Re: [OpenOCD-user] Openocd SWD flash with sysfs or gpiod is too long on Radxa Pi / AMLogic S905Y2

[Maximin C. <max...@gm...>]

Hi,

>Sysfs is slow (and deprecated by the kernel guys), gpiod is way faster.

Surprisingly, the flash duration is the same (+/1 sec) for gpiod and sysfs
here !

>I think there is a gpiod cable in openocd now, but i have not tested it
yet.

My apologies if this is a stupid but what is a "cable" in this context ?
I use gpiod in my configuration file using the following adapter command:
"adapter driver linuxgpiod"

Best regards,

-- 
Maximin COSTE


Le jeu. 28 juil. 2022 à 16:06, Benjamin Henrion <zo...@gm...> a écrit :

> Le jeu. 28 juil. 2022 à 14:42, Maximin COSTE <max...@gm...> a
> écrit :
>
>> Hi everybody,
>>
>> I was previously using openocd on a RPI Zero 1/2 to flash an STM32F412
>> using SWD protocol.
>> The whole flashing operation takes around 5 to 6 seconds which is fine.
>> My only constraint is that operation takes no more than those 5 to 6
>> seconds (it is
>> because the STM32F4 sends keep-alive frames via CAN to the main battery.
>> If there is
>> no message received in the last ~7 sec, the battery shutdown and so does
>> the entiere
>> system).
>>
>> Due to the current shortage of RPI boards, I switched to Radxa Pi Zero
>> (https://wiki.radxa.com/Zero) with an AMLogic S905Y2 inside.
>> I have tried to use sysfs and gpiod (in my understanding, there are
>> pretty much the
>> same thing, and gpiod is newer ?) and despite thoses errors messages:
>>
>
> Sysfs is slow (and deprecated by the kernel guys), gpiod is way faster.
>
>
>> > Error: Translation from khz to adapter speed not implemented
>> (maybe it is because of the use of such "generic" layer)
>>
>> > Error executing event reset-start on target stm32f4x.cpu:
>> (here I am not sure what is going on...)
>>
>> it goes to the end, and flash is "correctly" done !
>>
>> My only (but big !) concern is that with sysfs or gpiod, the flashing
>> process takes around
>> 9-10sec and as specified in the beginning of this message, this is too
>> much, and
>> the system battery goes timeout with this duration...
>>
>> It is my understanding that the BCM2835gpio driver for OpenOCD uses
>> specific directs
>> RAM access to achieve the speed I mesured in my usage (5-6 seconds).
>> It looks like nothing comparable is available for AMLogic S905Y2/ Radxa
>> Pi ?
>> I might have no searched deep enough, or in the right place.
>> If nothing is available, how do you see this ? Should it be straight
>> forward to
>> implement ? Can I get at least the same performances I had with the
>> BCM2835gpio driver ?
>>
>
> I think there is a gpiod cable in openocd now, but i have not tested it
> yet.
>
> Best,
>
>
>
>> Best regards,
>>
>> --
>> Maximin COSTE
>> _______________________________________________
>> OpenOCD-user mailing list
>> Ope...@li...
>> https://lists.sourceforge.net/lists/listinfo/openocd-user
>>
>