drm/bridge: Synopsys DW-HDMI bridge driver for the Ingenic JZ4780 (was Re: Specialising the Synopsys DW-HDMI bridge driver for the Ingenic JZ4780)
Paul Boddie
paul at boddie.org.uk
Thu May 14 22:04:51 UTC 2020
Hello,
Following up on my last message...
> On Wednesday 13. May 2020 09.37.49 Neil Armstrong wrote:
> >
> > Can you run the kernel with drm debug enabled ? drm.debug=0x3f for example
> > you'll have all the modes checks & so on
>
> I'll try and do this.
Well, I've done this but I probably need to know what to look for. One thing
that appears regardless of this debugging output being enabled is a problem
with the vertical blanking functionality:
WARNING: CPU: 1 PID: 396 at drivers/gpu/drm/drm_atomic_helper.c:1457
drm_atomic_helper_wait_for_vblanks+0x1ec/0x25c
[CRTC:32:crtc-0] vblank wait timed out
This is preceded by the following:
[drm:drm_atomic_commit] committing 1d53fa19
[drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CRTC:32:crtc-0]
flip_done timed out
[drm:drm_atomic_helper_wait_for_dependencies] *ERROR* [CONNECTOR:34:HDMI-A-1]
flip_done timed out
[drm:drm_calc_timestamping_constants] crtc 32: hwmode: htotal 1688, vtotal
1066, vdisplay 1024
[drm:drm_calc_timestamping_constants] crtc 32: clock 108000 kHz framedur
16661185 linedur 15629
[drm:drm_update_vblank_count] updating vblank count on crtc 0: current=1,
diff=0, hw=0 hw_last=0
Although the interrupt initialisation should be straightforward, maybe
something isn't getting done.
[...]
> > Please use the "modetest" utility from the libdrm source package, it will
> > list all the available mode and permit testing other modes.
>
> I'll give this a try. The modetest program was suggested by someone else as
> well, so it seems to be the way to go.
Well, I obtained libdrm and built it (after getting a much later version of
meson than my distribution provides), and running modetest with the options
indicated to me by another correspondent...
modetest -D /dev/dri/card0 -M ingenic-drm
...I get the following report:
-----------------------------------------------------------
Encoders:
id crtc type possible crtcs possible clones
33 32 DPI 0x00000001 0x00000000
Connectors:
id encoder status name size (mm) modes
encoders
34 33 connected HDMI-A-1 340x270 17 33
modes:
index name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot)
#0 1280x1024 60.02 1280 1328 1440 1688 1024 1025 1028 1066 108000 flags:
phsync, pvsync; type: preferred, driver
#1 1280x1024 75.02 1280 1296 1440 1688 1024 1025 1028 1066 135000 flags:
phsync, pvsync; type: driver
#2 1280x960 60.00 1280 1376 1488 1800 960 961 964 1000 108000 flags: phsync,
pvsync; type: driver
#3 1152x864 75.00 1152 1216 1344 1600 864 865 868 900 108000 flags: phsync,
pvsync; type: driver
#4 1024x768 75.03 1024 1040 1136 1312 768 769 772 800 78750 flags: phsync,
pvsync; type: driver
#5 1024x768 70.07 1024 1048 1184 1328 768 771 777 806 75000 flags: nhsync,
nvsync; type: driver
#6 1024x768 60.00 1024 1048 1184 1344 768 771 777 806 65000 flags: nhsync,
nvsync; type: driver
#7 832x624 74.55 832 864 928 1152 624 625 628 667 57284 flags: nhsync,
nvsync; type: driver
#8 800x600 75.00 800 816 896 1056 600 601 604 625 49500 flags: phsync,
pvsync; type: driver
#9 800x600 72.19 800 856 976 1040 600 637 643 666 50000 flags: phsync,
pvsync; type: driver
#10 800x600 60.32 800 840 968 1056 600 601 605 628 40000 flags: phsync,
pvsync; type: driver
#11 800x600 56.25 800 824 896 1024 600 601 603 625 36000 flags: phsync,
pvsync; type: driver
#12 640x480 75.00 640 656 720 840 480 481 484 500 31500 flags: nhsync,
nvsync; type: driver
#13 640x480 72.81 640 664 704 832 480 489 492 520 31500 flags: nhsync,
nvsync; type: driver
#14 640x480 66.67 640 704 768 864 480 483 486 525 30240 flags: nhsync,
nvsync; type: driver
#15 640x480 59.94 640 656 752 800 480 490 492 525 25175 flags: nhsync,
nvsync; type: driver
#16 720x400 70.08 720 738 846 900 400 412 414 449 28320 flags: nhsync,
pvsync; type: driver
props:
1 EDID:
flags: immutable blob
blobs:
value:
00ffffffffffff00047232ad01010101
2d0e010380221b782aaea5a6544c9926
145054bfef0081808140714f01010101
010101010101302a009851002a403070
1300520e1100001e000000ff00343435
3030353444454330300a000000fc0041
4c313731350a202020202020000000fd
00384c1e520e000a2020202020200051
2 DPMS:
flags: enum
enums: On=0 Standby=1 Suspend=2 Off=3
value: 3
5 link-status:
flags: enum
enums: Good=0 Bad=1
value: 0
6 non-desktop:
flags: immutable range
values: 0 1
value: 0
4 TILE:
flags: immutable blob
blobs:
value:
20 CRTC_ID:
flags: object
value: 32
CRTCs:
id fb pos size
32 38 (0,0) (1280x1024)
#0 60.02 1280 1328 1440 1688 1024 1025 1028 1066 108000 flags: phsync,
pvsync; type:
props:
22 ACTIVE:
flags: range
values: 0 1
value: 0
23 MODE_ID:
flags: blob
blobs:
value:
e0a5010000053005a005980600000004
010404042a0400000000000005000000
00000000000000000000000000000000
00000000000000000000000000000000
00000000
19 OUT_FENCE_PTR:
flags: range
values: 0 18446744073709551615
value: 0
24 VRR_ENABLED:
flags: range
values: 0 1
value: 0
Planes:
id crtc fb CRTC x,y x,y gamma size possible crtcs
31 32 38 0,0 0,0 0 0x00000001
formats: XR15 RG16 XR24
props:
8 type:
flags: immutable enum
enums: Overlay=0 Primary=1 Cursor=2
value: 1
17 FB_ID:
flags: object
value: 38
18 IN_FENCE_FD:
flags: signed range
values: -1 2147483647
value: -1
20 CRTC_ID:
flags: object
value: 32
13 CRTC_X:
flags: signed range
values: -2147483648 2147483647
value: 0
14 CRTC_Y:
flags: signed range
values: -2147483648 2147483647
value: 0
15 CRTC_W:
flags: range
values: 0 2147483647
value: 1280
16 CRTC_H:
flags: range
values: 0 2147483647
value: 1024
9 SRC_X:
flags: range
values: 0 4294967295
value: 0
10 SRC_Y:
flags: range
values: 0 4294967295
value: 0
11 SRC_W:
flags: range
values: 0 4294967295
value: 83886080
12 SRC_H:
flags: range
values: 0 4294967295
value: 67108864
Frame buffers:
id size pitch
-----------------------------------------------------------
For completeness, this is what /sys/kernel/debug/dri/0/state shows:
-----------------------------------------------------------
plane[31]: plane-0
crtc=crtc-0
fb=38
allocated by = Xorg
refcount=2
format=XR24 little-endian (0x34325258)
modifier=0x0
size=1280x1024
layers:
size[0]=1280x1024
pitch[0]=5120
offset[0]=0
obj[0]:
name=0
refcount=3
start=00010500
size=5242880
imported=no
crtc-pos=1280x1024+0+0
src-pos=1280.000000x1024.000000+0.000000+0.000000
rotation=1
normalized-zpos=0
color-encoding=ITU-R BT.601 YCbCr
color-range=YCbCr limited range
crtc[32]: crtc-0
enable=1
active=0
self_refresh_active=0
planes_changed=0
mode_changed=0
active_changed=0
connectors_changed=0
color_mgmt_changed=0
plane_mask=1
connector_mask=1
encoder_mask=1
mode: "": 0 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x0 0x5
connector[34]: HDMI-A-1
crtc=crtc-0
self_refresh_aware=0
-----------------------------------------------------------
Some other output:
-----------------------------------------------------------
# cat /sys/devices/platform/13050000.lcd/graphics/fb0/mode
# cat /sys/devices/platform/13050000.lcd/graphics/fb0/modes
U:1280x1024p-0
# cat /sys/devices/platform/13050000.lcd/graphics/fb0/state
0
# cat /sys/devices/platform/13050000.lcd/drm/card0/card0-HDMI-A-1/enabled
enabled
# cat /sys/devices/platform/13050000.lcd/drm/card0/card0-HDMI-A-1/modes
1280x1024
1280x1024
1280x960
1152x864
1024x768
1024x768
1024x768
832x624
800x600
800x600
800x600
800x600
640x480
640x480
640x480
640x480
720x400
# cat /sys/devices/platform/13050000.lcd/drm/card0/card0-HDMI-A-1/status
connected
-----------------------------------------------------------
Attempting to set a mode using...
modetest -D /dev/dri/card0 -M ingenic-drm -s 34 at 32:1280x1024-60.02
...yields the following:
failed to set mode: Permission denied
setting mode 1280x1024-60.02Hz at XR24 on connectors 34, crtc 32
[...]
> > But if you have "Input not supported" on your monitor, this means you have
> > TMDS going out on your hardware, which is good, this means all the
> > power/reset/system clocks are ok.
> > This could mean you have a timing/clock issue, please check if something
> > is not done on the pixel clock before going to the dw-hdmi block.
>
> I think I may have overlooked timing details, so this will also be a focus
> of mine as I review what I have done so far.
What I did look at today was the Ingenic DRM driver initialisation. There are
certain things that are not done in this driver that the vendor driver does
do.
For example, there is some kind of priority level register (PCFG) that is set
up with a "magic value" that can be largely explained by the programming
manual. Also, there is a RGB control register that older Ingenic SoCs do not
provide, and this is set up by the vendor driver. I have no idea whether they
play any role in this, but I introduced their initialisation anyway.
There was also a configuration register field related to the bus signalling
(JZ_LCD_CFG_PCLK_FALLING_EDGE) not being set because it is dependent on the
appropriate bus flag being set (DRM_BUS_FLAG_PIXDATA_NEGEDGE), which may not
have been occurring. Unfortunately, setting the bus flag in the bridge driver
didn't yield any progress.
So that is what I have discovered today.
Thanks once again for the advice!
Paul
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