USB OTG Boot
#1
I was looking at the user manual and it says the USB OTG Boot is possible for the system code. It does not describe now this works.

I was wonder is the pine64 strapped to support booting off UBS OTG. If not is there a way to change the boot strap to do that.

I tried looking for a schematic for the pine64 but there does not seem to be one.
  Reply
#2
(01-09-2016, 09:53 PM)devilsclaw Wrote: I was looking at the user manual and it says the USB OTG Boot is possible for the system code. It does not describe now this works.

I was wonder is the pine64 strapped to support booting off UBS OTG. If not is there a way to change the boot strap to do that.

I tried looking for a schematic for the pine64 but there does not seem to be one.

Based on the Allwinner original boot practice the USB OTG boot process till there and may works. However, I have not try out.
  Reply
#3
(01-09-2016, 09:53 PM)devilsclaw Wrote: I tried looking for a schematic for the pine64 but there does not seem to be one.

Simple rule of thumb: don't trust a vendor that doesn't publish at least schematics. It's really that simple Smile

FEL mode should work on the A64 but if it really works on Pine64 still has to be confirmed (USB OTG is normally used together with Mini or Micro USB where an ID pin exists). The question has been asked already 4 weeks ago but the Pine guys did nothing to answer: http://forum.pine64.org/showthread.php?tid=44 

I would call this already lack of support.
  Reply
#4
Yes, the missing schematics document makes everything unnecessarily complicated, but I hope that it will be available eventually. So far I can only speculate that the Micro-USB connector is probably just used for powering the device, and one of the USB host connectors is actually routed to the USB OTG hardware. It means that for booting over USB, we might need an adapter similar to this one - http://www.ebay.com/itm/131373127233 (I have actually ordered it) and a USB Mini-B cable to connect it to the PC. The USB boot procedure is described here: http://linux-sunxi.org/FEL/USBBoot

I'm one of the guys who may probably receive a Pine64 board from the first developer's batch. When/if it arrives, I will try to make sure that the USB boot works and that the U-Boot bootloader is usable and mainlined Smile
  Reply
#5
Yes, micro USB is only used for DC-IN (weird decision in my humble opinion since the Remix folks use a 3A PSU for their Remix Mini and speak about 10W consumption) and regarding the USB OTG port according to the aforementioned thread:


Quote:The micro USB port type B is 5 pin which has ID pin to determine OTG or Host. However, the Pine64 lower USB port is type A and 4 pin which means lacking ID signal. Currently the schematic lets the ID pin float with a pull high resister. In current Pine64 Android OS, we manually set the lower USB port to host mode instead of determine by ID pin.

We will see what that means.
  Reply
#6
Quote:Yes, micro USB is only used for DC-IN (weird decision in my humble opinion)
Since the A64 SoC only supports one USB host and one USB OTG, they had a choice between having two USB host connectors or having one regular USB host connector and one mini/micro connector for OTG.

Two USB host connectors are useful for plugging USB keyboard and USB mouse without any extra adapters and that's probably what the general public prefers.

Yes, DC-IN could alternatively use a barrel plug. But USB micro connector is the Raspberry Pi approach, which allows to use cellphone chargers instead of a dedicated power adapter. Admittedly this can lead to reliability issues if people start using shitty chargers or bad USB cables.
  Reply
#7
I agree that choosing 2 type A receptacles is more user-friendly. But since it's almost impossible to provide more than 10W through micro USB and as you already said shitty chargers and cables lying around will be used many Pine64 users will have to learn the hard way that they need a powered USB hub to connect external devices (like it's the case with Raspberry Pi often). Something that will add to the total costs significantly.

I would believe the Remix Mini makers (also based on A64 with the same connector choices) chose a 3A/5V PSU with barrel plug for a reason and I don't believe the consumption numbers provided in the wiki are close to realistic: http://wiki.pine64.org/index.php/Main_Page#Power_Usage
  Reply
#8
Quote:However, the Pine64 lower USB port is type A and 4 pin which means lacking ID signal. Currently the schematic lets the ID pin float with a pull high resister.
Basically, there is no ID pin in such setup and there is nothing to pull up or down.

Allwinner does not assign any dedicated ID pin for USB OTG and the BROM code does not have any checks for it (unless A64 introduces something new). Various Allwinner devices assign different pins to the OSB OTG ID pin and this is configured in the FEX or DTS. This is a purely software thing, used by the USB OTG driver. And if there is no hardware ID pin routed to the external connectors, then the DTS file is not going to have any ID pin information.

Quote:I agree that choosing 2 type A receptacles is more user-friendly. But since it's almost impossible to provide more than 10W through micro USB and as you already said shitty chargers and cables lying around will be used many Pine64 users will have to learn the hard way that they need a powered USB hub to connect external devices (like it's the case with Raspberry Pi often). Something that will add to the total costs significantly.

I would believe the Remix Mini makers (also based on A64 with the same connector choices) chose a 3A/5V PSU with barrel plug for a reason and I don't believe the consumption numbers provided in the wiki are close to realistic: http://wiki.pine64.org/index.php/Main_Page#Power_Usage
We will see whether the AXP803 PMIC is able to cope with bad chargers and tolerate significant voltage drop. Maybe there is actually nothing to worry about. But yes, the power consumption estimates look rather naive.
  Reply
#9
(01-10-2016, 05:45 AM)Andrew2 Wrote:
(01-09-2016, 09:53 PM)devilsclaw Wrote: I tried looking for a schematic for the pine64 but there does not seem to be one.

Simple rule of thumb: don't trust a vendor that doesn't publish at least schematics. It's really that simple Smile

FEL mode should work on the A64 but if it really works on Pine64 still has to be confirmed (USB OTG is normally used together with Mini or Micro USB where an ID pin exists). The question has been asked already 4 weeks ago but the Pine guys did nothing to answer: http://forum.pine64.org/showthread.php?tid=44 

I would call this already lack of support.

As mentioned earlier, we will publish the Pine A64 schematic, but not Gerber file. The schematic will be publish when we start making the first batch delivery on February. We prefer to publish the schematic version that same as production board. Deliver several earlier versions try to satisfy some curiosity will end up more confusion.

(01-10-2016, 08:00 AM)ssvb Wrote:
Quote:Yes, micro USB is only used for DC-IN (weird decision in my humble opinion)
Since the A64 SoC only supports one USB host and one USB OTG, they had a choice between having two USB host connectors or having one regular USB host connector and one mini/micro connector for OTG.

Two USB host connectors are useful for plugging USB keyboard and USB mouse without any extra adapters and that's probably what the general public prefers.

Yes, DC-IN could alternatively use a barrel plug. But USB micro connector is the Raspberry Pi approach, which allows to use cellphone chargers instead of a dedicated power adapter. Admittedly this can lead to reliability issues if people start using shitty chargers or bad USB cables.

Whether using barrel plug or micro SD connector was my struggle when making the DC input plug. The same concern of people using shitty chargers is  and still my main concern of choosing microSD.  However, i finally gave in and decided on microSD based on following two reason.

1. There are different type of barrel plug dimension and the most common is 5x2.1mm type. However, this type of plug are use for +12V application such as network camera. We don't want to keep receiving "dead of arrival" "burned" boards due to some one just keep plug in 12V power supply into Pine A64. There is no such concern using microUSB socket.
2. If we select an unpopular one to avoid answer 1, this can become inconvenient due to cannot get them on the shelve and may keep blame us try to make money out of selling power supply.

Noted on microUSB cannot carry more current compare to barrel plug.
  Reply
#10
The reason why I was trying to looking at a schematic is because I got the dev board yesterday and I'm looking into starting to develop for it. Not having to pull the sdcard every time I make a simple change would be nice. I don't want to do development on the pine its self since the sdcard could get corrupt while doing kernel development or the system might become un-bootable. If the dev board is different then the other ones coming out in February then that schematic might be useless to me since I am working on the dev board. The dev people need the schematic that belongs with there boards. there should be no confusion if it is released under the wiki designated for the dev board. Also I don't see any TODO list or work that needs done in the wiki.

(01-10-2016, 12:45 PM)tllim Wrote:
(01-10-2016, 05:45 AM)Andrew2 Wrote:
(01-09-2016, 09:53 PM)devilsclaw Wrote: I tried looking for a schematic for the pine64 but there does not seem to be one.

Simple rule of thumb: don't trust a vendor that doesn't publish at least schematics. It's really that simple Smile

FEL mode should work on the A64 but if it really works on Pine64 still has to be confirmed (USB OTG is normally used together with Mini or Micro USB where an ID pin exists). The question has been asked already 4 weeks ago but the Pine guys did nothing to answer: http://forum.pine64.org/showthread.php?tid=44 

I would call this already lack of support.

As mentioned earlier, we will publish the Pine A64 schematic, but not Gerber file. The schematic will be publish when we start making the first batch delivery on February. We prefer to publish the schematic version that same as production board. Deliver several earlier versions try to satisfy some curiosity will end up more confusion.

(01-10-2016, 08:00 AM)ssvb Wrote:
Quote:Yes, micro USB is only used for DC-IN (weird decision in my humble opinion)
Since the A64 SoC only supports one USB host and one USB OTG, they had a choice between having two USB host connectors or having one regular USB host connector and one mini/micro connector for OTG.

Two USB host connectors are useful for plugging USB keyboard and USB mouse without any extra adapters and that's probably what the general public prefers.

Yes, DC-IN could alternatively use a barrel plug. But USB micro connector is the Raspberry Pi approach, which allows to use cellphone chargers instead of a dedicated power adapter. Admittedly this can lead to reliability issues if people start using shitty chargers or bad USB cables.

Whether using barrel plug or micro SD connector was my struggle when making the DC input plug. The same concern of people using shitty chargers is  and still my main concern of choosing microSD.  However, i finally gave in and decided on microSD based on following two reason.

1. There are different type of barrel plug dimension and the most common is 5x2.1mm type. However, this type of plug are use for +12V application such as network camera. We don't want to keep receiving "dead of arrival" "burned" boards due to some one just keep plug in 12V power supply into Pine A64. There is no such concern using microUSB socket.
2. If we select an unpopular one to avoid answer 1, this can become inconvenient due to cannot get them on the shelve and may keep blame us try to make money out of selling power supply.

Noted on microUSB cannot carry more current compare to barrel plug.
  Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Pine Board using linux stuck during boot sequence ktaragorn 4 711 03-30-2019, 06:48 AM
Last Post: ktaragorn
  Secure boot & OTP efuse program devangpanchal90 0 595 05-25-2018, 01:59 AM
Last Post: devangpanchal90
  boot process for pine a64 awaysu 1 1,254 01-24-2018, 05:09 AM
Last Post: xalius
  Can't boot headless after running update_uboot.sh Borglesnorgle Williams 2 624 08-17-2017, 04:08 AM
Last Post: Borglesnorgle Williams
Exclamation Pine A64 Plus Fails to Boot grobbs 35 5,882 06-28-2017, 08:53 AM
Last Post: sarav_sara
  Boot issues: What todo when you muck up your FSTAB file Dagremote 1 825 04-16-2017, 10:28 PM
Last Post: pfeerick
Question Pine64 cannot boot jamiechang917 6 2,180 04-16-2017, 10:21 PM
Last Post: pfeerick
  U-Boot for A64 git longsleep 38 21,492 03-21-2017, 01:59 PM
Last Post: longsleep
  OpenWRT supports ARMv8 - arm64, u-boot problem? rgdonato 4 1,816 03-20-2017, 03:59 PM
Last Post: rgdonato
  How to boot alternative kernel image with u-boot? zhouer 3 2,107 06-27-2016, 04:15 AM
Last Post: ssvb

Forum Jump:


Users browsing this thread: 1 Guest(s)