On 10/08/17 13:15, Vladimir Murzin wrote:
> On 26/07/17 11:27, Russell King - ARM Linux wrote:
>> I suspect the above failure is down to either (a) not having enough
>> memory available to allocate a 1920x1080 frame buffer, or (b) not
>> (yet) being able to program the hdlcd pixel clock for this platform,
>> which is currently hard-coded in DT at 23.75MHz.
>
> Given it is NOMMU it is likely (a). Usually, tweaking FORCE_MAX_ZONEORDER
> helped me in such cases.
Ok, with CONFIG_FORCE_MAX_ZONEORDER=12 I see
[ 5.242423] [drm] found ARM HDLCD version r0p0
[ 5.493835] tda998x 2-0070: found TDA19988
[ 5.527771] hdlcd 40205000.hdlcd: bound 2-0070 (ops 0x1470f8)
[ 5.535819] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 5.543478] [drm] No driver support for vblank timestamp query.
[ 7.443189] hdlcd 40205000.hdlcd: fb0: frame buffer device
[ 7.501975] [drm] Initialized hdlcd 1.0.0 20151021 for 40205000.hdlcd on minor 0
when display is connected.
To make fb-test [1] happy I had to apply following diff:
diff --git a/drivers/gpu/drm/arm/Kconfig b/drivers/gpu/drm/arm/Kconfig
index 9a18e1b..d4cb1b1 100644
--- a/drivers/gpu/drm/arm/Kconfig
+++ b/drivers/gpu/drm/arm/Kconfig
@@ -10,6 +10,7 @@ config DRM_HDLCD
select DRM_ARM
select DRM_KMS_HELPER
select DRM_KMS_CMA_HELPER
+ select FB_PROVIDE_GET_FB_UNMAPPED_AREA if !MMU
help
Choose this option if you have an ARM High Definition Colour LCD
controller.
(The only user of FB_PROVIDE_GET_FB_UNMAPPED_AREA is NOMMU only drivers/gpu/drm/stm/)
However, I do not see anything on the screen. I'm probably missing something
obvious, so if you have an idea, please let me know and I can test the patch.
[1] https://github.com/prpplague/fb-test-app.git
Thanks
Vladimir
>
> Cheers
> Vladimir
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
