Re: [PATCH] mfd / platform: cros_ec: Query EC protocol version if EC transitions between RO/RW

From: Fabien Lahoudere
Date: Mon Jan 20 2020 - 06:16:14 EST


Hi Yicheng,

Thanks for your quick answer.

I updated the firmware after my first email on friday.
Now the version is correct:

# ectool version --name=cros_fp
RO version: nocturne_fp_v2.2.64-58cf5974e
RW version: nocturne_fp_v2.2.191-1d529566e
Firmware copy: RW
Build info: nocturne_fp_v2.2.191-1d529566e 2019-11-01 20:30:58
@chromeos-ci-legacy-us-central1-b-x32-72-dltd
Tool version: v2.0.3031-9e0f24fad 2020-01-13 06:11:02 @chromeos-ci-
legacy-us-east1-d-x32-89-i09h

The result does not change. This is the console output after I sent the
reboot command.

$ ectool name=cros_fp output
...
[250664.176204 HC 0xa9]
[250664.176287 HC 0xa9 err 1]
[250664.177413 HC 0x67]
[250664.177489 HC 0x67 err 9]
[250664.178434 HC 0x02]
[250664.180308 HC Suppressed: 0x97=127 0x98=138 0x115=0]
[250664.477987 HC 0x01]
[250892.898421 HC 0x02]
[250892.900447 HC 0x07]
[250892.901286 HC 0x0b]
[250902.139053 HC 0x02]
[250902.141059 HC 0x07]
[250902.141847 HC 0x0b]
[250902.142988 HC 0xd2]
[250902.143072 Executing host reboot command 1]
[250902.143176 HC 0xd2 err 4]
[250908.838254 HC 0x02]
[250908.840474 HC 0x07]
[250908.841391 HC 0x0b]

it seems we have an error when executing the 0zd2 command.

Any idea what is error 4?

Thanks

Fabien

Le jeudi 16 janvier 2020 Ã 05:04 -0800, Yicheng Li a Ãcrit :
> Hi Fabien,
>
> First, you need the new firmware which has RW 2.2.191 instead of
> 2.2.110. It's available in release M80. The old firmware you were
> using does not have the RO/RW protocol incompatibility problem
> because RW 2.2.110 still only support versions 0 and 1 of
> EC_CMD_GET_NEXT_EVENT, same as RO 2.2.64. RW 2.2.191 has version 2 of
> EC_CMD_GET_NEXT_ EVENT, hence the issue described in the commit
> message.
>
> With RW 2.2.191, if the kernal does not have this patch, rebooting
> cros_fp will leave you in an infinite loop in RO, as described in the
> commit message. This patch solves the problem and you should be in RW
> after the reboot. You can see more details on the commands sent to
> cros_fp during RO if you have cros_fp.log
>
> Let me know if you have other questions. Thanks!
>
> Best,
> Yicheng
>
>
> On Thu, Jan 16, 2020, 4:27 AM Fabien Lahoudere <
> fabien.lahoudere@xxxxxxxxxxxxx> wrote:
> > Hi,
> >
> > I tried to test that patch but I cannot switch to RO firmware.
> > I do the following steps:
> >
> > root@debian:/sys/class/chromeos/cros_fp# cat version
> > RO version: nocturne_fp_v2.2.64-58cf5974e
> > RW version: nocturne_fp_v2.2.110-b936c0a3c
> > Firmware copy: RW
> > Build info: nocturne_fp_v2.2.110-b936c0a3c 2018-11-02 14:16:46
> > @swarm-cros-461
> > Chip vendor: stm
> > Chip name: stm32h7x3
> > Chip revision:
> > Board version: EC error 1
> > root@debian:/sys/class/chromeos/cros_fp# echo ro > reboot
> > root@debian:/sys/class/chromeos/cros_fp# cat version
> > RO version: nocturne_fp_v2.2.64-58cf5974e
> > RW version: nocturne_fp_v2.2.110-b936c0a3c
> > Firmware copy: RW
> > Build info: nocturne_fp_v2.2.110-b936c0a3c 2018-11-02 14:16:46
> > @swarm-cros-461
> > Chip vendor: stm
> > Chip name: stm32h7x3
> > Chip revision:
> > Board version: EC error 1
> > root@debian:/sys/class/chromeos/cros_fp#
> >
> > We see here that cros_fp is still RW.
> >
> > I also tried with:
> >
> > debian@debian:/src/ec$ sudo build/bds/util/ectool --name=cros_fp
> > reboot_ec RO
> > debian@debian:/src/ec$ sudo build/bds/util/ectool --name=cros_fp
> > version
> > RO version: nocturne_fp_v2.2.64-58cf5974e
> > RW version: nocturne_fp_v2.2.110-b936c0a3c
> > Firmware copy: RW
> > Build info: nocturne_fp_v2.2.110-b936c0a3c 2018-11-02 14:16:46
> > @swarm-cros-461
> > Tool version: v2.0.3074-a5052d4e7 2020-01-16 10:23:05
> > debian@debian
> > debian@debian:/src/ec$
> >
> > with the same result.
> >
> > Can you decribe us steps you follow to test that patch?
> >
> > Thanks
> >
> > Fabien
> >
> > Le lundi 18 novembre 2019 Ã 12:00 -0800, Yicheng Li a Ãcrit :
> > > RO and RW of EC may have different EC protocol version. If EC
> > > transitions
> > > between RO and RW, but AP does not reboot (this is true for
> > > fingerprint
> > > microcontroller / cros_fp, but not true for main ec / cros_ec),
> > the
> > > AP
> > > still uses the protocol version queried before transition, which
> > can
> > > cause problems. In the case of fingerprint microcontroller, this
> > > causes
> > > AP to send the wrong version of EC_CMD_GET_NEXT_EVENT to RO in
> > the
> > > interrupt handler, which in turn prevents RO to clear the
> > interrupt
> > > line to AP, in an infinite loop.
> > >
> > > Once an EC_HOST_EVENT_INTERFACE_READY is received, we know that
> > there
> > > might have been a transition between RO and RW, so re-query the
> > > protocol.
> > >
> > > Signed-off-by: Yicheng Li <yichengli@xxxxxxxxxxxx>
> > >
> > > Change-Id: Ib58032ff4a8e113bdbd07212e8aff42807afff38
> > > Series-to: LKML <linux-kernel@xxxxxxxxxxxxxxx>
> > > Series-cc: Benson Leung <bleung@xxxxxxxxxxxx>, Enric Balletbo i
> > Serra
> > > <enric.balletbo@xxxxxxxxxxxxx>, Gwendal Grignou <
> > gwendal@xxxxxxxxxxxx
> > > >
> > > ---
> > > drivers/platform/chrome/cros_ec.c | 24
> > > +++++++++++++++++++++
> > > include/linux/platform_data/cros_ec_proto.h | 1 +
> > > 2 files changed, 25 insertions(+)
> > >
> > > diff --git a/drivers/platform/chrome/cros_ec.c
> > > b/drivers/platform/chrome/cros_ec.c
> > > index 9b2d07422e17..0c910846d99d 100644
> > > --- a/drivers/platform/chrome/cros_ec.c
> > > +++ b/drivers/platform/chrome/cros_ec.c
> > > @@ -104,6 +104,23 @@ static int cros_ec_sleep_event(struct
> > > cros_ec_device *ec_dev, u8 sleep_event)
> > > return ret;
> > > }
> > >
> > > +static int cros_ec_ready_event(struct notifier_block *nb,
> > > + unsigned long queued_during_suspend, void *_notify)
> > > +{
> > > + struct cros_ec_device *ec_dev = container_of(nb, struct
> > > cros_ec_device,
> > > +
> > notifier_ready);
> > > + u32 host_event = cros_ec_get_host_event(ec_dev);
> > > +
> > > + if (host_event &
> > > EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) {
> > > + mutex_lock(&ec_dev->lock);
> > > + cros_ec_query_all(ec_dev);
> > > + mutex_unlock(&ec_dev->lock);
> > > + return NOTIFY_OK;
> > > + } else {
> > > + return NOTIFY_DONE;
> > > + }
> > > +}
> > > +
> > > /**
> > > * cros_ec_register() - Register a new ChromeOS EC, using the
> > > provided info.
> > > * @ec_dev: Device to register.
> > > @@ -201,6 +218,13 @@ int cros_ec_register(struct cros_ec_device
> > > *ec_dev)
> > > dev_dbg(ec_dev->dev, "Error %d clearing sleep event
> > to
> > > ec",
> > > err);
> > >
> > > + /* Register the notifier for EC_HOST_EVENT_INTERFACE_READY
> > > event. */
> > > + ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
> > > + err = blocking_notifier_chain_register(&ec_dev-
> > >event_notifier,
> > > + &ec_dev-
> > > >notifier_ready);
> > > + if (err < 0)
> > > + dev_warn(ec_dev->dev, "Failed to register
> > notifier\n");
> > > +
> > > dev_info(dev, "Chrome EC device registered\n");
> > >
> > > return 0;
> > > diff --git a/include/linux/platform_data/cros_ec_proto.h
> > > b/include/linux/platform_data/cros_ec_proto.h
> > > index 0d4e4aaed37a..9840408c0b01 100644
> > > --- a/include/linux/platform_data/cros_ec_proto.h
> > > +++ b/include/linux/platform_data/cros_ec_proto.h
> > > @@ -161,6 +161,7 @@ struct cros_ec_device {
> > > int event_size;
> > > u32 host_event_wake_mask;
> > > u32 last_resume_result;
> > > + struct notifier_block notifier_ready;
> > >
> > > /* The platform devices used by the mfd driver */
> > > struct platform_device *ec;
> >