Wiadomość napisana przez Andy Yan [off-list ref] w dniu 12 mar 2025, o godz. 11:42:

From: Andy Yan <andy.yan@rock-chips.com>

The DW DP TX Controller is compliant with the DisplayPort Specification
Version 1.4 with the following features:

* DisplayPort 1.4a
* Main Link: 1/2/4 lanes
* Main Link Support 1.62Gbps, 2.7Gbps, 5.4Gbps and 8.1Gbps
* AUX channel 1Mbps
* Single Stream Transport(SST)
* Multistream Transport (MST)
* Type-C support (alternate mode)
* HDCP 2.2, HDCP 1.3
* Supports up to 8/10 bits per color component
* Supports RBG, YCbCr4:4:4, YCbCr4:2:2, YCbCr4:2:0
* Pixel clock up to 594MHz
* I2S, SPDIF audio interface

Add library with common helpers to make it can be shared with
other SoC.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>

---

Changes in v2:
- Fix compile error when build as module
- Add phy init
- Only use one dw_dp_link_train_set
- inline dw_dp_phy_update_vs_emph
- Use dp_sdp
- Check return value of drm_modeset_lock
- Merge code in atomic_pre_enable/mode_fixup to atomic_check
- Return NULL if can't find a supported output format
- Fix max_link_rate from plat_data

Andy,

Just small Q: do v2 needs something extra to get it working (particular kernel ver or extra dependency patches)?
I just replaced v1 to v2 and dp stopped to work for me.

e.g. on rock5a i’m getting:

root@myth-frontend-fafc53b591a6:~ # dmesg | grep drm
[    9.245284] panthor fb000000.gpu: [drm] clock rate = 198000000
[    9.249464] panthor fb000000.gpu: [drm] mali-g610 id 0xa867 major 0x0 minor 0x0 status 0x5
[    9.249472] panthor fb000000.gpu: [drm] Features: L2:0x7120306 Tiler:0x809 Mem:0x301 MMU:0x2830 AS:0xff
[    9.249474] panthor fb000000.gpu: [drm] shader_present=0x50005 l2_present=0x1 tiler_present=0x1
[    9.257979] panthor fb000000.gpu: [drm] Firmware protected mode entry not be supported, ignoring
[    9.258030] panthor fb000000.gpu: [drm] Firmware git sha: 814b47b551159067b67a37c4e9adda458ad9d852
[    9.258604] panthor fb000000.gpu: [drm] CSF FW using interface v1.1.0, Features 0x0 Instrumentation features 0x71
[    9.259671] [drm] Initialized panthor 1.3.0 for fb000000.gpu on minor 0
[    9.324353] rockchip-drm display-subsystem: bound fdd90000.vop (ops vop2_component_ops)
[    9.324617] rockchip-drm display-subsystem: bound fde50000.dp (ops dw_dp_rockchip_component_ops)
[    9.325202] rockchip-drm display-subsystem: bound fde80000.hdmi (ops dw_hdmi_qp_rockchip_ops)
[    9.325506] [drm] Initialized rockchip 1.0.0 for display-subsystem on minor 1
[    9.325531] rockchip-drm display-subsystem: [drm] Cannot find any crtc or sizes
[    9.325594] rockchip-drm display-subsystem: [drm] Cannot find any crtc or sizes  

dp status is "not connected"

replacing only this patch back to v1 brings dp back to work.