mbox series

[0/3] Add syscon-reboot and syscon-poweroff support for gs101/Pixel 6

Message ID 20240626194300.302327-1-peter.griffin@linaro.org
Headers show
Series Add syscon-reboot and syscon-poweroff support for gs101/Pixel 6 | expand

Message

Peter Griffin June 26, 2024, 7:42 p.m. UTC
Hi Krzysztof,

This series adds support for syscon-reboot and syscon-poweroff to gs101/Oriole.
It has been tested with reboot and poweroff commands respectively.

Note the syscon-reboot/poweroff has *runtime* dependencies on the exynos-pmu
and clk-gs101 patches in this series, as well as [1] which was just queued by
Lee. As you are the maintainer for exynos-pmu and samsung clock drivers I've
included those patches in this series.

For the moment I have left out syscon-reboot-mode dt node as whilst it uses the
same SYSIP_DAT0 register as exynosautov9, and setting this the reboot mode is
correctly reported in the Pixel bootloader. The bootloader is also checking a
scratch register in max77779 chip that isn't currently enabled upstream, and
thus the bootloader doesn't actually enter fastboot.

Kind regards,

Peter

[1] https://lore.kernel.org/linux-arm-kernel/20240621115544.1655458-1-peter.griffin@linaro.org/

Peter Griffin (3):
  arm64: dts: exynos: gs101: add syscon-poweroff and syscon-reboot nodes
  soc: samsung: exynos-pmu: add support for PMU_ALIVE non atomic
    registers
  clk: samsung: gs101: mark gout_hsi2_ufs_embd_i_clk_unipro as critical

 arch/arm64/boot/dts/exynos/google/gs101.dtsi | 15 +++++++++++++++
 drivers/clk/samsung/clk-gs101.c              |  2 +-
 drivers/soc/samsung/exynos-pmu.c             | 16 ++++++++++++++--
 include/linux/soc/samsung/exynos-regs-pmu.h  |  4 ++++
 4 files changed, 34 insertions(+), 3 deletions(-)

Comments

Krzysztof Kozlowski June 27, 2024, 10:47 a.m. UTC | #1
On 26/06/2024 21:42, Peter Griffin wrote:
> Hi Krzysztof,
> 
> This series adds support for syscon-reboot and syscon-poweroff to gs101/Oriole.
> It has been tested with reboot and poweroff commands respectively.
> 
> Note the syscon-reboot/poweroff has *runtime* dependencies on the exynos-pmu

How does the runtime dependency manifests? Something get broken if there
are no dependencies? Or maybe reboot does not work, but probably it did
not work before, either?

Best regards,
Krzysztof
Peter Griffin June 27, 2024, 12:10 p.m. UTC | #2
Hi Krzysztof,

On Thu, 27 Jun 2024 at 11:47, Krzysztof Kozlowski <krzk@kernel.org> wrote:
>
> On 26/06/2024 21:42, Peter Griffin wrote:
> > Hi Krzysztof,
> >
> > This series adds support for syscon-reboot and syscon-poweroff to gs101/Oriole.
> > It has been tested with reboot and poweroff commands respectively.
> >
> > Note the syscon-reboot/poweroff has *runtime* dependencies on the exynos-pmu
>
> How does the runtime dependency manifests? Something get broken if there
> are no dependencies? Or maybe reboot does not work, but probably it did
> not work before, either?

Without [1] but with this series applied you will get an Serror
interrupt and hang on poweroff, and reboot commands, as it will use a
mmio syscon to write the protected register.

[   74.680240][    T1] reboot: Restarting system
[   74.680322][    C0] SError Interrupt on CPU0, code
0x00000000be000011 -- SError
[   74.680329][    C0] CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted
6.10.0-rc3-next-20240613-00009-g6ca503bd3c2b #476
[   74.680336][    C0] Hardware name: Oriole (DT)
[   74.680338][    C0] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT
-SSBS BTYPE=--)
[   74.680345][    C0] pc : _raw_spin_unlock_irqrestore+0x10/0x44
[   74.680363][    C0] lr : regmap_unlock_spinlock+0x14/0x20
[   74.680373][    C0] sp : ffff80008009bb40
[   74.680375][    C0] x29: ffff80008009bb40 x28: ffff00da4587e158
x27: ffffa38d3bc74708
[   74.680386][    C0] x26: ffffa38d3d9c9ca8 x25: 0000000000000000
x24: 0000000000000000
[   74.680394][    C0] x23: 0000000000000000 x22: 0000000000000002
x21: 0000000000000002
[   74.680400][    C0] x20: 0000000000003a00 x19: 0000000000000000
x18: ffffffffffffffff
[   74.680407][    C0] x17: 0000000000000000 x16: ffffa38d3c6cf438
x15: ffff80008009b6a0
[   74.680414][    C0] x14: 0000000000000000 x13: ffff00dbb6980000
x12: 00000000000007d4
[   74.680421][    C0] x11: 000000000000029c x10: ffff00dbb6c40000 x9
: ffff00dbb6980000
[   74.680427][    C0] x8 : ffff80008009bc28 x7 : 0000000000000000 x6
: 0000000000000000
[   74.680434][    C0] x5 : ffffa38d3b83e074 x4 : 0000000000003a00 x3
: 0000000000000000
[   74.680440][    C0] x2 : ffffa38d3b831764 x1 : ffff00da40230000 x0
: 0000000100000001
[   74.680447][    C0] Kernel panic - not syncing: Asynchronous SError Interrupt

and

[   49.448590][    T1] reboot: Power down
[   49.448747][    C0] SError Interrupt on CPU0, code
0x00000000be000011 -- SError
[..]

Without the clk-gs101 critical clock change, poweroff command will
hang, when shutting down UFS.

Without the exynos-pmu support for !atomic registers, the reboot
command won't work when the DT is present as the register write to
SYSTEM_CONFIGURATION register will fail.

[  114.525217][    T1] reboot: Restarting system
[  114.525290][    T1] tensor_sec_reg_write(): SMC failed: -22
[  115.525434][    T1] Unable to restart system
[  116.025576][    T1] Reboot failed -- System halted

For poweroff, you are correct this has not been supported on Pixel 6
so far upstream.

However `echo b > /proc/sysrq-trigger ` has worked in previous kernel
releases (it would reset the system using Watchdog). With the
syscon-reboot DT present, but without [1] this will cause a Serror and
no longer restart the system which would be a regression.

Thanks,

Peter.

[1] https://lore.kernel.org/linux-arm-kernel/20240621115544.1655458-1-peter.griffin@linaro.org/
Krzysztof Kozlowski July 1, 2024, 8:14 a.m. UTC | #3
On 27/06/2024 14:10, Peter Griffin wrote:
> Hi Krzysztof,
> 
> On Thu, 27 Jun 2024 at 11:47, Krzysztof Kozlowski <krzk@kernel.org> wrote:
>>
>> On 26/06/2024 21:42, Peter Griffin wrote:
>>> Hi Krzysztof,
>>>
>>> This series adds support for syscon-reboot and syscon-poweroff to gs101/Oriole.
>>> It has been tested with reboot and poweroff commands respectively.
>>>
>>> Note the syscon-reboot/poweroff has *runtime* dependencies on the exynos-pmu
>>
>> How does the runtime dependency manifests? Something get broken if there
>> are no dependencies? Or maybe reboot does not work, but probably it did
>> not work before, either?
> 
> Without [1] but with this series applied you will get an Serror
> interrupt and hang on poweroff, and reboot commands, as it will use a
> mmio syscon to write the protected register.
> 
> [   74.680240][    T1] reboot: Restarting system
> [   74.680322][    C0] SError Interrupt on CPU0, code
> 0x00000000be000011 -- SError
> [   74.680329][    C0] CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted
> 6.10.0-rc3-next-20240613-00009-g6ca503bd3c2b #476
> [   74.680336][    C0] Hardware name: Oriole (DT)
> [   74.680338][    C0] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT
> -SSBS BTYPE=--)
> [   74.680345][    C0] pc : _raw_spin_unlock_irqrestore+0x10/0x44
> [   74.680363][    C0] lr : regmap_unlock_spinlock+0x14/0x20
> [   74.680373][    C0] sp : ffff80008009bb40
> [   74.680375][    C0] x29: ffff80008009bb40 x28: ffff00da4587e158
> x27: ffffa38d3bc74708
> [   74.680386][    C0] x26: ffffa38d3d9c9ca8 x25: 0000000000000000
> x24: 0000000000000000
> [   74.680394][    C0] x23: 0000000000000000 x22: 0000000000000002
> x21: 0000000000000002
> [   74.680400][    C0] x20: 0000000000003a00 x19: 0000000000000000
> x18: ffffffffffffffff
> [   74.680407][    C0] x17: 0000000000000000 x16: ffffa38d3c6cf438
> x15: ffff80008009b6a0
> [   74.680414][    C0] x14: 0000000000000000 x13: ffff00dbb6980000
> x12: 00000000000007d4
> [   74.680421][    C0] x11: 000000000000029c x10: ffff00dbb6c40000 x9
> : ffff00dbb6980000
> [   74.680427][    C0] x8 : ffff80008009bc28 x7 : 0000000000000000 x6
> : 0000000000000000
> [   74.680434][    C0] x5 : ffffa38d3b83e074 x4 : 0000000000003a00 x3
> : 0000000000000000
> [   74.680440][    C0] x2 : ffffa38d3b831764 x1 : ffff00da40230000 x0
> : 0000000100000001
> [   74.680447][    C0] Kernel panic - not syncing: Asynchronous SError Interrupt
> 
> and
> 
> [   49.448590][    T1] reboot: Power down
> [   49.448747][    C0] SError Interrupt on CPU0, code
> 0x00000000be000011 -- SError
> [..]
> 
> Without the clk-gs101 critical clock change, poweroff command will
> hang, when shutting down UFS.
> 
> Without the exynos-pmu support for !atomic registers, the reboot
> command won't work when the DT is present as the register write to
> SYSTEM_CONFIGURATION register will fail.
> 
> [  114.525217][    T1] reboot: Restarting system
> [  114.525290][    T1] tensor_sec_reg_write(): SMC failed: -22
> [  115.525434][    T1] Unable to restart system
> [  116.025576][    T1] Reboot failed -- System halted
> 
> For poweroff, you are correct this has not been supported on Pixel 6
> so far upstream.
> 
> However `echo b > /proc/sysrq-trigger ` has worked in previous kernel
> releases (it would reset the system using Watchdog). With the
> syscon-reboot DT present, but without [1] this will cause a Serror and
> no longer restart the system which would be a regression.

Thanks, DTS will wait for the next cycle then.

Best regards,
Krzysztof