p-paul
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Any plans to use the C0 stepping for the Pi4B?

Mon Jun 21, 2021 8:55 am

Dear Community,

does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?

Thanks a lot.

fruitoftheloom
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Re: Any plans to use the C0 stepping for the Pi4B?

Mon Jun 21, 2021 9:13 am

p-paul wrote:
Mon Jun 21, 2021 8:55 am
Dear Community,

does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?

Thanks a lot.

Raspberry Pi Trading do not have a publicly available roadmap of future products and changes to existing hardware..

Historically they have not publicised changes to existing SoCs...

...so it is a *guessing game* or *wishful overthinking* :shock:
Take what I advise as advice not the utopian holy grail, and it is gratis !!

6by9
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Re: Any plans to use the C0 stepping for the Pi4B?

Mon Jun 21, 2021 11:34 am

p-paul wrote:
Mon Jun 21, 2021 8:55 am
does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?
I believe all 8GB Pi4's already are.
Software Engineer at Raspberry Pi Ltd. Views expressed are still personal views.
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W. H. Heydt
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Re: Any plans to use the C0 stepping for the Pi4B?

Mon Jun 21, 2021 9:18 pm

6by9 wrote:
Mon Jun 21, 2021 11:34 am
p-paul wrote:
Mon Jun 21, 2021 8:55 am
does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?
I believe all 8GB Pi4's already are.
I wouldn't be surprised if other models were as well. I can't think of any particular reason to continue ordering two different steppings when one--the most recent one--would work for all the boards using the underlying design.

For something like the Pi400 vs. Pi4B/CM4 (or the Pi2Bv1.2 vs. Pi3B/B+), one could seen binning differences, but not stepping differences.

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HawaiianPi
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 1:13 am

p-paul wrote:
Mon Jun 21, 2021 8:55 am
does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?
As someone else already said, it makes sense that all Pi4 model will eventually have the newer SoC. As they run out of the older SoC stepping the newer one will be used in manufacturing other models. There will be no announcement. There will be no way to order a specific stepping. You will get what the reseller has in stock when you order it (just like the current three revisions of the Pi 4B).

They've done this before. There are Pi 3B models with the 3B+ flip-chip SoC (and probably Pi 2B v1.2 models as well).

EDIT: The real question is, why do you care? And what difference will it make?
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ejolson
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 3:38 am

HawaiianPi wrote:
Tue Jun 22, 2021 1:13 am
p-paul wrote:
Mon Jun 21, 2021 8:55 am
does anyone know if there are plans to use the C0 stepping of the BCM2711 also for the Pi4B at some point in the future?
EDIT: The real question is, why do you care? And what difference will it make?
Why the person making the original post cares and what difference it makes are not the questions. It would, however, be nice to have a concise summary of what changed with the C0 stepping.

jamesh
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 9:11 am

The most important change is the power gating improvements, but there are some minor bug fixes as well. These won't be noticeable as we worked round silicon issues in software prior to C0. C0 has less need of bounce buffer for SD card IO (no need up to 4GB) so there might be a tiny improvement there, all handled transparently by device tree.

As for which devices have which, all Pi400 and CM4 have C0. Pi4 will get C0 as and when the supply channel is flushed out - we have no visibility of when - there clearly will be times when B0 and C0 are in use. Basically because they are interchangeable parts, the production line could have either.

So really, the improvements for C0 are pretty small - there is no way of ordering a Pi4 with C0, and no real need anyway.
Principal Software Engineer at Raspberry Pi Ltd.
Working in the Applications Team.

6by9
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 9:42 am

I find it slightly odd that people ask for detailed differences with between hardware steppings as generally they are insignificant to the end user.

Intel publish info on which steppings you can buy (eg the i5-9400F is on U0!!! :o), but they don't appear to publish publicly details of those steppings.
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bensimmo
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 10:14 am

I think it's just curiosity and interest in your products and how you do things.
Some people like software, some like hardware, some like both.
Of course most just get on and use it :-)


With intel they have a long list of errata against steppings and a much wider base of product from one stepping as they improve to produce a higher end product or a more efficient power product.
You only have two 'model of chip'* the Pi4/CM4 and the Pi400 at it's higher clock. (open to the air and heatsinked standards as I see it)

*Intel has... who knows you can easily get lost in their numbering and lettering and which use what binned processor. I know they are not models in the Pi world , but the default clock speed would be a model number difference in the CPU world.

Anyways, interest and curiosity. Hardware education ?

So them sucked eggs...

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davidcoton
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 10:36 am

bensimmo wrote:
Tue Jun 22, 2021 10:14 am
I think it's just curiosity and interest in your products and how you do things.
+1. In an infinite curiosity loop. Or possibly a recursive function call.
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W. H. Heydt
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Re: Any plans to use the C0 stepping for the Pi4B?

Tue Jun 22, 2021 5:48 pm

6by9 wrote:
Tue Jun 22, 2021 9:42 am
I find it slightly odd that people ask for detailed differences with between hardware steppings as generally they are insignificant to the end user.
While generally true, not so in all cases. The shift in the BCM2837 to the inverted version with the change in packaging to include a metal heat spreader was significant. (And, FYI, I'm still hoping to see that show up on the Pi2Bv1.2. The last two of them I got--a couple of months ago--still have the older variant of the SoC, though that may be down to slow sales and longer inventory pass through.)

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