -1036,6 +1036,16 @@ static ssize_t payload_max_show(struct device *dev, 
}

static DEVICE_ATTR_RO(payload_max);



static ssize_t label_storage_size_show(struct device *dev,

				struct device_attribute *attr, char *buf)

{

	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);

	struct cxl_mem *cxlm = cxlmd->cxlm;



	return sysfs_emit(buf, "%zu\n", cxlm->lsa_size);

}

static DEVICE_ATTR_RO(label_storage_size);



static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,

			     char *buf)

{
@@ -1065,6 +1075,7 @@ static struct device_attribute dev_attr_pmem_size = 
static struct attribute *cxl_memdev_attributes[] = {

	&dev_attr_firmware_version.attr,

	&dev_attr_payload_max.attr,

	&dev_attr_label_storage_size.attr,

	NULL,

};
@@ -1397,6 +1408,7 @@ static int cxl_mem_identify(struct cxl_mem *cxlm) 
	cxlm->pmem_range.end =

		le64_to_cpu(id.persistent_capacity) * SZ_256M - 1;



	cxlm->lsa_size = le32_to_cpu(id.lsa_size);

	memcpy(cxlm->firmware_version, id.fw_revision, sizeof(id.fw_revision));



	return 0;