Xorg , nv driver and mtrr

[nk_bg]

After bootup, i have this in /proc/mtrr:

reg00: base=0xe0000000 (3584MB), size= 32MB: write-combining, count=1

this is the base and the amount of memory of my card (PCI TNT2 M64)

But when i look in lspci -v:

Memory at e2000000 (32-bit, non-prefetchable) [size=16M]
Memory at e0000000 (32-bit, prefetchable) [size=32M]

What is that "second" memory with size 16 MB and base addr at e2000000 ?
Should i give it a MTRR register manually ?

The Xorg.0.log says something about MMIO registers at this base address.

Please clarify, thanks

[gilboa]

Can you post the full lspci -vv?

Cheers,
Gilboa

[nk_bg]

Originally Posted by gilboa

Can you post the full lspci -vv?

Cheers,
Gilboa

00:11.0 VGA compatible controller: nVidia Corporation NV5M64 [RIVA TNT2 Model 64/Model 64 Pro] (rev 15) (prog-if 00 [VGA])
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B-
Status: Cap+ 66Mhz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR-
Latency: 32 (1250ns min, 250ns max)
Interrupt: pin A routed to IRQ 9
Region 0: Memory at e2000000 (32-bit, non-prefetchable) [size=16M]
Region 1: Memory at e0000000 (32-bit, prefetchable) [size=32M]
Expansion ROM at <unassigned> [disabled] [size=64K]
Capabilities: [60] Power Management version 1
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
Status: D0 PME-Enable- DSel=0 DScale=0 PME-

[Pinky's brain]

I have the same on my TNT and it works fine (well at least with 2.4 kernels, with 2.6 release kernels the Expansion ROM line dissappears and the card gets dog slow ... and in the 2.6 snapshots the two memory regions get disabled altogether, making it impossible for X to use).

Your guess is right I think, it is a region used for I/O and it should be uncacheable.

[gilboa]

Execute this:
$ echo 'disable=00' > /proc/mtrr
$ echo 'disable=01' > /proc/mtrr
$ echo 'disable=02' > /proc/mtrr
$ echo "base=0xe2000000 size=0x01000000 type=write-combining" >/proc/mtrr
$ echo "base=0xe0000000 size=0x02000000 type=write-combining" >/proc/mtrr


Now try running X.

[nk_bg]

Originally Posted by gilboa

Execute this:
$ echo 'disable=00' > /proc/mtrr
$ echo 'disable=01' > /proc/mtrr
$ echo 'disable=02' > /proc/mtrr
$ echo "base=0xe2000000 size=0x01000000 type=write-combining" >/proc/mtrr
$ echo "base=0xe0000000 size=0x02000000 type=write-combining" >/proc/mtrr


Now try running X.

OK, i've stopped X, (telinit 3), executed those commands, and i got two regions with mtrr registers in /proc/mtrr
After running X, it's just one region again.
Maybe i will ask in the Xorg forum for this issue.

[gilboa]

Wierd...

Check the dmesg after you try running X... maybe we'll get something useful...