[PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Sasha Levin]

From: Stephen Boyd <swboyd@chromium.org>

[ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]

On some platforms, the TPM power is managed by firmware and therefore we
don't need to stop the TPM on suspend when going to a light version of
suspend such as S0ix ("freeze" suspend state). Add a chip flag,
TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
platforms can probe for the usage of this light suspend and avoid
touching the TPM state across suspend/resume.

Cc: Andrey Pronin <apronin@chromium.org>
Cc: Duncan Laurie <dlaurie@chromium.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Alexander Steffen <Alexander.Steffen@infineon.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/char/tpm/tpm-interface.c | 8 +++++++-
 drivers/char/tpm/tpm.h           | 1 +
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index d7a3888ad80f0..7f105490604c8 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/spinlock.h>
+#include <linux/suspend.h>
 #include <linux/freezer.h>
 #include <linux/tpm_eventlog.h>
 
@@ -394,7 +395,11 @@ int tpm_pm_suspend(struct device *dev)
 		return -ENODEV;
 
 	if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
-		return 0;
+		goto suspended;
+
+	if ((chip->flags & TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED) &&
+	    !pm_suspend_via_firmware())
+		goto suspended;
 
 	if (!tpm_chip_start(chip)) {
 		if (chip->flags & TPM_CHIP_FLAG_TPM2)
@@ -405,6 +410,7 @@ int tpm_pm_suspend(struct device *dev)
 		tpm_chip_stop(chip);
 	}
 
+suspended:
 	return rc;
 }
 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index a7fea3e0ca86a..f3bf2f7f755c8 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -162,6 +162,7 @@ enum tpm_chip_flags {
 	TPM_CHIP_FLAG_VIRTUAL		= BIT(3),
 	TPM_CHIP_FLAG_HAVE_TIMEOUTS	= BIT(4),
 	TPM_CHIP_FLAG_ALWAYS_POWERED	= BIT(5),
+	TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED	= BIT(6),
 };
 
 #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
-- 
2.20.1

Re: [PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Guenter Roeck]

On Tue, Dec 10, 2019 at 1:12 PM Sasha Levin <sashal@kernel.org> wrote:
>
> From: Stephen Boyd <swboyd@chromium.org>
>
> [ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]
>
> On some platforms, the TPM power is managed by firmware and therefore we
> don't need to stop the TPM on suspend when going to a light version of
> suspend such as S0ix ("freeze" suspend state). Add a chip flag,
> TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
> platforms can probe for the usage of this light suspend and avoid
> touching the TPM state across suspend/resume.
>

Are the patches needed to support CR50 (which need this patch) going
to be applied to v5.4.y as well ? If not, what is the purpose of
applying this patch to v5.4.y ?

Thanks,
Guenter

> Cc: Andrey Pronin <apronin@chromium.org>
> Cc: Duncan Laurie <dlaurie@chromium.org>
> Cc: Jason Gunthorpe <jgg@ziepe.ca>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Guenter Roeck <groeck@chromium.org>
> Cc: Alexander Steffen <Alexander.Steffen@infineon.com>
> Cc: Heiko Stuebner <heiko@sntech.de>
> Tested-by: Heiko Stuebner <heiko@sntech.de>
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/char/tpm/tpm-interface.c | 8 +++++++-
>  drivers/char/tpm/tpm.h           | 1 +
>  2 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index d7a3888ad80f0..7f105490604c8 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -23,6 +23,7 @@
>  #include <linux/slab.h>
>  #include <linux/mutex.h>
>  #include <linux/spinlock.h>
> +#include <linux/suspend.h>
>  #include <linux/freezer.h>
>  #include <linux/tpm_eventlog.h>
>
> @@ -394,7 +395,11 @@ int tpm_pm_suspend(struct device *dev)
>                 return -ENODEV;
>
>         if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
> -               return 0;
> +               goto suspended;
> +
> +       if ((chip->flags & TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED) &&
> +           !pm_suspend_via_firmware())
> +               goto suspended;
>
>         if (!tpm_chip_start(chip)) {
>                 if (chip->flags & TPM_CHIP_FLAG_TPM2)
> @@ -405,6 +410,7 @@ int tpm_pm_suspend(struct device *dev)
>                 tpm_chip_stop(chip);
>         }
>
> +suspended:
>         return rc;
>  }
>  EXPORT_SYMBOL_GPL(tpm_pm_suspend);
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index a7fea3e0ca86a..f3bf2f7f755c8 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -162,6 +162,7 @@ enum tpm_chip_flags {
>         TPM_CHIP_FLAG_VIRTUAL           = BIT(3),
>         TPM_CHIP_FLAG_HAVE_TIMEOUTS     = BIT(4),
>         TPM_CHIP_FLAG_ALWAYS_POWERED    = BIT(5),
> +       TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED    = BIT(6),
>  };
>
>  #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
> --
> 2.20.1
>

Re: [PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Jarkko Sakkinen]

On Tue, Dec 10, 2019 at 01:32:15PM -0800, Guenter Roeck wrote:
> On Tue, Dec 10, 2019 at 1:12 PM Sasha Levin <sashal@kernel.org> wrote:
> >
> > From: Stephen Boyd <swboyd@chromium.org>
> >
> > [ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]
> >
> > On some platforms, the TPM power is managed by firmware and therefore we
> > don't need to stop the TPM on suspend when going to a light version of
> > suspend such as S0ix ("freeze" suspend state). Add a chip flag,
> > TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
> > platforms can probe for the usage of this light suspend and avoid
> > touching the TPM state across suspend/resume.
> >
> 
> Are the patches needed to support CR50 (which need this patch) going
> to be applied to v5.4.y as well ? If not, what is the purpose of
> applying this patch to v5.4.y ?
> 
> Thanks,
> Guenter

Thanks Guenter. I think not.

/Jarkko

Re: [PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Guenter Roeck]

On Wed, Dec 11, 2019 at 9:57 AM Jarkko Sakkinen
<jarkko.sakkinen@linux.intel.com> wrote:
>
> On Tue, Dec 10, 2019 at 01:32:15PM -0800, Guenter Roeck wrote:
> > On Tue, Dec 10, 2019 at 1:12 PM Sasha Levin <sashal@kernel.org> wrote:
> > >
> > > From: Stephen Boyd <swboyd@chromium.org>
> > >
> > > [ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]
> > >
> > > On some platforms, the TPM power is managed by firmware and therefore we
> > > don't need to stop the TPM on suspend when going to a light version of
> > > suspend such as S0ix ("freeze" suspend state). Add a chip flag,
> > > TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
> > > platforms can probe for the usage of this light suspend and avoid
> > > touching the TPM state across suspend/resume.
> > >
> >
> > Are the patches needed to support CR50 (which need this patch) going
> > to be applied to v5.4.y as well ? If not, what is the purpose of
> > applying this patch to v5.4.y ?
> >
> > Thanks,
> > Guenter
>
> Thanks Guenter. I think not.
>
Thought so. In that case this patch should be dropped.

Guenter

Re: [PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Jarkko Sakkinen]

On Wed, Dec 11, 2019 at 10:05:52AM -0800, Guenter Roeck wrote:
> On Wed, Dec 11, 2019 at 9:57 AM Jarkko Sakkinen
> <jarkko.sakkinen@linux.intel.com> wrote:
> >
> > On Tue, Dec 10, 2019 at 01:32:15PM -0800, Guenter Roeck wrote:
> > > On Tue, Dec 10, 2019 at 1:12 PM Sasha Levin <sashal@kernel.org> wrote:
> > > >
> > > > From: Stephen Boyd <swboyd@chromium.org>
> > > >
> > > > [ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]
> > > >
> > > > On some platforms, the TPM power is managed by firmware and therefore we
> > > > don't need to stop the TPM on suspend when going to a light version of
> > > > suspend such as S0ix ("freeze" suspend state). Add a chip flag,
> > > > TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
> > > > platforms can probe for the usage of this light suspend and avoid
> > > > touching the TPM state across suspend/resume.
> > > >
> > >
> > > Are the patches needed to support CR50 (which need this patch) going
> > > to be applied to v5.4.y as well ? If not, what is the purpose of
> > > applying this patch to v5.4.y ?
> > >
> > > Thanks,
> > > Guenter
> >
> > Thanks Guenter. I think not.
> >
> Thought so. In that case this patch should be dropped.
> 
> Guenter

I fully agree with you.

/Jarkko

Re: [PATCH AUTOSEL 5.4 277/350] tpm: Add a flag to indicate TPM power is managed by firmware

[Sasha Levin]

On Fri, Dec 13, 2019 at 02:17:31AM +0200, Jarkko Sakkinen wrote:
>On Wed, Dec 11, 2019 at 10:05:52AM -0800, Guenter Roeck wrote:
>> On Wed, Dec 11, 2019 at 9:57 AM Jarkko Sakkinen
>> <jarkko.sakkinen@linux.intel.com> wrote:
>> >
>> > On Tue, Dec 10, 2019 at 01:32:15PM -0800, Guenter Roeck wrote:
>> > > On Tue, Dec 10, 2019 at 1:12 PM Sasha Levin <sashal@kernel.org> wrote:
>> > > >
>> > > > From: Stephen Boyd <swboyd@chromium.org>
>> > > >
>> > > > [ Upstream commit 2e2ee5a2db06c4b81315514b01d06fe5644342e9 ]
>> > > >
>> > > > On some platforms, the TPM power is managed by firmware and therefore we
>> > > > don't need to stop the TPM on suspend when going to a light version of
>> > > > suspend such as S0ix ("freeze" suspend state). Add a chip flag,
>> > > > TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED, to indicate this so that certain
>> > > > platforms can probe for the usage of this light suspend and avoid
>> > > > touching the TPM state across suspend/resume.
>> > > >
>> > >
>> > > Are the patches needed to support CR50 (which need this patch) going
>> > > to be applied to v5.4.y as well ? If not, what is the purpose of
>> > > applying this patch to v5.4.y ?
>> > >
>> > > Thanks,
>> > > Guenter
>> >
>> > Thanks Guenter. I think not.
>> >
>> Thought so. In that case this patch should be dropped.
>>
>> Guenter
>
>I fully agree with you.

I've dropped it, thanks!

-- 
Thanks,
Sasha