[coreboot] T60 with ATI has black screen

[Carl-Daniel Hailfinger]

On 27.06.2015 23:39, Richard Simpson wrote:
> Hello,
>
> I have finally successfully flashed the BIOS on my T60 with coreboot.
> Sadly, my ATI controlled screen remains completely black.  Fortunately I
> can still get in via ssh.  Here is what I can deduce so far.+

AFAICS you have exactly the same T60 as I have.


> lspci says:
> 01:00.0 0300: 1002:7145 (prog-if 00 [VGA controller])
>         Subsystem: 1002:0000
>         Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop-
> ParErr- Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0, Cache Line Size: 64 bytes
>         Interrupt: pin A routed to IRQ 16
>         Region 0: Memory at e0000000 (32-bit, prefetchable) [size=128M]
>         Region 1: I/O ports at 4000 [size=256]
>         Region 2: Memory at ec120000 (32-bit, non-prefetchable) [size=64K]
>         Expansion ROM at ec100000 [disabled] [size=128K]
>         Capabilities: <access denied>
>         Kernel driver in use: radeon
>
> The vgabios which I extracted from the factory bios

Ah yes. Bad idea. AFAIK the factory BIOS patches the VGA optionrom at
runtime with the correct values for the LVDS panel. This means you
either have to patch the VGA optionrom yourself or you have to extract
the VGA optionrom from the memory of the running system. If you extract
it from memory, please note that the runtime patching causes the
checksum to be incorrect, and you either have to fix the checksum or
tell SeaBIOS to ignore the checksum.


> reports as follows:
>
> Image 1:
> PCI Expansion ROM Header:
>   Signature: 0x55aa (Ok)
>   CPU unique data: 0x7e 0xe9 0x6f 0x02 0x00 0x00 0x00 0x00
>                    0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
>   Pointer to PCI Data Structure: 0x0230
>
> PCI Data Structure:
>   Signature: 0x50434952 'PCIR' (Ok)
>   Vendor ID: 0x1002
>   Device ID: 0x7145
>   Vital Product Data:  0x0000
>   PCI Data Structure Length: 0x0018 (24 bytes)
>   PCI Data Structure Revision: 0x00
>   Class Code: 0x030000 (VGA Display controller)
>   Image Length: 0x007e blocks (64512 bytes)
>   Revision Level of Code/Data: 0x090c
>   Code Type: 0x00 (Intel x86)
>   Last-Image Flag: 0x80 (last image in rom)
>   Reserved: 0x0000
>
> Platform specific data for x86 compliant option rom:
>   Initialization Size: 0x7e (64512 bytes)
>   Entry point for INIT function: 0x275
>
> This looks like the right VGA BIOS to me.
>
> Once I have added it to the coreboot image I can check the contents as
> follows:
>
> coreboot.rom: 2048 kB, bootblocksize 952, romsize 2097152, offset 0x0
> alignment: 64 bytes, architecture: x86
>
> Name                           Offset     Type         Size
> cmos.default                   0x0        cmos_default 256
> cmos_layout.bin                0x140      cmos_layout  1824
> fallback/dsdt.aml              0x8c0      raw          12037
> cpu_microcode_blob.bin         0x3800     microcode    94208
> etc/ps2-keyboard-spinup        0x1a880    raw          8
> config                         0x1a8c0    raw          4046
> revision                       0x1b8c0    raw          571
> (empty)                        0x1bb40    null         17432
> fallback/romstage              0x1ff80    stage        36524
> fallback/ramstage              0x28ec0    stage        53635
> fallback/payload               0x36080    payload      55837
> pci1002,7145.rom               0x43b00    raw          64512
> (empty)                        0x53740    null         1754264
>
> I would be most grateful for any suggestions as to where I might be
> going wring or further diagnostics.

On the first coreboot try I had a black screen as well on my T60 (ATI
graphics). Funnily enough, the external VGA worked. Could you check if
that's the case for you?

Regards,
Carl-Daniel