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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Copyright(c) 2022 Intel Corporation. */
   3
   4 #include <linux/bitfield.h>
   5 #include <linux/module.h>
   6 #include <linux/kdev_t.h>
   7 #include <linux/semaphore.h>
   8 #include <linux/slab.h>
   9
  10 #include <asm/cpu_device_id.h>
  11
  12 #include "ifs.h"
  13
  14 #define X86_MATCH(vfm, array_gen)                               \
  15         X86_MATCH_VFM_FEATURE(vfm, X86_FEATURE_CORE_CAPABILITIES, array_gen)
  16
  17 static const struct x86_cpu_id ifs_cpu_ids[] __initconst = {
  18         X86_MATCH(INTEL_SAPPHIRERAPIDS_X, ARRAY_GEN0),
  19         X86_MATCH(INTEL_EMERALDRAPIDS_X, ARRAY_GEN0),
  20         X86_MATCH(INTEL_GRANITERAPIDS_X, ARRAY_GEN0),
  21         X86_MATCH(INTEL_GRANITERAPIDS_D, ARRAY_GEN0),
  22         X86_MATCH(INTEL_ATOM_CRESTMONT_X, ARRAY_GEN1),
  23         {}
  24 };
  25 MODULE_DEVICE_TABLE(x86cpu, ifs_cpu_ids);
  26
  27 ATTRIBUTE_GROUPS(plat_ifs);
  28 ATTRIBUTE_GROUPS(plat_ifs_array);
  29
  30 bool *ifs_pkg_auth;
  31
  32 static const struct ifs_test_caps scan_test = {
  33         .integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
  34         .test_num = IFS_TYPE_SAF,
  35         .image_suffix = "scan",
  36 };
  37
  38 static const struct ifs_test_caps array_test = {
  39         .integrity_cap_bit = MSR_INTEGRITY_CAPS_ARRAY_BIST_BIT,
  40         .test_num = IFS_TYPE_ARRAY_BIST,
  41 };
  42
  43 static const struct ifs_test_msrs scan_msrs = {
  44         .copy_hashes = MSR_COPY_SCAN_HASHES,
  45         .copy_hashes_status = MSR_SCAN_HASHES_STATUS,
  46         .copy_chunks = MSR_AUTHENTICATE_AND_COPY_CHUNK,
  47         .copy_chunks_status = MSR_CHUNKS_AUTHENTICATION_STATUS,
  48         .test_ctrl = MSR_SAF_CTRL,
  49 };
  50
  51 static const struct ifs_test_msrs sbaf_msrs = {
  52         .copy_hashes = MSR_COPY_SBAF_HASHES,
  53         .copy_hashes_status = MSR_SBAF_HASHES_STATUS,
  54         .copy_chunks = MSR_AUTHENTICATE_AND_COPY_SBAF_CHUNK,
  55         .copy_chunks_status = MSR_SBAF_CHUNKS_AUTHENTICATION_STATUS,
  56         .test_ctrl = MSR_SBAF_CTRL,
  57 };
  58
  59 static const struct ifs_test_caps sbaf_test = {
  60         .integrity_cap_bit = MSR_INTEGRITY_CAPS_SBAF_BIT,
  61         .test_num = IFS_TYPE_SBAF,
  62         .image_suffix = "sbft",
  63 };
  64
  65 static struct ifs_device ifs_devices[] = {
  66         [IFS_TYPE_SAF] = {
  67                 .test_caps = &scan_test,
  68                 .test_msrs = &scan_msrs,
  69                 .misc = {
  70                         .name = "intel_ifs_0",
  71                         .minor = MISC_DYNAMIC_MINOR,
  72                         .groups = plat_ifs_groups,
  73                 },
  74         },
  75         [IFS_TYPE_ARRAY_BIST] = {
  76                 .test_caps = &array_test,
  77                 .misc = {
  78                         .name = "intel_ifs_1",
  79                         .minor = MISC_DYNAMIC_MINOR,
  80                         .groups = plat_ifs_array_groups,
  81                 },
  82         },
  83         [IFS_TYPE_SBAF] = {
  84                 .test_caps = &sbaf_test,
  85                 .test_msrs = &sbaf_msrs,
  86                 .misc = {
  87                         .name = "intel_ifs_2",
  88                         .minor = MISC_DYNAMIC_MINOR,
  89                         .groups = plat_ifs_groups,
  90                 },
  91         },
  92 };
  93
  94 #define IFS_NUMTESTS ARRAY_SIZE(ifs_devices)
  95
  96 static void ifs_cleanup(void)
  97 {
  98         int i;
  99
 100         for (i = 0; i < IFS_NUMTESTS; i++) {
 101                 if (ifs_devices[i].misc.this_device)
 102                         misc_deregister(&ifs_devices[i].misc);
 103         }
 104         kfree(ifs_pkg_auth);
 105 }
 106
 107 static int __init ifs_init(void)
 108 {
 109         const struct x86_cpu_id *m;
 110         u64 msrval;
 111         int i, ret;
 112
 113         m = x86_match_cpu(ifs_cpu_ids);
 114         if (!m)
 115                 return -ENODEV;
 116
 117         if (rdmsrl_safe(MSR_IA32_CORE_CAPS, &msrval))
 118                 return -ENODEV;
 119
 120         if (!(msrval & MSR_IA32_CORE_CAPS_INTEGRITY_CAPS))
 121                 return -ENODEV;
 122
 123         if (rdmsrl_safe(MSR_INTEGRITY_CAPS, &msrval))
 124                 return -ENODEV;
 125
 126         ifs_pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
 127         if (!ifs_pkg_auth)
 128                 return -ENOMEM;
 129
 130         for (i = 0; i < IFS_NUMTESTS; i++) {
 131                 if (!(msrval & BIT(ifs_devices[i].test_caps->integrity_cap_bit)))
 132                         continue;
 133                 ifs_devices[i].rw_data.generation = FIELD_GET(MSR_INTEGRITY_CAPS_SAF_GEN_MASK,
 134                                                               msrval);
 135                 ifs_devices[i].rw_data.array_gen = (u32)m->driver_data;
 136                 ret = misc_register(&ifs_devices[i].misc);
 137                 if (ret)
 138                         goto err_exit;
 139         }
 140         return 0;
 141
 142 err_exit:
 143         ifs_cleanup();
 144         return ret;
 145 }
 146
 147 static void __exit ifs_exit(void)
 148 {
 149         ifs_cleanup();
 150 }
 151
 152 module_init(ifs_init);
 153 module_exit(ifs_exit);
 154
 155 MODULE_LICENSE("GPL");
 156 MODULE_DESCRIPTION("Intel In Field Scan (IFS) device");