Lenovo T60 - Intel graphics with unsupported display panel - black screen

[Łukasz Dmitrowski]

Hello,

I am trying to run coreboot with seabios payload on Lenovo T60:

Graphic: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2] (rev 03)
Display panel: LTN141XA-L01

So, graphic is Intel, but display panel LTN141XA-L01 is not supported for native
graphics initialization. I dumped VGABIOS from memory and attached it to the ROM file:

./cbfstool coreboot.rom add -f vgabios_from_mem.bin -n pci8086,27a2.rom -t raw
./cbfstool coreboot.rom add-int -i 0 -n etc/optionroms-checksum

Unfortunately after powering on - screen is black. Did I miss something?

--------------------------------

VGABIOS which I use:

Image 1:
PCI Expansion ROM Header:
   Signature: 0x55aa (Ok)
   CPU unique data: 0x75 0xe9 0xa9 0xe3 0x30 0x30 0x30 0x30
                    0x30 0x30 0x30 0x30 0x30 0x30 0x30 0x30
   Pointer to PCI Data Structure: 0x0040

PCI Data Structure:
   Signature: 0x50434952 'PCIR' (Ok)
   Vendor ID: 0x8086
   Device ID: 0x27a2
   Vital Product Data:  0x0000
   PCI Data Structure Length: 0x0018 (24 bytes)
   PCI Data Structure Revision: 0x00
   Class Code: 0x030000 (VGA Display controller)
   Image Length: 0x0080 blocks (65536 bytes)
   Revision Level of Code/Data: 0x0000
   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: 0x75 (59904 bytes)
   Entry point for INIT function: 0xe3af

-----------------------------------

ROM contents:

cmos.default                   0x0        cmos_default 256
cmos_layout.bin                0x140      cmos_layout  1824
fallback/dsdt.aml              0x8c0      raw          12037
fallback/romstage              0x3800     stage        36472
fallback/ramstage              0xc6c0     stage        53914
fallback/payload               0x199c0    payload      55825
etc/ps2-keyboard-spinup        0x27440    raw          8
config                         0x27480    raw          82
revision                       0x27500    raw          569
etc/optionroms-checksum        0x27780    raw          8
pci8086,27a2.rom               0x277c0    raw          32768
(empty)                        0x2f800    null         1901528

------------------------------------

Regards,
Lukasz Dmitrowski

[Łukasz Dmitrowski]

Problem solved after using VGABIOS extracted from factory BIOS instead of one extracted from memory.

Regards,
Lukasz Dmitrowski

On 14.08.2015 13:29, Łukasz Dmitrowski wrote:
> Hello,
>
> I am trying to run coreboot with seabios payload on Lenovo T60:
>
> Graphic: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2] (rev 03)
> Display panel: LTN141XA-L01
>
> So, graphic is Intel, but display panel LTN141XA-L01 is not supported for native
> graphics initialization. I dumped VGABIOS from memory and attached it to the ROM file:
>
> ./cbfstool coreboot.rom add -f vgabios_from_mem.bin -n pci8086,27a2.rom -t raw
> ./cbfstool coreboot.rom add-int -i 0 -n etc/optionroms-checksum
>
> Unfortunately after powering on - screen is black. Did I miss something?
>
> VGABIOS which I use:
>
> Image 1:
> PCI Expansion ROM Header:
>    Signature: 0x55aa (Ok)
>    CPU unique data: 0x75 0xe9 0xa9 0xe3 0x30 0x30 0x30 0x30
>                     0x30 0x30 0x30 0x30 0x30 0x30 0x30 0x30
>    Pointer to PCI Data Structure: 0x0040
>
> PCI Data Structure:
>    Signature: 0x50434952 'PCIR' (Ok)
>    Vendor ID: 0x8086
>    Device ID: 0x27a2
>    Vital Product Data:  0x0000
>    PCI Data Structure Length: 0x0018 (24 bytes)
>    PCI Data Structure Revision: 0x00
>    Class Code: 0x030000 (VGA Display controller)
>    Image Length: 0x0080 blocks (65536 bytes)
>    Revision Level of Code/Data: 0x0000
>    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: 0x75 (59904 bytes)
>    Entry point for INIT function: 0xe3af
>
> ROM contents:
>
> cmos.default                   0x0        cmos_default 256
> cmos_layout.bin                0x140      cmos_layout  1824
> fallback/dsdt.aml              0x8c0      raw          12037
> fallback/romstage              0x3800     stage        36472
> fallback/ramstage              0xc6c0     stage        53914
> fallback/payload               0x199c0    payload      55825
> etc/ps2-keyboard-spinup        0x27440    raw          8
> config                         0x27480    raw          82
> revision                       0x27500    raw          569
> etc/optionroms-checksum        0x27780    raw          8
> pci8086,27a2.rom               0x277c0    raw          32768
> (empty)                        0x2f800    null         1901528
>
> Regards,
> Lukasz Dmitrowski

Hi Lukasz,

maybe there is a way to run coreboot (coreboot-libre) without the
VGABIOS blob on your T60.

You may check if you are running coreboot with dual channel LVDS mode
enforced (register "gfx.lvds_dual_channel" = "1").

If this is true, changing to single channel LVDS mode (register
"gfx.lvds_dual_channel" = "0") may result in native graphics
initialization.

This would be the inversely workaround for a T400 with a
"high-resolution" display [1 [1]].

Best Regards,

Kroms

[1] http://libreboot.org/docs/hcl/gm45_lcd.html

Am 14.08.2015 15:08 schrieb Łukasz Dmitrowski:
> Problem solved after using VGABIOS extracted from factory BIOS instead
> of one extracted from memory.
>
> Regards,
> Lukasz Dmitrowski
>
> On 14.08.2015 13:29, Łukasz Dmitrowski wrote:
> > Hello,
> >
> > I am trying to run coreboot with seabios payload on Lenovo T60:
> >
> > Graphic: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller [8086:27a2] (rev 03)
> > Display panel: LTN141XA-L01
> >
> > So, graphic is Intel, but display panel LTN141XA-L01 is not supported for native
> > graphics initialization. I dumped VGABIOS from memory and attached it to the ROM file:
> >
> > ./cbfstool coreboot.rom add -f vgabios_from_mem.bin -n pci8086,27a2.rom -t raw
> > ./cbfstool coreboot.rom add-int -i 0 -n etc/optionroms-checksum
> >
> > Unfortunately after powering on - screen is black. Did I miss something?
> >
> > VGABIOS which I use:
> >
> > Image 1:
> > PCI Expansion ROM Header:
> > Signature: 0x55aa (Ok)
> > CPU unique data: 0x75 0xe9 0xa9 0xe3 0x30 0x30 0x30 0x30
> > 0x30 0x30 0x30 0x30 0x30 0x30 0x30 0x30
> > Pointer to PCI Data Structure: 0x0040
> >
> > PCI Data Structure:
> > Signature: 0x50434952 'PCIR' (Ok)
> > Vendor ID: 0x8086
> > Device ID: 0x27a2
> > Vital Product Data: 0x0000
> > PCI Data Structure Length: 0x0018 (24 bytes)
> > PCI Data Structure Revision: 0x00
> > Class Code: 0x030000 (VGA Display controller)
> > Image Length: 0x0080 blocks (65536 bytes)
> > Revision Level of Code/Data: 0x0000
> > 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: 0x75 (59904 bytes)
> > Entry point for INIT function: 0xe3af
> >
> > ROM contents:
> >
> > cmos.default 0x0 cmos_default 256
> > cmos_layout.bin 0x140 cmos_layout 1824
> > fallback/dsdt.aml 0x8c0 raw 12037
> > fallback/romstage 0x3800 stage 36472
> > fallback/ramstage 0xc6c0 stage 53914
> > fallback/payload 0x199c0 payload 55825
> > etc/ps2-keyboard-spinup 0x27440 raw 8
> > config 0x27480 raw 82
> > revision 0x27500 raw 569
> > etc/optionroms-checksum 0x27780 raw 8
> > pci8086,27a2.rom 0x277c0 raw 32768
> > (empty) 0x2f800 null 1901528
> >
> > Regards,
> > Lukasz Dmitrowski

Links:
------
[1] http://libreboot.org/docs/hcl/gm45_lcd.html