As much as I lament the outdated CPU cores in the i.MX 8M compared to the latest mobile SoC’s (Qualcomm Snapdragon, Samsung Exynos, Apple A-series, MediaTek Helios, Huawei Kirin, Xiaomi Surge, UNISOC), we have to acknowledge that none of those SoC’s will be manufactured 3 years from now, so we have a fundamental tradeoff between performance and longevity.
NXP has the longest production cycles of any modern SoC maker (although you can find longer support for microcontrollers like PIC and 8051). I doubt that the Intel Atom x7-E3950, nVidia Tegra Xavier, Rockchip RK3399, Allwinner A80 octa and Amlogic M802 will still be produced in 2028.
Like many aspects of the Librem 5, you have major tradeoffs, and I think that Purism could really improve its public image by explaining those tradeoffs so that people understand them. The comments that I read about the Librem 5 in /r/linux and Phoronix forums show that most people are clueless.
I think that there are several possible models for improvement while trying to avoid planned obsolescence:
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Fairphone’s model is to produce one model every 3.5 years and try to keep updating the software (which has proven very difficult and expensive because of Google’s strict Android compatibility tests). This has forced people to install LineageOS and do most upgrading on their own, but luckily Purism won’t have this problem with Linux.
Fairphone selects a higher end SoC which is slightly out-of-date at launch, but after 3 years, it is regarded as very antiquated, as are the rest of the parts. Then, Fairphone uses a modular design, so that new upgrades can be added. This worked with the 13MP camera mod for Fairphone 2, but Fairphone didn’t have the scale to be able to justify producing other mods like NFC, wireless charging, USB-C port, better speakers, larger battery, pico projector, Qwerty keyboard, etc.
Pinephone appears to be trying to follow the Fairphone model of allowing mods, but its SoC is so outdated, that mods can’t be used for upgrading components like the camera, so mods can only be used to offer other functionality, but not upgrades. For mods to work well, the phone has to be reasonably thin for adding to the back or allow internal parts to be exchanged, but neither happened with the Fairphone 2. -
SHIFT offers another model of launching new models every year, but trying to make the parts backward-compatible, so that older models are upgradeable and selling parts so that people who need up-to-date hardware can get it. This solves the problem of being out-of-date in the Fairphone model, because the platform remains up-to-date, but it also means that upgrades require replacing the entire motherboard, which is basically half the cost of buying new. It also means that SHIFT has to stock parts, which adds to the costs. You either have to buy in large batches and store parts or pay the elevated costs of small batches and finding more-expensive suppliers who will produce at small scale for you.
The other drawback is the requirement to be backward compatible, so that new models can’t adapt to some of the changes in the tech. SHIFT had to stay with the outdated 5" 9:16 screens in its SHIFT5.X series, although the industry has moved on to 6" 9:18-20 screens, which makes the old screens more expensive since they are now special orders. The only way around this problem was to create a whole new line, which SHIFT is now doing with the SHIFT6m. If SHIFT had followed convention in the mobile industry, it would have just launched a new model every year that changed in form factor and wasn’t backward-compatible, which would be much easier for a small company like SHIFT. -
The final option is the Apple model to keep releasing new updated models every year, but guarantee to keep providing software updates, so there is some improvement in functionality over time, but the extra processing and memory requirements of the new software often comes at the cost of lower performance. This can be mitigated to some degree by making heavier components optional and replaceable with lighter components in the operating system, and the modular nature of Linux makes this more possible that with other systems.
You can try to provide replacement parts for the older models, but this is more difficult than with the other two models, because you have much less demand per part. With a long-selling model like the Fairphone 2, you have enough volume to justify manufacturing replacement parts. With a backward-compatible model, you only need to stock the latest version of the part, since it will work in all models.
With this model, you get to keep your latest model hardware up-to-date, but it is hard to supply parts for older models as happens with Thinkpads, Latitudes and iPhones, because you don’t have millions of units being sold. The other drawback is that there is no possibility of upgrading the parts, so the whole unit needs to be junked in order to upgrade.
It seems to me that Purism has several options. I don’t know how realistic this is, but the two M.2 slots might provide some upgradeability or the ability to add mods. If the PCIe bus is disabled on the two M.2 slots (which I suspect it will be for security reasons), a lot can still be done with a USB 3.0 connection (but that also might be disabled for the M.2 B-key slot).
I would like to see Purism follow the SHIFT model, which should be easy since the i.MX 8M isn’t likely to have major architectural changes in the 14nm version. The fundamental question facing Purism is whether it wants to shift to a more powerful platform like the upcoming RK3588 or remain with the i.MX 8M and hope that NXP will both add Cortex-A7_X_ cores and keep shrinking the node size.
Now that we have decent Lima drivers for the Mali GPU, the RK3588 becomes a possibility (although we don’t know if if there will be other binary blobs that can’t be worked around). I’m very divided whether Purism should stay with the i.MX 8M or shift to the RK3588 in the future. If people today think that the Fairphone 2 with a Snapdragon 800 is antiquated, then the i.MX 8M Quad in the Librem 5 is going to seem even more ancient 4 years from now.