Changes for complying to EFI spec ยง3.5.1.1
'Removable Media Boot Behavior'.
Boot variables can be automatically generated during a removable
media is probed. At the same time, unused boot variables will be
detected and removed.

Please note that currently the function 'efi_disk_remove' has no
ability to distinguish below two scenarios
a) Unplugging of a removable media under U-Boot
b) U-Boot existing and booting an OS
Thus currently the boot variables management is not added into
'efi_disk_remove' to avoid boot options being added/erased
repeatedly under scenario b) during power cycles
See TODO comments under function 'efi_disk_remove' for more details

Signed-off-by: Raymond Mao <raymond....@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.g...@gmx.de>
Reviewed-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
---
Changes in v3
- Split the patch into moving and renaming functions and
  individual patches for each changed functionality
Changes in v5
- Move function call of efi_bootmgr_update_media_device_boot_option()
  from efi_init_variables() to efi_init_obj_list()
Changes in v6
- Revert unrelated changes
Changes in v7
- adapt the return code of function
  efi_bootmgr_update_media_device_boot_option()
Changes in v8
- add a note in the commit message for future reference
Changes in v9
- amend the note text in the commit message
- add a TODO comment in 'efi_disk_remove'

 lib/efi_loader/efi_disk.c  | 18 ++++++++++++++++++
 lib/efi_loader/efi_setup.c |  5 +++++
 2 files changed, 23 insertions(+)

diff --git a/lib/efi_loader/efi_disk.c b/lib/efi_loader/efi_disk.c
index d2256713a8..8ccf3dd158 100644
--- a/lib/efi_loader/efi_disk.c
+++ b/lib/efi_loader/efi_disk.c
@@ -687,6 +687,13 @@ int efi_disk_probe(void *ctx, struct event *event)
                        return -1;
        }
 
+       /* only do the boot option management when UEFI sub-system is 
initialized */
+       if (efi_obj_list_initialized == EFI_SUCCESS) {
+               ret = efi_bootmgr_update_media_device_boot_option();
+               if (ret != EFI_SUCCESS)
+                       return -1;
+       }
+
        return 0;
 }
 
@@ -773,6 +780,17 @@ int efi_disk_remove(void *ctx, struct event *event)
                return efi_disk_delete_part(dev);
        else
                return 0;
+
+       /*
+        * TODO A flag to distinguish below 2 different scenarios of this
+        * function call is needed:
+        * a) Unplugging of a removable media under U-Boot
+        * b) U-Boot existing and booting an OS
+        * In case of scenario a), efi_bootmgr_update_media_device_boot_option()
+        * needs to be invoked here to update the boot options and remove the
+        * unnecessary ones.
+        */
+
 }
 
 /**
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index 58d4e13402..877f3878d6 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -245,6 +245,11 @@ efi_status_t efi_init_obj_list(void)
        if (ret != EFI_SUCCESS)
                goto out;
 
+       /* update boot option after variable service initialized */
+       ret = efi_bootmgr_update_media_device_boot_option();
+       if (ret != EFI_SUCCESS)
+               goto out;
+
        /* Define supported languages */
        ret = efi_init_platform_lang();
        if (ret != EFI_SUCCESS)
-- 
2.25.1

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