SD Card Problem - can anyone explain the reason why ?

Hi Steve,

I think I have the same problem as you.

I have a 32GB SD-Card by SanDisk, but at startup my PI says:

mmc0: Timeout waiting for hardware.

Not once - seems like 3 or 4 screens full on a 1920x1080 screen.

Thats odd, and it even seems not to respond when I want to login.

I will try some more but I think I will have it replaced.

Thanks

Tim

You need to either recompile your kernel,or apply the updates (firmware repo) from: raspberrypi · GitHub

Easy method: download the firmware repo and copy the the contents of the boot directory to the boot partition of your SDcard.

Compilation details on cross compiling a kernel (linux repo) can be found here: http://elinux.org/Rpi_kernel_compilation

the running current .config file (needed to compile working kernel) can be found on a running raspberry pi in /proc/config.gz

Worked for me... There is a known bug in the current SDHI driver which has been resolved in the nightly/weekly build in the repository mentioned above.

John

Many people are experiencing X and lxde (the window manager) problems.

Please read http://www.raspberrypi.org/phpBB3/viewtopic.php?f=2&t=5169&p=69379 & http://www.raspberrypi.org/phpBB3/viewtopic.php?f=26&t=5851 for a possible solution.

John

@John,

Does this answer all problems for the SD cards ? There is quite a list here: http://elinux.org/RPi_VerifiedPeripherals#Problem_SD_Cards

@Tim: A lot of Sandisk cards on the list.

To be honest, I can't understand why there is such a problem with cards, they seem to work fine with *every* other piece of equipment I have used them in.

Steve,

  According to page 65 of

https://www.element14.com/community/docs/DOC-43016

the SD card interface is provided by Arasan, and compliant with

• SD Host Controller Standard Specification Version 3.0 Draft 1.0

• SDIO card specification version 3.0

• SD Memory Card Specification Draft version 3.0

• SD Memory Card Security Specification version 1.01

• MMC Specification version 3.31,4.2 and 4.4

I don't know if other Arasan SD card controllers have similar issues.

The Roku 2 uses microSD, but the same SoC, and they apparently

have a working system.

In my limited understanding of this post

http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=7665

it appears the R-Pi is doing some odd things with the SD Card interface (like treating clock speed as if every card is a MMC card, instead of using the recommended SD card clocks)

In my *extremely* limited understanding of that post, it looks like it is trying to do something it shouldn't be trying to do ?

Like I say above, I have lots of equipment that takes SD cards and they all just work - surely the SD specifications are well enough known and worked to now that to try something outside of those specs isn't a good idea ?

For anyone who hasn't been following over on the 'other' forums, there's a newer kernel + firmware available that has proved to have much better results with all manner of SD cards. It achieves much better performance - up to 5x on simple sequential read tests, due to configuring the cards and the interface properly.  It's very much worth trying. Especially if you had problems before.

Note that you really must update both kernel and firmware at the same time as there's a dependency on what clock speed the firmware sets vs what the kernel expects.