Raspberry Pi 3 - 64 Bit Operation

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Website · Post by **Zucca** » Wed Sep 21, 2016 11:36 am

Thanks Neddy.

I'll try to find matching one close by here. :)

NeddySeagoon wrote:Beware ebay, there are a lot of fakes around.

Yeah. That's true. I don't usually order items priced higher than $5. That way I won't lose too much money. ;) So far all the electric components I've ordered have been as they should. But this is more than just one component so I try to order it from somewhere else.
I have a slightly-better-than-average multimeter that I can use to test the adapter also.

Post by **NeddySeagoon** » Wed Sep 28, 2016 7:49 am

Team,

Just because I can, I'm moving my aarch64-unknown-linux-gnu Pi 3 to gcc-6.2.0-r1 and the gold linker.
So far, its

Code: Select all

completed emerge (272 of 832)

from emerge -e @world.

It will be a few days yet before I get to do any testing besides the tool chain, as libreoffice takes over a day to build.

On MAKEOPTS="-j4" it choked on boost. --resume with -j2

Website · Post by **Zucca** » Sat Oct 01, 2016 11:16 pm

NeddySeagoon wrote:Just because I can, I'm moving my aarch64-unknown-linux-gnu Pi 3 to gcc-6.2.0-r1 and the gold linker.

Nice.
Have things played out nicely?
Have you got any new features meanwhile? Sound? WiFi?

NeddySeagoon wrote:On MAKEOPTS="-j4" it choked on boost. --resume with -j2

I guess you already have '-pipe' disabled? ;)

Post by **NeddySeagoon** » Sun Oct 02, 2016 10:20 am

Zucca,

It all worked except
llvm - which repeatably locks the Pi up hard.
iproute2 - triggers an internal linker error
libreoffice - I was doing some electrics in the garage and took out all the power after about 8 hours, so its untested.
It was the last package.

I turned off -pipe a long time ago but I'm thinking about turning it on again.
If there is insufficient RAM, intermediate files will still be passed on disk.

I'm using the linux-next kernel with the .dtb from the bcm2837 because the .dts in linux-next has (at least) some clocks missing/incorrect.
The linux-next dts does not provide working USB, so you only get a serial console - I've not tested that.
The linux-next kernel with the bcm2837 .dtb gets you working USB and ethernet but no mmc.
I can live with that as everything except /boot is on a USB HDD.

Sound over HDMI needs the vc4 to work in 64 bit mode. That will be hard. The internet suggests it may need changes to the raspberrypi firmware.
Stereo analogue sound, mmc and wifi should all work once the dts is fixed in linux-next. Maybe bluetooth too. All the bits are out there, they just need
to be brought together.

Website · Post by **Zucca** » Sun Oct 02, 2016 7:07 pm

Hi Neddy.

NeddySeagoon wrote: The linux-next kernel with the bcm2837 .dtb gets you working USB and ethernet but no mmc.
I can live with that as everything except /boot is on a USB HDD.

Hm. I'm using your tarballs and I set my / on mmc, but I can still access USB storage. I'm getting something wrong here?

NeddySeagoon wrote: Sound over HDMI needs the vc4 to work in 64 bit mode. That will be hard. The internet suggests it may need changes to the raspberrypi firmware.
Stereo analogue sound, mmc and wifi should all work once the dts is fixed in linux-next. Maybe bluetooth too. All the bits are out there, they just need
to be brought together.

And I believe that even the offical Rasbian is 32-bit for RPi3? I wonder what's the point in bringing a mini computer that has 64-bit CPu into market if the manufacturer itself doesn't have ways to provide 64-bit OS there... Or is the Win10 IoT 64 bit? Oh well... RPi3 is mainly 32-bit anyways. It's just the CPU I've heard.

Post by **NeddySeagoon** » Sun Oct 02, 2016 8:34 pm

Zucca,

My tarballs are based on the bcm2837 kernel. There is no WiFi there but for different reasons.
I've taken to following the upstream kernel as there is lots going on on both arm64 and Raspberry Pi fronts.

The upstream kernel appears to have all the kernel modules needed for wifi and mmc, so I'm
trying to add in other device tree bits and pieces.
I'm learning how much I don't know about device trees in the process.

Real life has been getting in the way this last month or so, so it was easy to let the Pi build
gcc-6.2 and rebuild world as it didn't need much of my time.
I've been trying to add ~arm64 keywords to the tree but that's stalled meanwhile too.

The Pi 3 has the same I/O as all the other Pis. Everything is on a single USB2 port except
the mmc card. In the Pi3, the wifi is on mmc1 and the bluetooth on a serial port.
The 64 bit CPU was intended (by the Raspberry Pi Foundation) to be a go faster arm7a.

Not using it in 64 bit mode sees like a waste. Rather like a 32 bit install on a 64 bit PC.

It looks like various people have had all the bits working except the vc4, but not all at the same time.

Website · Post by **Zucca** » Sun Oct 02, 2016 10:00 pm

NeddySeagoon wrote:Not using it in 64 bit mode sees like a waste. Rather like a 32 bit install on a 64 bit PC.

Exactly the point why I want 64-bit OS too.

Hm. You said previously:

[post=7969512]NeddySeagoon[/post] wrote:There are two drivers in the kernel for SD Cards.
mmc and sdhost.

... so changing to another driver enables some but disables some also?

Post by **NeddySeagoon** » Mon Oct 03, 2016 7:10 am

Zucca,

My understanding at present is that mmc is used for the sdcard and sdhost is used for the wifi.

Website · Post by **Zucca** » Fri Oct 07, 2016 12:39 pm

Neddy, I'm asking if you just happen to have any experience on this...
I'm thinking of buying the offical 7" touch screen for my RPi3. Do you think it would work out-of-the-box with the Gentoo system I got from your site? Maybe just only running xrandr when X starts?
At first I don't need the touch functionality at all.

Post by **NeddySeagoon** » Fri Oct 07, 2016 4:29 pm

Zucca,

Probably not. I've almost certainly dropped the kernel drivers. Also, it will need a device tree overlay to set everything up.
There is probably a 32 bit device tree overlay in /boot/overlays. However, that may not work with the dtb in use in boot.

Looks like a fun project though.

Website · Post by **Zucca** » Fri Oct 07, 2016 4:38 pm

NeddySeagoon wrote:Looks like a fun project though.

Well. I have a dream to have some kind of touch screen tablet-like Raspberry Pi computer... At the final step I'd stuff all the empty space full of batteries. Maybe 18650s...
And no, it won't be slim or lightweight. One use for it could be and oscilloscope. But I'll take one step at the time and add features as I can tackle problems out of my way.

Website · Post by **Zucca** » Fri Oct 07, 2016 5:32 pm

I find this driver loading and device tree thing very confusing. I've always just relied on /etc/modprobe.d, kernel configuring and others to manage drivers...
I'll start digging around now. This looks promising: https://www.raspberrypi.org/documentati ... ce-tree.md

Post by **NeddySeagoon** » Fri Oct 07, 2016 10:46 pm

Zucca,

Its a start. /usr/src/linux/Documentation/devicetree/ is good too.

The devicetree describes the hardware to the kernel, so that DMA, IRQs memory mapped I/O and so on does not need to be hard coded.
If you remember the good old days of the ISA bus and cards with jumpers, its like putting all the jumper settings into a single file.
It means that the same kernel code will work for different embedded systems that have the same hardware but connected differently.
Its more than that but that likens it to something in the PC world.

There is a twist. Lots of things are optional and may be mutually exclusive, because they use the same resources in different ways.
This is where device tree overlays come to the rescue. Each overlay describes a single device.

On the Pi, they are loaded by naming them in config.txt.
Before the kernel starts the boot loader code assembles the entire device tree so that the kernel can find it when it starts.

Website · Post by **Zucca** » Sat Oct 08, 2016 10:26 am

NeddySeagoon wrote:Zucca,

Its a start. /usr/src/linux/Documentation/devicetree/ is good too.

Thanks. I'll see that too.

NeddySeagoon wrote:The devicetree describes the hardware to the kernel, so that DMA, IRQs memory mapped I/O and so on does not need to be hard coded.
If you remember the good old days of the ISA bus and cards with jumpers, its like putting all the jumper settings into a single file.
It means that the same kernel code will work for different embedded systems that have the same hardware but connected differently.
Its more than that but that likens it to something in the PC world.

That explained a lot. I do remember ISA and the IRQ number-hell in some cases. :)

Let the rtfm begin!

antonlacon · Post by **antonlacon** » Tue Nov 15, 2016 11:20 am

NeddySeagoon wrote: I turned off -pipe a long time ago but I'm thinking about turning it on again.
If there is insufficient RAM, intermediate files will still be passed on disk.

Have you made use of zram at all?

Post by **NeddySeagoon** » Tue Nov 15, 2016 11:47 am

antonlacon,

Hmm, I thought I had ... but # CONFIG_ZRAM is not set :(

Post by **NeddySeagoon** » Thu Dec 01, 2016 9:45 pm

Raspberry Pi 3 64 bit Updated earlier today.

Now with gcc-6.2.0-r1, ld.gold and firefox (with USE=bindist)
Still no WiFi, Bluetooth, nor anything that needs the GPU. That's all sound and hardware accelerated video.

If you prefer the pieces, the BINHOST is also available.

Post by **NeddySeagoon** » Mon Dec 26, 2016 12:19 pm

Raspberry Pi 3 64 bit Raspberry Pi 3 64 bit.
Now with wifi and bluetooth and faster microSD card support.

Also included, firefox with USE=bindist, and icedtea java, built using Oracles java VM.
Its quite usable headless.

The BINHOST has changed very little and has not yet been updated.
Most of the changes since the last update are to the kernel.

Post by **NeddySeagoon** » Wed Mar 29, 2017 6:50 pm

The First Anniversary Pi 64 bit Update is out.

As always, its two file systems to boot a Pi 3 in 64 bit mode.
The contents list tells what built and installed.
That does not mean that it works.

The BINHOST will be useful on any ARM Cortex-A53 install unless that install was built with gcc-4.x
in which case, the C++ packages will be incompatible due to the ABI change.