No /dev/fb0 created for omapdrm in current Linux next

[Tony Lindgren]

* Tomi Valkeinen <tomi.valkeinen at ti.com> [171019 23:13]:
> On 19/10/17 19:30, Tony Lindgren wrote:
> > Hi Tomi,
> > 
> > Looks like omapdrm won't show anything with current Linux next based
> > on my test with 900:
> > 
> > modprobe twl4030_keypad
> > modprobe tsc2005
> > modprobe omapdss
> > modprobe panel_sony_acx565akm
> > modprobe omapdrm
> > 
> > echo 255 > /sys/class/backlight/acx565akm/brightness
> > echo 0 > /sys/class/graphics/fb0/blank
> > echo 1 > /sys/class/graphics/fb0/blank
> > echo 0 > /sys/class/graphics/fb0/blank
> > 
> > # ls -l /dev/fb*
> > ls: cannot access '/dev/fb*': No such file or directory

It seems to be also happening with current -rc kernels, adding Aaro
to Cc.

> What does the bootlog say?

Not much anything interesting:

twl_rtc 48070000.i2c:twl at 48:rtc: Power up reset detected.
twl_rtc 48070000.i2c:twl at 48:rtc: Enabling TWL-RTC
twl_rtc 48070000.i2c:twl at 48:rtc: rtc core: registered 48070000.i2c:twl at 48:rtc as rtc0
input: TWL4030 Keypad as /devices/platform/68000000.ocp/48070000.i2c/i2c-1/1-0048/48070000.i2c:twl at 48:keypad/input/input0
tsc2005 spi0.0: GPIO lookup for consumer reset
tsc2005 spi0.0: using device tree for GPIO lookup
of_get_named_gpiod_flags: parsed 'reset-gpios' property of node '/ocp at 68000000/spi at 48098000/tsc2005 at 0[0]' - status (0)
input: TSC2005 touchscreen as /devices/platform/68000000.ocp/48098000.spi/spi_master/spi0/spi0.0/input/input1
omapdss_dss 48050000.dss: 48050000.dss supply vdda_video not found, using dummy regulator
DSS: OMAP DSS rev 2.0
omapdss_dss 48050000.dss: bound 48050400.dispc (ops dispc_component_ops [omapdss])
omapdss_dss 48050000.dss: bound 48050c00.encoder (ops venc_component_ops [omapdss])
of_get_named_gpiod_flags: parsed 'reset-gpios' property of node '/ocp at 68000000/spi at 48098000/acx565akm at 2[0]' - status (0)
acx565akm spi0.2: omapfb: acx565akm rev 8b LCD detected

No output from drm though with the modules loaded:

# lsmod
Module                  Size  Used by
omapdrm                69632  0
drm_kms_helper        163840  1 omapdrm
cfbfillrect            16384  1 drm_kms_helper
syscopyarea            16384  1 drm_kms_helper
cfbimgblt              16384  1 drm_kms_helper
sysfillrect            16384  1 drm_kms_helper
sysimgblt              16384  1 drm_kms_helper
fb_sys_fops            16384  1 drm_kms_helper
cfbcopyarea            16384  1 drm_kms_helper
drm                   364544  2 omapdrm,drm_kms_helper
panel_sony_acx565akm    16384  0
omapdss               192512  1
omapdss_base           24576  3 panel_sony_acx565akm,omapdrm,omapdss
tsc2005                16384  0
tsc200x_core           16384  1 tsc2005
twl4030_keypad         16384  0
matrix_keymap          16384  1 twl4030_keypad
rtc_twl                16384  1
twl4030_wdt            16384  0

Am I missing some module now?

> I tried x15 on next. I see
> 
> BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
> 
> and
> 
> WARNING: possible circular locking dependency detected
> 
> But I don't think those affect DSS.
> 
> I see cma allocs failing for many drivers:
> 
> cma: cma_alloc: alloc failed, req-size: 1 pages, ret: -16
> 
> Which obviously breaks dss...

Yeah things seem quite broken in next again :( That cma_alloc issue is
caused by commit c11a39772b51 ("mm: drop migrate type checks from
has_unmovable_pages") and has a fix being discussed at:

https://patchwork.kernel.org/patch/10016595/

But this n900 issue seems to be something different.

Regards,

Tony