cpuid-deps.c 4.9 KB

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  1. /* Declare dependencies between CPUIDs */
  2. #include <linux/kernel.h>
  3. #include <linux/init.h>
  4. #include <linux/module.h>
  5. #include <asm/cpufeature.h>
  6. struct cpuid_dep {
  7. unsigned int feature;
  8. unsigned int depends;
  9. };
  10. /*
  11. * Table of CPUID features that depend on others.
  12. *
  13. * This only includes dependencies that can be usefully disabled, not
  14. * features part of the base set (like FPU).
  15. *
  16. * Note this all is not __init / __initdata because it can be
  17. * called from cpu hotplug. It shouldn't do anything in this case,
  18. * but it's difficult to tell that to the init reference checker.
  19. */
  20. static const struct cpuid_dep cpuid_deps[] = {
  21. { X86_FEATURE_FXSR, X86_FEATURE_FPU },
  22. { X86_FEATURE_XSAVEOPT, X86_FEATURE_XSAVE },
  23. { X86_FEATURE_XSAVEC, X86_FEATURE_XSAVE },
  24. { X86_FEATURE_XSAVES, X86_FEATURE_XSAVE },
  25. { X86_FEATURE_AVX, X86_FEATURE_XSAVE },
  26. { X86_FEATURE_PKU, X86_FEATURE_XSAVE },
  27. { X86_FEATURE_MPX, X86_FEATURE_XSAVE },
  28. { X86_FEATURE_XGETBV1, X86_FEATURE_XSAVE },
  29. { X86_FEATURE_CMOV, X86_FEATURE_FXSR },
  30. { X86_FEATURE_MMX, X86_FEATURE_FXSR },
  31. { X86_FEATURE_MMXEXT, X86_FEATURE_MMX },
  32. { X86_FEATURE_FXSR_OPT, X86_FEATURE_FXSR },
  33. { X86_FEATURE_XSAVE, X86_FEATURE_FXSR },
  34. { X86_FEATURE_XMM, X86_FEATURE_FXSR },
  35. { X86_FEATURE_XMM2, X86_FEATURE_XMM },
  36. { X86_FEATURE_XMM3, X86_FEATURE_XMM2 },
  37. { X86_FEATURE_XMM4_1, X86_FEATURE_XMM2 },
  38. { X86_FEATURE_XMM4_2, X86_FEATURE_XMM2 },
  39. { X86_FEATURE_XMM3, X86_FEATURE_XMM2 },
  40. { X86_FEATURE_PCLMULQDQ, X86_FEATURE_XMM2 },
  41. { X86_FEATURE_SSSE3, X86_FEATURE_XMM2, },
  42. { X86_FEATURE_F16C, X86_FEATURE_XMM2, },
  43. { X86_FEATURE_AES, X86_FEATURE_XMM2 },
  44. { X86_FEATURE_SHA_NI, X86_FEATURE_XMM2 },
  45. { X86_FEATURE_FMA, X86_FEATURE_AVX },
  46. { X86_FEATURE_AVX2, X86_FEATURE_AVX, },
  47. { X86_FEATURE_AVX512F, X86_FEATURE_AVX, },
  48. { X86_FEATURE_AVX512IFMA, X86_FEATURE_AVX512F },
  49. { X86_FEATURE_AVX512PF, X86_FEATURE_AVX512F },
  50. { X86_FEATURE_AVX512ER, X86_FEATURE_AVX512F },
  51. { X86_FEATURE_AVX512CD, X86_FEATURE_AVX512F },
  52. { X86_FEATURE_AVX512DQ, X86_FEATURE_AVX512F },
  53. { X86_FEATURE_AVX512BW, X86_FEATURE_AVX512F },
  54. { X86_FEATURE_AVX512VL, X86_FEATURE_AVX512F },
  55. { X86_FEATURE_AVX512VBMI, X86_FEATURE_AVX512F },
  56. { X86_FEATURE_AVX512_VBMI2, X86_FEATURE_AVX512VL },
  57. { X86_FEATURE_GFNI, X86_FEATURE_AVX512VL },
  58. { X86_FEATURE_VAES, X86_FEATURE_AVX512VL },
  59. { X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX512VL },
  60. { X86_FEATURE_AVX512_VNNI, X86_FEATURE_AVX512VL },
  61. { X86_FEATURE_AVX512_BITALG, X86_FEATURE_AVX512VL },
  62. { X86_FEATURE_AVX512_4VNNIW, X86_FEATURE_AVX512F },
  63. { X86_FEATURE_AVX512_4FMAPS, X86_FEATURE_AVX512F },
  64. { X86_FEATURE_AVX512_VPOPCNTDQ, X86_FEATURE_AVX512F },
  65. { X86_FEATURE_AVX512_VP2INTERSECT, X86_FEATURE_AVX512VL },
  66. { X86_FEATURE_CQM_OCCUP_LLC, X86_FEATURE_CQM_LLC },
  67. { X86_FEATURE_CQM_MBM_TOTAL, X86_FEATURE_CQM_LLC },
  68. { X86_FEATURE_CQM_MBM_LOCAL, X86_FEATURE_CQM_LLC },
  69. { X86_FEATURE_AVX512_BF16, X86_FEATURE_AVX512VL },
  70. { X86_FEATURE_AVX512_FP16, X86_FEATURE_AVX512BW },
  71. { X86_FEATURE_ENQCMD, X86_FEATURE_XSAVES },
  72. { X86_FEATURE_PER_THREAD_MBA, X86_FEATURE_MBA },
  73. { X86_FEATURE_SGX_LC, X86_FEATURE_SGX },
  74. { X86_FEATURE_SGX1, X86_FEATURE_SGX },
  75. { X86_FEATURE_SGX2, X86_FEATURE_SGX1 },
  76. { X86_FEATURE_XFD, X86_FEATURE_XSAVES },
  77. { X86_FEATURE_XFD, X86_FEATURE_XGETBV1 },
  78. { X86_FEATURE_AMX_TILE, X86_FEATURE_XFD },
  79. {}
  80. };
  81. static inline void clear_feature(struct cpuinfo_x86 *c, unsigned int feature)
  82. {
  83. /*
  84. * Note: This could use the non atomic __*_bit() variants, but the
  85. * rest of the cpufeature code uses atomics as well, so keep it for
  86. * consistency. Cleanup all of it separately.
  87. */
  88. if (!c) {
  89. clear_cpu_cap(&boot_cpu_data, feature);
  90. set_bit(feature, (unsigned long *)cpu_caps_cleared);
  91. } else {
  92. clear_bit(feature, (unsigned long *)c->x86_capability);
  93. }
  94. }
  95. /* Take the capabilities and the BUG bits into account */
  96. #define MAX_FEATURE_BITS ((NCAPINTS + NBUGINTS) * sizeof(u32) * 8)
  97. static void do_clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
  98. {
  99. DECLARE_BITMAP(disable, MAX_FEATURE_BITS);
  100. const struct cpuid_dep *d;
  101. bool changed;
  102. if (WARN_ON(feature >= MAX_FEATURE_BITS))
  103. return;
  104. clear_feature(c, feature);
  105. /* Collect all features to disable, handling dependencies */
  106. memset(disable, 0, sizeof(disable));
  107. __set_bit(feature, disable);
  108. /* Loop until we get a stable state. */
  109. do {
  110. changed = false;
  111. for (d = cpuid_deps; d->feature; d++) {
  112. if (!test_bit(d->depends, disable))
  113. continue;
  114. if (__test_and_set_bit(d->feature, disable))
  115. continue;
  116. changed = true;
  117. clear_feature(c, d->feature);
  118. }
  119. } while (changed);
  120. }
  121. void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int feature)
  122. {
  123. do_clear_cpu_cap(c, feature);
  124. }
  125. void setup_clear_cpu_cap(unsigned int feature)
  126. {
  127. do_clear_cpu_cap(NULL, feature);
  128. }