Re: [9front] core-i5(TypeSNB) and vesa mode

[cinap_lenrek@felloff.net]

>> given that we do normal link training afterwards, i wonder
>> if this code is needed. i'll check what the manual says
>> on this...
>
> without that code, SNB diesn't work,
>
> Kenji

can you still try implementing it according to the documentation?
the documentation says explicitely that we have to enable FDI
with training pattern 1. and the modeset sequence gives explicit
instructions on how todo it for sandy bridge.

from https://01.org/sites/default/files/documentation/snb_ihd_os_vol3_part3.pdf
page 117 FDI_RX_CTL:

Link_training_pattern_enable 
Project: All 
Default Value:                   0b                                 
These bits are used for link initialization.  Please 
note that the link must first be configured prior to 
sending training patterns 
When enabling the port, it must be turned on with pattern 1 enabled.
When retraining, the port must be disabled, then re-enabled with
pattern 1 enabled.

modset sequence for FDI:

- Enable CPU FDI Transmitter and PCH FDI Receiver with Training Pattern 1 enabled.
- Wait for FDI training pattern 1 time
- Read PCH FDI Receiver ISR for bit lock in bit 8 (retry at least once if no lock)
- Enable training pattern 2 on CPU FDI Transmitter and PCH FDI Receiver
- Wait for FDI training pattern 2 time
- Read PCH FDI Receiver ISR for symbol lock in bit 9 (retry at least once if no lock)
- Enable normal pixel output on CPU FDI Transmitter and PCH FDI Receiver
- Wait for FDI idle pattern time for link to become active

--
cinap