blob: 5f39cf22da79bce64f9dfca4d00cc48453a0248f [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
*
* dtbdump.efi saves the device tree provided as a configuration table
* to a file.
*/
#include <efi_api.h>
#include <efi_dt_fixup.h>
#include <part.h>
#include <linux/libfdt.h>
#define BUFFER_SIZE 64
#define ESC 0x17
#define efi_size_in_pages(size) ((size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT)
static struct efi_simple_text_output_protocol *cerr;
static struct efi_simple_text_output_protocol *cout;
static struct efi_simple_text_input_protocol *cin;
static struct efi_boot_services *bs;
static const efi_guid_t fdt_guid = EFI_FDT_GUID;
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 efi_handle_t handle;
static struct efi_system_table *systable;
static const efi_guid_t efi_dt_fixup_protocol_guid = EFI_DT_FIXUP_PROTOCOL_GUID;
static const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
static const efi_guid_t efi_system_partition_guid = PARTITION_SYSTEM_GUID;
/**
* print() - print string
*
* @string: text
*/
static void print(u16 *string)
{
cout->output_string(cout, string);
}
/**
* error() - print error string
*
* @string: error text
*/
static void error(u16 *string)
{
cout->set_attribute(cout, EFI_LIGHTRED | EFI_BACKGROUND_BLACK);
print(string);
cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
}
/**
* 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);
}
}
}
/*
* Convert FDT value to host endianness.
*
* @val FDT value
* Return: converted value
*/
static u32 f2h(fdt32_t val)
{
char *buf = (char *)&val;
char i;
/* Swap the bytes */
i = buf[0]; buf[0] = buf[3]; buf[3] = i;
i = buf[1]; buf[1] = buf[2]; buf[2] = i;
return *(u32 *)buf;
}
/**
* get_dtb() - get device tree
*
* @systable: system table
* Return: device tree or NULL
*/
void *get_dtb(struct efi_system_table *systable)
{
void *dtb = NULL;
efi_uintn_t i;
for (i = 0; i < systable->nr_tables; ++i) {
if (!memcmp(&systable->tables[i].guid, &fdt_guid,
sizeof(efi_guid_t))) {
dtb = systable->tables[i].table;
break;
}
}
return dtb;
}
/**
* skip_whitespace() - skip over leading whitespace
*
* @pos: UTF-16 string
* Return: pointer to first non-whitespace
*/
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
*/
bool starts_with(u16 *string, u16 *keyword)
{
for (; *keyword; ++string, ++keyword) {
if (*string != *keyword)
return false;
}
return true;
}
/**
* do_help() - print help
*/
void do_help(void)
{
error(u"load <dtb> - load device-tree from file\r\n");
error(u"save <dtb> - save device-tree to file\r\n");
error(u"exit - exit the shell\r\n");
}
/**
* 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)
bs->free_pool(handle_buffer);
return ret;
}
/**
* do_load() - load and install device-tree
*
* @filename: file name
* Return: status code
*/
efi_status_t do_load(u16 *filename)
{
struct efi_dt_fixup_protocol *dt_fixup_prot;
struct efi_simple_file_system_protocol *file_system;
struct efi_file_handle *root = NULL, *file = NULL;
u64 addr = 0;
struct efi_file_info *info;
struct fdt_header *dtb;
efi_uintn_t buffer_size;
efi_uintn_t pages;
efi_status_t ret, ret2;
ret = bs->locate_protocol(&efi_dt_fixup_protocol_guid, NULL,
(void **)&dt_fixup_prot);
if (ret != EFI_SUCCESS) {
error(u"Device-tree fix-up protocol not found\r\n");
return ret;
}
filename = skip_whitespace(filename);
ret = open_file_system(&file_system);
if (ret != EFI_SUCCESS)
goto out;
/* Open volume */
ret = file_system->open_volume(file_system, &root);
if (ret != EFI_SUCCESS) {
error(u"Failed to open volume\r\n");
goto out;
}
/* Open file */
ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
if (ret != EFI_SUCCESS) {
error(u"File not found\r\n");
goto out;
}
/* Get file size */
buffer_size = 0;
ret = file->getinfo(file, &efi_file_info_guid, &buffer_size, NULL);
if (ret != EFI_BUFFER_TOO_SMALL) {
error(u"Can't get file info size\r\n");
goto out;
}
ret = bs->allocate_pool(EFI_LOADER_DATA, buffer_size, (void **)&info);
if (ret != EFI_SUCCESS) {
error(u"Out of memory\r\n");
goto out;
}
ret = file->getinfo(file, &efi_file_info_guid, &buffer_size, info);
if (ret != EFI_SUCCESS) {
error(u"Can't get file info\r\n");
goto out;
}
buffer_size = info->file_size;
pages = efi_size_in_pages(buffer_size);
ret = bs->free_pool(info);
if (ret != EFI_SUCCESS)
error(u"Can't free memory pool\r\n");
/* Read file */
ret = bs->allocate_pages(EFI_ALLOCATE_ANY_PAGES,
EFI_ACPI_RECLAIM_MEMORY,
pages, &addr);
if (ret != EFI_SUCCESS) {
error(u"Out of memory\r\n");
goto out;
}
dtb = (struct fdt_header *)(uintptr_t)addr;
ret = file->read(file, &buffer_size, dtb);
if (ret != EFI_SUCCESS) {
error(u"Can't read file\r\n");
goto out;
}
/* Fixup file, expecting EFI_BUFFER_TOO_SMALL */
ret = dt_fixup_prot->fixup(dt_fixup_prot, dtb, &buffer_size,
EFI_DT_APPLY_FIXUPS | EFI_DT_RESERVE_MEMORY |
EFI_DT_INSTALL_TABLE);
if (ret == EFI_BUFFER_TOO_SMALL) {
/* Read file into larger buffer */
ret = bs->free_pages(addr, pages);
if (ret != EFI_SUCCESS)
error(u"Can't free memory pages\r\n");
pages = efi_size_in_pages(buffer_size);
ret = bs->allocate_pages(EFI_ALLOCATE_ANY_PAGES,
EFI_ACPI_RECLAIM_MEMORY,
pages, &addr);
if (ret != EFI_SUCCESS) {
error(u"Out of memory\r\n");
goto out;
}
dtb = (struct fdt_header *)(uintptr_t)addr;
ret = file->setpos(file, 0);
if (ret != EFI_SUCCESS) {
error(u"Can't position file\r\n");
goto out;
}
ret = file->read(file, &buffer_size, dtb);
if (ret != EFI_SUCCESS) {
error(u"Can't read file\r\n");
goto out;
}
buffer_size = pages << EFI_PAGE_SHIFT;
ret = dt_fixup_prot->fixup(
dt_fixup_prot, dtb, &buffer_size,
EFI_DT_APPLY_FIXUPS | EFI_DT_RESERVE_MEMORY |
EFI_DT_INSTALL_TABLE);
}
if (ret == EFI_SUCCESS)
print(u"device-tree installed\r\n");
else
error(u"Device-tree fix-up failed\r\n");
out:
if (addr) {
ret2 = bs->free_pages(addr, pages);
if (ret2 != EFI_SUCCESS)
error(u"Can't free memory pages\r\n");
}
if (file) {
ret2 = file->close(file);
if (ret2 != EFI_SUCCESS)
error(u"Can't close file\r\n");
}
if (root) {
ret2 = root->close(root);
if (ret2 != EFI_SUCCESS)
error(u"Can't close volume\r\n");
}
return ret;
}
/**
* do_save() - save current device-tree
*
* @filename: file name
* Return: status code
*/
efi_status_t do_save(u16 *filename)
{
struct efi_simple_file_system_protocol *file_system;
efi_uintn_t dtb_size;
struct efi_file_handle *root, *file;
struct fdt_header *dtb;
efi_uintn_t ret;
dtb = get_dtb(systable);
if (!dtb) {
error(u"DTB not found\r\n");
return EFI_NOT_FOUND;
}
if (f2h(dtb->magic) != FDT_MAGIC) {
error(u"Wrong device tree magic\r\n");
return EFI_NOT_FOUND;
}
dtb_size = f2h(dtb->totalsize);
filename = skip_whitespace(filename);
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, &dtb_size, dtb);
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);
if (ret == EFI_SUCCESS) {
print(filename);
print(u" written\r\n");
}
return ret;
}
/**
* 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)
{
handle = image_handle;
systable = systab;
cerr = systable->std_err;
cout = systable->con_out;
cin = systable->con_in;
bs = systable->boottime;
cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
cout->clear_screen(cout);
cout->set_attribute(cout, EFI_WHITE | EFI_BACKGROUND_BLACK);
print(u"DTB Dump\r\n========\r\n\r\n");
cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
for (;;) {
u16 command[BUFFER_SIZE];
u16 *pos;
efi_uintn_t ret;
print(u"=> ");
ret = efi_input(command, sizeof(command));
if (ret == EFI_ABORTED)
break;
pos = skip_whitespace(command);
if (starts_with(pos, u"exit"))
break;
else if (starts_with(pos, u"load "))
do_load(pos + 5);
else if (starts_with(pos, u"save "))
do_save(pos + 5);
else
do_help();
}
cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
cout->clear_screen(cout);
return EFI_SUCCESS;
}