[3.4.0.24] [Xperia 10] Screen goes blank when decrypting user data during boot

Bug Reports
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#1

REPRODUCIBILITY (% or how often): 100% (always)
BUILD ID = OS VERSION (Settings > About product): Build 3.4.0.24, Device adaptation 0.0.4.10
HARDWARE (Jolla1, Tablet, XA2,…): Xperia 10 Single Sim
UI LANGUAGE: English (US)
REGRESSION: (compared to previous public release: Yes, No, ?): idk, i just got this phone and 3.4.0 is the first build i try on it.

DESCRIPTION:

The display goes blank during boot before and after entering the pin to decryption the phone. it seems like this bug from the previous build (that is deleted in known issue for 10 in 3.4.0) is still existing on 3.4.0.24:

  • During the decryption of user data in device start-up, there is a period of 10-20 seconds such that the display is black

PRECONDITIONS:

Reboot or cold start

STEPS TO REPRODUCE:

  1. reboot the phone or start the device after power off
  2. Sony logo appear
  3. screen goes blank for a while
  4. The pin code field appear for you to enter the pin code to decrypt the device
  5. The screen goes blank for a while again
  6. The lock screen appears

EXPECTED RESULT:

The phone should go directly from step 2 to 4 and 4 to 6, skipping step 3 and 5.

ACTUAL RESULT:

The screen goes blank as described in step 3 and 5

ADDITIONAL INFORMATION:

Here is the link to the video of showing the bug: https://1drv.ms/v/s!AjJ0jXrlCoD0i_Na7bzIlYJsMJjxnw?e=fO5NMw

1 Like
#2

What would you expect to see if not a blank screen?
I mean ther is not really anything to show there, right?

2 Likes
#3

The idea is to minimize display blank time when switching from boot logo to unlock prompt and from unlock prompt to regular sailfish ui managed by lipstick. While there is some variance between devices in how it actually goes, generally speaking in devices with fbdev kernel unlock prompt stays on screen and that animated spinner is shown all the way until lockscreen appears.

In case of Xperia 10 there is some blank time due to combination of: lipstick uses android hw compositor for display control (performance) while unlock needs to use kernel interfaces directly (minimal dependencies), how android service bring up happens during bootup and how drm/kms kernel works -> hw compositor needs to be stopped before unlock prompt can be shown (= blank gap at step 3) and started again in between unlock prompt and lipstick startup (= blank gap at step 5).

3 Likes