Panda How to kernel 3 4 rel
Introduction
Kernel 3.4 has been released
You can download a tarball of the mainline kernel at http://kernel.org/
or you can clone a copy of mainline kernel with:
git clone http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git cd linux git checkout v3.4
Important Note
There has been a lot of work done on the HDMI interface and its related driver omapdrm. Between kernel 3.1 and 3.2-rc1 enough changed so that the Testing section on the HDMI interface is no longer correct. The hdmi init functions are no longer in arch/arm/mach_omap2/board-omap4panda.c. When this situation stabilises, the HDMI testing section below will be updated.
The entire 3.4-rcx series was plagued with problems which were only resolved in the final days of the cycle, that's why there were no How-To's on building the intermediate -rcx series. Kernel 3.4 works, although there is considerable work going on in the HDMI/DVI/DSS area as well a sound and power management.
PandaBoard ES
There is now a PandaBoard ES http://pandaboard.org/content/pandaboard-es which includes an OMAP 4460 at up to 1.2GHz. Several important differences make it important (at the present time) that the MLO/u-boot be specifically crafted for the 4460. The thermal management is not in the mainline 4430 code as yet and therefore the max clock frequency when running the OMAP4460 on the PandaBoard ES with the mainline kernel is 920MHz(same as the OMAP4430).
wlan12xx
wlan12xx patch
This patch is still necessary to resolve the issue noted in 3.0, 3.1 and 3.2, the code was moved to twl_common.c.
0001a-omap4-pandaboard-wlan-fix.patch
Apply it like so: (from inside the kernel sources directory)
patch -p1 < 0001a-omap4-pandaboard-wlan-fix.patch
The latest wlan firmware is available from git: git://git.kernel.org/pub/scm/linux/kernel/git/dwmw2/linux-firmware.git just copy the contents of the ti-connectivity folder to /lib/firmware/ti-connectivity.
The patch is no longer necessary for the PandaBoard ES but does not seem to hurt if applied. In addition, the race issue that required building as a module has returned. As part of the code cleanup, the wl12xx and wl12xx_sdio drivers no longer depend on each other. This creates an issue with systems that do not use udev or mdev (with as somewhat fiddly & slow script) to load MODALIAS drivers. The quick solution is to modprobe both, the order no longer matters. Just modprobing wl12xx_sdio will no longer automatically load wl12xx. It is suggested that these 2 drivers be built as modules.
Building
Building 3.3 is fairly straight forward.
Grab the 3.3 sources and use config.3.3.1 as the .config
The 3.3 .config enables Sound builtin and wl12xx as modules. The builtin sound does not presently work, but the enabled configuration allows USB sound devices, which function properly.
Then compile like so:
make ARCH=arm CROSS_COMPILE=Path_to_your/arm-2010q1/bin/arm-none-linux-gnueabi- uImage
Testing
fbtest on DVI Port
After booting run fbtest to see a nice test pattern from the dvi port.
Switching primary display to the HDMI port --> Currently not functional <--
Make sure that a monitor is plugged into the HDMI port before doing the following:
# Enable HDMI echo "1" > /sys/devices/platform/omapdss/display1/enabled # Disable overlay0 (an overlay must be disabled before changing its properties) echo "0" > /sys/devices/platform/omapdss/overlay0/enabled # Set the manager of overlay0 to display1 which is HDMI echo "tv" > /sys/devices/platform/omapdss/overlay0/manager # Enable overlay0 echo "1" > /sys/devices/platform/omapdss/overlay0/enabled
And content on overlay 0 of primary lcd would be transferred to HDMI. It works similarly for all other overlay's.
Switching primary display to the DVI port
See: http://omappedia.org/wiki/Bootargs_for_enabling_display for lots of useful info on the display subsystem. Be aware that the display, manager and overlay numbers don't match the panda configuration.
Make sure that a monitor is plugged into the DVI port before doing the following:
# Disable HDMI echo "0" > /sys/devices/platform/omapdss/display1/enabled # Disable overlay0 (an overlay must be disabled before changing its properties) echo "0" > /sys/devices/platform/omapdss/overlay0/enabled # Set the manager of overlay0 to display0 which is DVI echo "lcd2" > /sys/devices/platform/omapdss/overlay0/manager # Enable overlay0 echo "1" > /sys/devices/platform/omapdss/overlay0/enabled
The above commands should be run from the serial console and the cable should be in the destination port before running the commands.
fbtest on HDMI Port --> Currently not functional <--
Run fbtest to see a nice test pattern from the HDMI port.
i2cdetect
You can run i2cdetect and the results should look like this:
# i2cdetect -y -r 1 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- UU UU UU UU -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- --
wlan
Run the following commands after the PandaBoard is booted:
modprobe wl12xx ** only if you built the wl12xx drivers as modules modprobe wl12xx_sdio ** only if you built the wl12xx drivers as module ifconfig wlan0 up iwconfig wlan0 essid "Your AccessPoint Name" udhcpc -i wlan0
If your network is set up to provide DHCP services, the PandaBoard will get all the "right stuff(tm)" and you will be able to access the Internet.
# ping www.google.com PING www.google.com (74.125.73.99): 56 data bytes 64 bytes from 74.125.73.99: seq=0 ttl=43 time=62.683 ms 64 bytes from 74.125.73.99: seq=1 ttl=43 time=54.077 ms 64 bytes from 74.125.73.99: seq=2 ttl=43 time=51.484 ms 64 bytes from 74.125.73.99: seq=3 ttl=43 time=54.108 ms
USB Performance
Insert a USB memory stick into one of the usb ports
Run dmesg to see what sdx the stick was recognised as, then:
hdparam -tT /dev/sdx
If you run the same command on a desktop Linux system, with the same USB memory stick, the PandaBoard's speed should roughly be the same.