blob: d90e3eb7685b52f4bb360709a2c8b91a0601671f [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 <common.h>
#include <efi_api.h>
#define BUFFER_SIZE 64
#define ESC 0x17
#define DEFAULT_FILENAME L"dtb.dtb"
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;
/**
* 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] = L" ";
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 */
cout->output_string(cout, L"\nAborted\n");
return EFI_ABORTED;
default:
break;
}
switch (key.unicode_char) {
case 0x08: /* Backspace */
if (pos) {
buffer[pos--] = 0;
cout->output_string(cout, L"\b \b");
}
break;
case 0x0a: /* Linefeed */
case 0x0d: /* Carriage return */
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;
cout->output_string(cout, 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;
}
/**
* efi_main() - entry point of the EFI application.
*
* @handle: handle of the loaded image
* @systable: system table
* @return: status code
*/
efi_status_t EFIAPI efi_main(efi_handle_t handle,
struct efi_system_table *systable)
{
efi_uintn_t ret;
u16 filename[BUFFER_SIZE] = {0};
efi_uintn_t dtb_size;
struct efi_loaded_image *loaded_image;
struct efi_simple_file_system_protocol *file_system;
struct efi_file_handle *root, *file;
struct fdt_header *dtb;
cerr = systable->std_err;
cout = systable->con_out;
cin = systable->con_in;
bs = systable->boottime;
cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
cout->clear_screen(cout);
cout->set_attribute(cout, EFI_YELLOW | EFI_BACKGROUND_BLACK);
cout->output_string(cout, L"DTB Dump\n\n");
cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
dtb = get_dtb(systable);
if (!dtb) {
cerr->output_string(cout, L"DTB not found\n");
return EFI_NOT_FOUND;
}
if (f2h(dtb->magic) != FDT_MAGIC) {
cerr->output_string(cout, L"Wrong device tree magic\n");
return EFI_NOT_FOUND;
}
dtb_size = f2h(dtb->totalsize);
cout->output_string(cout, L"Filename (" DEFAULT_FILENAME ")?\n");
ret = efi_input(filename, sizeof(filename));
if (ret != EFI_SUCCESS)
return ret;
if (!*filename)
memcpy(filename, DEFAULT_FILENAME, sizeof(DEFAULT_FILENAME));
cout->output_string(cout, L"\n");
ret = bs->open_protocol(handle, &loaded_image_guid,
(void **)&loaded_image, NULL, NULL,
EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (ret != EFI_SUCCESS) {
cerr->output_string(cout,
L"Loaded image protocol not found\n");
return ret;
}
/* Open the simple file system protocol */
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) {
cerr->output_string(
cout, L"Failed to open simple file system protocol\n");
return ret;
}
/* Open volume */
ret = file_system->open_volume(file_system, &root);
if (ret != EFI_SUCCESS) {
cerr->output_string(cerr, L"Failed to open volume\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)
cerr->output_string(cerr, L"Failed to write file\n");
file->close(file);
} else {
cerr->output_string(cerr, L"Failed to open file\n");
}
root->close(root);
if (ret == EFI_SUCCESS) {
cout->output_string(cout, filename);
cout->output_string(cout, L" written\n");
}
return ret;
}