lib/efi_loader/gbl_efi_boot_control.c

/*
 * Copyright (c) 2026 The Fuchsia Authors
 *
 * SPDX-License-Identifier:	BSD-3-Clause
 */

#include <common.h>
#include <efi_loader.h>
#include <gbl_efi_boot_control_protocol.h>

// Slot management functions return EFI_UNSUPPORTED as GBL's Fuchsia flow
// does not rely on this protocol for slot work.

static efi_status_t EFIAPI
get_slot_count(struct GblEfiBootControlProtocol *self, uint8_t *slot_count)
{
	EFI_ENTRY("%p, %p", self, slot_count);
	return EFI_EXIT(EFI_UNSUPPORTED);
}

static efi_status_t EFIAPI get_slot_info(struct GblEfiBootControlProtocol *self,
					 uint8_t index, GblEfiSlotInfo *info)
{
	EFI_ENTRY("%p, %d, %p", self, index, info);
	return EFI_EXIT(EFI_UNSUPPORTED);
}

static efi_status_t EFIAPI
get_current_slot(struct GblEfiBootControlProtocol *self, GblEfiSlotInfo *info)
{
	EFI_ENTRY("%p, %p", self, info);
	return EFI_EXIT(EFI_UNSUPPORTED);
}

static efi_status_t EFIAPI
set_active_slot(struct GblEfiBootControlProtocol *self, uint8_t index)
{
	EFI_ENTRY("%p, %d", self, index);
	return EFI_EXIT(EFI_UNSUPPORTED);
}

static efi_status_t EFIAPI get_one_shot_boot_mode(
	struct GblEfiBootControlProtocol *self, GblEfiOneShotBootMode *mode)
{
	EFI_ENTRY("%p, %p", self, mode);
	if (!mode)
		return EFI_EXIT(EFI_INVALID_PARAMETER);

	char *boot_mode = getenv("gbl_one_shot_boot_mode");

	if (boot_mode && (strcmp(boot_mode, "bootloader") == 0 ||
			  strcmp(boot_mode, "fastboot") == 0)) {
		printf("GBL: One-shot boot mode set via env: %s\n", boot_mode);
		*mode = GBL_EFI_ONE_SHOT_BOOT_MODE_BOOTLOADER;
		return EFI_EXIT(EFI_SUCCESS);
	}

	printf("\nPress 'f' to enter fastboot mode...\n");
	ulong start = get_timer(0);
	bool enter_fastboot = false;
	while (get_timer(start) < 2000) {
		if (tstc()) {
			int c = getc();
			if (c == 'f') {
				enter_fastboot = true;
				break;
			}
		}
		udelay(1000);
	}

	if (enter_fastboot) {
		printf("Entering fastboot mode...\n");
		*mode = GBL_EFI_ONE_SHOT_BOOT_MODE_BOOTLOADER;
	} else {
		*mode = GBL_EFI_ONE_SHOT_BOOT_MODE_NONE;
	}
	return EFI_EXIT(EFI_SUCCESS);
}

static efi_status_t EFIAPI handle_loaded_os(
	struct GblEfiBootControlProtocol *self, const GblEfiLoadedOs *os)
{
	EFI_ENTRY("%p, %p", self, os);
	if (!os)
		return EFI_EXIT(EFI_INVALID_PARAMETER);

	printf("GBL: Loaded OS: kernel size %zu at 0x%llx, ramdisk size %zu at 0x%llx\n",
	       os->kernel_size, os->kernel, os->ramdisk_size, os->ramdisk);
	return EFI_EXIT(EFI_SUCCESS);
}

static const efi_guid_t guid = EFI_GUID(0xd382db1b, 0x9ac2, 0x11f0, 0x84, 0xc7,
					0x04, 0x7b, 0xcb, 0xa9, 0x60, 0x19);

static GblEfiBootControlProtocol protocol = {
	.revision = GBL_EFI_BOOT_CONTROL_PROTOCOL_REVISION,
	.get_slot_count = get_slot_count,
	.get_slot_info = get_slot_info,
	.get_current_slot = get_current_slot,
	.set_active_slot = set_active_slot,
	.get_one_shot_boot_mode = get_one_shot_boot_mode,
	.handle_loaded_os = handle_loaded_os,
};

efi_status_t efi_gbl_boot_control_register(void)
{
	efi_status_t ret = efi_add_protocol(efi_root, &guid, (void *)&protocol);
	if (ret != EFI_SUCCESS)
		printf("Cannot install GBL_EFI_BOOT_CONTROL_PROTOCOL\n");
	return ret;
}