On Wed, Aug 07, 2019 at 03:16:56PM +0200, Mark Kettenis wrote:
> >
> > I built a kernel with DRMDEBUG and put 0xffff in drm_debug variable.
> >
> > initializing kernel modesetting (RV610 0x1002:0x94C3 0x1028:0x0402 0x00).
> > [drm] COMBIOS detected
> > drm:pid0:r600_init *ERROR* Expecting atombios for R600 GPU
> > drm:pid0:radeondrm_attachhook *ERROR* Fatal error during GPU init
> > [drm] radeon: finishing device.
> > [TTM] Memory type 2 has not been initialized
> > [drm]
> > drm0 detached
> > radeondrm0 detached
> > vga1 at pci1 dev 0 function 0 "ATI Radeon HD 2400 Pro" rev 0x00
> >
> >
> > I tried to follow a bit the initialisation path from radeon_get_bios():
> > - radeon_get_bios()
> > - radeon_read_disabled_bios()
> > - r600_read_disabled_bios()
> > - init registers
> > - radeon_read_bios()
> > - restore registers
>
> Can you try to figure out where exactly reading the BIOS from the card
> goes wrong?
radeon_read_bios (called by r600_read_disabled_bios) returns something
good enough to pass some tests (bios signature check) and finally
returns true. the fail is later (in r600_init function, where it checks
for ATOM bios. it isn't so its abort init).
so I tried something stupid: commenting the call to
radeon_read_disabled_bios, in order to force radeon_get_bios to try
another way to get bios.
it called radeon_read_platform_bios() (the next method) and succeed. it
returned an ATOM bios (so r600_init is happy), radeondrm(4) finished its
initialization, and xenodm started correctly.
$ dmesg
...
initializing kernel modesetting (RV610 0x1002:0x94C3 0x1028:0x0402
0x00).
radeondrm0: 1680x1050, 32bpp
wsdisplay0 at radeondrm0 mux 1: console (std, vt100 emulation), using
wskbd0
...
$ xrandr
<
Screen 0: minimum 320 x 200, current 1680 x 1050, maximum 8192 x 8192
DIN disconnected primary (normal left inverted right x axis y axis)
DVI-0 connected 1680x1050+0+0 (normal left inverted right x axis y
axis) 430mm x 270mm
1680x1050 59.88*+
1280x1024 75.02 60.02
1152x864 75.00
1024x768 75.03 60.00
800x600 75.00 60.32
640x480 75.00 59.94
720x400 70.08
Below the patch for what I did (it could be more evident than my explain)
Index: radeon_bios.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/drm/radeon/radeon_bios.c,v
retrieving revision 1.15
diff -u -p -r1.15 radeon_bios.c
--- radeon_bios.c 14 Apr 2019 10:14:54 -0000 1.15
+++ radeon_bios.c 7 Aug 2019 17:41:42 -0000
@@ -815,8 +815,10 @@ bool radeon_get_bios(struct radeon_devic
r = igp_read_bios_from_vram(rdev);
if (r == false)
r = radeon_read_bios(rdev);
+#if 0
if (r == false)
r = radeon_read_disabled_bios(rdev);
+#endif
if (r == false)
r = radeon_read_platform_bios(rdev);
if (r == false || rdev->bios == NULL) {
Now, I know it is only a workaround on this specific machine.
I still dunno if:
- radeon_read_disabled_bios() should return false (because it
isn't the right way for this specific card), and so the use of
radeon_read_platform_bios() is the right thing to do.
- radeon_read_disabled_bios() should return true and an ATOM bios,
and calling radeon_read_platform_bios() is a workaround.
Thanks.
--
Sebastien Marie
