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 static 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
current_batch_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)90 static ssize_t current_batch_store(struct device *dev,
91 struct device_attribute *attr,
92 const char *buf, size_t count)
93 {
94 struct ifs_data *ifsd = ifs_get_data(dev);
95 unsigned int cur_batch;
96 int rc;
97
98 rc = kstrtouint(buf, 0, &cur_batch);
99 if (rc < 0 || cur_batch > 0xff)
100 return -EINVAL;
101
102 if (down_interruptible(&ifs_sem))
103 return -EINTR;
104
105 ifsd->cur_batch = cur_batch;
106
107 rc = ifs_load_firmware(dev);
108
109 up(&ifs_sem);
110
111 return (rc == 0) ? count : rc;
112 }
113
current_batch_show(struct device * dev,struct device_attribute * attr,char * buf)114 static ssize_t current_batch_show(struct device *dev,
115 struct device_attribute *attr, char *buf)
116 {
117 struct ifs_data *ifsd = ifs_get_data(dev);
118
119 if (!ifsd->loaded)
120 return sysfs_emit(buf, "none\n");
121 else
122 return sysfs_emit(buf, "0x%02x\n", ifsd->cur_batch);
123 }
124
125 static DEVICE_ATTR_RW(current_batch);
126
127 /*
128 * Display currently loaded IFS image version.
129 */
image_version_show(struct device * dev,struct device_attribute * attr,char * buf)130 static ssize_t image_version_show(struct device *dev,
131 struct device_attribute *attr, char *buf)
132 {
133 struct ifs_data *ifsd = ifs_get_data(dev);
134
135 if (!ifsd->loaded)
136 return sysfs_emit(buf, "%s\n", "none");
137 else
138 return sysfs_emit(buf, "%#x\n", ifsd->loaded_version);
139 }
140
141 static DEVICE_ATTR_RO(image_version);
142
143 /* global scan sysfs attributes */
144 static struct attribute *plat_ifs_attrs[] = {
145 &dev_attr_details.attr,
146 &dev_attr_status.attr,
147 &dev_attr_run_test.attr,
148 &dev_attr_current_batch.attr,
149 &dev_attr_image_version.attr,
150 NULL
151 };
152
153 ATTRIBUTE_GROUPS(plat_ifs);
154
ifs_get_groups(void)155 const struct attribute_group **ifs_get_groups(void)
156 {
157 return plat_ifs_groups;
158 }
159