Re: [PATCH] ARM: dts: exynos: Add proper regulator states for suspend-to-mem for odroid-u3

From: Anand Moon
Date: Wed Dec 05 2018 - 11:11:35 EST


Hi Krzysztof,

Thanks for your review.
.
On Wed, 5 Dec 2018 at 19:36, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>
> On Tue, 4 Dec 2018 at 20:40, Anand Moon <linux.amoon@xxxxxxxxx> wrote:
> >
> > Add suspend-to-mem node to regulator core to be enabled or disabled
> > during system suspend and also support changing the regulator operating
> > mode during runtime and when the system enter sleep mode.
> >
> > Signed-off-by: Anand Moon <linux.amoon@xxxxxxxxx>
> > ---
> > Tested on Odroid U3+
> > ---
> > .../boot/dts/exynos4412-odroid-common.dtsi | 72 +++++++++++++++++++
> > 1 file changed, 72 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> > index 2caa3132f34e..837713a2ec3b 100644
> > --- a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> > +++ b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> > @@ -285,6 +285,9 @@
> > regulator-min-microvolt = <1800000>;
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
>
> Driver does not support suspend_enable so this will be noop. We could
> add this for DT-correctness (and full description of HW) but then I
> need explanation why this regulator has to stay on during suspend.
>

Well I tried to study the suspend/resume feature from
*arch/arm/boot/dts/exynos4412-midas.dtsi*
and them I tried to apply the same with this on Odroid-U3 boards and
test these changes.

> > };
> >
> > ldo3_reg: LDO3 {
> > @@ -292,6 +295,9 @@
> > regulator-min-microvolt = <1800000>;
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
>
> The same but with suspend_disable.
>
> I am not saying that these are wrong but I would be happy to see
> explanations why you chosen these particular properties.
>

Well I was not aware on the regulator-always-on cannot be set to off
in suspend mode.
Will drop this in the future patch where regulator-always-on; is set.

> > };
> >
> > ldo4_reg: LDO4 {
> > @@ -299,6 +305,9 @@
> > regulator-min-microvolt = <2800000>;
> > regulator-max-microvolt = <2800000>;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > ldo5_reg: LDO5 {
> > @@ -307,6 +316,9 @@
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > ldo6_reg: LDO6 {
> > @@ -314,6 +326,9 @@
> > regulator-min-microvolt = <1000000>;
> > regulator-max-microvolt = <1000000>;
> > regulator-always-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > ldo7_reg: LDO7 {
> > @@ -321,18 +336,27 @@
> > regulator-min-microvolt = <1000000>;
> > regulator-max-microvolt = <1000000>;
> > regulator-always-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > ldo8_reg: LDO8 {
> > regulator-name = "VDD10_HDMI_1.0V";
> > regulator-min-microvolt = <1000000>;
> > regulator-max-microvolt = <1000000>;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo10_reg: LDO10 {
> > regulator-name = "VDDQ_MIPIHSI_1.8V";
> > regulator-min-microvolt = <1800000>;
> > regulator-max-microvolt = <1800000>;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo11_reg: LDO11 {
> > @@ -340,6 +364,9 @@
> > regulator-min-microvolt = <1800000>;
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo12_reg: LDO12 {
> > @@ -348,6 +375,9 @@
> > regulator-max-microvolt = <3300000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo13_reg: LDO13 {
> > @@ -356,6 +386,9 @@
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo14_reg: LDO14 {
> > @@ -364,6 +397,9 @@
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo15_reg: LDO15 {
> > @@ -372,6 +408,9 @@
> > regulator-max-microvolt = <1000000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo16_reg: LDO16 {
> > @@ -380,6 +419,9 @@
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > ldo20_reg: LDO20 {
> > @@ -387,6 +429,9 @@
> > regulator-min-microvolt = <1800000>;
> > regulator-max-microvolt = <1800000>;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > ldo21_reg: LDO21 {
> > @@ -394,6 +439,9 @@
> > regulator-min-microvolt = <2800000>;
> > regulator-max-microvolt = <2800000>;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
>
> That's unusual setting... enabled in suspend but not necessarily
> during work (no always-on).
>

I kept the regulator required for emmc/sd card in
regulator-on-in-suspend in suspend mode.

> > + };
> > };
> >
> > ldo22_reg: LDO22 {
> > @@ -411,6 +459,9 @@
> > regulator-max-microvolt = <1800000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
> > };
> >
> > buck1_reg: BUCK1 {
> > @@ -419,6 +470,9 @@
> > regulator-max-microvolt = <1100000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
> > + };
>
> This is seriously wrong so I have doubts whether you tested the
> changes or you know what is happening with them. If you turn off
> memory bus regulator off, how the memory will work in
> Suspend-to-Memory mode?
>

Well I did not find any issue in my testing but I might be wrong.
Ok I will drop this changes in the next version of the patch where
regulator-always-on is set.

> > };
> >
> > buck2_reg: BUCK2 {
> > @@ -427,6 +481,9 @@
> > regulator-max-microvolt = <1350000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-on-in-suspend;
> > + };
> > };
> >
> > buck3_reg: BUCK3 {
> > @@ -435,6 +492,9 @@
> > regulator-max-microvolt = <1050000>;
> > regulator-always-on;
> > regulator-boot-on;
> > + regulator-state-mem {
> > + regulator-off-in-suspend;
>
> Looks suspicious as well.

Ok I will drop this changes in the next version of the patch where
regulator-always-on is set.

>
> Best regards,
> Krzysztof
>

Well I have tested this patch as following
with only one issue, before enable suspend number of On-line cpu is 4
after resume number of On-line cpu is 1.

# lscpu
Architecture: armv7l
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
Vendor ID: ARM
Model: 0
Model name: Cortex-A9
Stepping: r3p0
CPU max MHz: 1704.0000
CPU min MHz: 200.0000
BogoMIPS: 48.00
Flags: half thumb fastmult vfp edsp neon vfpv3 tls vfpd32
#
# echo 1 > /sys/power/pm_debug_messages
# echo +30 > /sys/class/rtc/rtc0/wakealarm
# echo -n mem > /sys/power/state
[ 86.584147] PM: suspend entry (deep)
[ 86.584684] PM: Syncing filesystems ... done.
[ 86.735819] Freezing user space processes ... (elapsed 0.003 seconds) done.
[ 86.742319] OOM killer disabled.
[ 86.744018] Freezing remaining freezable tasks ... (elapsed 0.002
seconds) done.
[ 86.751479] printk: Suspending console(s) (use no_console_suspend to debug)
[ 86.792770] smsc95xx 1-2:1.0 eth0: entering SUSPEND2 mode
[ 86.821751] dwc2 12480000.hsotg: suspending usb gadget g_ether
[ 86.822560] dwc2 12480000.hsotg: new device is full-speed
[ 86.822666] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[ 86.822682] dwc2 12480000.hsotg: dwc2_hsotg_ep_disable: called for ep0
[ 86.824507] wake enabled for irq 119
[ 86.824592] BUCK9: No configuration
[ 86.824672] BUCK8_P3V3: No configuration
[ 86.824706] BUCK7_2.0V: No configuration
[ 86.824738] BUCK6_1.35V: No configuration
[ 86.824770] VDDQ_CKEM1_2_1.2V: No configuration
[ 86.826766] LDO26: No configuration
[ 86.826802] VDDQ_LCD_1.8V: No configuration
[ 86.826834] LDO24: No configuration
[ 86.826866] LDO23: No configuration
[ 86.826898] LDO22_VDDQ_MMC4_2.8V: No configuration
[ 86.826930] TFLASH_2.8V: No configuration
[ 86.826962] LDO20_1.8V: No configuration
[ 86.826994] LDO19: No configuration
[ 86.827026] LDO18: No configuration
[ 86.827057] LDO17: No configuration
[ 86.827516] VDDQ_C2C_W_1.8V: No configuration
[ 86.828324] VDDQ_MIPIHSI_1.8V: No configuration
[ 86.828359] LDO9: No configuration
[ 86.828818] VDDQ_MMC1_3_1.8V: No configuration
[ 86.828851] VDDQ_MMC2_2.8V: No configuration
[ 86.828884] VDDQ_EXT_1.8V: No configuration
[ 86.828935] VDD_ALIVE_1.0V: No configuration
[ 86.839760] usb3503 0-0008: switched to STANDBY mode
[ 86.840336] wake enabled for irq 123
[ 86.855834] samsung-pinctrl 11000000.pinctrl: Setting external
wakeup interrupt mask: 0xfbfff7ff
[ 86.871661] Disabling non-boot CPUs ...
[ 87.016430] Enabling non-boot CPUs ...
[ 88.009557] CPU1: failed to boot: -110
[ 88.010324] Error taking CPU1 up: -110
[ 89.009841] CPU2: failed to boot: -110
[ 89.011290] Error taking CPU2 up: -110
[ 90.009615] CPU3: failed to boot: -110
[ 90.010258] Error taking CPU3 up: -110
[ 90.012152] s3c-i2c 13860000.i2c: slave address 0x00
[ 90.012174] s3c-i2c 13860000.i2c: bus frequency set to 390 KHz
[ 90.012208] s3c-i2c 13870000.i2c: slave address 0x00
[ 90.012225] s3c-i2c 13870000.i2c: bus frequency set to 97 KHz
[ 90.012257] s3c-i2c 13880000.i2c: slave address 0x00
[ 90.012274] s3c-i2c 13880000.i2c: bus frequency set to 97 KHz
[ 90.012306] s3c-i2c 138e0000.i2c: slave address 0x00
[ 90.012323] s3c-i2c 138e0000.i2c: bus frequency set to 97 KHz
[ 90.028694] s3c-rtc 10070000.rtc: rtc disabled, re-enabling
[ 90.029174] usb usb1: root hub lost power or was reset
[ 90.032911] s3c2410-wdt 10060000.watchdog: watchdog disabled
[ 90.033064] wake disabled for irq 123
[ 90.041886] usb3503 0-0008: switched to HUB mode
[ 90.127583] wake disabled for irq 119
[ 90.127865] dwc2 12480000.hsotg: resuming usb gadget g_ether
[ 90.429505] usb 1-2: reset high-speed USB device number 2 using exynos-ehci
[ 90.781458] usb 1-3: reset high-speed USB device number 3 using exynos-ehci
[ 91.366725] OOM killer enabled.
[ 91.369869] Restarting tasks ... done.
[ 91.419515] PM: suspend exit
# [ 92.229649] smsc95xx 1-2:1.0 eth0: link up, 100Mbps, full-duplex,
lpa 0xC5E1
# lscpu
Architecture: armv7l
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0
Off-line CPU(s) list: 1-3
Thread(s) per core: 1
Core(s) per socket: 1
Socket(s): 1
Vendor ID: ARM
Model: 0
Model name: Cortex-A9
Stepping: r3p0
CPU max MHz: 1704.0000
CPU min MHz: 200.0000
BogoMIPS: 24.00
Flags: half thumb fastmult vfp edsp neon vfpv3 tls vfpd32

Best Regards
-Anand