[PATCH 3/3] efi_loader: add ACPI table dump EFI app
Ilias Apalodimas
ilias.apalodimas at linaro.org
Fri May 22 09:11:11 CEST 2026
On Thu, 21 May 2026 at 21:50, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> 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.
>
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> ---
> lib/efi_loader/Makefile | 1 +
> lib/efi_loader/acpidump.c | 999 ++++++++++++++++++++++++++++++++++++++
> 2 files changed, 1000 insertions(+)
> create mode 100644 lib/efi_loader/acpidump.c
>
> diff --git a/lib/efi_loader/Makefile b/lib/efi_loader/Makefile
> index d73ad43951b..118566ee7ef 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
> diff --git a/lib/efi_loader/acpidump.c b/lib/efi_loader/acpidump.c
> new file mode 100644
> index 00000000000..0bc3770c85d
> --- /dev/null
> +++ b/lib/efi_loader/acpidump.c
> @@ -0,0 +1,999 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright 2026, Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> + *
> + * 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>
> +
> +#define BUFFER_SIZE 64
> +
> +struct acpi_dump_table {
> + char signature[5];
> + uintptr_t addr;
> + u32 len;
> +};
> +
> +static struct efi_simple_text_output_protocol *cout;
> +static struct efi_simple_text_input_protocol *cin;
> +static struct efi_boot_services *bs;
> +static efi_handle_t handle;
> +static struct efi_system_table *systable;
> +static const efi_guid_t acpi2_guid = EFI_ACPI_TABLE_GUID;
> +static const efi_guid_t acpi1_guid = EFI_GUID_EFI_ACPI1;
> +static const efi_guid_t loaded_image_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
> +static const efi_guid_t guid_simple_file_system_protocol =
> + EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
> +static const efi_guid_t efi_system_partition_guid = PARTITION_SYSTEM_GUID;
> +static bool nocolor;
> +
> +/**
> + * 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;
> +}
> +
> +/**
> + * color() - set foreground color
> + *
> + * @color: foreground color
> + */
> +static void color(u8 color)
> +{
> + if (!nocolor)
> + cout->set_attribute(cout, color | EFI_BACKGROUND_BLACK);
> +}
> +
> +/**
> + * print() - print string
> + *
> + * @string: text
> + */
> +static void print(u16 *string)
> +{
> + cout->output_string(cout, string);
> +}
> +
> +/**
> + * 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 == '_';
> +}
> +
> +/**
> + * ascii_to_utf16() - convert ASCII string to UTF-16
> + *
> + * @dst: destination UTF-16 buffer
> + * @dst_size: destination size in UTF-16 code units
> + * @src: source ASCII string
> + */
> +static void ascii_to_utf16(u16 *dst, efi_uintn_t dst_size, const char *src)
> +{
> + efi_uintn_t i;
> +
> + if (!dst_size)
> + return;
> +
> + for (i = 0; i < dst_size - 1 && src[i]; ++i)
> + dst[i] = (u8)src[i];
> + dst[i] = 0;
> +}
> +
> +/**
> + * append_uint_dec() - append unsigned decimal number to C string
> + *
> + * @str: destination string
> + * @pos: current write position
> + * @size: destination size
> + * @val: value to append
> + * Return: updated write position
> + */
> +static efi_uintn_t append_uint_dec(char *str, efi_uintn_t pos,
> + efi_uintn_t size, u32 val)
> +{
> + char tmp[11];
> + efi_uintn_t n = 0;
> + efi_uintn_t i;
> +
> + if (!val)
> + tmp[n++] = '0';
> + while (val && n < ARRAY_SIZE(tmp)) {
> + tmp[n++] = '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
> + *
> + * @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)
> +{
> + char ascii[11] = {0};
> +
> + append_uint_dec(ascii, 0, sizeof(ascii), val);
> + ascii_to_utf16(dst, dst_size, ascii);
> +}
> +
> +/**
> + * build_table_filename() - construct table filename
> + *
> + * @sig: 4-byte ACPI signature string
> + * @instance: duplicate instance number (0 for first)
> + * @name: output filename buffer
> + * @name_size: output filename buffer size
> + */
> +static void build_table_filename(const char *sig, u32 instance, char *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]) ? sig[i] : '_';
> +
> + if (instance)
> + pos = append_uint_dec(name, pos, name_size, instance);
> +
> + if (pos + 4 < name_size) {
> + name[pos++] = '.';
> + name[pos++] = 'd';
> + name[pos++] = 'a';
> + name[pos++] = 't';
> + }
> + name[pos] = 0;
> +}
> +
> +/**
> + * printp() - print pointer
> + *
> + * @p: pointer
> + */
> +static void printp(void *p)
> +{
> + u16 str[2 + 2 * sizeof(void *) + 1] = u"0x";
> + u16 *ptr = &str[2];
> + u16 ch;
> + int i;
> +
> + for (i = 8 * sizeof(void *) - 4; i >= 0; i -= 4) {
> + ch = ((uintptr_t)p >> i & 0xf) + '0';
> + if (ch > '9')
> + ch += 'a' - '9' - 1;
> + *ptr++ = ch;
> + }
> + *ptr = 0;
> + print(str);
> +}
> +
> +/**
> + * cls() - clear screen
> + */
> +static void cls(void)
> +{
> + if (nocolor)
> + print(u"\r\n");
> + else
> + cout->clear_screen(cout);
> +}
> +
> +/**
> + * error() - print error string
> + *
> + * @string: error text
> + */
> +static void error(u16 *string)
> +{
> + color(EFI_LIGHTRED);
> + print(string);
> + color(EFI_LIGHTBLUE);
> +}
> +
> +/**
> + * efi_input_yn() - get answer to yes/no question
> + *
> + * Return:
> + * y or Y
> + * EFI_SUCCESS
> + * n or N
> + * EFI_ACCESS_DENIED
> + * ESC
> + * EFI_ABORTED
> + */
> +static efi_status_t efi_input_yn(void)
> +{
> + struct efi_input_key key = {0};
> + efi_uintn_t index;
> + efi_status_t ret;
> +
> + /* Drain the console input */
> + ret = cin->reset(cin, true);
> + for (;;) {
> + ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
> + if (ret != EFI_SUCCESS)
> + continue;
> + ret = cin->read_key_stroke(cin, &key);
> + if (ret != EFI_SUCCESS)
> + continue;
> + switch (key.scan_code) {
> + case 0x17: /* Escape */
> + return EFI_ABORTED;
> + default:
> + break;
> + }
> + /* Convert to lower case */
> + switch (key.unicode_char | 0x20) {
> + case 'y':
> + return EFI_SUCCESS;
> + case 'n':
> + return EFI_ACCESS_DENIED;
> + default:
> + break;
> + }
> + }
> +}
> +
> +/**
> + * efi_input() - read string from console
> + *
> + * @buffer: input buffer
> + * @buffer_size: buffer size
> + * Return: status code
> + */
> +static efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
> +{
> + struct efi_input_key key = {0};
> + efi_uintn_t index;
> + efi_uintn_t pos = 0;
> + u16 outbuf[2] = u" ";
> + efi_status_t ret;
> +
> + /* Drain the console input */
> + ret = cin->reset(cin, true);
> + *buffer = 0;
> + for (;;) {
> + ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
> + if (ret != EFI_SUCCESS)
> + continue;
> + ret = cin->read_key_stroke(cin, &key);
> + if (ret != EFI_SUCCESS)
> + continue;
> + switch (key.scan_code) {
> + case 0x17: /* Escape */
> + print(u"\r\nAborted\r\n");
> + return EFI_ABORTED;
> + default:
> + break;
> + }
> + switch (key.unicode_char) {
> + case 0x08: /* Backspace */
> + if (pos) {
> + buffer[pos--] = 0;
> + print(u"\b \b");
> + }
> + break;
> + case 0x0a: /* Linefeed */
> + case 0x0d: /* Carriage return */
> + print(u"\r\n");
> + return EFI_SUCCESS;
> + default:
> + break;
> + }
> + /* Ignore surrogate codes */
> + if (key.unicode_char >= 0xD800 && key.unicode_char <= 0xDBFF)
> + continue;
> + if (key.unicode_char >= 0x20 &&
> + pos < buffer_size - 1) {
> + *outbuf = key.unicode_char;
> + buffer[pos++] = key.unicode_char;
> + buffer[pos] = 0;
> + print(outbuf);
> + }
> + }
> +}
> +
> +/**
> + * skip_whitespace() - skip over leading whitespace
> + *
> + * @pos: UTF-16 string
> + * Return: pointer to first non-whitespace
> + */
> +static u16 *skip_whitespace(u16 *pos)
> +{
> + for (; *pos && *pos <= 0x20; ++pos)
> + ;
> + return pos;
> +}
> +
> +/**
> + * starts_with() - check if @string starts with @keyword
> + *
> + * @string: string to search for keyword
> + * @keyword: keyword to be searched
> + * Return: true fi @string starts with the keyword
> + */
> +static bool starts_with(u16 *string, u16 *keyword)
> +{
> + if (!string || !keyword)
> + return false;
> +
> + for (; *keyword; ++string, ++keyword) {
> + if (*string != *keyword)
> + return false;
> + }
> + return true;
> +}
> +
> +/**
> + * open_file_system() - open simple file system protocol
> + *
> + * file_system: interface of the simple file system protocol
> + * Return: status code
> + */
> +static efi_status_t
> +open_file_system(struct efi_simple_file_system_protocol **file_system)
> +{
> + struct efi_loaded_image *loaded_image;
> + efi_status_t ret;
> + efi_handle_t *handle_buffer = NULL;
> + efi_uintn_t count;
> +
> + ret = bs->open_protocol(handle, &loaded_image_guid,
> + (void **)&loaded_image, NULL, NULL,
> + EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> + if (ret != EFI_SUCCESS) {
> + error(u"Loaded image protocol not found\r\n");
> + return ret;
> + }
> +
> + /* Open the simple file system protocol on the same partition */
> + ret = bs->open_protocol(loaded_image->device_handle,
> + &guid_simple_file_system_protocol,
> + (void **)file_system, NULL, NULL,
> + EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> + if (ret == EFI_SUCCESS)
> + return ret;
> +
> + /* Open the simple file system protocol on the UEFI system partition */
> + ret = bs->locate_handle_buffer(BY_PROTOCOL, &efi_system_partition_guid,
> + NULL, &count, &handle_buffer);
> + if (ret == EFI_SUCCESS && handle_buffer)
> + ret = bs->open_protocol(handle_buffer[0],
> + &guid_simple_file_system_protocol,
> + (void **)file_system, NULL, NULL,
> + EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> + if (ret != EFI_SUCCESS)
> + error(u"Failed to open simple file system protocol\r\n");
> + if (handle_buffer)
> + bs->free_pool(handle_buffer);
> +
> + return ret;
> +}
> +
> +/**
> + * do_help() - print help
> + */
> +static void do_help(void)
> +{
> + error(u"check - parse ACPI table list\r\n");
> + error(u"write - save one file per ACPI table\r\n");
> + error(u"exit - exit the shell\r\n");
> +}
> +
> +/**
> + * get_config_table() - get configuration table
> + *
> + * @guid: GUID of the configuration table
> + * Return: pointer to configuration table or NULL
> + */
> +static void *get_config_table(const efi_guid_t *guid)
> +{
> + size_t i;
> +
> + for (i = 0; i < systable->nr_tables; ++i) {
> + if (!memcmp(guid, &systable->tables[i].guid, sizeof(*guid)))
> + return systable->tables[i].table;
> + }
> +
> + return NULL;
> +}
> +
> +/**
> + * 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();
> + print(u"RSDP address: ");
> + printp(rsdp);
> + print(u"\r\n");
> + if (!rsdp) {
> + error(u"No ACPI configuration table\r\n");
> + return EFI_NOT_FOUND;
> + }
> +
> + 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;
> +
> + dsdt_addr = read_u64(&fadt->x_dsdt);
> + 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;
> + 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;
> + }
> +
> + facs_addr = read_u64(&fadt->x_firmware_ctrl);
> + 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;
> +}
> +
> +/**
> + * save_file() - save file to EFI system partition
> + *
> + * @filename: file name
> + * @buf: buffer to write
> + * @size: size of the buffer
> + */
> +static efi_status_t save_file(u16 *filename, void *buf, efi_uintn_t size)
> +{
> + efi_uintn_t ret;
> + struct efi_simple_file_system_protocol *file_system;
> + struct efi_file_handle *root, *file;
> +
> + ret = open_file_system(&file_system);
> + if (ret != EFI_SUCCESS)
> + return ret;
> +
> + /* Open volume */
> + ret = file_system->open_volume(file_system, &root);
> + if (ret != EFI_SUCCESS) {
> + error(u"Failed to open volume\r\n");
> + return ret;
> + }
> + /* Check if file already exists */
> + ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
> + if (ret == EFI_SUCCESS) {
> + file->close(file);
> + print(u"Overwrite existing file (y/n)? ");
> + ret = efi_input_yn();
> + print(u"\r\n");
> + if (ret != EFI_SUCCESS) {
> + root->close(root);
> + error(u"Aborted by user\r\n");
> + return ret;
> + }
> + }
> +
> + /* Create file */
> + ret = root->open(root, &file, filename,
> + EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE |
> + EFI_FILE_MODE_CREATE, EFI_FILE_ARCHIVE);
> + if (ret == EFI_SUCCESS) {
> + /* Write file */
> + ret = file->write(file, &size, buf);
> + if (ret != EFI_SUCCESS)
> + error(u"Failed to write file\r\n");
> + file->close(file);
> + } else {
> + error(u"Failed to open file\r\n");
> + }
> + root->close(root);
> +
> + return ret;
> +}
> +
> +/**
> + * do_check() - parse ACPI tables and report success/failure
> + *
> + * Return: status code
> + */
> +static efi_status_t do_check(void)
> +{
> + 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 ret;
> +
> + if (!table_count) {
> + print(u"No ACPI tables found\r\n");
> + return EFI_NOT_FOUND;
> + }
> +
> + 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);
> +
> + return EFI_SUCCESS;
> +}
> +
> +/**
> + * do_write() - ask filename and save ACPI table set
> + *
> + * Return: status code
> + */
> +static efi_status_t do_write(void)
> +{
> + struct acpi_dump_table *tables;
> + u16 filename[BUFFER_SIZE];
> + char ascii_name[BUFFER_SIZE];
> + u32 table_count;
> + u32 i;
> + efi_status_t ret;
> +
> + ret = collect_tables(&tables, &table_count);
> + if (ret != EFI_SUCCESS)
> + return ret;
> + if (!table_count) {
> + print(u"No ACPI tables found\r\n");
> + bs->free_pool(tables);
> + return EFI_NOT_FOUND;
> + }
> +
> + 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, ascii_name,
> + ARRAY_SIZE(ascii_name));
> + ascii_to_utf16(filename, ARRAY_SIZE(filename), ascii_name);
> +
> + 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_SUCCESS)
> + break;
> + }
> +
> + bs->free_pool(tables);
> +
> + return ret;
> +}
> +
> +/**
> + * get_load_options() - get load options
> + *
> + * Return: load options or NULL
> + */
> +static u16 *get_load_options(void)
> +{
> + efi_status_t ret;
> + struct efi_loaded_image *loaded_image;
> +
> + ret = bs->open_protocol(handle, &loaded_image_guid,
> + (void **)&loaded_image, NULL, NULL,
> + EFI_OPEN_PROTOCOL_GET_PROTOCOL);
> + if (ret != EFI_SUCCESS) {
> + error(u"Loaded image protocol not found\r\n");
> + return NULL;
> + }
> +
> + if (!loaded_image->load_options_size || !loaded_image->load_options)
> + return NULL;
> +
> + return loaded_image->load_options;
> +}
> +
> +/**
> + * command_loop() - process user commands
> + */
> +static void command_loop(void)
> +{
> + for (;;) {
> + u16 command[BUFFER_SIZE];
> + u16 *pos;
> + efi_status_t ret;
> +
> + print(u"=> ");
> + ret = efi_input(command, ARRAY_SIZE(command));
> + if (ret == EFI_ABORTED)
> + break;
> + pos = skip_whitespace(command);
> + if (starts_with(pos, u"exit")) {
> + break;
> + } else if (starts_with(pos, u"check")) {
> + ret = do_check();
> + if (ret == EFI_SUCCESS)
> + print(u"OK\r\n");
> + } else if (starts_with(pos, u"write")) {
> + do_write();
> + } else {
> + do_help();
> + }
> + }
> +}
> +
> +/**
> + * efi_main() - entry point of the EFI application.
> + *
> + * @handle: handle of the loaded image
> + * @systab: system table
> + * Return: status code
> + */
> +efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
> + struct efi_system_table *systab)
> +{
> + u16 *load_options;
> +
> + handle = image_handle;
> + systable = systab;
> + cout = systable->con_out;
> + cin = systable->con_in;
> + bs = systable->boottime;
> + load_options = get_load_options();
> +
> + if (starts_with(load_options, u"nocolor"))
> + nocolor = true;
> +
> + color(EFI_WHITE);
> + cls();
> + print(u"ACPI Dump\r\n=========\r\n\r\n");
> + color(EFI_LIGHTBLUE);
> +
> + command_loop();
> +
> + color(EFI_LIGHTGRAY);
> + cls();
> +
> + return EFI_SUCCESS;
> +}
> --
> 2.53.0
>
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