Heinrich, Didn't I have a tested-by and acked-by tag on this?
Cheers /Ilias On Sun, 28 Jun 2026 at 11:28, Heinrich Schuchardt <[email protected]> wrote: > > 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. > > The DSDT and FACS tables are identified via FADT. > > The following commands are provided: > > * check - parse ACPI table list\r\n", do_check > * write - save one file per ACPI table\r\n", do_write > > The file names are constructed from: > > * 4 character ACPI table name > * number if there are multiple ACPI tables of the same type > * '.dat' extension > > This matches the output of the Linux `acpidump -b` command. > > Signed-off-by: Heinrich Schuchardt <[email protected]> > --- > v3: > extend the commit message > reformat with clang-format > roll in u32_to_utf16_dec() > in add_tables() check against max_tables > v2: > Check checksums. > Check both RSDT and XSDT if both exist. > --- > lib/efi_loader/Makefile | 3 +- > lib/efi_loader/acpidump.c | 566 ++++++++++++++++++++++++++++++++++++++ > 2 files changed, 568 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..374d43d7a10 > --- /dev/null > +++ b/lib/efi_loader/acpidump.c > @@ -0,0 +1,566 @@ > +// 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; > +} > + > +/** > + * 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 > + * @max_tables: size of the table array > + * @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, > + u32 max_tables, uintptr_t addr, u32 len, > + const char *sig) > +{ > + struct acpi_dump_table *table = &tables[*table_count]; > + > + if (*table_count >= max_tables) { > + error(u"add_table: buffer too small\r\n"); > + > + return EFI_BUFFER_TOO_SMALL; > + } > + > + 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, max_tables, (uintptr_t)rsdp, > + rsdp_len, "RSDP"); > + if (ret != EFI_SUCCESS) > + goto err_out; > + > + ret = add_table(tables, table_count, max_tables, 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, max_tables, 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, > max_tables, > + 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, > max_tables, > + 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; > + > + append_uint_dec(num, 0, 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 >
