Re: drm/mgag200: Fix big-endian support

Hi

Am 26.08.26 um 17:07 schrieb Christian Zigotzky:

> Hello Thomas,
>
> Thank you for your patch. Unfortunately the card doesn't work with the 
> patched kernel.
>
> dmesg | grep -i mga
>
> [    2.307195] [drm] Initialized mgag200 1.0.0 for 0001:05:00.0 on 
> minor 1
> [    2.308649] mgag200 0001:05:00.0: [drm] Cannot find any crtc or sizes
> [    2.309551] mgag200 0001:05:04.0: Invalid PCI ROM header signature: 
> expecting 0xaa55, got 0xffff
> [    2.310305] [drm] Initialized mgag200 1.0.0 for 0001:05:04.0 on 
> minor 2
> [    2.312660] mgag200 0001:05:04.0: [drm] Cannot find any crtc or sizes
> [    2.313177] mgag200 0001:05:00.0: [drm] Cannot find any crtc or sizes
> [    2.313640] mgag200 0001:05:08.0: Invalid PCI ROM header signature: 
> expecting 0xaa55, got 0xffff
> [    2.314357] [drm] Initialized mgag200 1.0.0 for 0001:05:08.0 on 
> minor 3
> [    2.317630] mgag200 0001:05:08.0: [drm] Cannot find any crtc or sizes
> [    2.318185] mgag200 0001:05:0c.0: Invalid PCI ROM header signature: 
> expecting 0xaa55, got 0xffff
> [    2.318840] mgag200 0001:05:04.0: [drm] Cannot find any crtc or sizes
> [    2.319345] [drm] Initialized mgag200 1.0.0 for 0001:05:0c.0 on 
> minor 4
> [    2.321014] mgag200 0001:05:0c.0: [drm] Cannot find any crtc or sizes
> [    2.322400] mgag200 0001:05:08.0: [drm] Cannot find any crtc or sizes
> [    2.327215] mgag200 0001:05:0c.0: [drm] Cannot find any crtc or sizes
>
> lspci -vvv
>
> 0001:05:00.0 VGA compatible controller: Matrox Electronics Systems 
> Ltd. MGA G200 AGP (rev 03) (prog-if 00 [VGA controller])
>     Subsystem: Matrox Electronics Systems Ltd. G200 Multi-Monitor
>     Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
> ParErr- Stepping- SERR- FastB2B- DisINTx-
>     Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- 
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>     Latency: 128 (4000ns min, 8000ns max), Cache Line Size: 32 bytes
>     Interrupt: pin A routed to IRQ 18
>     Region 0: Memory at c20000000 (32-bit, prefetchable) [size=16M]
>     Region 1: Memory at c21000000 (32-bit, non-prefetchable) [size=16K]
>     Region 2: Memory at c21800000 (32-bit, non-prefetchable) [size=8M]
>     Expansion ROM at c21010000 [disabled] [size=64K]

Could be that we have to enable access to the ROM first. That's why it 
returns only 0xffff. Does the card display output when you switch on the 
computer?

Best regards
Thomas


> Capabilities: [dc] Power Management version 1
>         Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA 
> PME(D0-,D1-,D2-,D3hot-,D3cold-)
>         Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>     Capabilities: [f0] AGP version 1.0
>         Status: RQ=32 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 
> 64bit- FW- AGP3- Rate=x1,x2
>         Command: RQ=1 ArqSz=0 Cal=0 SBA- AGP- GART64- 64bit- FW- 
> Rate=<none>
>     Kernel driver in use: mgag200
>
> 0001:05:04.0 Display controller: Matrox Electronics Systems Ltd. MGA 
> G200 AGP (rev 03)
>     Subsystem: Matrox Electronics Systems Ltd. G200 Multi-Monitor
>     Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
> ParErr- Stepping- SERR- FastB2B- DisINTx-
>     Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- 
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>     Latency: 128 (4000ns min, 8000ns max), Cache Line Size: 32 bytes
>     Interrupt: pin A routed to IRQ 18
>     Region 0: Memory at c22000000 (32-bit, prefetchable) [size=16M]
>     Region 1: Memory at c23000000 (32-bit, non-prefetchable) [size=16K]
>     Region 2: Memory at c23800000 (32-bit, non-prefetchable) [size=8M]
>     Expansion ROM at c21020000 [disabled] [size=64K]
>     Capabilities: [dc] Power Management version 1
>         Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA 
> PME(D0-,D1-,D2-,D3hot-,D3cold-)
>         Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>     Capabilities: [f0] AGP version 1.0
>         Status: RQ=32 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 
> 64bit- FW- AGP3- Rate=x1,x2
>         Command: RQ=1 ArqSz=0 Cal=0 SBA- AGP- GART64- 64bit- FW- 
> Rate=<none>
>     Kernel driver in use: mgag200
>
> 0001:05:08.0 Display controller: Matrox Electronics Systems Ltd. MGA 
> G200 AGP (rev 03)
>     Subsystem: Matrox Electronics Systems Ltd. G200 Multi-Monitor
>     Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
> ParErr- Stepping- SERR- FastB2B- DisINTx-
>     Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- 
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>     Latency: 128 (4000ns min, 8000ns max), Cache Line Size: 32 bytes
>     Interrupt: pin A routed to IRQ 18
>     Region 0: Memory at c24000000 (32-bit, prefetchable) [size=16M]
>     Region 1: Memory at c25000000 (32-bit, non-prefetchable) [size=16K]
>     Region 2: Memory at c25800000 (32-bit, non-prefetchable) [size=8M]
>     Expansion ROM at c21030000 [disabled] [size=64K]
>     Capabilities: [dc] Power Management version 1
>         Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA 
> PME(D0-,D1-,D2-,D3hot-,D3cold-)
>         Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>     Capabilities: [f0] AGP version 1.0
>         Status: RQ=32 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 
> 64bit- FW- AGP3- Rate=x1,x2
>         Command: RQ=1 ArqSz=0 Cal=0 SBA- AGP- GART64- 64bit- FW- 
> Rate=<none>
>     Kernel driver in use: mgag200
>
> 0001:05:0c.0 Display controller: Matrox Electronics Systems Ltd. MGA 
> G200 AGP (rev 03)
>     Subsystem: Matrox Electronics Systems Ltd. G200 Multi-Monitor
>     Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
> ParErr- Stepping- SERR- FastB2B- DisINTx-
>     Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- 
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>     Latency: 128 (4000ns min, 8000ns max), Cache Line Size: 32 bytes
>     Interrupt: pin A routed to IRQ 18
>     Region 0: Memory at c26000000 (32-bit, prefetchable) [size=16M]
>     Region 1: Memory at c27000000 (32-bit, non-prefetchable) [size=16K]
>     Region 2: Memory at c27800000 (32-bit, non-prefetchable) [size=8M]
>     Expansion ROM at c21040000 [disabled] [size=64K]
>     Capabilities: [dc] Power Management version 1
>         Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA 
> PME(D0-,D1-,D2-,D3hot-,D3cold-)
>         Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>     Capabilities: [f0] AGP version 1.0
>         Status: RQ=32 Iso- ArqSz=0 Cal=0 SBA+ ITACoh- GART64- HTrans- 
> 64bit- FW- AGP3- Rate=x1,x2
>         Command: RQ=1 ArqSz=0 Cal=0 SBA- AGP- GART64- 64bit- FW- 
> Rate=<none>
>     Kernel driver in use: mgag200
>
> xrandr
>
> VGA-4-4 disconnected (normal left inverted right x axis y axis)
> VGA-3-3 disconnected (normal left inverted right x axis y axis)
> VGA-2-2 disconnected (normal left inverted right x axis y axis)
> VGA-1-1 disconnected (normal left inverted right x axis y axis)
>
> lspci -nnk | grep VGA
>
> 0001:05:00.0 VGA compatible controller [0300]: Matrox Electronics 
> Systems Ltd. MGA G200 AGP [102b:0521] (rev 03)
>
> Thanks,
> Christian
>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)