1 // SPDX-License-Identifier: GPL-2.0-only 2 3 #include "error.h" 4 #include "misc.h" 5 #include "tdx.h" 6 #include "sev.h" 7 #include <asm/shared/tdx.h> 8 9 /* 10 * accept_memory() and process_unaccepted_memory() called from EFI stub which 11 * runs before decompresser and its early_tdx_detect(). 12 * 13 * Enumerate TDX directly from the early users. 14 */ 15 static bool early_is_tdx_guest(void) 16 { 17 static bool once; 18 static bool is_tdx; 19 20 if (!IS_ENABLED(CONFIG_INTEL_TDX_GUEST)) 21 return false; 22 23 if (!once) { 24 u32 eax, sig[3]; 25 26 cpuid_count(TDX_CPUID_LEAF_ID, 0, &eax, 27 &sig[0], &sig[2], &sig[1]); 28 is_tdx = !memcmp(TDX_IDENT, sig, sizeof(sig)); 29 once = true; 30 } 31 32 return is_tdx; 33 } 34 35 void arch_accept_memory(phys_addr_t start, phys_addr_t end) 36 { 37 /* Platform-specific memory-acceptance call goes here */ 38 if (early_is_tdx_guest()) { 39 if (!tdx_accept_memory(start, end)) 40 panic("TDX: Failed to accept memory\n"); 41 } else if (sev_snp_enabled()) { 42 snp_accept_memory(start, end); 43 } else { 44 error("Cannot accept memory: unknown platform\n"); 45 } 46 } 47 48 bool init_unaccepted_memory(void) 49 { 50 guid_t guid = LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID; 51 struct efi_unaccepted_memory *table; 52 unsigned long cfg_table_pa; 53 unsigned int cfg_table_len; 54 enum efi_type et; 55 int ret; 56 57 et = efi_get_type(boot_params); 58 if (et == EFI_TYPE_NONE) 59 return false; 60 61 ret = efi_get_conf_table(boot_params, &cfg_table_pa, &cfg_table_len); 62 if (ret) { 63 warn("EFI config table not found."); 64 return false; 65 } 66 67 table = (void *)efi_find_vendor_table(boot_params, cfg_table_pa, 68 cfg_table_len, guid); 69 if (!table) 70 return false; 71 72 if (table->version != 1) 73 error("Unknown version of unaccepted memory table\n"); 74 75 /* 76 * In many cases unaccepted_table is already set by EFI stub, but it 77 * has to be initialized again to cover cases when the table is not 78 * allocated by EFI stub or EFI stub copied the kernel image with 79 * efi_relocate_kernel() before the variable is set. 80 * 81 * It must be initialized before the first usage of accept_memory(). 82 */ 83 unaccepted_table = table; 84 85 return true; 86 } 87