Hi Saravana,
I am investigating a hang during resume from s2idle on the Gray
Hawk Single development board[1]. It was reported first in [2].
The issue was detected when support for DisplayPort was added, due to
DTS and driver updates following different paths to upstream.
When using a DTS with DisplayPort support, but booting a kernel that
lacks support for the DSI block, the display and DSI-DP bridge drivers
fail to probe, as expected:
# cat /sys/kernel/debug/devices_deferred
feb00000.display rcar-du: failed to initialize encoders
ti_sn65dsi86.bridge.0 ti_sn65dsi86.bridge: failed to attach dsi host
However, when using s2idle, the system fails to wake-up, which is
not expected.
The issue can be reproduced by reverting commit c303814c38cde135
("drm/rcar-du: dsi: Add r8a779h0 support") on top of v6.14-rc1.
Instrumenting all dev->power.completion accesses in
drivers/base/power/main.c reveals that resume is blocked in dpm_wait()
in the call to wait_for_completion() for regulator-1p2v, which is
indeed a dependency for the SN65DSI86 DSI-DP bridge. Comparing
this to plain v6.14-rc1 (where resume works fine) shows that the regulator
is woken by complete_all() there. As the logs are rather large,
I made them available at [3] and [4] (I added "----" sync markers for
"diff -y"). The important difference bad vs. good is:
-ti_sn65dsi86 1-002c: PM: dpm_wait:241: wait_for_completion
-i2c i2c-0: PM: device_resume_noirq:700: complete_all
-i2c i2c-1: PM: device_resume_noirq:700: complete_all
-i2c i2c-1: PM: dpm_wait:241: completed
-i2c i2c-0: PM: dpm_wait:241: completed
+rcar-mipi-dsi fed80000.dsi-encoder: PM: device_resume_noirq:700:
complete_all
+platform fff00044.chipid: PM: device_resume_noirq:700: complete_all
+platform timer: PM: device_resume_noirq:700: complete_all
+gpio-keys keys: PM: device_resume_noirq:700: complete_all
+leds-gpio leds: PM: device_resume_noirq:700: complete_all
+display-connector mini-dp-con: PM: device_resume_noirq:700: complete_all
+reg-fixed-voltage regulator-1p2v: PM: device_resume_noirq:700: complete_all
+reg-fixed-voltage regulator-1p8v: PM: device_resume_noirq:700: complete_all
+reg-fixed-voltage regulator-3p3v: PM: device_resume_noirq:700: complete_all
+simple-mux sound-mux: PM: device_resume_noirq:700: complete_all
+workqueue writeback: PM: device_resume_noirq:700: complete_all
+graphics fbcon: PM: device_resume_noirq:700: complete_all
+regulator regulator.1: PM: device_resume_noirq:700: complete_all
+regulator regulator.2: PM: device_resume_noirq:700: complete_all
+regulator regulator.3: PM: device_resume_noirq:700: complete_all
+net lo: PM: device_resume_noirq:700: complete_all
+misc vga_arbiter: PM: device_resume_noirq:700: complete_all
+mem mem: PM: device_resume_noirq:700: complete_all
+mem null: PM: device_resume_noirq:700: complete_all
+mem port: PM: device_resume_noirq:700: complete_all
+mem zero: PM: device_resume_noirq:700: complete_all
+mem full: PM: device_resume_noirq:700: complete_all
+mem random: PM: device_resume_noirq:700: complete_all
+mem urandom: PM: device_resume_noirq:700: complete_all
+mem kmsg: PM: device_resume_noirq:700: complete_all
+tty tty: PM: device_resume_noirq:700: complete_all
+tty console: PM: device_resume_noirq:700: complete_all
+tty tty0: PM: device_resume_noirq:700: complete_all
+vc vcs: PM: device_resume_noirq:700: complete_all
+vc vcsu: PM: device_resume_noirq:700: complete_all
+vc vcsa: PM: device_resume_noirq:700: complete_all
+vc vcs1: PM: device_resume_noirq:700: complete_all
+vc vcsu1: PM: device_resume_noirq:700: complete_all
+vc vcsa1: PM: device_resume_noirq:700: complete_all
+tty tty1: PM: device_resume_noirq:700: complete_all
+tty tty2: PM: device_resume_noirq:700: complete_all
+tty tty3: PM: device_resume_noirq:700: complete_all
+tty tty4: PM: device_resume_noirq:700: complete_all
+tty tty5: PM: device_resume_noirq:700: complete_all
+tty tty6: PM: device_resume_noirq:700: complete_all
+tty tty7: PM: device_resume_noirq:700: complete_all
+tty tty8: PM: device_resume_noirq:700: complete_all
+tty tty9: PM: device_resume_noirq:700: complete_all
+tty tty10: PM: device_resume_noirq:700: complete_all
+tty tty11: PM: device_resume_noirq:700: complete_all
+tty tty12: PM: device_resume_noirq:700: complete_all
+tty tty13: PM: device_resume_noirq:700: complete_all
+tty tty14: PM: device_resume_noirq:700: complete_all
+tty tty15: PM: device_resume_noirq:700: complete_all
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
i2c i2c-0: PM: dpm_wait:241: completed
regulator regulator.0: PM: dpm_wait:241: wait_for_completion
regulator regulator.0: PM: dpm_wait:241: completed
-at24 0-0051: PM: device_resume_noirq:700: complete_all
+pca953x 0-0021: PM: device_resume_noirq:700: complete_all
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
i2c i2c-0: PM: dpm_wait:241: completed
regulator regulator.0: PM: dpm_wait:241: wait_for_completion
regulator regulator.0: PM: dpm_wait:241: completed
-at24 0-0050: PM: device_resume_noirq:700: complete_all
+pca953x 0-0022: PM: device_resume_noirq:700: complete_all
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
i2c i2c-0: PM: dpm_wait:241: completed
regulator regulator.0: PM: dpm_wait:241: wait_for_completion
regulator regulator.0: PM: dpm_wait:241: completed
-at24 0-0052: PM: device_resume_noirq:700: complete_all
-i2c i2c-0: PM: dpm_wait:241: completed
+at24 0-0051: PM: device_resume_noirq:700: complete_all
+tty tty16: PM: device_resume_noirq:700: complete_all
i2c i2c-0: PM: dpm_wait:241: completed
-regulator regulator.0: PM: dpm_wait:241: wait_for_completion
-regulator regulator.0: PM: dpm_wait:241: completed
+tty tty17: PM: device_resume_noirq:700: complete_all
gpio_rcar e6050180.gpio: PM: dpm_wait:241: wait_for_completion
-at24 0-0053: PM: device_resume_noirq:700: complete_all
+tty tty18: PM: device_resume_noirq:700: complete_all
gpio_rcar e6050180.gpio: PM: dpm_wait:241: completed
+tty tty19: PM: device_resume_noirq:700: complete_all
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
+i2c-rcar e6508000.i2c: PM: dpm_wait:241: wait_for_completion
i2c i2c-0: PM: dpm_wait:241: completed
+i2c-rcar e6508000.i2c: PM: dpm_wait:241: completed
+i2c i2c-1: PM: device_resume_noirq:700: complete_all
regulator regulator.0: PM: dpm_wait:241: wait_for_completion
-regulator regulator.0: PM: dpm_wait:241: wait_for_completion
+i2c i2c-0: PM: dpm_wait:241: wait_for_completion
regulator regulator.0: PM: dpm_wait:241: completed
+i2c i2c-0: PM: dpm_wait:241: completed
+regulator regulator.0: PM: dpm_wait:241: wait_for_completion
regulator regulator.0: PM: dpm_wait:241: completed
-pca953x 0-0020: PM: device_resume_noirq:700: complete_all
-pca953x 0-0021: PM: device_resume_noirq:700: complete_all
+at24 0-0052: PM: device_resume_noirq:700: complete_all
+at24 0-0053: PM: device_resume_noirq:700: complete_all
+mmc_host mmc0: PM: dpm_wait:241: wait_for_completion
+tty tty20: PM: device_resume_noirq:700: complete_all
+i2c i2c-0: PM: dpm_wait:241: completed
+tty tty21: PM: device_resume_noirq:700: complete_all
+regulator regulator.0: PM: dpm_wait:241: wait_for_completion
+tty tty22: PM: device_resume_noirq:700: complete_all
+i2c i2c-1: PM: dpm_wait:241: completed
+tty tty23: PM: device_resume_noirq:700: complete_all
sh-pfc e6050000.pinctrl: PM: dpm_wait:241: wait_for_completion
+tty tty24: PM: device_resume_noirq:700: complete_all
+regulator regulator.0: PM: dpm_wait:241: completed
+tty tty25: PM: device_resume_noirq:700: complete_all
+at24 0-0050: PM: device_resume_noirq:700: complete_all
+tty tty26: PM: device_resume_noirq:700: complete_all
regulator regulator.0: PM: dpm_wait:241: wait_for_completion
-sh-pfc e6050000.pinctrl: PM: dpm_wait:241: completed
+tty tty27: PM: device_resume_noirq:700: complete_all
regulator regulator.0: PM: dpm_wait:241: completed
+tty tty28: PM: device_resume_noirq:700: complete_all
+sh-pfc e6050000.pinctrl: PM: dpm_wait:241: completed
+tty tty29: PM: device_resume_noirq:700: complete_all
reg-fixed-voltage regulator-1p2v: PM: dpm_wait:241: wait_for_completion
-pca953x 0-0022: PM: device_resume_noirq:700: complete_all
+tty tty30: PM: device_resume_noirq:700: complete_all
+pca953x 0-0020: PM: device_resume_noirq:700: complete_all
Looking at /sys/devices/virtual/devlink, the non-working case has the
following extra entries:
/sys/devices/virtual/devlink/i2c:1-002c--platform:fed80000.dsi-encoder:
-r--r--r-- 1 root root 4096 Feb 7 HH:MM auto_remove_on
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM consumer ->
../../../platform/soc/fed80000.dsi-encoder
-r--r--r-- 1 root root 4096 Feb 7 HH:MM runtime_pm
-r--r--r-- 1 root root 4096 Feb 7 HH:MM status
lrwxrwxrwx 1 root root 0 Dec 1 HH:MM subsystem ->
../../../../class/devlink
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM supplier ->
../../../platform/soc/e6508000.i2c/i2c-1/1-002c
-r--r--r-- 1 root root 4096 Feb 7 HH:MM sync_state_only
-rw-r--r-- 1 root root 4096 Dec 1 HH:MM uevent
/sys/devices/virtual/devlink/platform:feb00000.display--platform:fed80000.dsi-encoder:
-r--r--r-- 1 root root 4096 Feb 7 HH:MM auto_remove_on
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM consumer ->
../../../platform/soc/fed80000.dsi-encoder
-r--r--r-- 1 root root 4096 Feb 7 HH:MM runtime_pm
-r--r--r-- 1 root root 4096 Feb 7 HH:MM status
lrwxrwxrwx 1 root root 0 Dec 1 HH:MM subsystem ->
../../../../class/devlink
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM supplier ->
../../../platform/soc/feb00000.display
-r--r--r-- 1 root root 4096 Feb 7 HH:MM sync_state_only
-rw-r--r-- 1 root root 4096 Dec 1 HH:MM uevent
/sys/devices/virtual/devlink/platform:fed80000.dsi-encoder--platform:feb00000.display:
-r--r--r-- 1 root root 4096 Feb 7 HH:MM auto_remove_on
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM consumer ->
../../../platform/soc/feb00000.display
-r--r--r-- 1 root root 4096 Feb 7 HH:MM runtime_pm
-r--r--r-- 1 root root 4096 Feb 7 HH:MM status
lrwxrwxrwx 1 root root 0 Dec 1 HH:MM subsystem ->
../../../../class/devlink
lrwxrwxrwx 1 root root 0 Feb 7 HH:MM supplier ->
../../../platform/soc/fed80000.dsi-encoder
-r--r--r-- 1 root root 4096 Feb 7 HH:MM sync_state_only
-rw-r--r-- 1 root root 4096 Dec 1 HH:MM uevent
Do you have a clue, or suggestions for further investigation?
Thanks!
[1] arch/arm64/boot/dts/renesas/r8a779h0-gray-hawk-single.dts
[2] https://lore.kernel.org/CAMuHMdXkXx6+0nJn+uLCAWOXvEYWLJXzLu9J7ksinn_z3bEfHQ@xxxxxxxxxxxxxx
[3] https://drive.google.com/file/d/1yH_PjihKIauK44NZhVHtZeka6PaIPY78/view?usp=sharing
[4] https://drive.google.com/file/d/1zjGSQhEqsSLRw5cxP_xsBDcy3t3dkpcj/view?usp=sharing
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
