Linux mainlining effort

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The purpose of this page is to try and define sub-goals and milestones for the mainlining effort, containing goals and sub-goals with milestones for adding Allwinner support in the upstream mainline Linux Kernel.

It is very important to note that this is intended as a rough set of minimal goals - it is not meant to collide with the huge effort of rewriting major drivers!



The idea is to submit the code needed to run the Linux kernel on Allwinner SoCs upstream, ie. to the official Linux kernel.

This can be achieved by following the concept outlined in the Your new ARM SoC Linux support check-list! article published by Thomas Petazzoni from Free Electrons.[1][2]

Where relevant, I have attempted to include who is currently working on an item, mostly separate from any particular mainlining goal.


The Mainline Kernel howto contains the currently used repositories for the mainlining process. The uBoot repository and toolchain is described in the uBoot howto.

Merged into 3.8

Related merges: [1], [2]

Added board support: Cubieboard, A13-OLinuXino

Merged into 3.9

  • PINCTRL driver
  • GPIO-lib based driver

Related merges: [3]

Added Board Support: Miniand_Hackberry

Merged into 3.10

  • LED support
  • Clock driver
  • Complete UART support

Related merges: [4], [5], [6]

Added Board Support: Pineriver_H24

Merged into 3.11

  • IRQ support for the PIO
  • I2C Driver
  • EMAC Driver
  • A10s support

Related merges: [7], [8], [9], [10], [11], [12]

Added board support: Olimex A10s-OLinuXino-Micro

Merged into 3.12

  • A31 support
    • Basic SoC + GPIO
    • Clock support
  • A20 support
    • Basic SoC + GPIO
    • Clock support
  • A10s clocks
  • Clock Source and Clock Event rework
  • Watchdog driver

Related merges: [13], [14], [15], [16], [17], [18]

Added board support: A31 EVB, A20-OLinuXino-Micro, Cubieboard2, Mele A1000

Merged into 3.13

  • SID Driver
  • I2C for A20
  • sunxi_defconfig
  • Bug fixes [19]

Added board support: Cubietruck

Merged into 3.14

  • A31
    • Reset Controller Support
    • SMP
  • A20
    • SMP (via PSCI)
    • External clock outputs
  • High Speed Timers
  • RTC driver (A10/A20) (commit)
  • RTP (DT only)
  • GMAC support in stmmac driver
  • AP6210 WiFi (BCM43362) support in brcmfmac driver

Related merges: [20], [21], [22], [23], [24]

Added board support: Olimex A13-OLinuXino-Micro (commit)

Merged into 3.15

  • All SoCs
    • SPI
  • A10/A10s/A13/A20
    • OHCI
    • EHCI
  • A10/A20
    • AHCI
  • A20/A31
    • NMI controller
  • A20
    • GMAC
  • A31
    • I2C

Related merges: [25], [26], [27], [28], [29], [30], [31]

Added board support: LinkSprite_pcDuino, Inet 97f, A10-OLinuXino-LIME

Merged into 3.16

  • All
    • AXP20x support
      • APX20x power enable key driver
    • MMC support
  • A31
    • USB support
    • PRCM
    • SMBus Regmap
    • Special Pins Muxer
    • P2WI Controller
  • A10
    • Touchscreen controller [32]
    • Touchscreen controller temperature sensor [33]

Related Merges: defconfig-for-3.16, drivers-for-3.16, dt-for-3.16, soc-for-3.16, usb-3.16-rc1, pinctrl-v3.16-1, clk-for-linus-3.16, clk-for-linus-3.16-part2, mmc-updates-for-3.16-rc1, mfd-for-linus-3.16, regulator-v3.16, input-for-linus

Added board support: Mele M9, R7

Merged into 3.17

  • A10/A20
    • IR driver
  • A31
    • PIO/R_PIO external interrupts
    • DMAengine
    • GMAC
  • A23
    • Timers, UARTs, initial bringup
    • Basic clocks
    • PIO/R_PIO drivers

Related merges: clk-for-linus-3.17, mfd-for-linus-3.17, pinctrl-v3.17-1, soc-for-3.17, dt-for-3.17, slave-dma for-linus, v4l_for_linus,

Added Board Support: Merrii Hummingbird A31, BA10, LinkSprite pcDuino V3, Ippo q8h

Planned for 3.18

  • A23
    • DT for remaining supported peripherals

Work In Progress

Core Stuff

  • DMAengine driver for A10/A10s/A20 (sun4i/sun5i/sun7i) (WiP: Emilio Lopez (turl)) [35]
    • DMAengine driver handles slave DMA clients including SPI, EMAC, USB, I2S, HDMI audio, and NAND
    • Highest priority is to implement slave SG transfers (SPI driver as a proof of concept and test target), cyclic transfers (for audio clients)
    • These SoCs have two modes of operations: Normal and Dedicated. The dedicated mode looks a lot like how the A31 DMA controller works, though it only supports mem2dev transfers
  • DMAengine driver for A23 (shared with A31) (WiP: Chen-Yu Tsai (wens))
  • Watchdog driver for A31/A23 (WiP: Chen-Yu Tsai (wens))
  • AXP209 driver (WiP: Carlo Caione (ccaione)) [36]
    • PowerSupply/Battery driver for AXP209 (WiP: Bruno Prémont (bonbons)) [37]
  • AXP221 driver (WiP: Boris Brezillon (bbrezillon)) [38]

Major drivers

  • NAND Driver (WiP: Boris Brezillon (bbrezillon)) patch-v4
  • A31 Audio Codec driver (WiP: Maxime Ripard (mripard))
    • A31 PLL2 and module 1 clocks
    • Cyclic DMA transfers
    • ASoC driver
    • Much more complex and signficantly different from the other audio codecs IPs found in the other Allwinner SoCs (A23 included)
  • A20 Audio Codec (WiP: Jon Smirl) [39]

Minor drivers

  • IIO LRADC driver (WiP: Carlo Caione (n01)) Input LRADC driver (WiP: Hans de Goede (hansg)) [40]
  • PWM Driver (WiP: Alexandre Belloni) [41]
  • Security System (Crypto Engine) (WiP: Corentin Labbe (Montjoie)) [42]
    • Hardware Pseudo Random Number Generator
    • Checksumming (MD5, SHA1)
    • Crypto (AES, DES, 3DES)

Timeouts ? (No code has ever been submitted to mainline, current status unknown)

  • USB OTG Driver (WiP CHen-Yu Tsai (wens))
    • It seems to actually be a Mentor Graphics Inventra USB Controller (musb), that already support for it in mainline kernel, so it only needs a thin layer to adapt it to sunxi. Moreover, it's already supporting the PIO mode, so we could avoid relying on DMA to merge it. (Thanks to Arnd Bergmann for noticing)
    • irc user jukivili works on getting this driver to work with sunxi-3.4
    • Status 2013-10-02:
      • OTG requires more work. Mode detection is working, but have not yet figured out how to reset MUSB core and hardware from host-mode to peripheral and other way around.
      • Mode detection/USB-PHY stuff probably needs to be moved to new USB-PHY driver as is done with other MUSB hardware drivers.
  • Transport Stream (WiP: woprr)
  • CAN (WiP: Peter Chen [43] / restored code dump: [44])

Left to be done


  • Audio
    A23 SDK has aSoC drivers for the first three (drivers below depend on cyclic DMA transfers which need to be implemented first):
    • Audio Codec (initial code submitted)
    • IIS/I2S (Audio transport)
    • SPDIF (Audio transport)
    • AC97 Interface
  • CSI (Camera Input)
  • PS/2 (Keyboard/Mouse)
  • Smart Card Reader
  • Keypad
  • One wire (A31, A23)



  • Memory Stick (has anybody actually got this hardware connected and a memory stick?)
  • TV Decoder (Analog in, no driver, no datasheet)
  • PATA (Old tech, while still interesting for Compact Flash, possibly removed from A20, though A20 memory map still mentions it)
  • GPS backend IP (Only A10, not much interesting, as all modern GPS recivers have MCU with UART output, no documentation)


These are too far off the track third party drivers making it unlikely they will ever get accepted mainline.

  • Mali driver (will not happen unless libv gets a proper lima driver out)

Related but separate

  • Device-specific drivers


  2. Your New ARM SoC Linux Support Check-List – ELCE 2012

See also

External Links

How to upstream

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