6 ms·

I confess. I'm completely ignorant about the Raspberry Pi even though I have a 3rd generation I bought recently. So I don't really understand what the significa

by milesf 10y ago

I confess. I'm completely ignorant about the Raspberry Pi even though I have a 3rd generation I bought recently. So I don't really understand what the significance of "Blobless Linux" is. Is the Raspberry Pi an open-source software and hardware platform? If not, what is? What should I have bought if not the Pi3?

khedoros1 10y ago
> Is the Raspberry Pi an open-source software and hardware platform? No, the hardware isn't open, and not all of the software is, either. It requires a closed-source blob of code to boot the system. There's "real" firmware in the VC4 chip, which is the first part of the Pi to come up, some binary blob bootloader files, and drivers handling graphics and hardware decoding that are still closed. There is an open-source 3D driver, but it's missing some capabilities from the closed one (hardware accelerated video decoding), but includes some extras (some degree of support for non-mobile OpenGL). The chips from most other vendors are at least bootable without blobs, even if video output won't be properly accelerated.
- christina_b 10y ago
  >drivers handling graphics Actually that's open and mainlined now, there are DRM drivers for BCM285x family but they rely on mailbox interfaces for power and clock management.
- deleted 10y ago
  [deleted]
superflyguy 10y ago
There is no sane reason which would explain why you should not have bought a Pi. Open or not it would not make any difference to more than a small room full of people. A bunch of people spent years designing hardware and negotiating with people to get the Pi built at a low cost and it's become the best selling UK computer ever with over 10,000,000 sales. It's succeeded at what it was supposed to do; provide an educational platform for kids.
- paulmd 10y ago
  It's really doubtful that more than a tiny fraction of RPi sales have gone to kids. Be honest here, whatever the RPi Foundation's marketing, the overwhelming majority have gone to hobbyists. The RPi is uniquely unsuited to an educational environment anyway. The SD cards are unreliable, especially in combination with the RPi's poor power filtering and the cheapo phone adapters it's usually paired with. Anyone who has used a RPi has had to deal with filesystem corruption and SD card failures, intermittent USB bus brownouts, etc, and I can only imagine the nightmare of having to maintain a lab with 50 of the things. You can't PXE boot them (let alone remote-manage them) because they have no BIOS, just a blob on a physical card that needs to be swapped out. The Pi should have had eMMC day one, and shipped with a proper power adapter and better power filtering. But much like their choice of Broadcom SoCs - they made a political decision that they were going to market primarily around the $35 price point, and so they cheaped out on $5-10 worth of hardware and ended up with a device that was entirely unsuitable for their stated purpose. And the terrible thing is - the PC is not the sole component in the system anyway. The Pi still needs a case, a a monitor, keyboard, switches, etc, and if you are trying to stand up a lab for the first time it's not like you have 50 monitors or keyboards laying around for free, you need to buy those. So you are looking at more like $150 per system anyway, and the $10 you save on cheaping out on the hardware becomes a meaningless fraction of the total cost. Just buy the right hardware the first time. An ECS Liva is only like $75 anyway, it comes with a case, onboard eMMC, AC adapter, and wifi, you've made up the difference in cost in accessories included in the box. There were many other terrible design decisions as well - such as the choice of USB as a system bus, which is again entirely unsuitable, especially when you are running on a low-power processor where running the USB bus full-tilt eats a significant fraction of your CPU cycles. It's like that shitty Mac Performa x200 road-apple design with the split half-width left-hand/right-hand busses which couldn't talk to each other, it eats up all your cycles by just using your disk or network. Even if the processor on other boards is no faster in synthetic benchmarks - they have a proper system architecture with SATA and often USB 3.0 and gigabit ethernet that makes an enormous difference in real-world performance. http://lowendmac.com/2014/power-mac-and-performa-x200-road-apples/ http://lowendmac.com/2014/power-mac-and-performa-x200-road-a... Furthermore - the Pi was plagued by driver problems with its USB stack for years. It would randomly drop USB frames when operated at USB 2.0 speeds, and it took upwards of 2 years after launch for the Pi foundation to get around to pushing a fix (again, because they chose a processor for which they could not release documentation, and they did not employ enough staff to actually fix their issues). How on earth are you supposed to do education on it when they can't even get their system bus to be stable? https://www.raspberrypi.org/forums/viewtopic.php?t=5249 https://www.raspberrypi.org/forums/viewtopic.php?t=5249 https://github.com/raspberrypi/firmware/issues/19 https://github.com/raspberrypi/firmware/issues/19 https://github.com/raspberrypi/firmware/issues/9 https://github.com/raspberrypi/firmware/issues/9 You know what I would do if I was running an actual lab? ECS Liva Xs, or other cheapo x86 PCs running a standard stack. Or go down to your university surplus store and pick up as many generic Dell boxes as you need for $50 apiece, out the door, ready to work. The Pi is good for embedded hobbyist work (the i2c interface is very powerful), but it totally fails as a machine for teaching programming compared to Ye Olde White Box. I tried to run a pair of RPis as my fileservers for about a year and a half, and I finally just gave up and sold them. They aren't good for the "mini Linux PC" application at all, compared to properly-designed hardware that you can buy for only a little bit more money (or sometimes even less money, especially when you work out the total system cost). (note: Pi3s can finally PXE boot without a SD card, which is like the bare minimum requirement for running an educational PC lab without going insane)
wycx 10y ago
If your use case is for a low power server, something that many people seem to do, then a Raspberry Pi is suboptimal. Something based on the Allwinner A20 makes a good choice as the SoC has an integrated ethernet (10/100) and SATA controllers, which means no USB-to-ethernet or USB-to-SATA half-arsery. I am running an old A10-based Mele A2000 with wired ethernet and a 1 TB SATA HDD as a home server. Stock Debian with a mainline kernel and mainline u-boot 'just works' if you want to run a headless server. If you want some GPIOs and other pins broken out, look at boards from Olimex [1] or Itead [2] or Cubie [3]. [1] https://www.olimex.com/Products/OLinuXino/A20/open-source-hardware https://www.olimex.com/Products/OLinuXino/A20/open-source-ha... [2] https://www.itead.cc/development-platform/arm.html https://www.itead.cc/development-platform/arm.html [3] http://cubieboard.org/model/ http://cubieboard.org/model/

by milesf 10y ago

khedoros1 10y ago

> Is the Raspberry Pi an open-source software and hardware platform? No, the hardware isn't open, and not all of the software is, either. It requires a closed-source blob of code to boot the system. There's "real" firmware in the VC4 chip, which is the first part of the Pi to come up, some binary blob bootloader files, and drivers handling graphics and hardware decoding that are still closed. There is an open-source 3D driver, but it's missing some capabilities from the closed one (hardware accelerated video decoding), but includes some extras (some degree of support for non-mobile OpenGL). The chips from most other vendors are at least bootable without blobs, even if video output won't be properly accelerated.

christina_b 10y ago
>drivers handling graphics Actually that's open and mainlined now, there are DRM drivers for BCM285x family but they rely on mailbox interfaces for power and clock management.
deleted 10y ago
[deleted]

superflyguy 10y ago

There is no sane reason which would explain why you should not have bought a Pi. Open or not it would not make any difference to more than a small room full of people. A bunch of people spent years designing hardware and negotiating with people to get the Pi built at a low cost and it's become the best selling UK computer ever with over 10,000,000 sales. It's succeeded at what it was supposed to do; provide an educational platform for kids.

paulmd 10y ago
It's really doubtful that more than a tiny fraction of RPi sales have gone to kids. Be honest here, whatever the RPi Foundation's marketing, the overwhelming majority have gone to hobbyists. The RPi is uniquely unsuited to an educational environment anyway. The SD cards are unreliable, especially in combination with the RPi's poor power filtering and the cheapo phone adapters it's usually paired with. Anyone who has used a RPi has had to deal with filesystem corruption and SD card failures, intermittent USB bus brownouts, etc, and I can only imagine the nightmare of having to maintain a lab with 50 of the things. You can't PXE boot them (let alone remote-manage them) because they have no BIOS, just a blob on a physical card that needs to be swapped out. The Pi should have had eMMC day one, and shipped with a proper power adapter and better power filtering. But much like their choice of Broadcom SoCs - they made a political decision that they were going to market primarily around the $35 price point, and so they cheaped out on $5-10 worth of hardware and ended up with a device that was entirely unsuitable for their stated purpose. And the terrible thing is - the PC is not the sole component in the system anyway. The Pi still needs a case, a a monitor, keyboard, switches, etc, and if you are trying to stand up a lab for the first time it's not like you have 50 monitors or keyboards laying around for free, you need to buy those. So you are looking at more like $150 per system anyway, and the $10 you save on cheaping out on the hardware becomes a meaningless fraction of the total cost. Just buy the right hardware the first time. An ECS Liva is only like $75 anyway, it comes with a case, onboard eMMC, AC adapter, and wifi, you've made up the difference in cost in accessories included in the box. There were many other terrible design decisions as well - such as the choice of USB as a system bus, which is again entirely unsuitable, especially when you are running on a low-power processor where running the USB bus full-tilt eats a significant fraction of your CPU cycles. It's like that shitty Mac Performa x200 road-apple design with the split half-width left-hand/right-hand busses which couldn't talk to each other, it eats up all your cycles by just using your disk or network. Even if the processor on other boards is no faster in synthetic benchmarks - they have a proper system architecture with SATA and often USB 3.0 and gigabit ethernet that makes an enormous difference in real-world performance. http://lowendmac.com/2014/power-mac-and-performa-x200-road-apples/ http://lowendmac.com/2014/power-mac-and-performa-x200-road-a... Furthermore - the Pi was plagued by driver problems with its USB stack for years. It would randomly drop USB frames when operated at USB 2.0 speeds, and it took upwards of 2 years after launch for the Pi foundation to get around to pushing a fix (again, because they chose a processor for which they could not release documentation, and they did not employ enough staff to actually fix their issues). How on earth are you supposed to do education on it when they can't even get their system bus to be stable? https://www.raspberrypi.org/forums/viewtopic.php?t=5249 https://www.raspberrypi.org/forums/viewtopic.php?t=5249 https://github.com/raspberrypi/firmware/issues/19 https://github.com/raspberrypi/firmware/issues/19 https://github.com/raspberrypi/firmware/issues/9 https://github.com/raspberrypi/firmware/issues/9 You know what I would do if I was running an actual lab? ECS Liva Xs, or other cheapo x86 PCs running a standard stack. Or go down to your university surplus store and pick up as many generic Dell boxes as you need for $50 apiece, out the door, ready to work. The Pi is good for embedded hobbyist work (the i2c interface is very powerful), but it totally fails as a machine for teaching programming compared to Ye Olde White Box. I tried to run a pair of RPis as my fileservers for about a year and a half, and I finally just gave up and sold them. They aren't good for the "mini Linux PC" application at all, compared to properly-designed hardware that you can buy for only a little bit more money (or sometimes even less money, especially when you work out the total system cost). (note: Pi3s can finally PXE boot without a SD card, which is like the bare minimum requirement for running an educational PC lab without going insane)

wycx 10y ago

If your use case is for a low power server, something that many people seem to do, then a Raspberry Pi is suboptimal. Something based on the Allwinner A20 makes a good choice as the SoC has an integrated ethernet (10/100) and SATA controllers, which means no USB-to-ethernet or USB-to-SATA half-arsery. I am running an old A10-based Mele A2000 with wired ethernet and a 1 TB SATA HDD as a home server. Stock Debian with a mainline kernel and mainline u-boot 'just works' if you want to run a headless server. If you want some GPIOs and other pins broken out, look at boards from Olimex [1] or Itead [2] or Cubie [3]. [1] https://www.olimex.com/Products/OLinuXino/A20/open-source-hardware https://www.olimex.com/Products/OLinuXino/A20/open-source-ha... [2] https://www.itead.cc/development-platform/arm.html https://www.itead.cc/development-platform/arm.html [3] http://cubieboard.org/model/ http://cubieboard.org/model/