7 ms·

STMicro MPU Supports Linux and Android

91 points by conductor 8y ago

mkesper 8y ago
I'd like to read the site but it doesn't allow it without accepting their tracking stuff. This is stupid.
monocasa 8y ago
I should hope so. The RPi2 is a quad core A7.
- kbumsik 8y ago
  You should know that the computation capabilities is not the only factor of the industrial embedded system and that chip does not even look at it. It much more focused on real-time capabilities and hardware control. Notable examples are 1. Built-in Cortex M4 microcontroller 2. RPi doesn't have ADCs but STM32MP1 got 16-bit ADCs and a sigma-delta modulator. 3. It's got 5V-tolerant GPIO whereas RPis are not 4. Best-in-class timers for PWM and quadrature encoders.
  - monocasa 8y ago
    The title has changed since I posted. It was something to the effect of "ST Micro Cortex-A7 supports Linux and Android". Which is sort of 'no shit, of course an A7 is easy to port Linux to.' Yes, I know that an RPi isn't the best microcontroller. My last job had me as the lead for a proprietary RTOS for a custom robotics system. In fact if you go into the STM32F docs for the SSI controller where it calls the busy flag "unreliable", that was my contribution.
dvfjsdhgfv 8y ago
See their official press release here: https://www.st.com/content/st_com/en/about/media-center/press-item.html/p4140.html https://www.st.com/content/st_com/en/about/media-center/pres...
magicalhippo 8y ago
ST is pushing hard it seems. They bought Atollic and made their TrueSTUDIO IDE free, and while it's Eclipse based it's pretty easy to set up and get going at least. They've got a plugin for it, STM32CubeMX, which helps you configure and generate initialization code* for the peripherals and clock. Having started out with Arduino I've lately been having fun with the STM32F103 "Blue Pill" boards. Like with this STM32MP1, ST have put a lot of interesting analog stuff in with the digital in their STM32 chips. Both the STM32MP1 and STM32F103 has dual 12-bit ADCs, so you can do simultaneous sampling or interleaved for increased speed. The STM32F303 series has up to four. The STM32FMP1 has dual DACs as well (the STM32F103 series has at most one, but the Blue Pill has none due to using a low pin-count package). Now, I've just been dabbling with this embedded stuff in my spare time for a wee while now, but it seems ST is pushing hard and on the rise. *: now their hardware abstraction layer, the HAL library, leaves quite a bit to be desired, but it's nice to get a starting point for newbies.
- TickleSteve 8y ago
  ST is quite probably the market leader for embedded micros (though NXP may be getting there). They're hardly the up and coming underdog, they're the 800lb gorilla in the market and the things you mention are pretty much par for the course. This combined A7+M4 device is unusual, but is simply a cost saving over what would simply be an A7 device serially attached to an M4 (for example). There does not seem to be any new features here other than the cost saving from combining them.
  - zokier 8y ago
    > ST is quite probably the market leader for embedded micros (though NXP may be getting there). This report from 2016 puts NXP at twice the marketshare over STmicro who are sitting steadily in the fifth place: https://epsnews.com/2017/05/01/nxp-tops-microcontroller-supplier-ranking/ https://epsnews.com/2017/05/01/nxp-tops-microcontroller-supp... Although at least part of the sales volume difference can be explained by NXP having had more expensive i.MX range available (and others), so in terms of chips sold they might be closer to each other. > This combined A7+M4 device is unusual I'm not sure if I'd say that, previously NXP did the exact same thing with i.MX7, and TI with their AM5x. And of course don't forget the classic AM3x which had PRUs filling part of the same role.
ChuckMcM 8y ago
Ok then, that is pretty cool. Can't wait to get the Discovery kit [1]. Pretty much a 'super chumby' :-). Next up the 1K price point for these things. [1] https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eval-tools/stm32-mcu-mpu-eval-tools/stm32-discovery-kits/stm32mp157c-dk2.html https://www.st.com/content/st_com/en/products/evaluation-too...
- duskwuff 8y ago
  > Next up the 1K price point for these things. $9.80 @10ku for the part on the Discovery. Not shipping yet, but other parts in the STM32MP family are. https://www.st.com/content/st_com/en/products/microcontrollers-microprocessors/stm32-arm-cortex-mpus/stm32mp1-series/stm32mp157/stm32mp157c.html https://www.st.com/content/st_com/en/products/microcontrolle...
  - deleted 8y ago
    [deleted]
  - zokier 8y ago
    And the cheapest part is $4.848, that is pretty damn affordable. Many of STM32F4 are more expensive than that!
TD-Linux 8y ago
The (optional) GPU is a Vivante core, which is great because it's supported by free software drivers and Mesa support. Given the generally good free software support that ST gives, plus the mainline Linux support landing over a year early, this looks like a pretty fun part to play with.
joezydeco 8y ago
"Supports" Android is not the same as "running it without wanting to throw it out a window".
- pjmlp 8y ago
  In any case a device able to run a standard Linux distribution is much better using OpenJDK than having to deal with Android J++.
  - monocasa 8y ago
    Last time I checked, it was such an early port OpenJDK for AArch32 didn't even support a JIT yet.
    - pjmlp 8y ago
      Then check again, as OpenJDK has a much better ARM support nowadays. In any case, the beauty of standard Java is that the OpenJDK is not the only option available for targeting ARM, there are other vendors offering Java compliant solutions. And by being regular Linux distributions, there are also other programming languages available for those that don't like coffee based languages.
      - monocasa 8y ago
        > Then check again, as OpenJDK has a much better ARM support nowadays. I just checked, and it by default ships with Zero in interpreter mode, with Azul's AArch32 work still being pre beta and not even fully integrated into master yet. > In any case, the beauty of standard Java is that the OpenJDK is not the only option available for targeting ARM, there are other vendors offering Java compliant solutions. I'm not going to pay for a solution for a $5 chip.
        pjmlp 8y ago
        Then you get what you pay for.
kbumsik 8y ago
The Discovery dev board [1] is pretty rich for the official $69 baord. Gigabit eth, audio, HDMI, 4 USB-A + 1 USB-C, Arduino/RPi expansion connectors, and of course a ST-Link (can it debug multicore Cortex-A7 btw?) I hope it would get a great open-source support. [1]: https://www.st.com/resource/en/data_brief/stm32mp157c-dk2.pdf https://www.st.com/resource/en/data_brief/stm32mp157c-dk2.pd...
dmitrygr 8y ago
If it has their insanely broken i2c implementation, it wouldn't matter if it cures cancer. Look into the linux driver for stm32 i2c driver. more curses per comment than any other driver. they are ALL deserved.
- ohazi 8y ago
  iirc, their SPI hardware is also a little wonky. The designer seems to have assumed that the only thing you'd ever want to read from in receive-only mode is an SPI flash chip, so it eagerly tries to fill the receive buffer every time you read. So you might be trying to do a single word read from some device, but you'll see a dozen reads on a scope trace. The only way that I've found to get around this is to run a dummy transmitter. Transmit as many zero bytes as you'd like to read, and then it'll run the receiver in lock-step. This would have all been reasonable if it were documented, but it wasn't at the time.
  - scoutt 8y ago
    While I agree that I2C is mostly broken and filled with workarounds (at least in the STM32F103x family), the SPI in master mode (as I understand you are referring to) works fairly well. To receive data you have to send clock pulses. Sending clock pulses also means that you are transmitting (zeroes in your case), but there is no way to escape from that since it's the way SPI works. SPI in STM32 is very precise with timings and general behavior. Take a look on how some seasoned users implement SPI to do VGA graphics: https://www.artekit.eu/vga-output-using-a-36-pin-stm32/ https://www.artekit.eu/vga-output-using-a-36-pin-stm32/
    - dmitrygr 8y ago
      I think the parent was talking about using SPI in bidirectional mode (one shared wire for both tx and rx). In that case indeed it is hard to only read a fixed small number of bytes
jeshwanth 8y ago
MPU supports Linux? Can somebody explain how they are doing this without MMU? Is it a security issue or complex compared to MMU?
- aceperry 8y ago
  They're calling the MPU: Microprocessor Unit, not a memory protection unit. The Cortex A7 has the MMU. BTW, there are some linux distros that are made to run on processors without mmu's. Look at uClinux and NOMMU Linux.

91 points by conductor 8y ago

mkesper 8y ago

I'd like to read the site but it doesn't allow it without accepting their tracking stuff. This is stupid.

monocasa 8y ago

I should hope so. The RPi2 is a quad core A7.

kbumsik 8y ago
You should know that the computation capabilities is not the only factor of the industrial embedded system and that chip does not even look at it. It much more focused on real-time capabilities and hardware control. Notable examples are 1. Built-in Cortex M4 microcontroller 2. RPi doesn't have ADCs but STM32MP1 got 16-bit ADCs and a sigma-delta modulator. 3. It's got 5V-tolerant GPIO whereas RPis are not 4. Best-in-class timers for PWM and quadrature encoders.
- monocasa 8y ago
  The title has changed since I posted. It was something to the effect of "ST Micro Cortex-A7 supports Linux and Android". Which is sort of 'no shit, of course an A7 is easy to port Linux to.' Yes, I know that an RPi isn't the best microcontroller. My last job had me as the lead for a proprietary RTOS for a custom robotics system. In fact if you go into the STM32F docs for the SSI controller where it calls the busy flag "unreliable", that was my contribution.

dvfjsdhgfv 8y ago

See their official press release here: https://www.st.com/content/st_com/en/about/media-center/press-item.html/p4140.html https://www.st.com/content/st_com/en/about/media-center/pres...

magicalhippo 8y ago

ST is pushing hard it seems. They bought Atollic and made their TrueSTUDIO IDE free, and while it's Eclipse based it's pretty easy to set up and get going at least. They've got a plugin for it, STM32CubeMX, which helps you configure and generate initialization code* for the peripherals and clock. Having started out with Arduino I've lately been having fun with the STM32F103 "Blue Pill" boards. Like with this STM32MP1, ST have put a lot of interesting analog stuff in with the digital in their STM32 chips. Both the STM32MP1 and STM32F103 has dual 12-bit ADCs, so you can do simultaneous sampling or interleaved for increased speed. The STM32F303 series has up to four. The STM32FMP1 has dual DACs as well (the STM32F103 series has at most one, but the Blue Pill has none due to using a low pin-count package). Now, I've just been dabbling with this embedded stuff in my spare time for a wee while now, but it seems ST is pushing hard and on the rise. *: now their hardware abstraction layer, the HAL library, leaves quite a bit to be desired, but it's nice to get a starting point for newbies.

TickleSteve 8y ago
ST is quite probably the market leader for embedded micros (though NXP may be getting there). They're hardly the up and coming underdog, they're the 800lb gorilla in the market and the things you mention are pretty much par for the course. This combined A7+M4 device is unusual, but is simply a cost saving over what would simply be an A7 device serially attached to an M4 (for example). There does not seem to be any new features here other than the cost saving from combining them.
- zokier 8y ago
  > ST is quite probably the market leader for embedded micros (though NXP may be getting there). This report from 2016 puts NXP at twice the marketshare over STmicro who are sitting steadily in the fifth place: https://epsnews.com/2017/05/01/nxp-tops-microcontroller-supplier-ranking/ https://epsnews.com/2017/05/01/nxp-tops-microcontroller-supp... Although at least part of the sales volume difference can be explained by NXP having had more expensive i.MX range available (and others), so in terms of chips sold they might be closer to each other. > This combined A7+M4 device is unusual I'm not sure if I'd say that, previously NXP did the exact same thing with i.MX7, and TI with their AM5x. And of course don't forget the classic AM3x which had PRUs filling part of the same role.

ChuckMcM 8y ago

Ok then, that is pretty cool. Can't wait to get the Discovery kit [1]. Pretty much a 'super chumby' :-). Next up the 1K price point for these things. [1] https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eval-tools/stm32-mcu-mpu-eval-tools/stm32-discovery-kits/stm32mp157c-dk2.html https://www.st.com/content/st_com/en/products/evaluation-too...

duskwuff 8y ago
> Next up the 1K price point for these things. $9.80 @10ku for the part on the Discovery. Not shipping yet, but other parts in the STM32MP family are. https://www.st.com/content/st_com/en/products/microcontrollers-microprocessors/stm32-arm-cortex-mpus/stm32mp1-series/stm32mp157/stm32mp157c.html https://www.st.com/content/st_com/en/products/microcontrolle...
- deleted 8y ago
  [deleted]
- zokier 8y ago
  And the cheapest part is $4.848, that is pretty damn affordable. Many of STM32F4 are more expensive than that!

TD-Linux 8y ago

The (optional) GPU is a Vivante core, which is great because it's supported by free software drivers and Mesa support. Given the generally good free software support that ST gives, plus the mainline Linux support landing over a year early, this looks like a pretty fun part to play with.

joezydeco 8y ago

"Supports" Android is not the same as "running it without wanting to throw it out a window".

pjmlp 8y ago
In any case a device able to run a standard Linux distribution is much better using OpenJDK than having to deal with Android J++.
- monocasa 8y ago
  Last time I checked, it was such an early port OpenJDK for AArch32 didn't even support a JIT yet.
  - pjmlp 8y ago
    Then check again, as OpenJDK has a much better ARM support nowadays. In any case, the beauty of standard Java is that the OpenJDK is not the only option available for targeting ARM, there are other vendors offering Java compliant solutions. And by being regular Linux distributions, there are also other programming languages available for those that don't like coffee based languages.
    - monocasa 8y ago
      > Then check again, as OpenJDK has a much better ARM support nowadays. I just checked, and it by default ships with Zero in interpreter mode, with Azul's AArch32 work still being pre beta and not even fully integrated into master yet. > In any case, the beauty of standard Java is that the OpenJDK is not the only option available for targeting ARM, there are other vendors offering Java compliant solutions. I'm not going to pay for a solution for a $5 chip.
      - pjmlp 8y ago
        Then you get what you pay for.

kbumsik 8y ago

The Discovery dev board [1] is pretty rich for the official $69 baord. Gigabit eth, audio, HDMI, 4 USB-A + 1 USB-C, Arduino/RPi expansion connectors, and of course a ST-Link (can it debug multicore Cortex-A7 btw?) I hope it would get a great open-source support. [1]: https://www.st.com/resource/en/data_brief/stm32mp157c-dk2.pdf https://www.st.com/resource/en/data_brief/stm32mp157c-dk2.pd...

dmitrygr 8y ago

If it has their insanely broken i2c implementation, it wouldn't matter if it cures cancer. Look into the linux driver for stm32 i2c driver. more curses per comment than any other driver. they are ALL deserved.

ohazi 8y ago
iirc, their SPI hardware is also a little wonky. The designer seems to have assumed that the only thing you'd ever want to read from in receive-only mode is an SPI flash chip, so it eagerly tries to fill the receive buffer every time you read. So you might be trying to do a single word read from some device, but you'll see a dozen reads on a scope trace. The only way that I've found to get around this is to run a dummy transmitter. Transmit as many zero bytes as you'd like to read, and then it'll run the receiver in lock-step. This would have all been reasonable if it were documented, but it wasn't at the time.
- scoutt 8y ago
  While I agree that I2C is mostly broken and filled with workarounds (at least in the STM32F103x family), the SPI in master mode (as I understand you are referring to) works fairly well. To receive data you have to send clock pulses. Sending clock pulses also means that you are transmitting (zeroes in your case), but there is no way to escape from that since it's the way SPI works. SPI in STM32 is very precise with timings and general behavior. Take a look on how some seasoned users implement SPI to do VGA graphics: https://www.artekit.eu/vga-output-using-a-36-pin-stm32/ https://www.artekit.eu/vga-output-using-a-36-pin-stm32/
  - dmitrygr 8y ago
    I think the parent was talking about using SPI in bidirectional mode (one shared wire for both tx and rx). In that case indeed it is hard to only read a fixed small number of bytes

jeshwanth 8y ago

MPU supports Linux? Can somebody explain how they are doing this without MMU? Is it a security issue or complex compared to MMU?

aceperry 8y ago
They're calling the MPU: Microprocessor Unit, not a memory protection unit. The Cortex A7 has the MMU. BTW, there are some linux distros that are made to run on processors without mmu's. Look at uClinux and NOMMU Linux.