1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2022 Intel Corporation. */
3
4 #include <linux/cpu.h>
5 #include <linux/delay.h>
6 #include <linux/fs.h>
7 #include <linux/semaphore.h>
8 #include <linux/slab.h>
9
10 #include "ifs.h"
11
12 /*
13 * Protects against simultaneous tests on multiple cores, or
14 * reloading can file while a test is in progress
15 */
16 DEFINE_SEMAPHORE(ifs_sem);
17
18 /*
19 * The sysfs interface to check additional details of last test
20 * cat /sys/devices/system/platform/ifs/details
21 */
details_show(struct device * dev,struct device_attribute * attr,char * buf)22 static ssize_t details_show(struct device *dev,
23 struct device_attribute *attr,
24 char *buf)
25 {
26 struct ifs_data *ifsd = ifs_get_data(dev);
27
28 return sysfs_emit(buf, "%#llx\n", ifsd->scan_details);
29 }
30
31 static DEVICE_ATTR_RO(details);
32
33 static const char * const status_msg[] = {
34 [SCAN_NOT_TESTED] = "untested",
35 [SCAN_TEST_PASS] = "pass",
36 [SCAN_TEST_FAIL] = "fail"
37 };
38
39 /*
40 * The sysfs interface to check the test status:
41 * To check the status of last test
42 * cat /sys/devices/platform/ifs/status
43 */
status_show(struct device * dev,struct device_attribute * attr,char * buf)44 static ssize_t status_show(struct device *dev,
45 struct device_attribute *attr,
46 char *buf)
47 {
48 struct ifs_data *ifsd = ifs_get_data(dev);
49
50 return sysfs_emit(buf, "%s\n", status_msg[ifsd->status]);
51 }
52
53 static DEVICE_ATTR_RO(status);
54
55 /*
56 * The sysfs interface for single core testing
57 * To start test, for example, cpu5
58 * echo 5 > /sys/devices/platform/ifs/run_test
59 * To check the result:
60 * cat /sys/devices/platform/ifs/result
61 * The sibling core gets tested at the same time.
62 */
run_test_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)63 static ssize_t run_test_store(struct device *dev,
64 struct device_attribute *attr,
65 const char *buf, size_t count)
66 {
67 struct ifs_data *ifsd = ifs_get_data(dev);
68 unsigned int cpu;
69 int rc;
70
71 rc = kstrtouint(buf, 0, &cpu);
72 if (rc < 0 || cpu >= nr_cpu_ids)
73 return -EINVAL;
74
75 if (down_interruptible(&ifs_sem))
76 return -EINTR;
77
78 if (!ifsd->loaded)
79 rc = -EPERM;
80 else
81 rc = do_core_test(cpu, dev);
82
83 up(&ifs_sem);
84
85 return rc ? rc : count;
86 }
87
88 static DEVICE_ATTR_WO(run_test);
89
90 /*
91 * Reload the IFS image. When user wants to install new IFS image
92 */
reload_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)93 static ssize_t reload_store(struct device *dev,
94 struct device_attribute *attr,
95 const char *buf, size_t count)
96 {
97 struct ifs_data *ifsd = ifs_get_data(dev);
98 bool res;
99
100
101 if (kstrtobool(buf, &res))
102 return -EINVAL;
103 if (!res)
104 return count;
105
106 if (down_interruptible(&ifs_sem))
107 return -EINTR;
108
109 ifs_load_firmware(dev);
110
111 up(&ifs_sem);
112
113 return ifsd->loaded ? count : -ENODEV;
114 }
115
116 static DEVICE_ATTR_WO(reload);
117
118 /*
119 * Display currently loaded IFS image version.
120 */
image_version_show(struct device * dev,struct device_attribute * attr,char * buf)121 static ssize_t image_version_show(struct device *dev,
122 struct device_attribute *attr, char *buf)
123 {
124 struct ifs_data *ifsd = ifs_get_data(dev);
125
126 if (!ifsd->loaded)
127 return sysfs_emit(buf, "%s\n", "none");
128 else
129 return sysfs_emit(buf, "%#x\n", ifsd->loaded_version);
130 }
131
132 static DEVICE_ATTR_RO(image_version);
133
134 /* global scan sysfs attributes */
135 static struct attribute *plat_ifs_attrs[] = {
136 &dev_attr_details.attr,
137 &dev_attr_status.attr,
138 &dev_attr_run_test.attr,
139 &dev_attr_reload.attr,
140 &dev_attr_image_version.attr,
141 NULL
142 };
143
144 ATTRIBUTE_GROUPS(plat_ifs);
145
ifs_get_groups(void)146 const struct attribute_group **ifs_get_groups(void)
147 {
148 return plat_ifs_groups;
149 }
150