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The Nokia N900 is a Linux based smartphone from Nokia, which has been released in November 2009. It's sold with Maemo using a patched 2.6.28 kernel (adding board support and lots of drivers). Since then board support has been added to the mainline kernel and most hardware can be used with a current kernel. Details can be seen in the table below.

Kernel Status

also see: N900/Changelog


  • Green = Available
  • Yellow = Work in Progress (WIP), for docs: no documentation, but kernel code available
  • Red = Missing
  • Gray = Deprecated
  • Cyan = Not Available (N/A)
Chip Driver name Purpose Docs Driver Device Tree Firmware
Driver DTS
OMAP3430 System-on-chip OMAP34xx TRM Yes < 3.13 3.13
* Cortex A8 CPU ARM infocenter Yes < 3.13 3.13
* * ARMv7 Instruction set ARM infocenter Yes N/A
* * NEON Media Extensions ARM infocenter Yes N/A
* * Thumb Code compression ARM infocenter 2.6.12 N/A
* * Thumb2 Code compression ARM infocenter Yes 3.14-rc6 N/A
* * ThumbEE Instruction Set for JIT compilers ARM infocenter Yes N/A (Userspace: Java VM?)
* * VFP Floating-point coprocessor ARM infocenter 2.6.12 N/A
* cpuidle CPUidle C-states for RX-51 code v4.6-rc1 N/A
* cpufreq CPUfreq MPU OPP values (with overclock) for RX-51 code N/A N/A CPUfreq without overclock
* M-Shield AES omap-aes AES HW acceleration (needs updated X-Loader) code 2.6.37-rc1 3.13 3.13-rc3 (disabled)
* M-Shield SHA1/MD5 omap-sham SHA1 and MD5 HW acceleration code 2.6.35-rc1 4.2-rc1 4.1-rc2
* IOMMU omap-iommu OMAP3 IO Memory Management Unit OMAP34xx TRM Yes 3.15
* OMAP 3 Camera ISP omap3-isp OMAP3 Camera Chip Connection Bus OMAP34xx TRM 2.6.39-rc1 (broken) 4.1-rc1
* OMAP DSS omapdss Video HW abstraction layer OMAP34xx TRM Yes 3.15
* OMAP DRM omapdrm KMS video driver N/A 3.3-rc1 N/A
* TMS320 C64x tidspbridge DSP (also called IVA 2+) datasheet No (removed in v3.17-rc1 broken since 3.13-rc2) No
* * DSP patches for Maemo/N900 code WIP N/A
* PowerVR SGX530 pvrsrvkm omaplfb OpenGL ES and OpenVG acceleration kernel code (userspace is closed) Code exists, upstreaming not possible N/A
* OMAP Watchdog omap_wdt Watchdog OMAP34xx TRM 3.8 < 3.13 3.13
* OMAP MMC/SD/SDIO omap_hsmmc eMMC OMAP34xx TRM Yes < 3.13 3.13-rc3
* OMAP MMC/SD/SDIO omap_hsmmc SD/MMC card OMAP34xx TRM Yes < 3.13 3.13
* omap_hsmmc slot-name OMAP34xx TRM Yes WIP
* temp ti-soc-thermal OMAP34xx temperature sensor code v4.4-rc1 v4.4-rc1 v4.6-rc1
TI TWL4030 twl-core multifunction (I2C) TPS65950 TRM N/A < 3.13 3.13
*  ??? Audio part of TI TWL4030 Yes 3.13
* twl4030-vibra Vibrator part of TI TWL4030 Yes < 3.13 3.13
* rtc-twl Real-Time Clock part of TI TWL4030 Yes < 3.13 3.13
* twl4030_wdt Watchdog part of TI TWL4030 3.8 < 3.13 3.13
* twl4030_keypad Keypad part of TI TWL4030 2.6.33 3.14 3.15
* twl4030_pwrbutton Power Button part of TI TWL4030 Yes 3.14 3.14
* twl4030_madc Analog Digital Converter part of TI TWL4030 Yes 3.15 3.16
GPIO gpio-keys Camera button N/A Yes < 3.13 3.13
Taos TSL2563 tsl2563 Ambient light sensor datasheet 2.6.33 3.14 3.15
LP5523 leds-lp5523 LED driver documentation 2.6.37-rc2 3.13 3.13
Sony ACX565AKM panel-sony-acx565akm LCD panel code 2.6.35 3.15
TI TSC2005 tsc2005 Touchscreen controller datasheet 2.6.39-rc1 3.16 3.16
* Sysfs node for disabling device datasheet No N/A
WL1251 wl1251_spi wl1251 802.11b/g WiFi code 2.6.31 3.15-rc1 3.16 wl1251-fw.bin wl1251-nvs.bin
* Packet injection support code 3.14 N/A
* Permanent mac address code WIP N/A
* Bluetooth coexistence mode configuration code WIP N/A
Si4713 radio-si4713 si4713-i2c FM transmitter datasheet 2.6.32 3.19 3.19
TPA6130a2 snd-soc-tpa6130a2 Headphone amplifier datasheet 2.6.33 3.13-rc1 3.13
TLV320AIC3X snd-soc-tlv320aic3x Digital audio data serial ti.com 2.6.25 3.13 3.13
Board snd-soc-rx51 Sound SoC Wiring N/A Yes 3.16 3.16
* All sound alsa switches and channels In maemo fremantle kernel No N/A
GPIO gpio-keys Proximity sensor N/A Yes < 3.13 3.13
Phonet phonet Modem protocol code 2.6.28 N/A
HSI hsi Modem Bus Framework code 3.4-rc2 N/A
Omap SSI omap-ssi Synchronous Serial Interface code 3.16 3.16 3.16
Modem n900-modem modem PM etc. code 3.16 3.16 3.16
* ssi-protocol ssi_protocol HSI client driver used by N900 code 3.16 N/A
* cmt-speech cmt_speech HSI client driver used by N900 code 4.1-rc1 N/A
* TI NaviLink NL5350 GPS (via Phonet modem protocol) reveng Userspace gps2.c
* A-GPS Uses SUPL Client SUPL application: http://www.tajuma.com/supl/index.html
rx51_battery rx51_battery Battery design capacity, battery temperature code 3.8 3.17 3.19
bq27200 bq27x00_battery Battery monitor chip documentation 2.6.28 < 3.13 3.13
isp1707a isp1704_charger USB charger detector datasheet 2.6.37-rc1 3.14 3.15
bq24150a bq2415x_charger Battery charger documentation 3.8 3.14 3.15
OneNAND onenand omap2 Flash memory code 2.6.15 < 3.13 3.13
LIS302DL lis3lv02d_i2c lis3lv02d Accelerometers datasheet 2.6.32 4.1-rc1 4.1-rc1
ADP 1653 adp1653 Flash Torch datasheet 3.1-rc1 4.2-rc1 v4.6-rc1
STM VS6555 smiapp Front Webcam datasheet 3.4-rc4 (broken) 4.0-rc1 No No firmware needed
ET8EK8 et8ek8 Main Camera datasheet WIP (broken) No, depends on omap3isp Firmware was integrated into driver (it was only data structure)
AD5820 ad5820 Autofocus datasheet for AD5821, which may be similar WIP No, depends on omap3isp
BCM2048 hci_h4p Bluetooth old code No (removed in v3.18-rc1) 3.15 (staging) No bcmfw.bin
* radio-bcm2048 FM/RDS receiver old code 3.14 (staging) No
IR Diode on PWM GPIO ir-rx51 Infrared/CIR transmitter N/A 3.7-rc1 (broken since v3.8-rc4) No
omap3-rom-rng omap3-rom-rng OMAP3 ROM Random Number Generator support code 3.13-rc2 3.16 currently not needed

Kernel git repository for N900

There is git repository for upstream linux kernel with all N900 patches.


This git repository is used for development. All other git repositories on internet are older and does not contains all patches.

Kernel Compilation

export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabi-
make rx51_defconfig
make zImage modules

DT Kernel Compilation

Make sure this is enabled in the kernel configuration:


Compile Kernel, Modules and DTB file:

export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabi-
make zImage
make modules
make omap3-n900.dtb

Create combined kernel image by appending the DTB file:

cat arch/arm/boot/zImage arch/arm/boot/dts/omap3-n900.dtb > zImage

Install Modules:

make INSTALL_MOD_PATH=/mnt/target modules_install

root problems in recent mainline

In recent mainline (cca 3.16+), it is impossible to use nfsroot over usb0 device. There's patch from Tony Lindgren fixing that.

Also for some strange reason, mmcblk? devices do not work for root filesystem. They work fine when mounted during runtime.

Bluetooth Status in Mainline Kernel

The bluetooth driver is currently available in drivers/staging/nokia_h4p. There is a TODO file in that directory, which lists the code refactoring needed to get the driver out of staging.

Apart from the things listed in that TODO file, the driver also seems to reinvent the wheel concerning the uart port. Most code in the driver simply configures the omap serial port and duplicates code in drivers/tty/serial/omap-serial.c.

sre thinks, that the hci protocol extension code should be put into a file similar to drivers/bluetooth/hci_ll.c, which could be called drivers/bluetooth/hci_nokia.c (hci with nokia extensions). This would result in the protocol being available as hci_uart_proto for usage in a hci-uart driver.

A second driver would be needed, which would be similar to drivers/bluetooth/hci_ldisc.c with the following differences:

  • support for additional gpios
  • support to be instanciated from DT instead of hciattach
  • support for loading bluetooth hardware address from DT
  • support for automatical loading of bt firmware (see btusb.c)


For M-Shield AES acceleration is needed updated signed bootloader X-Loader. Without it M-Shield crashing. SHA1 and MD5 acceleration work also without updating bootloader.

More info on: http://maemo.org/community/maemo-developers/n900_aes_and_sha1-md5_hw_acceleration_drivers/
Files are reuploaded at TMO thread: http://talk.maemo.org/showthread.php?p=1478502#post1478502


Instead of booting the kernel directly from NOLO (which restricts you to using exactly one kernel), U-Boot can be used as second bootloader. The Maemo kernel can be appended to U-Boot to keep the existing Maemo installation working (U-Boot must be located at the location of the Maemo kernel). The resulting boot process will end up like this: NOLO -> U-Boot -> Kernel.

Pali Rohár has been working on getting the N900 support into the mainline U-Boot:

description date status
Board Support 2012-10-29 mainline
Bootmenu Support 2013-03-07 mainline

Now all N900 patches are in upstream U-Boot mainline project (part of U-Boot 2013.04). Source code is on http://git.denx.de/?p=u-boot.git

Debian packaging for Maemo is in this git repository: https://gitorious.org/u-boot-shr/u-boot (branch maemo).

There's also a thread on talk.maemo.org, where the latest released & tested version can be found: http://talk.maemo.org/showthread.php?t=81613

More info about U-Boot on N900 is in first post.


There is an open source flasher application called 0xFFFF, which is working with the Nokia N900.

Wireshark Plugin for PhoNet


  • Uses SUPL (Secure User Plane Location) protocol (see documentation at open mobile alliance)

A-GPS works by Modem requesting CPU to open a socket (it supplies domain/ip and port) [pkg type LS_SOCKET_OPEN_REQUEST_NTF]. Then the modem will continue by requesting to send some data using pkg type LS_SOCKET_SEND_REQUEST_NTF, followed by requesting to receive some data [pkg type LS_SOCKET_RECV_REQ]. Last but not least it will request to close the socket using LS_SOCKET_CLOSE_REQUEST_NTF. The wireshark plugin mentioned above can also be used to analyse A-GPS sessions (e.g. initialized by Maemo).