[PATCH] rtw88: pci: Power cycle device during shutdown

[PATCH] rtw88: pci: Power cycle device during shutdown

[Kai-Heng Feng]

Sometimes system freeze on cold/warm boot when rtw88 is probing.

According to [1], platform firmware may not properly power manage the
device during shutdown. I did some expirements and putting the device to
D3 can workaround the issue.

So let's power cycle the device by putting the device to D3 at shutdown
to prevent the issue from happening.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=206411#c9

Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
 drivers/net/wireless/realtek/rtw88/pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c
index 3413973bc475..7f1f5073b9f4 100644
--- a/drivers/net/wireless/realtek/rtw88/pci.c
+++ b/drivers/net/wireless/realtek/rtw88/pci.c
@@ -1599,6 +1599,8 @@ void rtw_pci_shutdown(struct pci_dev *pdev)
 
 	if (chip->ops->shutdown)
 		chip->ops->shutdown(rtwdev);
+
+	pci_set_power_state(pdev, PCI_D3hot);
 }
 EXPORT_SYMBOL(rtw_pci_shutdown);
 
-- 
2.17.1

Re: [PATCH] rtw88: pci: Power cycle device during shutdown

[Brian Norris]

On Mon, Aug 24, 2020 at 2:32 AM Kai-Heng Feng
<kai.heng.feng@canonical.com> wrote:
>
> Sometimes system freeze on cold/warm boot when rtw88 is probing.
>
> According to [1], platform firmware may not properly power manage the
> device during shutdown. I did some expirements and putting the device to
> D3 can workaround the issue.
>
> So let's power cycle the device by putting the device to D3 at shutdown
> to prevent the issue from happening.
>
> [1] https://bugzilla.kernel.org/show_bug.cgi?id=206411#c9
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Can you at least include some more details, like which hardware
version and firmware? And which platform? It seems a bit harsh to
include a platform workaround to run for everyone, unless there's
truly no downside. But even then, it's good to log what you're working
with, in case there are ever problems with this in the future.

Brian

Re: [PATCH] rtw88: pci: Power cycle device during shutdown

[Kai-Heng Feng]

> On Aug 26, 2020, at 08:27, Brian Norris <briannorris@chromium.org> wrote:
> 
> On Mon, Aug 24, 2020 at 2:32 AM Kai-Heng Feng
> <kai.heng.feng@canonical.com> wrote:
>> 
>> Sometimes system freeze on cold/warm boot when rtw88 is probing.
>> 
>> According to [1], platform firmware may not properly power manage the
>> device during shutdown. I did some expirements and putting the device to
>> D3 can workaround the issue.
>> 
>> So let's power cycle the device by putting the device to D3 at shutdown
>> to prevent the issue from happening.
>> 
>> [1] https://bugzilla.kernel.org/show_bug.cgi?id=206411#c9
>> 
>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> 
> Can you at least include some more details, like which hardware
> version and firmware?

8723DE, 8822BE and 8822CE are affected [1].

> And which platform?

Many x86 laptops.

Some users claim BIOS update can fix the issue, however some are still affected.

> It seems a bit harsh to
> include a platform workaround to run for everyone, unless there's
> truly no downside. But even then, it's good to log what you're working
> with, in case there are ever problems with this in the future.

Ok. I can send V2 with more detailed commit message.

[1] https://bugs.launchpad.net/bugs/1872984

Kai-Heng

> 
> Brian

[PATCH v2] rtw88: pci: Power cycle device during shutdown

[Kai-Heng Feng]

There are reports that 8822CE fails to work rtw88 with "failed to read DBI
register" error. Also I have a system with 8723DE which freezes the whole
system when the rtw88 is probing the device.

According to [1], platform firmware may not properly power manage the
device during shutdown. I did some expirements and putting the device to
D3 can workaround the issue.

So let's power cycle the device by putting the device to D3 at shutdown
to prevent the issue from happening.

[1] https://bugzilla.kernel.org/show_bug.cgi?id=206411#c9

BugLink: https://bugs.launchpad.net/bugs/1872984
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v2:
 - Add more detail in commit log.

 drivers/net/wireless/realtek/rtw88/pci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtw88/pci.c b/drivers/net/wireless/realtek/rtw88/pci.c
index 3413973bc475..7f1f5073b9f4 100644
--- a/drivers/net/wireless/realtek/rtw88/pci.c
+++ b/drivers/net/wireless/realtek/rtw88/pci.c
@@ -1599,6 +1599,8 @@ void rtw_pci_shutdown(struct pci_dev *pdev)
 
 	if (chip->ops->shutdown)
 		chip->ops->shutdown(rtwdev);
+
+	pci_set_power_state(pdev, PCI_D3hot);
 }
 EXPORT_SYMBOL(rtw_pci_shutdown);
 
-- 
2.17.1

Re: [PATCH v2] rtw88: pci: Power cycle device during shutdown

[Kalle Valo]

Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:

> There are reports that 8822CE fails to work rtw88 with "failed to read DBI
> register" error. Also I have a system with 8723DE which freezes the whole
> system when the rtw88 is probing the device.
> 
> According to [1], platform firmware may not properly power manage the
> device during shutdown. I did some expirements and putting the device to
> D3 can workaround the issue.
> 
> So let's power cycle the device by putting the device to D3 at shutdown
> to prevent the issue from happening.
> 
> [1] https://bugzilla.kernel.org/show_bug.cgi?id=206411#c9
> 
> BugLink: https://bugs.launchpad.net/bugs/1872984
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Patch applied to wireless-drivers-next.git, thanks.

44492e70adc8 rtw88: pci: Power cycle device during shutdown

-- 
https://patchwork.kernel.org/patch/11804271/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches