1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * AMD Platform Management Framework Util Layer
4 *
5 * Copyright (c) 2026, Advanced Micro Devices, Inc.
6 * All Rights Reserved.
7 *
8 * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
9 * Sanket Goswami <Sanket.Goswami@amd.com>
10 */
11
12 #include <linux/amd-pmf.h>
13 #include <linux/minmax.h>
14 #include <linux/miscdevice.h>
15 #include <linux/mutex.h>
16 #include <linux/uaccess.h>
17
18 #include "pmf.h"
19
20 static struct amd_pmf_dev *pmf_dev_handle;
21 static DEFINE_MUTEX(pmf_util_lock);
22
amd_pmf_populate_data(struct amd_pmf_dev * pdev,struct amd_pmf_info * info)23 static int amd_pmf_populate_data(struct amd_pmf_dev *pdev, struct amd_pmf_info *info)
24 {
25 struct ta_pmf_shared_memory *ta_sm = NULL;
26 struct ta_pmf_enact_table *in = NULL;
27 int idx;
28
29 if (!pdev || !info)
30 return -EINVAL;
31
32 if (!pdev->shbuf)
33 return -EINVAL;
34
35 ta_sm = pdev->shbuf;
36 in = &ta_sm->pmf_input.enact_table;
37
38 /* Set size */
39 info->size = sizeof(*info);
40
41 /* PMF Feature support flags */
42 if (is_apmf_func_supported(pdev, APMF_FUNC_AUTO_MODE))
43 info->features_supported |= AMD_PMF_FEAT_AUTO_MODE;
44 if (is_apmf_func_supported(pdev, APMF_FUNC_STATIC_SLIDER_GRANULAR))
45 info->features_supported |= AMD_PMF_FEAT_STATIC_POWER_SLIDER;
46 if (pdev->smart_pc_enabled)
47 info->features_supported |= AMD_PMF_FEAT_POLICY_BUILDER;
48 if (is_apmf_func_supported(pdev, APMF_FUNC_DYN_SLIDER_AC))
49 info->features_supported |= AMD_PMF_FEAT_DYNAMIC_POWER_SLIDER_AC;
50 if (is_apmf_func_supported(pdev, APMF_FUNC_DYN_SLIDER_DC))
51 info->features_supported |= AMD_PMF_FEAT_DYNAMIC_POWER_SLIDER_DC;
52
53 /* Device States */
54 info->platform_type = in->ev_info.platform_type;
55 info->laptop_placement = in->ev_info.device_state;
56 info->lid_state = in->ev_info.lid_state;
57 info->user_presence = in->ev_info.user_present;
58 info->slider_position = in->ev_info.power_slider;
59
60 /* Thermal and Power Metrics */
61 info->power_source = in->ev_info.power_source;
62 info->skin_temp = in->ev_info.skin_temperature;
63 info->gfx_busy = in->ev_info.gfx_busy;
64 info->ambient_light = in->ev_info.ambient_light;
65 info->avg_c0_residency = in->ev_info.avg_c0residency;
66 info->max_c0_residency = in->ev_info.max_c0residency;
67 info->socket_power = in->ev_info.socket_power;
68
69 /* Custom BIOS input parameters */
70 for (idx = 0; idx < AMD_PMF_BIOS_PARAMS_MAX; idx++)
71 info->bios_input[idx] = amd_pmf_get_ta_custom_bios_inputs(in, idx);
72
73 /* BIOS output parameters */
74 for (idx = 0; idx < AMD_PMF_BIOS_PARAMS_MAX; idx++)
75 info->bios_output[idx] = pdev->bios_output[idx];
76
77 return 0;
78 }
79
amd_pmf_set_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)80 static long amd_pmf_set_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
81 {
82 struct amd_pmf_dev *pdev = filp->private_data;
83 void __user *argp = (void __user *)arg;
84 struct amd_pmf_info info = {};
85 size_t copy_size;
86 __u64 user_size;
87 int ret;
88
89 if (cmd != IOCTL_AMD_PMF_POPULATE_DATA)
90 return -ENOTTY;
91
92 /* First read just the size field from userspace */
93 if (copy_from_user(&user_size, argp, sizeof(user_size)))
94 return -EFAULT;
95
96 guard(mutex)(&pmf_util_lock);
97 ret = amd_pmf_populate_data(pdev, &info);
98 if (ret)
99 return ret;
100
101 copy_size = min_t(size_t, user_size, sizeof(info));
102
103 /* Set actual size being copied */
104 info.size = copy_size;
105
106 if (copy_to_user(argp, &info, copy_size))
107 return -EFAULT;
108
109 return 0;
110 }
111
amd_pmf_open(struct inode * inode,struct file * filp)112 static int amd_pmf_open(struct inode *inode, struct file *filp)
113 {
114 guard(mutex)(&pmf_util_lock);
115 if (!pmf_dev_handle)
116 return -ENODEV;
117
118 filp->private_data = pmf_dev_handle;
119 return 0;
120 }
121
122 static const struct file_operations pmf_if_ops = {
123 .owner = THIS_MODULE,
124 .open = amd_pmf_open,
125 .unlocked_ioctl = amd_pmf_set_ioctl,
126 };
127
128 static struct miscdevice amd_pmf_util_if = {
129 .minor = MISC_DYNAMIC_MINOR,
130 .name = "amdpmf_interface",
131 .fops = &pmf_if_ops,
132 };
133
amd_pmf_cdev_register(struct amd_pmf_dev * dev)134 int amd_pmf_cdev_register(struct amd_pmf_dev *dev)
135 {
136 int ret;
137
138 guard(mutex)(&pmf_util_lock);
139 pmf_dev_handle = dev;
140 ret = misc_register(&amd_pmf_util_if);
141 if (ret)
142 pmf_dev_handle = NULL;
143
144 return ret;
145 }
146
amd_pmf_cdev_unregister(void)147 void amd_pmf_cdev_unregister(void)
148 {
149 guard(mutex)(&pmf_util_lock);
150 if (pmf_dev_handle)
151 misc_deregister(&amd_pmf_util_if);
152 pmf_dev_handle = NULL;
153 }
154