cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

intel_gt_sysfs.c (2741B)

      1// SPDX-License-Identifier: MIT
      2/*
      3 * Copyright © 2022 Intel Corporation
      4 */
      5
      6#include <drm/drm_device.h>
      7#include <linux/device.h>
      8#include <linux/kobject.h>
      9#include <linux/printk.h>
     10#include <linux/sysfs.h>
     11
     12#include "i915_drv.h"
     13#include "i915_sysfs.h"
     14#include "intel_gt.h"
     15#include "intel_gt_sysfs.h"
     16#include "intel_gt_sysfs_pm.h"
     17#include "intel_gt_types.h"
     18#include "intel_rc6.h"
     19
     20bool is_object_gt(struct kobject *kobj)
     21{
     22	return !strncmp(kobj->name, "gt", 2);
     23}
     24
     25static struct intel_gt *kobj_to_gt(struct kobject *kobj)
     26{
     27	return container_of(kobj, struct intel_gt, sysfs_gt);
     28}
     29
     30struct intel_gt *intel_gt_sysfs_get_drvdata(struct device *dev,
     31					    const char *name)
     32{
     33	struct kobject *kobj = &dev->kobj;
     34
     35	/*
     36	 * We are interested at knowing from where the interface
     37	 * has been called, whether it's called from gt/ or from
     38	 * the parent directory.
     39	 * From the interface position it depends also the value of
     40	 * the private data.
     41	 * If the interface is called from gt/ then private data is
     42	 * of the "struct intel_gt *" type, otherwise it's * a
     43	 * "struct drm_i915_private *" type.
     44	 */
     45	if (!is_object_gt(kobj)) {
     46		struct drm_i915_private *i915 = kdev_minor_to_i915(dev);
     47
     48		return to_gt(i915);
     49	}
     50
     51	return kobj_to_gt(kobj);
     52}
     53
     54static struct kobject *gt_get_parent_obj(struct intel_gt *gt)
     55{
     56	return &gt->i915->drm.primary->kdev->kobj;
     57}
     58
     59static ssize_t id_show(struct device *dev,
     60		       struct device_attribute *attr,
     61		       char *buf)
     62{
     63	struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name);
     64
     65	return sysfs_emit(buf, "%u\n", gt->info.id);
     66}
     67static DEVICE_ATTR_RO(id);
     68
     69static struct attribute *id_attrs[] = {
     70	&dev_attr_id.attr,
     71	NULL,
     72};
     73ATTRIBUTE_GROUPS(id);
     74
     75/* A kobject needs a release() method even if it does nothing */
     76static void kobj_gt_release(struct kobject *kobj)
     77{
     78}
     79
     80static struct kobj_type kobj_gt_type = {
     81	.release = kobj_gt_release,
     82	.sysfs_ops = &kobj_sysfs_ops,
     83	.default_groups = id_groups,
     84};
     85
     86void intel_gt_sysfs_register(struct intel_gt *gt)
     87{
     88	/*
     89	 * We need to make things right with the
     90	 * ABI compatibility. The files were originally
     91	 * generated under the parent directory.
     92	 *
     93	 * We generate the files only for gt 0
     94	 * to avoid duplicates.
     95	 */
     96	if (gt_is_root(gt))
     97		intel_gt_sysfs_pm_init(gt, gt_get_parent_obj(gt));
     98
     99	/* init and xfer ownership to sysfs tree */
    100	if (kobject_init_and_add(&gt->sysfs_gt, &kobj_gt_type,
    101				 gt->i915->sysfs_gt, "gt%d", gt->info.id))
    102		goto exit_fail;
    103
    104	intel_gt_sysfs_pm_init(gt, &gt->sysfs_gt);
    105
    106	return;
    107
    108exit_fail:
    109	kobject_put(&gt->sysfs_gt);
    110	drm_warn(&gt->i915->drm,
    111		 "failed to initialize gt%d sysfs root\n", gt->info.id);
    112}
    113
    114void intel_gt_sysfs_unregister(struct intel_gt *gt)
    115{
    116	kobject_put(&gt->sysfs_gt);
    117}