src/soc/intel/common/block/acpi/sgx.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <acpi/acpigen.h>
   4 #include <console/console.h>
   5 #include <cpu/cpu.h>
   6 #include <intelblocks/acpi.h>
   7 #include <intelblocks/sgx.h>
   8
   9 #define SGX_RESOURCE_ENUM_CPUID_LEAF    0x12
  10 #define SGX_RESOURCE_ENUM_CPUID_SUBLEAF 0x2
  11 #define SGX_RESOURCE_ENUM_BIT           0x1
  12 #define SGX_RESOURCE_MASK_LO            0xfffff000UL
  13 #define SGX_RESOURCE_MASK_HI            0xfffffUL
  14
  15 static inline uint64_t sgx_resource(uint32_t low, uint32_t high)
  16 {
  17         uint64_t val;
  18         val = (uint64_t)(high & SGX_RESOURCE_MASK_HI) << 32;
  19         val |= low & SGX_RESOURCE_MASK_LO;
  20         return val;
  21 }
  22
  23 void sgx_fill_ssdt(void)
  24 {
  25         bool epcs = false;
  26         struct cpuid_result cpuid_regs;
  27         uint64_t emna = 0, elng = 0;
  28
  29         if (is_sgx_supported()) {
  30                 /*
  31                  * Get EPC base and size.
  32                  * Intel SDM: Table 36-6. CPUID Leaf 12H, Sub-Leaf Index 2 or
  33                  * higher for enumeration of SGX resources
  34                  */
  35                 cpuid_regs = cpuid_ext(SGX_RESOURCE_ENUM_CPUID_LEAF,
  36                                         SGX_RESOURCE_ENUM_CPUID_SUBLEAF);
  37
  38                 if (cpuid_regs.eax & SGX_RESOURCE_ENUM_BIT) {
  39                         /* EPC section enumerated */
  40                         epcs = true;
  41                         emna = sgx_resource(cpuid_regs.eax, cpuid_regs.ebx);
  42                         elng = sgx_resource(cpuid_regs.ecx, cpuid_regs.edx);
  43                 }
  44
  45                 printk(BIOS_DEBUG, "SGX: EPC status = %d base = 0x%llx len = 0x%llx\n",
  46                                    epcs, emna, elng);
  47         } else {
  48                 printk(BIOS_DEBUG, "SGX: not supported.\n");
  49         }
  50
  51         acpigen_write_scope("\\_SB.EPC");
  52         {
  53                 acpigen_write_name_byte("EPCS", epcs);
  54                 acpigen_write_name_qword("EMNA", emna);
  55                 acpigen_write_name_qword("ELNG", elng);
  56         }
  57         acpigen_pop_len();
  58 }