Nokia N900

Nokia N900
Manufacturer	Nokia
Codename	Rover, RX-51
Dimensions	110.9mm x 59.8mm x 18mm
Release Date	2009-11-11
Category	Supported
Specifications
SoC	TI OMAP 3430 @600MHz ; overclock @850MHz ; Cortex-A8 ; Armv7‑A
DRAM	256 MB Mobile DDR
Hardware Features
LCD	800x480 3.5" Resistive TFT
Video	PowerVR SGX530
Network	WL1251
Storage	32GB
USB (Host/OTG)	Micro USB 2.0 Slave
Battery Capacity	1320mAh
Software Features
Kernel	6.1
Serial	Yes, UART under battery, 2.7V max!
Charging	Yes
USB Slave	Gadgets only
USB Host	With hacks
Touchscreen	Yes, single-touch
Keyboard	Yes
Screen	Yes
TV-out	Yes
3D acceleration	Yes, closed driver
Vibration motor	Yes
Audio	Yes (complex, ucm, no speaker protection)
Phone calls	Yes/WIP
SMS	Yes
Wifi	Yes, firmware required
IrDA	Yes, actually CIR, not IrDA
2G/3G data	Yes
Bluetooth	No
FM transmitter	Yes
FM receiver	No
Accelerometer	Yes
Proximity Sensor	Yes
Ambient Light Sensor	Yes
GPS	Yes
A-GPS	No
Idle Power Consumption	160mW (WIP)

Installation

The installation consists of two steps: copying the image to the microsd card, and setting up the bootloader on the phone.

Image installation

Latest image: https://phoenix.maemo.org/job/leste-image-n900/lastSuccessfulBuild/artifact/arm-sdk/dist/
Image archive: https://maedevu.maemo.org/images/n900/

dd the image to an sd card.

If using a Windows machine, you can use Etcher

See the next section on how to boot. (using either 0xFFFF/flasher-3.5 or u-boot/bootmenu: http://talk.maemo.org/showthread.php?t=81613)

Bootloader (U-Boot) setup

Quick

If you don't want to configure u-boot from Fremantle, or your Fremantle rootfs is broken), or you just want to install quickly:

1. Either download 0xFFFF (binary for x86) from https://maedevu.maemo.org/images/n900/tools/ or build from source from https://github.com/pali/0xFFFF/

2. Download u-boot from https://maedevu.maemo.org/images/n900/tools/

3. Turn off Nokia N900, issue the following command on PC and connect Nokia N900 to the PC: sudo ./0xFFFF -m test/u-boot-2013.04-2.bin -l

4. Open the keyboard slider on the N900, and then issue following command on PC to test boot: ./0xFFFF -b

This should present u-boot from which you can select external SD card and boot to Maemo Leste. If you are presented with a menu, select the option to boot from External SD card. If you just get a command prompt, type run sdboot.

To flash u-boot permanently, you can issue the following command

(Be careful though. This will replace the existing fremantle kernel. Only do this if you do not care about the existing maemo installation or you know how to recover from this condition))

sudo ./0xFFFF -m test/u-boot-2013.04-2.bin -f

Existing Fremantle

If you have a functional Fremantle installation, you can follow these steps instead:

1. Install "U-Boot with kernel 2.6.28-omap1"

2. Install "Linux kernel for power user (boot image for U-Boot)". This is optional, but recommended.

3. Add Maemo Leste menu item (run as root):

cat > /etc/bootmenu.d/30-maemo-leste.item << "EOF" &&
ITEM_NAME="Maemo Leste"
ITEM_KERNEL="uImage"
ITEM_DEVICE="${EXT_CARD}p1"
ITEM_FSTYPE="ext2"
EOF
u-boot-update-bootmenu

4. Reboot the device with the keyboard slide open (U-boot will boot the default option if the keyboard slide is closed)

Increase filesystem size

Run the following script: /etc/expandcard.sh

Serial

http://n900.elektranox.org/serial-adapter.html

http://wiki.maemo.org/N900_Hardware_Hacking#Debug_ports

Use this command line (specifically the part after rootwait):

root=/dev/mmcblk0p2 rootwait console=ttyS2,115200 verbose earlyprintk debug

Notes

Speakers

Speakers are enabled by default, but be careful of very high frequencies/levels - there are concerns regarding the possibility to blow them. There is no clear consensus about this, but it is best to err on the side of caution.

Torch

The N900 has an Analog Devices ADP1653 flash controller, mainly for use with the camera. It drives two white power LEDs connected in series, and has an additional red indicator led (referred to as a privacy indicator). The ADP1653 has a driver in mainline kernel, and it probes fine. However, some DTS changes are needed to make it work, since the driver requires it to be tied to a camera.

In the meantime, the LEDs can be used as a torch manually using i2cset. However, BE WARNED: setting wrong values via i2c runs the risk of over-driving the LEDs and causing permanent hardware damage.

Install the prerequisites
$ sudo apk add i2c-tools

Unload the driver in case it is already loaded. We will use i2c manually
$ sudo modprobe -r adp1653

Enable the chip
$ echo 88 | sudo tee /sys/class/gpio/export
$ echo "out" | sudo tee /sys/class/gpio/gpio88/direction
$ echo 1 | sudo tee /sys/class/gpio/gpio88/value

Turn the torch on, using the lowest torch current - DO NOT use other values here or you risk burning the LED
Values between 1 and 7 enable the red privacy/recording led, with different intensity
0x8 is the lowest torch intensity, and we do not recommend going above it
$ sudo i2cset -y 2 0x30 0x0 0x8

Turn the torch off
$ sudo i2cset -y 2 0x30 0x0 0x0

Disable the chip
$ echo 0 | sudo tee /sys/class/gpio/gpio88/value
$ echo 88 | sudo tee /sys/class/gpio/unexport

Power Management

This ticket tracks hitting idle states for the N900: https://github.com/maemo-leste/bugtracker/issues/545

Power usage right now is reported to be about 45mA (idle, modem ON and data ON). On a good battery this will last for about 30 hours. Power management on the N900 is being worked on: https://github.com/maemo-leste/bugtracker/issues/170

Run:

modprobe ledtrig-default-on

And:

echo default-on > /sys/class/leds/debug::sleep/trigger

To enable the OMAP sleep debug LEDs (on the keyboard). Open keyboard, turn off the screen with the slider, and the LEDs will turn off if the phone ever reaches sleep modes.

Currently it does not yet reliably reach any sleep modes.

See this code for a work in progress power management script: https://github.com/maemo-leste/n900-pm

Battery calibration

Nokia N900 has bq27200 integrated circuit for monitoring battery state. The datasheet can be found here: http://www.ti.com/lit/ds/symlink/bq27200.pdf. If you are curious, check the section called "Gas Gauge Operation" for how the battery calibration is done in a low level.

Here are described the steps necessary to calibrate your battery. This should help if you see "Battery not calibrated" message in the status applet.

Fully charge Nokia N900. Don't detach the charger immediately, give it some time after you see "Fully charged" message (10 minutes should be enough).
Detach the charger and don't attach it again until the battery is fully depleted. Remember: if you attach the charger (or USB cable) at least once, you will need to start the calibration from the beginning (fully charge the device again).
You may use the device as you normally do. You may power it off, power it on, reboot. All as usual. Just don't connect the device to a charger or a PC using the USB cable.
When your Nokia N900 has battery depleted, it will alarm you with the "battery low" sound.
Wait for about 20 seconds and attach the charger. If the device was powered off because of battery depletion, it's fine. The battery should have done the calibration cycle. Just attach the charger to the device, give it a minute and press power button to start booting.
If you still see "Battery not calibrated" message, reboot the device.

After the first calibration cycle you will see that it has ~1700 mAh for the fully charged battery. This value is wrong. It's how the battery calibration works in low level: it can't change the fully charged value of the battery in steps that exceed 12.5%. What this means for us: it's needed to repeat the calibration cycle several times to get more accurate value. It may take about 3-7 calibration cycles to get the proper mAh value for fully charged battery. If you spend some time on this process, you will get really accurate battery gauge and you will always know how much charge is remaining.

Tip 1. If for any reason you want to reset the battery calibration value to see the message “Battery is not calibrated” again, you should remove the battery from the device for about 6 hours. Tip 2. If you replace the battery, you may want to do 1-2 calibration cycles described above to update the gauge for your new battery.

Accessing MTD

List devices:

cat /proc/mtd

Mount:

apt install mtd-utils
mkdir -vp /mnt/fremantle
ubiattach -p /dev/mtd5
mount -t ubifs ubi:rootfs /mnt/fremantle

Overclocking

Nokia N900 with Leste is stable using following scalable frequencies and is much, much faster:

250-500-600-720-850MHz

To be able to overclock two steps are needed:

1) From Fremantle: add new Maemo Leste menu item (run as root):

cat > /etc/bootmenu.d/30-maemo-leste-Overclock.item << "EOF" &&
ITEM_NAME="Maemo Leste Overclock"
ITEM_KERNEL="uImageX"
ITEM_DEVICE="${EXT_CARD}p1"
ITEM_FSTYPE="ext2"
EOF
u-boot-update-bootmenu

2) From Maemo Leste (run as root):

cp /usr/lib/linux-image-omap/omap3-n900.dtb /home/user

dtc -I dtb -O dts /home/user/omap3-n900.dtb -o /home/user/omap3-n900.dts

(wait for a few seconds...)

chmod +w /home/user/omap3-n900.dts

(then the funny part...)

nano /home/user/omap3-n900.dts

(Now it's time to modify frequencies and voltage: be careful to do exactly the same)

Find "opp-table" with ctl+w and Replace all content in "opp-table { opp1 opp2 opp3 opp4 opp5 opp6 };"

New opp-table:

opp-table {
		compatible = "operating-points-v2-ti-cpu";
		syscon = < 0x05 >;
		phandle = < 0x03 >;

		opp1-250000000 {
			opp-hz = < 0x00 0xee6b280 >;
			opp-microvolt = < 0xee098 0xee098 0xee098 >;
			opp-supported-hw = < 0xffffffff 0x03 >;
		};

		opp2-500000000 {
			opp-hz = < 0x00 0x1dcd6500 >;
			opp-microvolt = < 0x106738 0x106738 0x106738 >;
			opp-supported-hw = < 0xffffffff 0x03 >;
			opp-suspend;
		};

		opp3-600000000 {
			opp-hz = < 0x00 0x23c34600 >;
			opp-microvolt = < 0x124f80 0x124f80 0x124f80 >;
			opp-supported-hw = < 0xffffffff 0x03 >;
		};

		opp4-720000000 {
			opp-hz = < 0x00 0x2aea5400 >;
			opp-microvolt = < 0x124f80 0x124f80 0x124f80 >;
			opp-supported-hw = < 0xffffffff 0x03 >;
		};

		opp5-850000000 {
			opp-hz = < 0x00 0x32a9f880 >;
			opp-microvolt = < 0x149970 0x149970 0x149970 >;
			opp-supported-hw = < 0xffffffff 0x03 >;
		};
	};

Then ctl+x to save and close.

And still as root:

rm /home/user/omap3-n900.dtb

dtc -I dts -O dtb /home/user/omap3-n900.dts -o /home/user/omap3-n900.dtb

Check your kernel version:

uname -r

For example if the result is 6.1.30, your vmlinuz version is vmlinuz-6.1.30

In the next command, replace "vmlinuz-<version>" by yours (ie vmlinuz-6.1.30)

As root:

cat /boot/vmlinuz-<version> /home/user/omap3-n900.dtb > /tmp/zImage_dtb

mkimage -A arm -O linux -T kernel -C none -a 80008000 -e 80008000 -d /tmp/zImage_dtb /boot/uImageX

That's it !

Now reboot and select "Maemo Leste Overclock in bootmenu".

(WARNING: always use stock "Maemo Leste" in bootmenu before dist-upgrade / kernel update. (New uImageX must be created again and old uImageX must be removed))

Installing cpufrequtils is useful to change frequency governors.

Prefer "conservative" instead of "ondemand" governor.

"Performance" governor locks N900 at 850MHz.

As root cpufreq-set -c 0 -g conservative

(Note: overclocking will be integrated in kernel 6.6 and be available using boost mode in cpufreq out of the box)

Tips / Tweaks

SD Card and first boot

To avoid overall slowness, using SDXC U3 microsd card is a must. Class10 U1 cards are too slow to run Leste on N900 unfortunately.

First boot is a bit complicated because Leste is loading lot of things even if hildon-desktop is already visible. In every cases it is very slow but normal. (wait at least 3 min before clicking somewhere). Connecting to Wi-Fi must be avoided until the second/third boot (apt-worker starts automatically and N900 is unresponsive for 3 or 4 minutes). Don't forget to run /etc/expandcard.sh on first boot and check if swap is activated. Then reboot. WARNING: at the moment there is no way to see if Leste has been loaded entirely or not. It means that once hildon-desktop is visible, please wait 1-2 minutes before using the device (and avoid slowness).

(Note: it is recommended to dist-upgrade to -devel to enable more features)

Deactivating apt-worker

Run:

gconftool -s --type int /apps/hildon/update-notifier/check_interval 2147483647

Removing 125MHz CPU frequency (no overclock)

Replace 125000 by 250000 in

/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

More SWAP / SWAP activation

Enabling swap on eMMC 768MB partition if not already activated on first boot (works on the fly):

sudo swapon /dev/mmcblk1p3

(editing /etc/fstab/ is not needed and done automatically on next reboot)

(Note: eMMC swap is highly recommended and faster than SD card swap)

Other possibility: create a simple 1GB swap file on the SDcard if swap is missing:

sudo dd if=/dev/zero of=/swapfile bs=1024 count=1048576

(It takes some time...)

sudo chmod 600 /swapfile

sudo mkswap /swapfile

sudo swapon /swapfile

To make the change permanent open:

sudo nano /etc/fstab

And add this line:

/swapfile swap swap defaults 0 0

To check if the swap is active:

sudo swapon --show

Running Xorg at 16bpp

It is at the moment just a workaround but running Xorg using 16bpp make N900 faster and smoother.

As root:

nano /usr/share/X11/xorg.conf.d/99-omap.conf.leste

Add this line in Section "Screen":

DefaultDepth 16

Then reboot.

Warning: qml is not working at the moment at 16bpp.

Tweaking Transitions

Many options are missing in CSSU Features package but it is possible to edit them in transitions.ini.

As root

nano /usr/share/hildon-desktop/transitions.ini

See Fremantle documentation for perfect setup.

Web browsing

Links2 is currently the fastest and the most usable web browser on N900 -using an easy tweak-

sudo apt install links2

To use it in graphical mode, run in terminal:

links2 -g

or press the hildon desktop icon.

Then press Ctl + Shift + N to disable Hildon composition -links2 performances will increase a lot-

Press Ctl + Shift + N if you want to enable Hildon composition again.

Retroarch

First things to do:

Edit

/home/user/.config/retroarch/retroarch.cfg

menu_driver = "glui"

menu_show_core_updater = "true"

video_driver = "gl"

video_vsync = "true"

menu_unified_control = "true"

menu_core_enable = "true"

quick_menu_show_options = "true"

Some emulators are working well:

- QuickNES (NES/Famicom)

- Snes9x 2005 (SNES/Super Famicom)

Others at 70-80% speed:

- Genesis Plus GX (SEGA MS/GG/MD/CD)

Go to Online Updater / Core Updater to download emulators

Retroarch recommended settings:

To avoid crashes, use only "glui" Menu Driver

Driver

Input driver "X", joypad driver "linuxraw", video driver "gl", audio driver "null", location driver "null"

Video

Aspect ratio "core provided", Integer scaler "no", Threaded Video "yes", Vertical Sync "yes", Hard gpu Sync "no",

Audio

Audio Enable "no"

Input (very important)

Unified Menu Controls "yes"

Input User 1 Binds (keyboard settings)

Directory (very important)

Core "/home/user"

Default keyboard keys

X validate/ok

C cancel/back

F fullscreen (never close Retroarch in fullscreen mode)

Social messaging

Conversations app is compatible with libpurple and irc/bitlbee server.

Twitter, Signal, Telegram, FB Messenger and others are working.

(most audio and video links are playable)

Video playing

Video playing is working fine using SMPLAYER:

- In Options / Preferences / General:

Media engine: Other: /user/bin/mplayer

- In Options / Preferences / Video:

Output driver: xv

Only unable Double buffering and Disable screensaver

- In Options / Preferences / Audio:

Output driver: pulse

Disable everything else

Channel by default: 2 (Stereo)

High speed playback: No

- In Options / Preferences / Performance:

Unable Allow frame drop

Hardware decoding: None

Prefer 360p - 480p max video format

(With overclocking, Video is working well using KODI 17.6 with equivalent A/V settings)

Status table

Feature	Leste supported	Notes
Kernel version	6.1.48	Mainline + PowerVR Patches: https://github.com/maemo-leste/droid4-linux
Serial	Yes	Requires special hardware
Charging	Yes
Wireless	Yes	Firmware is non-free
Ethernet	N/A
Micro USB	Yes	USB Network, Mass Storage. OTG not working, although it might be possible
Keyboard	Yes
Screen	Yes
3D Acceleration	Yes	closed PowerVR driver
Overclock	Yes	up to 850MHz (stable), Turbo mode works
Touchscreen	Yes	Resistive
Audio	Yes	Works (minus speaker protection), UCM support with Jack plug/unplug detection
2G/3G/3.5G data	Yes	Works with ofono - UI is working, see https://github.com/maemo-leste/connui-cellular/
4G data	N/A	no hardware
SMS	Yes	Works with ofono and Sphone
Phone calls	Yes	Works well using ofono scripts, UCM support, some integration remains with Sphone, sound is good. Works in 2G, 3G and 3.5G mode, low and stable latency.
SIP calls / IM	Yes	Works with Twinkle, TLS transport is supported, Telepathy/Sphone integration is WIP
Bluetooth	No	Driver needs some work
FM Transmitter	Yes	Select 'FM Transmitter' in Pavucontrol Install `v4l-utils` and set frequency using: `v4l2-ctl -d /dev/radio0 -c mute=0,tune_power_level=120 -f <freq>`
FM Receiver	No	Depends on working Bluetooth stack
Accelerometer	Yes	Not used in Leste at the moment, since UI rotation does not work on N900
Compass	N/A	No hardware
Gyro	N/A	No hardware
Proximity sensor	Yes	evdev interface not supported in mce since it depends on iio-sensor-proxy support. https://gitlab.freedesktop.org/hadess/iio-sensor-proxy/-/issues/363 for possible 'fix'
Ambient Light Sensor	Yes
Vibration Motor	Yes
HDMI-out	N/A	No hardware
TV-out	Yes	Enable in alsamixer (Jack Function in alsamixer to TV OUT), enable with `xrandr --output TV --mode 800x480 --same-as LCD`. Set PAL/NTSC with `xrandr --output TV --set SignalProperties PAL`, and scale with `xrandr --output TV --set TVScale 90`.
GPS	Yes
Infrared	Yes	TX only (hardware limitation). Works with pwm-ir-tx driver (patched)
Camera	No	Needs complex v4l work, no leste integration
Idle power consumption	~160mW / up to 30 hours	Device does not enter RET or OFF mode