Are you bored off that crappy closed-source fglrx (AMD’s official linux driver)? Or you just can’t stand having Unidentified Flying Object in your RAM? If you own an R6xx/R7xx gpu based card then good news for you, there is finally 3d support for you! Not finished yet but at very good stage.

Let’s try to explain something before we start, there is one “new” technology that this new driver is based on, the KMS.

Mode-setting

Is setting up the screen resolution and depth mode for the graphics card. Modern mode setting software support multiple monitors (“multi-head”) and hot plugging. In linux there are two ways to do it the old one User Mode Setting (UMS) and Kernel Mode Setting.

UMS is the old one and it was done by the X-server driver at the start of X session. For this to work, the X server needed to run as root so that it could access the resources of graphics card. Further-more switching to console involved freeing resources from graphics card and giving gpu back to the kernel. Switching back to X session from console, the driver had to reinitialize hardware from the scratch and lock it again.

KMS is the new one and the mode-setting is done by the kernel its self without the need of X server. Kernel modules has been written for some cards and are being developped for the rest, that are capable of controlling gpu mode-setting in-kernel. X server driver does not need to access GPU in low-level anymore but requests mode changes from the kernel’s KMS API which sends commands to GPU. Advantages are numerous, like switching to console and back does not involve releasing/locking card and reinitializing it each time. Kernel can detect monitors and console is run at the screens optimal resolution (no more 640×480 console). Also x server drivers does not need any more to run under “root” to access gpu, (this has been accomplished with changes in others areas of X-server stack too). To work in KMS mode you need the appropriate modules in kernel that will implement KMS for your GPU, and the new X server driver that will access graphics card through KMS and not directly.

There are more stuff involved in the new X server stack like DRM/DRI2, vga_switcheroo (vga switching). There are plenty of information out-there to read.

Latest R600/R700 stack on Karmic 9.10

WARNING: You will run experimental software, that may have serious bugs and make your system unstable. To perform the following steps you must be familiar with linux terminal and deb packages. If you don’t know what are these, don’t even try it. In any way the process may result in broken X session.

You want open-source radeon driver with 3D, compiz, KMS support right now? You have to update to the latest unreleased code of drm-next source tree (yes you have to pull 2.6.34 DRM code for proper support), and to the latest MESA-DRI-Xorg radeon driver.

Get latest kernel with drm-next tree from the kernel mainline

Visit http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-next/current/ and download 3 files on folder that you will create on the Desktop named drmnext

linux-headers-[VERSION]_all.deb
linux-headers-[VERSION]_{ARCH}.deb
linux-image-[VERSION]_{ARCH}.deb

For example for my i386 I downloaded the following files:

linux-headers-2.6.33-996_2.6.33-996.201003011149_all.deb
linux-headers-2.6.33-996-generic_2.6.33-996.201003011149_i386.deb
linux-image-2.6.33-996-generic_2.6.33-996.201003011149_i386.deb

Then open-terminal and CD to the folder where you downloaded them, and install them

cd ~/Desktop/drmnext
sudo dpkg -i linux-*2.6.33*.deb

Kernel misses some firmware files R600_rlc.bin and R700_rlc.bin that you have to download manually and install them in your linux installation.

sudo wget -O /lib/firmware/2.6.33-996-generic/radeon/R600_rlc.bin http://people.freedesktop.org/~agd5f/radeon_ucode/R600_rlc.bin
sudo wget -O /lib/firmware/2.6.33-996-generic/radeon/R700_rlc.bin http://people.freedesktop.org/~agd5f/radeon_ucode/R700_rlc.bin

You have to update initramfs because this firmware is needed early at kernel load. You will also need to enable the experimental “power management” code of the module otherwise your GPU will work at full speed even when idle, resulting in heat and fan working continuously.

sudo bash -c "echo \"options radeon dynpm=1\" > /etc/modprobe.d/radeon.conf" 
sudo update-initramfs -u -k 2.6.33-996-generic

Now you have to update your xorg stack to the latest. This can be done easily using xorg-edgers ppa.

sudo add-apt-repository ppa:xorg-edgers/ppa
sudo apt-get update
sudo apt-get upgrade

Ok you are ready! Cross your fingers and reboot, select kernel 2.6.33 on grub and good luck

F*$% that crap! I want to go back

If you are not a satisfied client then you can always return back to default ubuntu packages with the following commands

sudo apt-get install ppa-purge
sudo ppa-purge xorg-edgers

Reboot and select 2.6.31 kernel. After that you can use synaptic and remove all *2.6.33* kernels from repository, if you think that you will never need it again.

Please write back your experience or comments in comments section.

Updates

• The command to add module options missed sudo prefix, and resulted in “permission denied”. Kudos to Patric!

www.youtube.com/watch?v=VjfaCoA2sQk

I think many coders out there will agree that this is definitely a good way!

A frayed cable is not a rare case for Apple’s MagSafe power supplier, and I am proud to be part of this statistical failure. After a quick search I found out that the cable that connects the MagSafe and MacBook is prone to fraying in both ends, near magsafe and near magnetic socket. There are many users complaining for the quality of this product even in Apple’s store.

www.youtube.com/watch?v=nbUxBI8-flY

Apple has acknowledged that some of the power adapters that came with MacBooks and MacBook Pros have a flaw making them fray at the base of the plug.

My frayed cable

For me plugging power to MacBook and finding out that it didn’t charge it, was an uncomfortable situation that had to be solved. At first I went to buy a new MagSafe but 80 euros seemed too much for a frayed cable. So I decided to give it a try and fix it.

You can do this!

With a close look at MagSafe, you get to understand that it will not be easy to open it. The MagSafe has no screw or clips rather than it consists of two plastic plates that are stuck with epoxy glue. To open it you have to “break” it. Depending on how much gentle you are, the breakage will or not have aesthetic impact on the final result.

DISCLAIMER: I have no photos from the separation process as I didn’t thought to blog it until I heard the cracking sound.

You will probably only need one or two screwdrivers with a thin head. The idea is to use screwdrivers to crack the glue between the two plastic covers. You can do this by putting the screwdriver head in the indenture of the MagSafe and use it as a lever to force the edge of one cover away from the others cover edge. The best is to start from the place where the power cable clips in.

Crack the glue of external cover with a skrewdriver

This process demands a lot of patient otherwise if you press it too much you will injure the external surface. If you are patient and gentle enough you will unstick covers with minimal deformation.

MagOnion

MagSafe consists of multiple layers, you start by cracking the outer plastic cover and unfolding two protection shields till you see the actual circuit.

MagSafe's plastic cover opened in 2 piecies

The magnetic shield is 3 or 4 metal leaves that are taped with an electrical conductive tape of bronze colour. One of this leaves is short circuited with the main board of the adapter. You have to unsolder this leaf from the board before you unfold it. You also have to unscrew it from the chassis.  Finally you can untape one edge of the shield so that the shield can be removed completely from the circuit.

Internal magnetic protection of circuit

There is also a plastic shield that is short-circuit protector. This shield is glued on the circuit using silicon. You can cut the silicon with a knife or use extra force but take care not to destroy the circuit.

Electrical short-circuit protection

Here you are! Naked!

The actual circuit of MagSafe

The constructive part

After the complete demolition you are ready to rebuild. At first you unsolder the cable from the board.

The edge of the cable that was solder on the board of MagSafe

Then use any of your preferred tool to cut the damaged cable.

The edge of the cable cut out

With a blade strip the cable and separate the outer and inner cables.

Cable prepared to re-solder it on the board

Although we could just solder the cable back on the board, it would not be mechanically supported and with minimal force, the cable could be cut off of the board. To prevent this damage I have to reuse the supporting plastic but first we have to trim it a bit. Using a blade you cut it in half.

Split the supporting plastic so that can be cleaned and reused

Using any tool you believe it best fits, extract the black plastic part from the hole of the supporting plastic.

Ready for use!

Fit the cable again inside the supporting plastic

You can now use the soldering tool to resolder cable back in the board.

The MagSafe with replaced cable

At this point the electric circuit should be working again.

Reassemble it!

You need to reassemble it so that it looks like a MagSafe (or something like that). You need to rebuild all the parts that you previously removed. Starting with the plastic protection.

Apply short circuit protection on board again

After managing the plastic protection you should put back the metal protection. This will not be that easy as the plastic one. At first you can place back all leaves together and with a tape make it steady. You must use soldering tool to resolder protection on the board, as it was in the first place. And don’t forget the two screws.

Magnetic shield refited on MagSafe

We need to add a mechanical “stop” on the cable so that if someone tries to pull it jerkily, it will not unsolder from the board. I used two tire-ups which I placed them between the supporting plastic and the board.

Tire-ups protecting from pulling the cable off the board

Trim tire-ups so that they are able to fit inside the case of MagSafe.

Tire-ups trimmed to fit inside the case

You can now put the circuit back in the plastic cover,though you will probably have to push a bit the cable supporter to place it back in its proper place on the external cover. Before reasempling the external parts you can use a sewage to fix possible deformation of the edges caused at cracking process.

Board placed back in the cover

Finally you can also use epoxy glue to glue the two external parts together. You can also use duct tape for extra protection of the crack.

You made it!

It was not trivial but hey you have a working MagSafe again at no extra cost!

MagSafe GT V16 Turbo!

And here it is my MacBook and MagSafe working again!

Maybe a bit open-source enthusiast

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