Project

General

Profile

Actions

Bug #32

closed

[Haswell/Broadwell] LPC power optimizer RCBA instructions break eDP display with Intel VBIOS

Added by CoolStar Organization almost 9 years ago. Updated about 8 years ago.

Status:
Closed
Priority:
Normal
Assignee:
-
Category:
-
Target version:
-
Start date:
02/06/2016
Due date:
% Done:

0%

Estimated time:
Affected versions:
Needs backport to:
Affected hardware:
Affected OS:

Description

With the Intel VBIOS other than version 2070 run by SeaBIOS, or with Windows's Intel HD Graphics driver, an LPC power optimizer setting breaks eDP on Haswell/Broadwell.

Affected Haswell code: https://github.com/coreboot/coreboot/blob/master/src/southbridge/intel/lynxpoint/lpc.c#L349
Affected Broadwell code: https://github.com/coreboot/coreboot/blob/master/src/soc/intel/broadwell/lpc.c#L285

Removing the power optimizer lines fixes eDP display on Haswell/Broadwell.

Actions #1

Updated by CoolStar Organization over 8 years ago

Also, with the Tianocore payload, the Intel GOP driver is affected by the same issue with eDP. The same patch also fixes the issue with the UEFI GOP driver.

Actions #3

Updated by Martin Roth about 8 years ago

  • Status changed from New to Closed

Patch is merged. Closing the issue.

Actions

Also available in: Atom PDF