Support for LCD in LK bootloader on Snapdragon410 with Linux kernel 4.4

Products Support DragonBoard410c
#1

Hi,

With reference to the post LINUX : MIPI DSI panel support, I have interfaced display with Snapdragon 410 in Linux.
Now I want to add the support for LCD in LK bootloader. I have enabled the splash screen and the panel in the LK. The LCD appears at the LK stage but after few seconds only the screen goes off and kernel crash appears with the following error:
pclk0_clk_src: rcg didn’t update its configuration.
[ 5.719975] ------------[ cut here ]------------
[ 5.720013] WARNING: at /home/einfochips/Qualcomm/Linux_410_16.06/Linaro_16.06/drivers/clk/qcom/clk-rcg2.c:109
[ 5.720063] Modules linked in:
[ 5.720073]
[ 5.720164] CPU: 1 PID: 29 Comm: kworker/u8:1 Not tainted 4.4.9-linaro-lt-qcom #22
[ 5.720191] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
[ 5.720511] Workqueue: deferwq deferred_probe_work_func
[ 5.720527] task: ffffffc0365b8c00 ti: ffffffc0365c4000 task.ti: ffffffc0365c4000
[ 5.720716] PC is at update_config+0xa8/0xb4
[ 5.720740] LR is at update_config+0xa8/0xb4

byte0_clk_src: rcg didn’t update its configuration.
[ 5.726207] ------------[ cut here ]------------

Can anyone please guide me in this to understand the flow of driver in drm and rectify the error?

Regards,
Divya

#2

Please can you share the whole backtrace.

5 seconds into the boot is probably when the kernel is turning off unused clocks (i.e. if you have enabled clocks on the bootloader to display the image then the kernel may try to shut them down if no built in driver has activated them).

#3

This issue has been resolved. DSI panel is appearing in both LK stage and after the Linux kernel boots up.

But now, what happens is : when we do hard reboot, in LK stage the backlight is ON but no image is displayed.
whereas when we do Soft reboot (from command line) image is displayed in the LK.

The following is the boot sequence which is same in both the cases:

++++++++++++++++func:target_display_init, line:546
,[70] ++++++++++++++++func:gcdb_display_init, line:376
[70] ++++++++++++++++++ hw_id:24, line:486, func:oem_panel_select, panel_name:ssd2080m_720p_video
[80] OEM panel override:ssd2080m_720p_video
[80] +++++++++++line:439 func:init_panel_data
[90] +++++++++++++++++func: init_platform_data line:291
[90] ++++++++++++++++++++++func:dsi_panel_initline:56
[100] ++++++++++++++++++++func:msm_display_init, line:241
[110] +++++++++++++++++++++func:msm_display_init, LINE:279
[110] +++++++++++++++++++++func:msm_fb_alloc, LINE:42
[120] +++++++++++++++++++++func:msm_display_init, LINE:284
[120] +++++++++++++++++++++func:fbcon_setup, LINE:178
[130] +++++++++++++++++++++func:display_image_on_screen, LINE:224
[130] +++++++++++++++++++++func:fbcon_clear, LINE:124
[140] +++++++++++++++++++++func:fetch_image_from_partition, LINE:2778
[140] +++++++++++++++++++++func:splash_screen_mmc, LINE:2727
[150] +++++++++++++++++++++func:splash_screen_mmc, LINE:2734
[150] ERROR: splash Partition invalid
[160] +++++++++++++++++++++func:fbcon_putImage, LINE:255
[170] +++++++++++++++++++++func:fbcon_flush, LINE:94
[170] Config MIPI_VIDEO_PANEL.
[270] ++++++++++++++++++++func:mdss_dsi_panel_initialize, line:513
[340] ++++++++++++++++++++func:msm_display_on, line:148
[340] Turn on MIPI_VIDEO_PANEL.
[340] ++++++++++++++++++++func:mdss_dsi_post_on, line:818
[360] Video lane tested successfully

If anyone can please help me in this.

Regards,
Divya