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 decompressor 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_ptr);
58 if (et == EFI_TYPE_NONE)
59 return false;
60
61 ret = efi_get_conf_table(boot_params_ptr, &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_ptr, 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
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