Re: i915 observations

[RVP <rvp%SDF.ORG@localhost>]

On Sun, 18 Dec 2022, Ron Georgia wrote:

> All configurations were a bust. Then I copied all linux-firmware/intel to 
> /libdata/firmware/intel/

That is the wrong directory, I think, so very likely those firmware blobs
aren't being picked up.

> My Device section of my xorg.conf looks like this:
>
>  Section "Device"
>      Option     "Accel"          "True"

You don't need this--it's the default.

>      BusID       "PCI:0:2:0"

Also not needed. The Xorg server will almost always correctly figure this
out. (BusID is really only useful when you have multiple graphics cards.)

>  EndSection
>
> Everything works! Well, the response is a little sluggish and firefox takes 
> forever to load, but the video is solid.
>
> I do have a lot of "heartbeat" messages in dmesg. I also see this with dmesg:
>
> [  1633.783213] heartbeat     On hold?: 0
> [  1633.783213] heartbeat     MMIO base:  0x00002000
> [  1633.783213] heartbeat     CCID: 0x01b5610d
> [  1633.783213] heartbeat     RING_START: 0x7fffb000
> [  1633.783213] heartbeat     RING_HEAD:  0x00000798
> [  1633.783213] heartbeat     RING_TAIL:  0x00000bb0
> [  1633.783213] heartbeat     RING_CTL:   0x00003001
> [  1633.783213] heartbeat     RING_MODE:  0x00004000
> [  1633.783213] heartbeat     RING_IMR: fffffffe
> [  1633.783213] heartbeat     ACTHD:  0x00000000_01b0731c
> [  1633.783213] heartbeat     BBADDR: 0x00000000_01b0731d
> [  1633.783213] heartbeat     DMA_FADDR: 0x00000000_01b07500
> [  1633.783213] heartbeat     IPEIR: 0x00000000
> [  1633.783213] heartbeat     IPEHR: 0x7a000003
> [  1633.783213] heartbeat     PP_DIR_BASE: 0x02210000
> [  1633.783213] heartbeat     PP_DIR_BASE_READ: 0x00000000
> [  1633.783213] heartbeat     PP_DIR_DCLV: 0xffffffff
> [  1633.783213] heartbeat         E  2:350a5*-  @ 5950ms: firefox[13741]
> [  1633.783213] heartbeat         E  2:350a6-  @ 5940ms: X[1020]
> [  1633.783213] heartbeat         E  2:350a7  @ 5920ms: firefox[13741]
> [  1633.783213] heartbeat         E  2:350a8  @ 5920ms: X[1020]
> [  1633.783213] heartbeat         E  2:350a9  @ 5920ms: X[1020]
> [  1633.783213] heartbeat         E  2:350aa  @ 3000ms: [i915][  1633.783213] 
> heartbeat *
>
> [  1633.783213] heartbeat Idle? no
> [  1633.783213] heartbeat Signals:
> [  1633.783213] heartbeat     [2:350a5*] @ 5950ms
> [  1633.783213] heartbeat     [2:350a6] @ 5940ms
> [  1633.783213] i915drmkms0: notice: Resetting chip for stopped heartbeat on 
> rcs0
> [  1633.783213] i915drmkms0: notice: firefox[13741] context reset due to GPU 
> hang

Yeah. those heartbeat messages triggered by GPU hangs are what I see with
most of the standard configs. "modesetting", "intel", "intel" + "UXA"
all lock-up the Xorg process. With both "modesetting" and "intel" and
"AccelMethod" "none", the screen contents are extremely slow to update,
and have a very streaky look when the update is going on. What this looks
like can be seen in the video here:

http://mail-index.NetBSD.org/current-users/2022/11/10/msg043195.html

Alrighty, now for what _works_ for me (latest -HEAD):

```
$ cat /etc/X11/xorg.conf.d/display.conf
Section "Device"
    Identifier  "Card0"
    Driver      "intel"
    Option      "AccelMethod"   "blt"
    Option      "DRI"           "off"
EndSection
$
```

This is SNA + the "blt" engine, and DRI turned off. This is a step up from
`wsfb' because:

a) the system runs ~10C cooler.
b) xrandr (rotation--tested, multiple displays--can't test) works.

Hope this helps,
-RVP