efi_loader: Disable devices before handing over control

U-Boot Driver Model is supposed to remove devices with either
DM_REMOVE_ACTIVE_DMA or DM_REMOVE_OS_PREPARE flags set, before exiting.
Our bootm command does that by explicitly calling calling
"dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);" and we also disable any
USB devices.

The EFI equivalent is doing none of those at the moment. As a result
probing an fTPM driver now renders it unusable in Linux. During our
(*probe) callback we open a session with OP-TEE, which is supposed to
close with our (*remove) callback. Since the (*remove) is never called,
once we boot into Linux and try to probe the device again we are getting
a busy error response. Moreover all uclass (*preremove) functions won't
run.

So let's fix this by mimicking what bootm does and disconnect devices
when efi_exit_boot_services() is called.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Ilias Apalodimas 2020-10-22 01:04:21 +03:00 committed by Heinrich Schuchardt
parent 19763ea0d2
commit 529441ca89

View file

@ -8,6 +8,8 @@
#include <common.h>
#include <bootm.h>
#include <div64.h>
#include <dm/device.h>
#include <dm/root.h>
#include <efi_loader.h>
#include <irq_func.h>
#include <log.h>
@ -15,6 +17,7 @@
#include <pe.h>
#include <time.h>
#include <u-boot/crc.h>
#include <usb.h>
#include <watchdog.h>
#include <linux/libfdt_env.h>
@ -1993,7 +1996,10 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
list_del(&evt->link);
}
if IS_ENABLED(CONFIG_USB_DEVICE)
udc_disconnect();
board_quiesce_devices();
dm_remove_devices_flags(DM_REMOVE_ACTIVE_ALL);
/* Patch out unsupported runtime function */
efi_runtime_detach();