Re: [Letux-kernel] [PATCH 8/8] drm/ingenic: Attach bridge chain to encoders

From: Paul Boddie
Date: Tue Aug 10 2021 - 17:15:30 EST

On Tuesday, 10 August 2021 09:52:36 CEST Paul Cercueil wrote:
>
> Le mar., août 10 2021 at 01:17:20 +0200, Paul Boddie <paul@xxxxxxxxxxxxx> a
écrit :
> >
> > But then the reported error occurs in the DRM driver:
> >
> > ingenic-drm 13050000.lcdc0: Unable to init connector
> > ingenic-drm: probe of 13050000.lcdc0 failed with error -22
> >
> > This originates in a call to drm_bridge_connector_init from
> > ingenic_drm_bind:
> >
> > connector = drm_bridge_connector_init(drm, encoder);
> >
> > The invoked function iterates over the registered bridges, one of
> > which seems to be the HDMI peripheral (it has bridge operations defined
> > identically to those specified in the Synopsys driver), but the type
> > member of the drm_bridge structure is set to 0
> > (DRM_MODE_CONNECTOR_Unknown).

Although I had fancy ideas about finding the connector node in the device tree
and populating the necessary type details on the bridge, I decided to just add
the following to the Synopsys driver's dw_hdmi_probe function:

hdmi->bridge.type = DRM_MODE_CONNECTOR_HDMIA;

This then lets the above invocation succeed and the Ingenic DRM driver
initialises. However, I get "Input Not Supported" on my display.

Conveniently, when indicating the necessary boot arguments...

env set bootargs ... drm.debug=0x3f

...as suggested to me on a previous occasion, the /sys/kernel/debug/dri/0/
state file indicates the following:

plane[31]: plane-0
crtc=crtc-0
fb=36
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=00010000
size=5242880
imported=no
paddr=0x00c00000
vaddr=3eb0c080
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
plane[33]: plane-1
crtc=(null)
fb=0
crtc-pos=0x0+0+0
src-pos=0.000000x0.000000+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=1
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: "": 60 108000 1280 1328 1440 1688 1024 1025 1028 1066 0x0 0x5
connector[35]: HDMI-A-1
crtc=crtc-0
self_refresh_aware=0

I suspect that we may be dealing with an incompatible bus format again, but I
may be quite wrong about that, too.

Here is the result of running modetest using...

sudo ./modetest -D /dev/dri/card0 -M ingenic-drm

Encoders:
id crtc type possible crtcs possible clones
34 32 DPI 0x00000001 0x00000001

Connectors:
id encoder status name size (mm) modes
encoders
35 34 connected HDMI-A-1 340x270 17 34
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 36 (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
010404042a0400003c00000005000000
00000000000000000000000000000000
00000000000000000000000000000000
00000000
19 OUT_FENCE_PTR:
flags: range
values: 0 18446744073709551615
value: 0
24 VRR_ENABLED:
flags: range
values: 0 1
value: 0
28 GAMMA_LUT:
flags: blob
blobs:

value:
29 GAMMA_LUT_SIZE:
flags: immutable range
values: 0 4294967295
value: 256

Planes:
id crtc fb CRTC x,y x,y gamma size possible crtcs
31 32 36 0,0 0,0 0 0x00000001
formats: XR15 RG16 RG24 XR24 XR30
props:
8 type:
flags: immutable enum
enums: Overlay=0 Primary=1 Cursor=2
value: 1
17 FB_ID:
flags: object
value: 36
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
33 0 0 0,0 0,0 0 0x00000001
formats: C8 XR15 RG16 RG24 XR24 XR30
props:
8 type:
flags: immutable enum
enums: Overlay=0 Primary=1 Cursor=2
value: 0
17 FB_ID:
flags: object
value: 0
18 IN_FENCE_FD:
flags: signed range
values: -1 2147483647
value: -1
20 CRTC_ID:
flags: object
value: 0
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: 0
16 CRTC_H:
flags: range
values: 0 2147483647
value: 0
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: 0
12 SRC_H:
flags: range
values: 0 4294967295
value: 0

Frame buffers:
id size pitch

Just in case that means anything to anyone.

Paul