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// SPDX-License-Identifier: GPL-2.0
#define BOOT_CTYPE_H
#include "misc.h"
#include "error.h"
#include "../string.h"
#include <linux/efi.h>
#include <asm/efi.h>
/*
* Max length of 64-bit hex address string is 19, prefix "0x" + 16 hex
* digits, and '\0' for termination.
*/
#define MAX_ADDR_LEN 19
static acpi_physical_address get_acpi_rsdp(void)
{
acpi_physical_address addr = 0;
#ifdef CONFIG_KEXEC
char val[MAX_ADDR_LEN] = { };
int ret;
ret = cmdline_find_option("acpi_rsdp", val, MAX_ADDR_LEN);
if (ret < 0)
return 0;
if (kstrtoull(val, 16, &addr))
return 0;
#endif
return addr;
}
/* Search EFI system tables for RSDP. */
static acpi_physical_address efi_get_rsdp_addr(void)
{
acpi_physical_address rsdp_addr = 0;
#ifdef CONFIG_EFI
efi_system_table_t *systab;
struct efi_info *ei;
bool efi_64;
int size, i;
char *sig;
ei = &boot_params->efi_info;
sig = (char *)&ei->efi_loader_signature;
if (!strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) {
efi_64 = true;
} else if (!strncmp(sig, EFI32_LOADER_SIGNATURE, 4)) {
efi_64 = false;
} else {
debug_putstr("Wrong EFI loader signature.\n");
return 0;
}
/* Get systab from boot params. */
#ifdef CONFIG_X86_64
systab = (efi_system_table_t *)(ei->efi_systab | ((__u64)ei->efi_systab_hi<<32));
#else
if (ei->efi_systab_hi || ei->efi_memmap_hi) {
debug_putstr("Error getting RSDP address: EFI system table located above 4GB.\n");
return 0;
}
systab = (efi_system_table_t *)ei->efi_systab;
#endif
if (!systab)
error("EFI system table not found.");
/*
* Get EFI tables from systab.
*/
size = efi_64 ? sizeof(efi_config_table_64_t) :
sizeof(efi_config_table_32_t);
for (i = 0; i < systab->nr_tables; i++) {
acpi_physical_address table;
void *config_tables;
efi_guid_t guid;
config_tables = (void *)(systab->tables + size * i);
if (efi_64) {
efi_config_table_64_t *tmp_table;
tmp_table = config_tables;
guid = tmp_table->guid;
table = tmp_table->table;
if (!IS_ENABLED(CONFIG_X86_64) && table >> 32) {
debug_putstr("Error getting RSDP address: EFI config table located above 4GB.\n");
return 0;
}
} else {
efi_config_table_32_t *tmp_table;
tmp_table = config_tables;
guid = tmp_table->guid;
table = tmp_table->table;
}
if (!(efi_guidcmp(guid, ACPI_TABLE_GUID)))
rsdp_addr = table;
else if (!(efi_guidcmp(guid, ACPI_20_TABLE_GUID)))
return table;
}
#endif
return rsdp_addr;
}
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