drivers/platform/x86/intel/ifs/sysfs.c

   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, 1);
  17
  18 /*
  19  * The sysfs interface to check additional details of last test
  20  * cat /sys/devices/system/platform/ifs/details
  21  */
  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  */
  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  */
  63 static ssize_t run_test_store(struct device *dev,
  64                               struct device_attribute *attr,
  65                               const char *buf, size_t count)
  66 {
  67         unsigned int cpu;
  68         int rc;
  69
  70         rc = kstrtouint(buf, 0, &cpu);
  71         if (rc < 0 || cpu >= nr_cpu_ids)
  72                 return -EINVAL;
  73
  74         if (down_interruptible(&ifs_sem))
  75                 return -EINTR;
  76
  77         rc = do_core_test(cpu, dev);
  78
  79         up(&ifs_sem);
  80
  81         return rc ? rc : count;
  82 }
  83
  84 static DEVICE_ATTR_WO(run_test);
  85
  86 static ssize_t current_batch_store(struct device *dev,
  87                                    struct device_attribute *attr,
  88                                    const char *buf, size_t count)
  89 {
  90         struct ifs_data *ifsd = ifs_get_data(dev);
  91         unsigned int cur_batch;
  92         int rc;
  93
  94         rc = kstrtouint(buf, 0, &cur_batch);
  95         if (rc < 0 || cur_batch > 0xff)
  96                 return -EINVAL;
  97
  98         if (down_interruptible(&ifs_sem))
  99                 return -EINTR;
 100
 101         ifsd->cur_batch = cur_batch;
 102
 103         rc = ifs_load_firmware(dev);
 104
 105         up(&ifs_sem);
 106
 107         return (rc == 0) ? count : rc;
 108 }
 109
 110 static ssize_t current_batch_show(struct device *dev,
 111                                   struct device_attribute *attr, char *buf)
 112 {
 113         struct ifs_data *ifsd = ifs_get_data(dev);
 114
 115         if (!ifsd->loaded)
 116                 return sysfs_emit(buf, "none\n");
 117         else
 118                 return sysfs_emit(buf, "0x%02x\n", ifsd->cur_batch);
 119 }
 120
 121 static DEVICE_ATTR_RW(current_batch);
 122
 123 /*
 124  * Display currently loaded IFS image version.
 125  */
 126 static ssize_t image_version_show(struct device *dev,
 127                                   struct device_attribute *attr, char *buf)
 128 {
 129         struct ifs_data *ifsd = ifs_get_data(dev);
 130
 131         if (!ifsd->loaded)
 132                 return sysfs_emit(buf, "%s\n", "none");
 133         else
 134                 return sysfs_emit(buf, "%#x\n", ifsd->loaded_version);
 135 }
 136
 137 static DEVICE_ATTR_RO(image_version);
 138
 139 /* global scan sysfs attributes */
 140 struct attribute *plat_ifs_attrs[] = {
 141         &dev_attr_details.attr,
 142         &dev_attr_status.attr,
 143         &dev_attr_run_test.attr,
 144         &dev_attr_current_batch.attr,
 145         &dev_attr_image_version.attr,
 146         NULL
 147 };
 148
 149 /* global array sysfs attributes */
 150 struct attribute *plat_ifs_array_attrs[] = {
 151         &dev_attr_details.attr,
 152         &dev_attr_status.attr,
 153         &dev_attr_run_test.attr,
 154         NULL
 155 };