OESF Portables Forum
Model Specific Forums => Gemini PDA => Gemini PDA - Linux => Topic started by: speculatrix on October 20, 2017, 09:57:12 am
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https://player.vimeo.com/video/239095559?portrait=0 (https://player.vimeo.com/video/239095559?portrait=0)
looks like we finally got a new Zaurus!
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Talk about fast posting, the video was uploaded just 2 hours ago
Here's a link to the Vimeo page, showing the comments too:
https://vimeo.com/239095559 (https://vimeo.com/239095559)
Yes, it looks like it might be a worthy successor, let's cross our fingers about the overall build quality...
I wonder how does the switch on button work, how do you select either OS if the unit is switched off? Also, I wonder if something like grub or kexecboot will be installable.
Varti
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Some interesting insights on Linux on the Gemini, on the maemo.org forum:
https://talk.maemo.org/showthread.php?t=99022&page=9 (https://talk.maemo.org/showthread.php?t=99022&page=9)
They are using LittleKernel as a bootloader, and it seems that it will be possible to use Linux from Android via chroot, in order to avoid to have to reboot:
https://talk.maemo.org/showpost.php?p=15344...mp;postcount=83 (https://talk.maemo.org/showpost.php?p=1534427&postcount=83)
https://github.com/littlekernel/lk/wiki/Introduction (https://github.com/littlekernel/lk/wiki/Introduction)
Mediatek releases drivers for Android only, so for Linux they'll have to either rewrite the drivers, or use libhybris to use Android's ones. The Linux distro shown in the video probably uses libhybris.
https://talk.maemo.org/showpost.php?p=15371...mp;postcount=88 (https://talk.maemo.org/showpost.php?p=1537188&postcount=88)
https://talk.maemo.org/showpost.php?p=15373...mp;postcount=92 (https://talk.maemo.org/showpost.php?p=1537371&postcount=92)
https://en.wikipedia.org/wiki/Hybris_(software) (https://en.wikipedia.org/wiki/Hybris_(software))
Varti
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Out of curiosity I did email Planet Computers Ltd to ask about a few points in regards to Linux and also Android support. Please take my predictions below with a grain of salt as they are just guesses at this stage.
- What bootloader software is used and how to change between Android and Linux? [unknown, Little Kernel mentioned, but possibly native Android with the ability to load a "secondary linux kernel" that needs to have a nested environment on a SD card or chroot]
- Is Linux and Android sharing the same SSD or can a "proper Linux" only boot from SD ? (as it is with many native Android devices) [possibly SD only for dual boot or SDD only for Linux if Android is wiped, see above.]
- Does the Gemini PDA support 4G and GPS under Linux or only under Android ? (What chip-sets are used, are drivers open-source?, MediaTech Android Only) [Unlikely, that 4G and GPS will be open-source under Linux, not good]
- Is the display "portrait native" and therefore needs rotation or does it support the advertised 2160 x 1080 natively in landscape ? (Linux would need possibly software rotation as the GPU driver is Android only) [Likely scenario]
- Does the display take up the full space on the screen or is it limited to 16:9 as shown on the prototypes ? [possibly only 1080 x 1920 in portrait + rotation]
I would appreciate if anyone has some more specific details about the questions raised to help to clarify these. I will post an update once I get some feedback from Planet Computers.
The downside here is that as with many other "Android only" devices that the kernel is often outdated and no further progress can be made unless the vendor (MediaTek in this case) does release a source or update of their SDK.
Quite frustrating that the focus is so much on Android. I wish they would not advertise Linux support at all.
Some interesting insights on Linux on the Gemini, on the maemo.org forum:
https://talk.maemo.org/showthread.php?t=99022&page=9 (https://talk.maemo.org/showthread.php?t=99022&page=9)
They are using LittleKernel as a bootloader, and it seems that it will be possible to use Linux from Android via chroot, in order to avoid to have to reboot:
https://talk.maemo.org/showpost.php?p=15344...mp;postcount=83 (https://talk.maemo.org/showpost.php?p=1534427&postcount=83)
https://github.com/littlekernel/lk/wiki/Introduction (https://github.com/littlekernel/lk/wiki/Introduction)
Mediatek releases drivers for Android only, so for Linux they'll have to either rewrite the drivers, or use libhybris to use Android's ones. The Linux distro shown in the video probably uses libhybris.
https://talk.maemo.org/showpost.php?p=15371...mp;postcount=88 (https://talk.maemo.org/showpost.php?p=1537188&postcount=88)
https://talk.maemo.org/showpost.php?p=15373...mp;postcount=92 (https://talk.maemo.org/showpost.php?p=1537371&postcount=92)
https://en.wikipedia.org/wiki/Hybris_(software) (https://en.wikipedia.org/wiki/Hybris_(software))
Varti
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My Android phone is rooted. I've always rooted my phone and/or unlocked the bootloader, even though I usually stick to the stock OS. I root for a number of reasons:
* mounting and chrooting into a full linux installation
* using VPNs (not needed since Android introduced VPN support)
* using Titanium Backup Root (ideal when you upgrade, you can backup and restore apps and all their configs and data)
* removing or disabling bloat
* using tools which can block apps with too many permissions (not so necessary with newest Android versions)
* using ADB over wifi
* use tcpdump to analyse traffic and see if any apps are misbehaving
The first point is the relevant one here. I partition my SD card so that the first partition is used by Android (FAT32), then there's a second EXT4 partition for linux, then a third which is a small swap partition. I installed a fairly minimal debian desktop into that second partition. I could use a disk image file and loopback mount it I guess, but performance might suffer because of the encryption. You can install Debian or Ubuntu Arm linux into a disk image on an x86 PC because debootstrap works just fine.
To use it, I fire up a regular terminal in Android, or get a shell over ADB/USB or ADB/Wifi, and can fsck and mount the SD card partition. I have a few scripts in /data/local/bin to do this, they also mount/bind the emulated and real sdcards into that linux environment. Then I chroot into it, and have a few scripts ready to set up the environment.
Mostly I use the command line, so I can rsync photos off the phone onto my file server, and rsync music onto the phone. I can start an ssh daemon so I can ssh into the phone, or push music from the file server using the rsync command.
If I really really want to use a graphical program, I can start vncserver with a virtual frame buffer, and then run the GUI program in linux on that, and then in Android use VNC Viewer to give me the linux experience; I can also VNC into that from a PC as well of course.
I'm not saying that this is what Planet will do, but if you have root on your phone, plus a busybox which has a large number of the standard command line tools built in, and a linux installation you can chroot into, it's a pretty powerful environment
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I'm really hoping its a true Linux install and not merely sitting on top of Android. Time will tell. I'd be happy enough if the bootloader is unlocked, root available and all the Android source too - provided Google services are ENTIRELY optional. If not then I want full Linux end-of.
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I'm really hoping its a true Linux install and not merely sitting on top of Android. Time will tell. I'd be happy enough if the bootloader is unlocked, root available and all the Android source too - provided Google services are ENTIRELY optional. If not then I want full Linux end-of.
Same here. Planet has apparently pushed Mediatek for Linux drives for his CPU, time will tell how much of this will become reality.
Varti
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Same here. Planet has apparently pushed Mediatek for Linux drives for his CPU, time will tell how much of this will become reality.
I've a friend who lives and works in Hong Kong and buys various electronics and SoCs, and says that Mediatek are too big and too uncaring to deal with unless you're really big and are spending enough for them to notice.
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I'm really hoping its a true Linux install and not merely sitting on top of Android. Time will tell. I'd be happy enough if the bootloader is unlocked, root available and all the Android source too - provided Google services are ENTIRELY optional. If not then I want full Linux end-of.
So I tweeted Planet asking if Single Boot linux only - removing Android was possible. Their answer a succinct "Yes".
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So I tweeted Planet asking if Single Boot linux only - removing Android was possible. Their answer a succinct "Yes".
Thanks for this info, other people have been wondering this too. I believe Android will be installed on the internal storage, I wonder if Linux will be stored there too. I'm planning to install both Android and Linux on the SD card, if possible and if there won't be much of a difference speed wise, to avoid wearing out the internal storage, especially with the swap partition.
Varti
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So I tweeted Planet asking if Single Boot linux only - removing Android was possible. Their answer a succinct "Yes".
Thanks for this info, other people have been wondering this too. I believe Android will be installed on the internal storage, I wonder if Linux will be stored there too. I'm planning to install both Android and Linux on the SD card, if possible and if there won't be much of a difference speed wise, to avoid wearing out the internal storage, especially with the swap partition.
Varti
I think it's been made clear that Linux will go in the internal storage, in that they say it will be dual boot (not merely that dual boot is possible) and there's never been any mention of them including an SD card, populated or unpopulated. That having been said, I don't see any reason why one couldn't put the swap partition on the SD card; indeed, that would make good sense.
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I think the android kernel has been tweaked to not require swap. But you'll definitely want to put it on your sd card, whether as a partition or swap file.
Android 7 on my LG v20 tells me my memory card is corrupt when it boots because there are three partitions, the first is fat32 (as usual), then 4GB as ext4 for Linux (chroot) then 1GB for swap.
However, I just cancel the warning and everything works fine.
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I think it's been made clear that Linux will go in the internal storage, in that they say it will be dual boot (not merely that dual boot is possible) and there's never been any mention of them including an SD card, populated or unpopulated. That having been said, I don't see any reason why one couldn't put the swap partition on the SD card; indeed, that would make good sense.
I disagree. In the demonstration of booting Linux, a restart with a button-hold during restart was required. That is a hardware pointer change. This tells me that it is most likely booting from the microSDXC at that point.
If both were booting from the same eMMC device, then there would need to be a software pointer change (to the bootloader) and would not require a held button during boot.
"Linux dual boot capable" is not the same thing as "We're shipping every unit with Android and Linux both pre-installed." I'm pretty sure booting Linux will be a, "bring your own," exercise.
You take your own microSDXC card, download a Debian ARM image - likely to be linked from this forum at some point - and use dd from a Linux terminal on another machine to copy the bootable Debian ARM image to your microSDXC which you then place in the Gemini's microSDXC slot. To boot to from microSDXC instead of eMMC, you will then have to hold the voice assist button on the side of the unit. At that point you have fulfilled your dual boot capability.
Now, as above, this does not preclude someone from wiping Android off of their device. However, to get to there is going to require that you root your Android device and re-point the bootloader to the Linux image that you'll load to the eMMC.
Neither does this preclude someone from re-partitioning the eMMC to include both Android and Linux partitions or putting the Linux install in a folder under Android and running it as a chroot. There are -lots- of options.
But, and I hope Planet clarifies this, I do NOT expect the shipping units to have Linux pre-installed on the eMMC. I also do not expect that they will have Linux 3D drivers for the Mali T880 graphics system. We'll likely be stuck at 2D acceleration only under Linux. For that we'll be at the mercy of Mediatek. Mediatek's history isn't exactly Linux friendly. Maybe this is the project where they redeem themselves.
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I also do not expect that they will have Linux 3D drivers for the Mali T880 graphics system. We'll likely be stuck at 2D acceleration only under Linux. For that we'll be at the mercy of Mediatek. Mediatek's history isn't exactly Linux friendly.
What about using libhybris to use the Android's 3d driver under a Wayland compositor? This would restrict the choice of a display server (basically, only Enlightenment and Gnome 3's Mutter), but it might be a viable solution.
Varti
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I also do not expect that they will have Linux 3D drivers for the Mali T880 graphics system. We'll likely be stuck at 2D acceleration only under Linux. For that we'll be at the mercy of Mediatek. Mediatek's history isn't exactly Linux friendly.
What about using libhybris to use the Android's 3d driver under a Wayland compositor? This would restrict the choice of a display server (basically, only Enlightenment and Gnome 3's Mutter), but it might be a viable solution.
Varti
Mmm... I would prefer to push this back to Planet Computers and them to push back to MediaTek. Supporting dual booting the SoC to Linux -should- include support for the 3D driver.
Doing this under a Wayland compositor - I'm not aware of any solutions using this where general people are using the resulting system for useful tasks. There are a few cases used as proof of concept examples - kind of, "Hold my beer and check this out!"
Do you know of working examples on a Mediatek X27 or even X25 SoC where the solution is stable enough to be used on a daily basis?
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A month ago I asked PC about the Linux situation and their reply said it was in the firmware. You have to wade back through quite a few comments to see it.
I've never done an attachment here but will try to add the screen print of their reply.
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A month ago I asked PC about the Linux situation and their reply said it was in the firmware. You have to wade back through quite a few comments to see it.
I've never done an attachment here but will try to add the screen print of their reply.
What planet said in your screen capture:
"Terry, we will provide direct boot into Linux on firmware versions. Regards, Planet"
Call me overly negative, but I suspect you are reading more into that than they actually said.
They did NOT say that Android and Linux were both going to be present in the firmware (eMMC) on shipped units.
They DID say that they, "will provide direct boot into Linux on firmware versions."
I interpret that as downloadable Linux that you can use to replace the Android install on the eMMC or, as in the example they showed at CES, use the image boot Linux from the microSDXC.
Really, it's actually a good thing if Linux isn't co-mingled with Android on the factory eMMC image.
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I disagree. In the demonstration of booting Linux, a restart with a button-hold during restart was required. That is a hardware pointer change. This tells me that it is most likely booting from the microSDXC at that point.
The good news is, we shall know which of us read the tea leaves correctly pretty soon now.
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What planet said in your screen capture:
"Terry, we will provide direct boot into Linux on firmware versions. Regards, Planet"
Call me overly negative, but I suspect you are reading more into that than they actually said.
They did NOT say that Android and Linux were both going to be present in the firmware (eMMC) on shipped units.
They DID say that they, "will provide direct boot into Linux on firmware versions."
All the demo versions had Linux installed. In other interviews they said they were shipping units that would dual boot Android with Linux. None of us will know exactly how that is accomplished until we (or someone) gets their devices.
My problem with having Linux on any type of sd card is the limited write capability. I know some are better than others but it just sounds problematic. I will be disappointed if that's the way they do it. (It's fine for a person to do that for themselves, of course. ) It would also make it more complicated to swap out the sd cards with your own data.
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The good news is, we shall know which of us read the tea leaves correctly pretty soon now.
Agreed. It's great that the project is advancing more or less on time. Do we have anyone in the audience who is in the top 500+/- units who can give us all a realistic review/report?
So far, the tech bloggers have been mostly worthless script readers & repeaters.
My problem with having Linux on any type of sd card is the limited write capability. I know some are better than others but it just sounds problematic. I will be disappointed if that's the way they do it. (It's fine for a person to do that for themselves, of course. ) It would also make it more complicated to swap out the sd cards with your own data.
Really, it isn't so bad booting Linux from SDXC media on a modern 104MB/s controller using a modern microSDXC card. If you want to see, download a live image and write it to a microSDXC card in a USB 3.0 reader and boot from it. Seconds not minutes.
Write isn't as big of an issue as people try to make it out to be. Consider your use case. You read from the card to boot. You read from the card to launch applications. You read from the card to open that file you're going to work on or the save game you're going to restore. You only write to it when you save - which is generally one much smaller file.
The microSDXC card in the Gemini is not hot swapable. I.e. you'll want to shut the device down before removing the back cover and changing the microSDXC card. Ideally most of us will put one big fast card in it and be set for the next 2+ years. There isn't really any need to remove the card unless you're going to change the partitioning or upgrade the card to a larger one.
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So, now we know. I was right and wrong.
Right - the Gemini is shipping without Linux pre-installed. It will be up to the end-user to download and install.
Wrong - it looks like there will be a partitioning tool to split up the onboard 64GB eMMC into multiple partitions so that Debian can co-locate on the device with Android.
Maybe Right - the above multi-partition solution implies that the re-partitioning system boots from microSDXC. Assuming they aren't reinventing the wheel, it is likely a tiny Linux bootable microSD card image with the partitioning software and Linux installer - maybe like a 'live' version. It should be possible, for those of us who would prefer it, to install Linux to the microSDXC card instead of the eMMC.
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Maybe Right - the above multi-partition solution implies that the re-partitioning system boots from microSDXC. Assuming they aren't reinventing the wheel, it is likely a tiny Linux bootable microSD card image with the partitioning software and Linux installer - maybe like a 'live' version. It should be possible, for those of us who would prefer it, to install Linux to the microSDXC card instead of the eMMC.
Where did you see the implication that it boots from the card? It looks as if it is part of the flashing software, which runs on a Windows or Linux machine or a Mac.
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as I'd prefer to have Debian preinstalled and maybe it won't be in Gemini, I wonder if there will be an easy tutorial to flash the disk with Gemini Flash tool and how to install Linux Debian in the Gemini without a glitch. Also how to use a SD to make a partition shared between Android and Linux.
Not every users that want to try Linux are so "geek" to operate without to fear "bricking" the PDA...
Thank you!
Salvo
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Maybe Right - the above multi-partition solution implies that the re-partitioning system boots from microSDXC. Assuming they aren't reinventing the wheel, it is likely a tiny Linux bootable microSD card image with the partitioning software and Linux installer - maybe like a 'live' version. It should be possible, for those of us who would prefer it, to install Linux to the microSDXC card instead of the eMMC.
Where did you see the implication that it boots from the card? It looks as if it is part of the flashing software, which runs on a Windows or Linux machine or a Mac.
In order to re-partition a disk/drive/eMMC/SSD, the device needs to be activated (booted) from an alternate boot point. With the Gemini this means one of seven methods.
1. Boot from the eMMC to a RAM disk then unmount the eMMC and make it available to the USB port as device to be overwritten by a PC/host computer. This is unreliable and a short path to brickage if the process gets interrupted.
2. Boot from an OS on the microSD then either load the OS directly to the eMMC from an image on the microSD. This is how many Android devices with microSD slots were able to load Cyanogenmod. Usually initiated by holding a button on the device during power on (to switch the boot target). This is exactly the process that Planet appeared to be doing to boot to Linux at CES, which is why I'm pretty sure they were booting Linux from microSDXC cards there.
3. Boot from USB media - process is essentially the same as #2 above. Needs some sort of switch (button hold at power on) to tell it to target USB for booting.
The two above can all be done with JUST the Gemini - no additional computer required. All simple with very low likelihood of bricking the device.
Boot the Gemini to Android (normal function).
Download the microSDXC or USB stick installer image.
Write the image to it's destination (microSDXC or USB - whichever one it can boot from).
Verify/check the bootable installer image.
Boot from the installer (hopefully a Debian Live like instance).
Manipulate partitions, select target, install from the boot device to the unmounted eMMC.
If all else fails, re-download the installer ISO image on a PC and dd it onto media (microSDXC or USB) then boot the Gemini from that.
Simple, reliable.
4. Run specialized software on a PC to provide a virtualboot-host over the USB port (much like a USB boot image from #2). Unit needs to be put into a state to accept this boot target (as in #2 and #3) and an OS image to write to the unmounted eMMC. This is how most consumer devices without microSD ports (phones, tablets, ereaders, etc) get their initial factory OS loaded. Usually there is some form of encrypted signing involved to validate the imaging connection. This is complicated and and an entirely unnecessary step as the device would need to be able to boot from a USB image to begin with - at which point it may as well boot from a live Linux image on a USB stick and work entirely within the Gemini itself. I.e. why on earth would they select this method requiring two computers - one of which they cannot predict the state of (your PC) - when it could be completely done within the one (Gemini) that they know you will have in-hand and a piece of media (microSDXC or USB stick) that is ubiquitous.
Regardless of the method above, there must be a method to change the boot-from device for the above methods to work.
5. Load a special - usually signed - 'installer file' to the device then reboot it. The existing OS on the device checks the directory during boot to see if there is a software update, and if so, boots into a special state where the contents of the file are exploded out to overwrite the other system files. This method is unlikely to be used for the purpose of adding/moving/shrinking/expanding/changing partitions though as it requires the partition to be active and mounted in order to read the file - unless it reads the file into a ram disk to then flip to while it overwrites the root/system files (again with brickability). This is probably how your cell phone gets it's OS updates. Special signed file is downloaded, phone reboots, installs new files from the special file over the old files.
6. BIOS/system/firmware boot order includes USB check to see if there is a USB host connected and waiting - then if so puts the device in a USB device mode entirely driven within firmware. At that point it makes an easy target to repartition from the computer it is connected to and any OS image is a dd from image file away. This method has some drawbacks too. It requires that the device have a distinct and independent USB logic controller to act as 'device mode' that runs before the eMMC boots. Effectively a sub-computer with it's own firmware within the Gemini just to handle running it in device mode USB. This strikes me as unlikely, difficult to secure, and very unreliable.
7. Magic. This is a placeholder in case they dreamed up something entirely novel or at least new to me.
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What leads me to suppose it will require a USB connection to a PC or a Mac is that they seem to say as much in Update 49:
"We have developed a Gemini Flashing Tool that will enable you to partition your Gemini flash memory and install Linux alongside Android. The Gemini Flashing Tool runs on a standard PC (in fact it should be able run on Windows, Mac and Linux) and it’s basically a front-end to well know utilities such as adb, Xflash and fastboot. It will guide you through the various steps needed to install Linux on the Gemini, allowing you to choose the space to be reserved for Android and for Linux.
"By using the partition tool you will basically transform your Android-only Gemini into a dual boot Android/Linux Gemini (and back, if you wish so). You can also use the tool to manually update Android, for example to install a rooted Android version."
They're silent on whether anything can be booted from a micro SD card.
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Just a minute ago Planet Computers updated the page support for Linux (http://support.planetcom.co.uk/index.php/Linux_Support):
«Please note that Linux support is still under development at the moment, and the Debian technology preview is mainly for people who wants to experiment with it. We will provide updated firmwares in the next few weeks, please stay tuned!»
Let's hope to have soon a Debian updated and an updated Gemini Flash Tool also.
Salvo
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New: Linux Flash Guide (http://support.planetcom.co.uk/index.php/Linux_Flash_Guide), welcome!
Salvo
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New: Linux Flash Guide (http://support.planetcom.co.uk/index.php/Linux_Flash_Guide), welcome!
Salvo
Thanks!
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Hi just got my Gemini and found this post, have downloaded the drivers and tool but the Debian img is corrupt, I've tried downloading a couple of times even used wget but every time I unzip it it says the img is corrupt. Anyone else having the same problem?
Ta, J
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Hi just got my Gemini and found this post, have downloaded the drivers and tool but the Debian img is corrupt, I've tried downloading a couple of times even used wget but every time I unzip it it says the img is corrupt. Anyone else having the same problem?
Ta, J
hi,
I haven't tried (not having still Gemini) but I'd advice to wait one or two weeks to install Linux: if I'm not wrong PC will release another update for Debian, as the "Technology preview" is still experimental and not yet complete.
Salvo
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Same here. Planet has apparently pushed Mediatek for Linux drives for his CPU, time will tell how much of this will become reality.
I've a friend who lives and works in Hong Kong and buys various electronics and SoCs, and says that Mediatek are too big and too uncaring to deal with unless you're really big and are spending enough for them to notice.
Unfortunately I am afraid that this is true. Mediatek only seem interested in launching 'updated' CPU's without providing much (if any!) support for earlier products, which is a shame.
Perhaps in hindsight it would have been better if Planet had used a processor from the 'Snapdragon' range, but of course hindsight is a wonderful thing!
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I have been using Debian for a few weeks now and like what is available. I was wondering if it is possible for KVM to be included with the next kernel?
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I have been using Debian for a few weeks now and like what is available. I was wondering if it is possible for KVM to be included with the next kernel?
The next kernel is likely to be 4.4 -- at least that's what the Android update would/will be, and we're tragically tied to the Android kernel. Whether it will be built in the default kernel, I do not know. But there are people burning their own kernels/modules/etc. from the source, which is available on, I believe, Davide's github site: https://github.com/dguidipc (https://github.com/dguidipc)
If I were to do this, I'd subscribe to the #gemini-pda freenode chat. People who have jumped through those hoops tend to be there.
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The next kernel is likely to be 4.4 -- at least that's what the Android update would/will be, and we're tragically tied to the Android kernel.
That's really good news, hopefully it will be 4.4 indeed, as it is an extended LTS release. My biggest worry with the Gemini was that we would be permanently stuck on 3.18, which is seriously outdated by this point and is likely to drop support if it hasn't already.
-RSS
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I have been using Debian for a few weeks now and like what is available. I was wondering if it is possible for KVM to be included with the next kernel?
The next kernel is likely to be 4.4 -- at least that's what the Android update would/will be, and we're tragically tied to the Android kernel. Whether it will be built in the default kernel, I do not know. But there are people burning their own kernels/modules/etc. from the source, which is available on, I believe, Davide's github site: https://github.com/dguidipc (https://github.com/dguidipc)
If I were to do this, I'd subscribe to the #gemini-pda freenode chat. People who have jumped through those hoops tend to be there.
Cool thanks.