Re: Aw: Re: Re: [PATCH 09/13] PCI: mediatek: Advertise lack of MSI handling

2021-03-02 Thread Robin Murphy

On 2021-03-01 14:06, Frank Wunderlich wrote:

Gesendet: Montag, 01. März 2021 um 14:31 Uhr
Von: "Marc Zyngier" 

Frank,


i guess it's a bug in ath10k driver or my r64 board (it is a v1.1
which has missing capacitors on tx lines).


No, this definitely looks like a bug in the MTK PCIe driver,
where the mutex is either not properly initialised, corrupted,
or the wrong pointer is passed.


but why does it happen only with the ath10k-card and not the mt7612 in
same slot?


Does mt7612 use MSI? What we have here is a bogus mutex in the
MTK PCIe driver, and the only way not to get there would be
to avoid using MSIs.


i guess this card/its driver does not use MSI. Did not found anything in 
"datasheet" [1] or driver [2] about msi


FWIW, no need to guess - `lspci -v` (as root) should tell you whether 
the card has MSI (and/or MSI-X) capability, and whether it is enabled if so.


Robin.




This r64 machine is supposed to have working MSIs, right?


imho mt7622 have working MSI


Do you get the same issue without this series?


tested 5.11.0 [1] without this series (but with your/thomas' patch
from discussion about my old patch) and got same trace. so this series
does not break anything here.


Can you retest without any additional patch on top of 5.11?
These two patches only affect platforms that do *not* have MSIs at all.


i can revert these 2, but still need patches for mt7622 pcie-support [3]...btw. 
i see that i miss these in 5.11-main...do not see traceback with them (have 
firmware not installed...)

root@bpi-r64:~# dmesg | grep ath
[6.450765] ath10k_pci :01:00.0: assign IRQ: got 146
[6.661752] ath10k_pci :01:00.0: enabling device ( -> 0002)
[6.697811] ath10k_pci :01:00.0: enabling bus mastering
[6.721293] ath10k_pci :01:00.0: pci irq msi oper_irq_mode 2 irq_mode 0 r
eset_mode 0
[6.921030] ath10k_pci :01:00.0: Failed to find firmware-N.bin (N between
  2 and 6) from ath10k/QCA988X/hw2.0: -2
[6.931698] ath10k_pci :01:00.0: could not fetch firmware files (-2)
[6.940417] ath10k_pci :01:00.0: could not probe fw (-2)

so traceback was caused by missing changes in mtk pcie-driver not yet upstream, 
added Chuanjia Liu




Tried with an mt7612e, this seems to work without any errors.

so for mt7622/mt7623

Tested-by: Frank Wunderlich 


We definitely need to understand the above.


there is a hardware-bug which may cause this...afair i saw this with
the card in r64 with earlier Kernel-versions where other cards work
(like the mt7612e).


I don't think a HW bug affecting PCI would cause what we are seeing
here, unless it results in memory corruption.



[1] 
https://www.asiarf.com/shop/wifi-wlan/wifi_mini_pcie/ws2433-wifi-11ac-mini-pcie-module-manufacturer/
[2] grep -Rni 'msi' drivers/net/wireless/mediatek/mt76/mt76x2/
[3] https://patchwork.kernel.org/project/linux-mediatek/list/?series=372885

___
linux-arm-kernel mailing list
linux-arm-ker...@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel



Aw: Re: Re: [PATCH 09/13] PCI: mediatek: Advertise lack of MSI handling

2021-03-01 Thread Frank Wunderlich
> Gesendet: Montag, 01. März 2021 um 14:31 Uhr
> Von: "Marc Zyngier" 
>
> Frank,
> 
> >> > i guess it's a bug in ath10k driver or my r64 board (it is a v1.1
> >> > which has missing capacitors on tx lines).
> >> 
> >> No, this definitely looks like a bug in the MTK PCIe driver,
> >> where the mutex is either not properly initialised, corrupted,
> >> or the wrong pointer is passed.
> > 
> > but why does it happen only with the ath10k-card and not the mt7612 in
> > same slot?
> 
> Does mt7612 use MSI? What we have here is a bogus mutex in the
> MTK PCIe driver, and the only way not to get there would be
> to avoid using MSIs.

i guess this card/its driver does not use MSI. Did not found anything in 
"datasheet" [1] or driver [2] about msi

> > 
> >> This r64 machine is supposed to have working MSIs, right?
> > 
> > imho mt7622 have working MSI
> > 
> >> Do you get the same issue without this series?
> > 
> > tested 5.11.0 [1] without this series (but with your/thomas' patch
> > from discussion about my old patch) and got same trace. so this series
> > does not break anything here.
> 
> Can you retest without any additional patch on top of 5.11?
> These two patches only affect platforms that do *not* have MSIs at all.

i can revert these 2, but still need patches for mt7622 pcie-support [3]...btw. 
i see that i miss these in 5.11-main...do not see traceback with them (have 
firmware not installed...)

root@bpi-r64:~# dmesg | grep ath
[6.450765] ath10k_pci :01:00.0: assign IRQ: got 146 
[6.661752] ath10k_pci :01:00.0: enabling device ( -> 0002)  
[6.697811] ath10k_pci :01:00.0: enabling bus mastering  
[6.721293] ath10k_pci :01:00.0: pci irq msi oper_irq_mode 2 irq_mode 0 r
eset_mode 0 
[6.921030] ath10k_pci :01:00.0: Failed to find firmware-N.bin (N between
 2 and 6) from ath10k/QCA988X/hw2.0: -2 
[6.931698] ath10k_pci :01:00.0: could not fetch firmware files (-2) 
[6.940417] ath10k_pci :01:00.0: could not probe fw (-2)

so traceback was caused by missing changes in mtk pcie-driver not yet upstream, 
added Chuanjia Liu

> > 
> >> > Tried with an mt7612e, this seems to work without any errors.
> >> >
> >> > so for mt7622/mt7623
> >> >
> >> > Tested-by: Frank Wunderlich 
> >> 
> >> We definitely need to understand the above.
> > 
> > there is a hardware-bug which may cause this...afair i saw this with
> > the card in r64 with earlier Kernel-versions where other cards work
> > (like the mt7612e).
> 
> I don't think a HW bug affecting PCI would cause what we are seeing
> here, unless it results in memory corruption.


[1] 
https://www.asiarf.com/shop/wifi-wlan/wifi_mini_pcie/ws2433-wifi-11ac-mini-pcie-module-manufacturer/
[2] grep -Rni 'msi' drivers/net/wireless/mediatek/mt76/mt76x2/
[3] https://patchwork.kernel.org/project/linux-mediatek/list/?series=372885