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Ouya (ouya-ouya)

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Revision as of 22:05, 19 April 2019 by Decatf (talk | contribs) (Add notes about audio)
Ouya, Inc. Ouya
Ouya
Ouya
Manufacturer Ouya, Inc.
Name Ouya
Codename ouya_1_1
Released 2013
Hardware
Chipset Nvidia Tegra 3
CPU 4x 1.7 GHz Cortex-A9
GPU Nvidia GeForce ULP
520 MHz (12.48 GFLOPS)
Display 1x HDMI
Storage 8/16 GB
Memory 1 GB
Architecture armv7
Software
Original software Android
postmarketOS
Category testing
Pre-built images no
Mainline partial
Unixbench Whet/Dhry score 1450.2
Features
Flashing
Partial
USB Networking
Works
Internal storage
No data
SD card
No data
Multimedia
3D Acceleration
No data
Audio
No data
Camera Flash
No data
Connectivity
WiFi
Works
Bluetooth
Works
NFC
No data
Miscellaneous
FDE
Partial
USB OTG
No data
HDMI/DP
No data
Sensors
Magnetometer
No data
Ambient Light
No data
Proximity
No data
Hall Effect
No data
Haptics
No data
Barometer
No data


Contributors

  • rendeko
  • ryang2678 (Decatf)
  • ollieparanoid

Maintainer(s)

  • rendeko


Kernel

We avoid flashing directly to the device as a corrupted kernel would irreversibly brick the Ouya due to the locked bootloader. We use a tool called Ouya BootMenu (source) that allows us to run the postmarketOS kernel through a kexec method. This implements an extra failsafe to prevent bricking and in theory allows dualbooting and kernel development.

Audio

  • Audio on the downstream kernel is untested.
  • Audio on the mainline kernel is not working.

In the mainline kernel, the hdmi driver is located in drivers/video/tegra/dc/hdmi.c. This implementation reads the HDMI audio format a scratch register when the hdmi interrupt is asserted. The Ouya does not appear to trigger an interrupt. The scratch register does not appear to have valid data either. The downstream kernel does not appear to use this method to configure audio. Further examination of the downstream kernel to determine how audio is configured.

Ethernet

A random MAC address is generated by the kernel at each boot. This is because the smsc9500 Ethernet device does not have a valid mac address stored in EEPROM. To set a consistent MAC address, create the file /etc/udev/rules.d/99-mac-address.rules with the following udev rule.

ACTION=="add", SUBSYSTEM=="net", KERNEL=="eth0", RUN+="/sbin/ip link set dev %k address f6:23:f0:42:98:cf"

Radio

  • The Ouya uses a BCM4330 radio chip for wifi and bluetooth. The downstream and mainline kernel use the same wifi firmware. The firmware shipped with the device is the only known firmware to work with the Ouya. The BCM4330 firmware in linux-firmware does not work.
  • Two later releases (the completely white special edition and completely black 2nd generation) allegedly use a BCM4334 chipset. This needs to be implemented and tested at a future date.

Display Resolution

On the mainline kernel, display resolutions above 1280x720 are glitchy. The GPU is dependent on memory bandwidth but EMC scaling is not implemented in mainline. The Ouya bootloader sets the memory to 400 Mhz. Higher display resolutions work a bit better when the memory is set to 800Mhz but it is still glitchy.

Other Notes

  • Splash screen doesn't appear
  • Hildon doesn't work?
  • USB booting needs to be tested


Installation

How to enter flash mode

1. Connect Ouya to PC

2. Use adb reboot recovery to enter recovery (or adb reboot bootloader to enter bootloader for fastboot commands)

pmbootstrap

TODO TODO: Work in progress, may be wrong. Only attempt for development

1. Flash CWM and Ouya BootMenu.

2. Turn on Ouya, then press the power button many times until it scrolls to Bootloader, and then wait until the boot menu disappears.

3. Run the following using pmbootstrap:

$ pmbootstrap init
$ pmbootstrap install --no-fde
$ pmbootstrap export
$ pmbootstrap flasher flash_rootfs
Note WARNING: This will create two partitions under system partition instead of one which won't allow you to use Normal Boot option in Ouya BootMenu

4. Reboot Ouya, then press the power button many times until it scrolls to Recovery, and then wait until CWM appears.

6. Using CWM menu options, mount /data partition.

7. Copy postmarketOS boot.img to /sdcard as altboot.img:

$ adb push /tmp/postmarketOS-export/boot.img-ouya-ouya /sdcard/altboot.img

8. Reboot Ouya, then press the power button many times until it scrolls to Alternate Boot, and then wait until postmarketOS appears.

Using data partition as rootfs

Note WARNING: Flashing to the userdata partition will overwrite all data on the device. Backup all data to another device before proceeding.

It is much more usable to flash rootfs to the data partition which is around 5.7GB in size.

Flashing to the data partition

Specify the partition to flash rootfs to with the --partition argument:

$ pmbootstrap flasher flash_rootfs --partition userdata

Copy postmarketOS boot.img to /system:

$ adb push /tmp/postmarketOS-export/boot.img-ouya-ouya /system/boot.img

Updating the kernel

When the apk package manager updates the kernel package (e.g. linux-ouya-ouya or linux-ouya-ouya-mainline) then the boot.img will be regenerated with the new kernel. Run the following commands on device to install the updated boot.img:

$ mkdir /system
$ mount /dev/mmcblk1p3 /system
$ cp /boot/boot.img-ouya-ouya /system/boot.img

Links