Provide an EFI binary that can dump all ACPI tables to files <table_name>.dat. These can then be further analyzed by decompiling with iasl.
Signed-off-by: Heinrich Schuchardt <[email protected]> --- v2: Check checksums. Check both RSDT and XSDT if both exist. --- lib/efi_loader/Makefile | 3 +- lib/efi_loader/acpidump.c | 563 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 565 insertions(+), 1 deletion(-) create mode 100644 lib/efi_loader/acpidump.c diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile index 94ad6721a70..b9a3433a0c5 100644 --- a/lib/efi_loader/Makefile +++ b/lib/efi_loader/Makefile @@ -16,6 +16,7 @@ CFLAGS_efi_boottime.o += \ apps-$(CONFIG_RISCV) += boothart apps-$(CONFIG_BOOTEFI_HELLO_COMPILE) += helloworld apps-$(CONFIG_GENERATE_SMBIOS_TABLE) += smbiosdump +apps-$(CONFIG_GENERATE_ACPI_TABLE) += acpidump apps-$(CONFIG_EFI_LOAD_FILE2_INITRD) += initrddump ifeq ($(CONFIG_GENERATE_ACPI_TABLE),) apps-y += dtbdump @@ -103,7 +104,7 @@ $(foreach f,$(apps-y) $(efi-obj-y),\ $(eval CFLAGS_REMOVE_$(f).o := $(CFLAGS_NON_EFI))) # Link efi_app_common.o into each dump app -$(obj)/dbginfodump_efi.so $(obj)/dtbdump_efi.so \ +$(obj)/acpidump_efi.so $(obj)/dbginfodump_efi.so $(obj)/dtbdump_efi.so \ $(obj)/initrddump_efi.so $(obj)/smbiosdump_efi.so: $(obj)/efi_app_common.o always-y += $(foreach f,$(apps-y),$(f).efi) diff --git a/lib/efi_loader/acpidump.c b/lib/efi_loader/acpidump.c new file mode 100644 index 00000000000..3e5635fce5a --- /dev/null +++ b/lib/efi_loader/acpidump.c @@ -0,0 +1,563 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2026, Heinrich Schuchardt <[email protected]> + * + * acpidump.efi saves the ACPI table set as file. + * + * Specifying 'nocolor' as load option data suppresses colored output and + * clearing of the screen. + */ + +#include <efi_api.h> +#include <part.h> +#include <string.h> +#include <acpi/acpi_table.h> +#include "efi_app_common.h" + +#define MAX_FILENAME_LENGTH 32 + +u16 app_banner[] = u"ACPI Dump\r\n=========\r\n\r\n"; + +struct acpi_dump_table { + char signature[5]; + uintptr_t addr; + u32 len; +}; + +static const efi_guid_t acpi2_guid = EFI_ACPI_TABLE_GUID; +static const efi_guid_t acpi1_guid = EFI_GUID_EFI_ACPI1; + +/** + * checksum_ok() - check if byte-sum of buffer is zero + * + * @buf: buffer to check + * @len: buffer length + * Return: true if checksum is valid + */ +static bool checksum_ok(const void *buf, efi_uintn_t len) +{ + const u8 *pos = buf; + u8 sum = 0; + + for (; len; --len, ++pos) + sum += *pos; + + return !sum; +} + +/** + * read_u32() - read 32-bit value via memcpy + * + * @src: source address + * Return: value + */ +static u32 read_u32(const void *src) +{ + u32 val; + + memcpy(&val, src, sizeof(val)); + + return val; +} + +/** + * read_u64() - read 64-bit value via memcpy + * + * @src: source address + * Return: value + */ +static u64 read_u64(const void *src) +{ + u64 val; + + memcpy(&val, src, sizeof(val)); + + return val; +} + +/** + * is_filename_char() - check if a signature byte is filename-safe + * + * @ch: character to check + * Return: true if filename-safe + */ +static bool is_filename_char(char ch) +{ + return (ch >= 'A' && ch <= 'Z') || + (ch >= 'a' && ch <= 'z') || + (ch >= '0' && ch <= '9') || ch == '_'; +} + +/** + * append_uint_dec() - append decimal representation of integer to UTF-16 string + * + * @str: destination UTF-16 string + * @pos: current write position + * @size: destination size in UTF-16 code units + * @val: value to append + * Return: updated write position + */ +static efi_uintn_t append_uint_dec(u16 *str, efi_uintn_t pos, + efi_uintn_t size, u32 val) +{ + u16 tmp[11]; + efi_uintn_t n = 0; + efi_uintn_t i; + + if (!val) + tmp[n++] = u'0'; + while (val && n < ARRAY_SIZE(tmp)) { + tmp[n++] = u'0' + val % 10; + val /= 10; + } + + for (i = 0; i < n && pos + 1 < size; ++i) + str[pos++] = tmp[n - i - 1]; + + if (pos < size) + str[pos] = 0; + + return pos; +} + +/** + * u32_to_utf16_dec() - convert unsigned integer to UTF-16 decimal string + * + * @dst: destination UTF-16 buffer + * @dst_size: destination size in UTF-16 code units + * @val: value to convert + */ +static void u32_to_utf16_dec(u16 *dst, efi_uintn_t dst_size, u32 val) +{ + append_uint_dec(dst, 0, dst_size, val); +} + +/** + * build_table_filename() - construct table filename + * + * @sig: 4-byte ACPI signature string + * @instance: duplicate instance number (0 for first) + * @name: output filename buffer (UTF-16) + * @name_size: output filename buffer size in UTF-16 code units + */ +static void build_table_filename(const char *sig, u32 instance, u16 *name, + efi_uintn_t name_size) +{ + efi_uintn_t pos = 0; + int i; + + if (!name_size) + return; + + for (i = 0; i < 4 && pos + 1 < name_size; ++i) + name[pos++] = is_filename_char(sig[i]) ? (u16)sig[i] : u'_'; + + if (instance) + pos = append_uint_dec(name, pos, name_size, instance); + + if (pos + 4 < name_size) { + name[pos++] = u'.'; + name[pos++] = u'd'; + name[pos++] = u'a'; + name[pos++] = u't'; + } + name[pos] = 0; +} + +/** + * get_acpi_rsdp_addr() - find ACPI RSDP via EFI config table GUID + * + * Return: pointer to RSDP or NULL + */ +static struct acpi_rsdp *get_acpi_rsdp_addr(void) +{ + struct acpi_rsdp *rsdp; + + rsdp = get_config_table(&acpi2_guid); + if (rsdp) + return rsdp; + + rsdp = get_config_table(&acpi1_guid); + + return rsdp; +} + +/** + * add_table() - append one ACPI table entry + * + * @tables: table array + * @table_count: current table count + * @addr: table address + * @len: table length + * @sig: 4-character ACPI signature + * Return: status code + */ +static efi_status_t add_table(struct acpi_dump_table *tables, u32 *table_count, + uintptr_t addr, u32 len, const char *sig) +{ + struct acpi_dump_table *table = &tables[*table_count]; + + memset(table, 0, sizeof(*table)); + memcpy(table->signature, sig, 4); + table->addr = addr; + table->len = len; + ++*table_count; + + return EFI_SUCCESS; +} + +/** + * has_table_addr() - check if a table address is already in the list + * + * @tables: table array + * @table_count: number of used entries + * @addr: table address to search + * Return: true if found + */ +static bool has_table_addr(struct acpi_dump_table *tables, u32 table_count, + uintptr_t addr) +{ + u32 i; + + for (i = 0; i < table_count; ++i) { + if (tables[i].addr == addr) + return true; + } + + return false; +} + +/** + * collect_tables() - parse ACPI table structure and collect ACPI tables + * + * @tablesp: output table array + * @table_count: output table count + * Return: status code + */ +static efi_status_t collect_tables(struct acpi_dump_table **tablesp, + u32 *table_count) +{ + struct acpi_rsdp *rsdp; + struct acpi_table_header *root; + struct acpi_dump_table *tables; + uintptr_t root_addr; + u32 rsdp_len, root_len, max_tables; + u32 i, entries, entry_size; + bool use_xsdt; + efi_status_t ret; + + rsdp = get_acpi_rsdp_addr(); + if (!rsdp) { + error(u"No ACPI configuration table\r\n"); + return EFI_NOT_FOUND; + } + print(u"RSDP address: 0x"); + printx((uintptr_t)rsdp, 2 * sizeof(void *)); + print(u"\r\n"); + + if (memcmp(rsdp->signature, RSDP_SIG, sizeof(rsdp->signature))) { + error(u"Invalid RSDP signature\r\n"); + return EFI_LOAD_ERROR; + } + if (!checksum_ok(rsdp, 20)) { + error(u"Invalid RSDP checksum\r\n"); + return EFI_LOAD_ERROR; + } + + rsdp_len = rsdp->revision >= ACPI_RSDP_REV_ACPI_2_0 ? + read_u32(&rsdp->length) : 20; + if (rsdp_len < 20) { + error(u"Invalid RSDP length\r\n"); + return EFI_LOAD_ERROR; + } + if (rsdp->revision >= ACPI_RSDP_REV_ACPI_2_0) { + if (rsdp_len < sizeof(struct acpi_rsdp)) { + error(u"Invalid ACPI 2.0 RSDP length\r\n"); + return EFI_LOAD_ERROR; + } + if (!checksum_ok(rsdp, rsdp_len)) { + error(u"Invalid ACPI 2.0 RSDP checksum\r\n"); + return EFI_LOAD_ERROR; + } + } + + if (rsdp->revision >= ACPI_RSDP_REV_ACPI_2_0 && + read_u64(&rsdp->xsdt_address)) { + root_addr = read_u64(&rsdp->xsdt_address); + use_xsdt = true; + } else { + root_addr = read_u32(&rsdp->rsdt_address); + use_xsdt = false; + } + + if (!root_addr) { + error(u"Invalid RSDT/XSDT address\r\n"); + return EFI_LOAD_ERROR; + } + + root = (struct acpi_table_header *)root_addr; + root_len = read_u32(&root->length); + if (root_len < sizeof(*root)) { + error(u"Invalid RSDT/XSDT length\r\n"); + return EFI_LOAD_ERROR; + } + if (use_xsdt && memcmp(root->signature, "XSDT", 4)) { + error(u"Invalid XSDT signature\r\n"); + return EFI_LOAD_ERROR; + } + if (!use_xsdt && memcmp(root->signature, "RSDT", 4)) { + error(u"Invalid RSDT signature\r\n"); + return EFI_LOAD_ERROR; + } + if (!checksum_ok(root, root_len)) { + error(u"Invalid RSDT/XSDT checksum\r\n"); + return EFI_LOAD_ERROR; + } + + entry_size = use_xsdt ? sizeof(u64) : sizeof(u32); + if ((root_len - sizeof(*root)) % entry_size) { + error(u"Invalid RSDT/XSDT entry list\r\n"); + return EFI_LOAD_ERROR; + } + entries = (root_len - sizeof(*root)) / entry_size; + /* RSDP + root + each root entry + up to DSDT/FACS per entry */ + max_tables = 2 + 3 * entries; + + ret = bs->allocate_pool(EFI_LOADER_DATA, + max_tables * sizeof(struct acpi_dump_table), + (void **)&tables); + if (ret != EFI_SUCCESS) { + error(u"Out of memory\r\n"); + return ret; + } + *table_count = 0; + + ret = add_table(tables, table_count, (uintptr_t)rsdp, rsdp_len, "RSDP"); + if (ret != EFI_SUCCESS) + goto err_out; + + ret = add_table(tables, table_count, root_addr, root_len, root->signature); + if (ret != EFI_SUCCESS) + goto err_out; + + for (i = 0; i < entries; ++i) { + uintptr_t addr; + struct acpi_table_header *table; + u32 len; + + if (use_xsdt) { + u64 *entry = (u64 *)((u8 *)root + sizeof(*root)); + + addr = read_u64(&entry[i]); + } else { + u32 *entry = (u32 *)((u8 *)root + sizeof(*root)); + + addr = read_u32(&entry[i]); + } + if (!addr) + continue; + if (has_table_addr(tables, *table_count, addr)) + continue; + + table = (struct acpi_table_header *)addr; + len = read_u32(&table->length); + if (len < sizeof(*table)) { + error(u"Invalid ACPI table length\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + if (!checksum_ok(table, len)) { + error(u"Invalid ACPI table checksum\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + + ret = add_table(tables, table_count, addr, len, table->signature); + if (ret != EFI_SUCCESS) + goto err_out; + + /* + * FADT (signature FACP) references DSDT and FACS outside RSDT/XSDT. + * Include them so output matches acpidump -b style completeness. + */ + if (!memcmp(table->signature, "FACP", 4)) { + struct acpi_fadt *fadt = (struct acpi_fadt *)table; + uintptr_t dsdt_addr; + uintptr_t facs_addr; + + if (len >= offsetof(struct acpi_fadt, x_dsdt) + + sizeof(fadt->x_dsdt)) + dsdt_addr = read_u64(&fadt->x_dsdt); + else + dsdt_addr = 0; + if (!dsdt_addr) + dsdt_addr = read_u32(&fadt->dsdt); + if (dsdt_addr && !has_table_addr(tables, *table_count, + dsdt_addr)) { + struct acpi_table_header *dsdt; + u32 dsdt_len; + + dsdt = (struct acpi_table_header *)dsdt_addr; + if (memcmp(dsdt->signature, "DSDT", 4)) { + error(u"Invalid DSDT signature\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + dsdt_len = read_u32(&dsdt->length); + if (dsdt_len < sizeof(*dsdt)) { + error(u"Invalid DSDT length\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + if (!checksum_ok(dsdt, dsdt_len)) { + error(u"Invalid DSDT checksum\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + + ret = add_table(tables, table_count, dsdt_addr, dsdt_len, + dsdt->signature); + if (ret != EFI_SUCCESS) + goto err_out; + } + + if (len >= offsetof(struct acpi_fadt, x_firmware_ctrl) + + sizeof(fadt->x_firmware_ctrl)) + facs_addr = read_u64(&fadt->x_firmware_ctrl); + else + facs_addr = 0; + if (!facs_addr) + facs_addr = read_u32(&fadt->firmware_ctrl); + if (facs_addr && !has_table_addr(tables, *table_count, + facs_addr)) { + struct acpi_facs *facs; + u32 facs_len; + + facs = (struct acpi_facs *)facs_addr; + if (memcmp(facs->signature, "FACS", 4)) { + error(u"Invalid FACS signature\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + facs_len = read_u32(&facs->length); + if (facs_len < sizeof(*facs)) { + error(u"Invalid FACS length\r\n"); + ret = EFI_LOAD_ERROR; + goto err_out; + } + ret = add_table(tables, table_count, facs_addr, facs_len, + facs->signature); + if (ret != EFI_SUCCESS) + goto err_out; + } + } + } + + *tablesp = tables; + + return EFI_SUCCESS; + +err_out: + bs->free_pool(tables); + return ret; +} + +/** + * do_check() - parse ACPI tables and report success/failure + * + * @args: unused command arguments + */ +static void do_check(u16 * __maybe_unused args) +{ + struct acpi_dump_table *tables; + u32 table_count; + u16 num[11] = {0}; + efi_status_t ret; + + ret = collect_tables(&tables, &table_count); + if (ret != EFI_SUCCESS) + return; + + u32_to_utf16_dec(num, ARRAY_SIZE(num), table_count); + + print(u"ACPI tables found: "); + print(num); + print(u"\r\n"); + + bs->free_pool(tables); + print(u"OK\r\n"); +} + +/** + * do_write() - ask filename and save ACPI table set + * + * @args: unused command arguments + */ +static void do_write(u16 * __maybe_unused args) +{ + struct acpi_dump_table *tables; + u16 filename[MAX_FILENAME_LENGTH]; + u32 table_count; + u32 i; + efi_status_t ret; + + ret = collect_tables(&tables, &table_count); + if (ret != EFI_SUCCESS) + return; + if (!table_count) { + print(u"No ACPI tables found\r\n"); + bs->free_pool(tables); + return; + } + + for (i = 0; i < table_count; ++i) { + u8 *buf; + u32 instance = 0; + u32 same_type = 0; + u32 j; + + for (j = 0; j < table_count; ++j) { + if (!memcmp(tables[i].signature, tables[j].signature, 4)) + ++same_type; + } + + if (same_type > 1) { + /* Number duplicates starting at 1 for the first instance. */ + for (j = 0; j <= i; ++j) { + if (!memcmp(tables[i].signature, tables[j].signature, 4)) + ++instance; + } + } + + build_table_filename(tables[i].signature, instance, filename, + ARRAY_SIZE(filename)); + + ret = bs->allocate_pool(EFI_LOADER_DATA, tables[i].len, + (void **)&buf); + if (ret != EFI_SUCCESS) { + error(u"Out of memory\r\n"); + break; + } + + memcpy(buf, (void *)tables[i].addr, tables[i].len); + ret = save_file(filename, buf, tables[i].len); + if (ret == EFI_SUCCESS) { + print(filename); + print(u" written\r\n"); + } + + bs->free_pool(buf); + if (ret == EFI_ACCESS_DENIED) + continue; + if (ret != EFI_SUCCESS) + break; + } + + bs->free_pool(tables); +} + +struct efi_app_cmd app_cmds[] = { + { u"check", u"check - parse ACPI table list\r\n", do_check }, + { u"write", u"write - save one file per ACPI table\r\n", do_write }, + { } +}; -- 2.53.0
