path: root/drivers/cxl/core/memdev.c

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2020 Intel Corporation. */

#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/firmware.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/pci.h>
#include <cxlmem.h>
#include "trace.h"
#include "core.h"

static DECLARE_RWSEM(cxl_memdev_rwsem);

/*
 * An entire PCI topology full of devices should be enough for any
 * config
 */
#define CXL_MEM_MAX_DEVS 65536

static int cxl_mem_major;
static DEFINE_IDA(cxl_memdev_ida);

static void cxl_memdev_release(struct device *dev)
{
	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);

	ida_free(&cxl_memdev_ida, cxlmd->id);
	devm_cxl_memdev_edac_release(cxlmd);
	kfree(cxlmd);
}

static char *cxl_memdev_devnode(const struct device *dev, umode_t *mode, kuid_t *uid,
				kgid_t *gid)
{
	return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev));
}

static ssize_t firmware_version_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{
	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
	struct cxl_dev_state *cxlds = cxlmd->cxlds;
	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);

	if (!mds)
		return sysfs_emit(buf, "\n");
	return sysfs_emit(buf, "%.16s\n", mds->firmware_version);
}
static DEVICE_ATTR_RO(firmware_version);

static ssize_t payload_max_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
	struct cxl_dev_state *cxlds = cxlmd->cxlds;
	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);

	if (!mds)
		return sysfs_emit(buf, "\n");
	return sysfs_emit(buf, "%zu\n", cxlds->cxl_mbox.payload_size);
}
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_dev_state *cxlds = cxlmd->cxlds;
	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);

	if (!mds)
		return sysfs_emit(buf, "\n");
	return sysfs_emit(buf, "%zu\n", mds->lsa_size);
}
static DEVICE_ATTR_RO(label_storage_size);

static resource_size_t cxl_ram_size(struct cxl_dev_state *cxlds)
{
	/* Static RAM is only expected at partition 0. */
	if (cxlds->part[0].mode != CXL_PARTMODE_RAM)
		return 0;
	return resource_size(&cxlds->part[0].res);
}

static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{
	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
	struct cxl_dev_state *