Is PPC 44x PIKA Warp board still relevant?

Is PPC 44x PIKA Warp board still relevant?

[Dmitry Torokhov]

Hi Michael, Nick,

I was wondering if PIKA Warp board still relevant. The reason for my
question is that I am interested in dropping legacy gpio APIs,
especially OF-specific ones, in favor of newer gpiod APIs, and
arch/powerpc/platforms/44x/warp.c is one of few users of it.

The code in question is supposed to turn off green led and flash red led
in case of overheating, and is doing so by directly accessing GPIOs
owned by led-gpio driver without requesting/allocating them. This is not
really supported with gpiod API, and is not a good practice in general.
Before I spend much time trying to implement a replacement without
access to the hardware, I wonder if this board is in use at all, and if
it is how important is the feature of flashing red led on critical
temperature shutdown?

Thanks.

-- 
Dmitry

Re: Is PPC 44x PIKA Warp board still relevant?

[Christophe Leroy]

Hi Dmitry

Le 25/09/2022 à 07:06, Dmitry Torokhov a écrit :
> Hi Michael, Nick,
> 
> I was wondering if PIKA Warp board still relevant. The reason for my
> question is that I am interested in dropping legacy gpio APIs,
> especially OF-specific ones, in favor of newer gpiod APIs, and
> arch/powerpc/platforms/44x/warp.c is one of few users of it.

As far as I can see, that board is still being sold, see

https://www.voipon.co.uk/pika-warp-asterisk-appliance-p-932.html


> 
> The code in question is supposed to turn off green led and flash red led
> in case of overheating, and is doing so by directly accessing GPIOs
> owned by led-gpio driver without requesting/allocating them. This is not
> really supported with gpiod API, and is not a good practice in general.

As far as I can see, it was ported to led-gpio by

ba703e1a7a0b powerpc/4xx: Have Warp take advantage of GPIO LEDs 
default-state = keep
805e324b7fbd powerpc: Update Warp to use leds-gpio driver

> Before I spend much time trying to implement a replacement without
> access to the hardware, I wonder if this board is in use at all, and if
> it is how important is the feature of flashing red led on critical
> temperature shutdown?
> 

Don't know who can tell it ?

Maybe let's perform a more standard implementation is see if anybody 
screams ?

Christophe

Re: Is PPC 44x PIKA Warp board still relevant?

[Michael Ellerman]

Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> Hi Dmitry
>
> Le 25/09/2022 à 07:06, Dmitry Torokhov a écrit :
>> Hi Michael, Nick,
>> 
>> I was wondering if PIKA Warp board still relevant. The reason for my
>> question is that I am interested in dropping legacy gpio APIs,
>> especially OF-specific ones, in favor of newer gpiod APIs, and
>> arch/powerpc/platforms/44x/warp.c is one of few users of it.
>
> As far as I can see, that board is still being sold, see
>
> https://www.voipon.co.uk/pika-warp-asterisk-appliance-p-932.html

On the other hand it looks like PIKA technologies went bankrupt earlier
this year.

>> The code in question is supposed to turn off green led and flash red led
>> in case of overheating, and is doing so by directly accessing GPIOs
>> owned by led-gpio driver without requesting/allocating them. This is not
>> really supported with gpiod API, and is not a good practice in general.
>
> As far as I can see, it was ported to led-gpio by
>
> ba703e1a7a0b powerpc/4xx: Have Warp take advantage of GPIO LEDs 
> default-state = keep
> 805e324b7fbd powerpc: Update Warp to use leds-gpio driver
>
>> Before I spend much time trying to implement a replacement without
>> access to the hardware, I wonder if this board is in use at all, and if
>> it is how important is the feature of flashing red led on critical
>> temperature shutdown?
>
> Don't know who can tell it ?

I would be surprised if anyone is still running upstream kernels on it.

I can't find any sign of any activity on the mailing list related to it
since it was initially merged.

> Maybe let's perform a more standard implementation is see if anybody 
> screams ?

How much work is it to convert it?

Flashing a LED when the machine dies is nice, but not exactly critical,
hopefully the machine *isn't* dying that often :)

cheers

Re: Is PPC 44x PIKA Warp board still relevant?

[Dmitry Torokhov]

On Mon, Sep 26, 2022 at 08:41:53PM +1000, Michael Ellerman wrote:
> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> > Hi Dmitry
> >
> > Le 25/09/2022 à 07:06, Dmitry Torokhov a écrit :
> >> Hi Michael, Nick,
> >> 
> >> I was wondering if PIKA Warp board still relevant. The reason for my
> >> question is that I am interested in dropping legacy gpio APIs,
> >> especially OF-specific ones, in favor of newer gpiod APIs, and
> >> arch/powerpc/platforms/44x/warp.c is one of few users of it.
> >
> > As far as I can see, that board is still being sold, see
> >
> > https://www.voipon.co.uk/pika-warp-asterisk-appliance-p-932.html
> 
> On the other hand it looks like PIKA technologies went bankrupt earlier
> this year.
> 
> >> The code in question is supposed to turn off green led and flash red led
> >> in case of overheating, and is doing so by directly accessing GPIOs
> >> owned by led-gpio driver without requesting/allocating them. This is not
> >> really supported with gpiod API, and is not a good practice in general.
> >
> > As far as I can see, it was ported to led-gpio by
> >
> > ba703e1a7a0b powerpc/4xx: Have Warp take advantage of GPIO LEDs 
> > default-state = keep
> > 805e324b7fbd powerpc: Update Warp to use leds-gpio driver
> >
> >> Before I spend much time trying to implement a replacement without
> >> access to the hardware, I wonder if this board is in use at all, and if
> >> it is how important is the feature of flashing red led on critical
> >> temperature shutdown?
> >
> > Don't know who can tell it ?
> 
> I would be surprised if anyone is still running upstream kernels on it.
> 
> I can't find any sign of any activity on the mailing list related to it
> since it was initially merged.
> 
> > Maybe let's perform a more standard implementation is see if anybody 
> > screams ?
> 
> How much work is it to convert it?
> 
> Flashing a LED when the machine dies is nice, but not exactly critical,
> hopefully the machine *isn't* dying that often :)

OK, I think I figured out how to let platform code access the GPIOs
while still using leds-gpio driver for normal operation. I will send a
patch shortly.

Thanks.

-- 
Dmitry