Hi MyungJoo,

Thank you for taking the patch set.
Please check my response bellow.

On 12/11/18 2:43 AM, MyungJoo Ham wrote:

quoted

Hi Lukasz,

On 2018년 12월 05일 20:05, Lukasz Luba wrote:

quoted

The patch prepares devfreq device for handling suspend/resume
functionality. The new fields will store needed information during this
process. Devfreq framework handles opp-suspend DT entry and there is no
need of modyfications in the drivers code. It uses atomic variables to
make sure no race condition affects the process.

Suggested-by: Tobias Jakobi <redacted>
Suggested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lukasz Luba <redacted>
---
  drivers/devfreq/devfreq.c | 47 +++++++++++++++++++++++++++++++++++++++++------
  include/linux/devfreq.h   |  7 +++++++
  2 files changed, 48 insertions(+), 6 deletions(-)

Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>

Looks goot do me as well.

Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>


Anyway, for the sake of curiosity...

Having suspend-frequency is usually required when
the frequency configuration is reset with suspend-resume
as older Exynos's CPU did (I don't know whether it still does).

You are right, some Exynos SoCs like 4412 needs the proper configuration.

Does GPU do this as well?
(memory-bus won't do this because they are kept turned on during suspend)

I haven't seen GPU failures.
The CPU resume process can fail when some buses ('leftbus' (data 
bus/peripheral bus), 'rightbus', 'memory-bus')
are not operating with needed frequency.

Here is the log showing CPU1,2,3 booting failure:
-------------------------------------------------------------------
root@target:~# echo mem > /sys/power/state
[   43.432066] PM: suspend entry (deep)
[   43.481742] PM: Syncing filesystems ... done.
[   43.553433] Freezing user space processes ... (elapsed 0.002 seconds) 
done.
[   43.556687] OOM killer disabled.
[   43.556694] Freezing remaining freezable tasks ... (elapsed 0.001 
seconds) done.
[   43.558305] printk: Suspending console(s) (use no_console_suspend to 
debug)

[   43.718007] dwc2 12480000.hsotg: suspending usb gadget g_ether
[   43.718229] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[   43.718260] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[   43.722021] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[   43.722038] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[   43.781714] wake enabled for irq 134
[   43.781822] CAM_ISP_CORE_1.2V: No configuration
[   43.781918] VMEM_VDDF_3.0V: No configuration
[   43.781952] VCC_SUB_2.0V: No configuration
[   43.781986] VCC_SUB_1.35V: No configuration
[   43.782018] VMEM_1.2V_AP: No configuration
[   43.787139] MOTOR_VCC_3.0V: No configuration
[   43.787176] LCD_VCC_3.3V: No configuration
[   43.787209] TSP_VDD_1.8V: No configuration
[   43.787242] TSP_AVDD_3.3V: No configuration
[   43.787273] VMEM_VDD_2.8V: No configuration
[   43.787305] VTF_2.8V: No configuration
[   43.787422] VDDQ_PRE_1.8V: No configuration
[   43.787456] VT_CAM_1.8V: No configuration
[   43.787488] CAM_ISP_SEN_IO_1.8V: No configuration
[   43.787521] CAM_SENSOR_CORE_1.2V: No configuration
[   43.789160] NFC_AVDD_1.8V: No configuration
[   43.792571] CAM_ISP_MIPI_1.2V: No configuration
[   43.794209] VCC_1.8V_IO: No configuration
[   43.794244] VCC_2.8V_AP: No configuration
[   43.794279] VCC_1.8V_AP: No configuration
[   43.794331] VALIVE_1.0V_AP: No configuration
[   43.805821] wake enabled for irq 138
[   43.806368] wake enabled for irq 160
[   43.806382] wake enabled for irq 161
[   43.824045] samsung-pinctrl 11000000.pinctrl: Setting external wakeup 
interrupt mask: 0xff77ff7d
[   43.841162] Disabling non-boot CPUs ...
[   43.863016] Enabling non-boot CPUs ...
[   43.864749] ------------[ cut here ]------------
[   43.864779] WARNING: CPU: 1 PID: 0 at 
./arch/arm/include/asm/proc-fns.h:124 secondary_start_kernel+0x20c/0x268
[   43.864788] Modules linked in:
[   43.864805] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 
4.20.0-rc2-next-20181114-00007-g5506a9cd6bd7 #1042
[   43.864813] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   43.864835] [<c011261c>] (unwind_backtrace) from [<c010e150>] 
(show_stack+0x10/0x14)
[   43.864852] [<c010e150>] (show_stack) from [<c0a4b0a0>] 
(dump_stack+0x98/0xc4)
[   43.864870] [<c0a4b0a0>] (dump_stack) from [<c01270a4>] 
(__warn+0x10c/0x124)
[   43.864884] [<c01270a4>] (__warn) from [<c01271d0>] 
(warn_slowpath_null+0x40/0x48)
[   43.864899] [<c01271d0>] (warn_slowpath_null) from [<c0110ee0>] 
(secondary_start_kernel+0x20c/0x268)
[   43.864913] [<c0110ee0>] (secondary_start_kernel) from [<401027ac>] 
(0x401027ac)
[   43.864923] irq event stamp: 982984
[   43.864942] hardirqs last  enabled at (982983): [<c0a6cc6c>] 
_raw_spin_unlock_irqrestore+0x6c/0x74
[   43.864954] hardirqs last disabled at (982984): [<c0110c68>] 
arch_cpu_idle_dead+0x18/0x84
[   43.864969] softirqs last  enabled at (982964): [<c012f0e0>] 
irq_enter+0x78/0x80
[   43.864980] softirqs last disabled at (982963): [<c012f0cc>] 
irq_enter+0x64/0x80
[   43.864989] ---[ end trace 6401b9331547e26f ]---
[   43.864996] ------------[ cut here ]------------
[   43.865009] WARNING: CPU: 1 PID: 0 at 
./arch/arm/include/asm/proc-fns.h:126 secondary_start_kernel+0x244/0x268
[   43.865016] Modules linked in:
[   43.865030] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G        W 
4.20.0-rc2-next-20181114-00007-g5506a9cd6bd7 #1042
[   43.865039] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[   43.865054] [<c011261c>] (unwind_backtrace) from [<c010e150>] 
(show_stack+0x10/0x14)
[   43.865068] [<c010e150>] (show_stack) from [<c0a4b0a0>] 
(dump_stack+0x98/0xc4)
[   43.865081] [<c0a4b0a0>] (dump_stack) from [<c01270a4>] 
(__warn+0x10c/0x124)
[   43.865095] [<c01270a4>] (__warn) from [<c01271d0>] 
(warn_slowpath_null+0x40/0x48)
[   43.865109] [<c01271d0>] (warn_slowpath_null) from [<c0110f18>] 
(secondary_start_kernel+0x244/0x268)
[   43.865122] [<c0110f18>] (secondary_start_kernel) from [<401027ac>] 
(0x401027ac)
[   43.865131] irq event stamp: 982984
[   43.865144] hardirqs last  enabled at (982983): [<c0a6cc6c>] 
_raw_spin_unlock_irqrestore+0x6c/0x74
[   43.865156] hardirqs last disabled at (982984): [<c0110c68>] 
arch_cpu_idle_dead+0x18/0x84
[   43.865168] softirqs last  enabled at (982964): [<c012f0e0>] 
irq_enter+0x78/0x80
[   43.865179] softirqs last disabled at (982963): [<c012f0cc>] 
irq_enter+0x64/0x80
[   43.865187] ---[ end trace 6401b9331547e270 ]---
[   44.856140] CPU1: failed to boot: -110
[   44.856956] Error taking CPU1 up: -110
[   45.856655] CPU2: failed to boot: -110
[   45.857770] Error taking CPU2 up: -110
[   46.856059] CPU3: failed to boot: -110
[   46.856721] Error taking CPU3 up: -110
-------------------------------------------------------------------

With the patch set, the CPUs are up and running.
-------------------------------------------------------------------
==========================================================
root@target:~# echo mem > /sys/power/state
[ 1135.879168] PM: suspend entry (deep)
[ 1135.906378] PM: Syncing filesystems ...
[ 1135.919299] mmc_host mmc2: Bus speed (slot 0) = 50000000Hz (slot req 
400000Hz, actual 396825HZ div = 63)
[ 1136.137522] mmc_host mmc2: Bus speed (slot 0) = 50000000Hz (slot req 
52000000Hz, actual 50000000HZ div = 0)
[ 1136.184722] done.
[ 1136.196373] Freezing user space processes ... (elapsed 0.001 seconds) 
done.
[ 1136.197689] OOM killer disabled.
[ 1136.197692] Freezing remaining freezable tasks ... (elapsed 0.001 
seconds) done.
[ 1136.198923] printk: Suspending console(s) (use no_console_suspend to 
debug)
[ 1136.364056] devfreq8, suspend_freq=200000000
[ 1136.364114] devfreq4, suspend_freq=200000000
[ 1136.364174] devfreq3, suspend_freq=200000000
[ 1136.364217] devfreq2, suspend_freq=400000000
[ 1136.364311] devfreq0, suspend_freq=400000000
[ 1136.425416] wake enabled for irq 134
[ 1136.425439] CAM_ISP_CORE_1.2V: No configuration
[ 1136.425457] VMEM_VDDF_3.0V: No configuration
[ 1136.425476] VCC_SUB_2.0V: No configuration
[ 1136.425493] VCC_SUB_1.35V: No configuration
[ 1136.425510] VMEM_1.2V_AP: No configuration
[ 1136.426939] MOTOR_VCC_3.0V: No configuration
[ 1136.426958] LCD_VCC_3.3V: No configuration
[ 1136.426976] TSP_VDD_1.8V: No configuration
[ 1136.426994] TSP_AVDD_3.3V: No configuration
[ 1136.427012] VMEM_VDD_2.8V: No configuration
[ 1136.427029] VTF_2.8V: No configuration
[ 1136.427047] VDDQ_PRE_1.8V: No configuration
[ 1136.427064] VT_CAM_1.8V: No configuration
[ 1136.427082] CAM_ISP_SEN_IO_1.8V: No configuration
[ 1136.427100] CAM_SENSOR_CORE_1.2V: No configuration
[ 1136.427605] NFC_AVDD_1.8V: No configuration
[ 1136.429020] CAM_ISP_MIPI_1.2V: No configuration
[ 1136.429859] VCC_1.8V_IO: No configuration
[ 1136.429879] VCC_2.8V_AP: No configuration
[ 1136.429898] VCC_1.8V_AP: No configuration
[ 1136.429926] VALIVE_1.0V_AP: No configuration
[ 1136.435110] wake enabled for irq 138
[ 1136.435381] wake enabled for irq 160
[ 1136.435391] wake enabled for irq 161
[ 1136.443372] samsung-pinctrl 11000000.pinctrl: Setting external wakeup 
interrupt mask: 0xff77ff7d
[ 1136.450942] Disabling non-boot CPUs ...
[ 1136.575256] Enabling non-boot CPUs ...
[ 1136.577278] CPU1 is up
[ 1136.579226] CPU2 is up
[ 1136.581283] CPU3 is up
[ 1136.581773] s3c-i2c 13860000.i2c: slave address 0x10
[ 1136.581788] s3c-i2c 13860000.i2c: bus frequency set to 390 KHz
[ 1136.581809] s3c-i2c 13890000.i2c: slave address 0x10
[ 1136.581821] s3c-i2c 13890000.i2c: bus frequency set to 390 KHz
[ 1136.581841] s3c-i2c 138a0000.i2c: slave address 0x10
[ 1136.581866] s3c-i2c 138a0000.i2c: bus frequency set to 97 KHz
[ 1136.581887] s3c-i2c 138b0000.i2c: slave address 0x00
[ 1136.581899] s3c-i2c 138b0000.i2c: bus frequency set to 97 KHz
[ 1136.581919] s3c-i2c 138d0000.i2c: slave address 0x10
[ 1136.581930] s3c-i2c 138d0000.i2c: bus frequency set to 97 KHz
[ 1136.581949] s3c-i2c 138e0000.i2c: slave address 0x00
[ 1136.581961] s3c-i2c 138e0000.i2c: bus frequency set to 97 KHz
[ 1136.590858] s3c-rtc 10070000.rtc: rtc disabled, re-enabling
[ 1136.592539] s3c2410-wdt 10060000.watchdog: watchdog disabled
[ 1136.592636] wake disabled for irq 160
[ 1136.592646] wake disabled for irq 161
[ 1136.592768] wake disabled for irq 138
[ 1136.596830] wake disabled for irq 134
[ 1136.648824] mmc1: queuing unknown CIS tuple 0x80 (7 bytes)
[ 1136.651430] mmc1: queuing unknown CIS tuple 0x80 (6 bytes)
[ 1136.721638] devfreq8 resume_freq=200000000
[ 1136.721664] devfreq4 resume_freq=200000000
[ 1136.721681] devfreq3 resume_freq=200000000
[ 1136.721704] devfreq2 resume_freq=267000000
[ 1136.721738] devfreq0 resume_freq=267000000
[ 1136.944032] panel-samsung-s6e8aa0 11c80000.dsi.0: ID: 0xa2, 0x20, 0x8c
[ 1137.754939] OOM killer enabled.
[ 1137.760515] Restarting tasks ... done.
root@target:~# [ 1137.768132] PM: suspend exit
-------------------------------------------------------------------

Regards,
Lukasz

Cheers,
MyungJoo

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