I am working on the olimex sam9_l9260 board. I am connect kingston new mmc card in board then trying mmc info command. but i show,
U-Boot> mmc info
Card did not respond to voltage select!
how to solve this problem.
After inserting a card on boot-up (or removing and inserting a different card) you first need to use mmc rescan to cause the system to check if there is a card present currently and do some other backend work.
Related
In a DART-6UL linux based board, when I booted my system (both from eMMC or SD Card) with USB flash drive or a FTDI USB-to-serial converter inserted, it compared in: /run/media device list or in: /dev list.
When I removed it, USB devices are correctly removed, but it's no possible to inserted again. The only way is to reboot the system with USB inserted.
I tried the same on the EvKit and USB can be inserted and removed all times with no problem, without the need of reboot.
In Kernel usin Menuconfig I set CONFIG_USB_SERIAL=y and ftdi-sio module appears as regularly loaded at boot.
What can I check on my system?
I have to write a driver for a custom chip, to interface it with an SD card using SD protocol, which will have filesystems on it.
Now the obvious answer is that, since its an SD card(a block device), I will have to go with Block device driver development.
One of the answers from a previous question suggest that
"
Platform devices are inherently not discoverable, i.e. the hardware
cannot say "Hey! I'm present!" to the software.
By reading from the SD card internal registers, I can make the SD card identify itself, so does that mean SD card cannot be treated as a Platform device?
However, since we are having our own bus for connecting this SD card host controller to the CPU, would I have to write a platform driver instead of a block one?
I am new to Linux device drivers, help me out here so I can get this thing done right!
I have my raspberry pi zero, and during development I spend a lot of time to eject-inject SD card and re-flash it. SD card image is prepared in Buildroot, so it includes boot partition with kernel, device tree overlays and partition with rootfs.
Is there simpler way to re-flash SD card? For example via network? I know that U-boot can load kernel via tftp, but if I need not only kernel, but whole image(device tree overlays are extremely important)?
Use TFTP to load the kernel image, and NFS to mount the root filesystem over the network.
I accidently modified uEnv.txt file located in eMMC of my Beaglebone black. Now the board is not booting. I can not even see BBB for serial connection from terra term. How can I get access to the board? If I can just access to uboot I could reflash or run it using nfs. Any ideas?
You can boot via normal microSD card as described here:
burn a bootable image on your microSD card
insert this card
power up your BBB while holding USER/BOOT button
once in Linux - repair your uEnv.txt on eMMC
I am running an embedded Linux device and am I having trouble with file system corruptions during power off. We are talking about a normal Linux shutdown. It is one specific card I am having trouble with and it is only sometimes. I am trying to debug the Linux mmc device drives. Do anyone know what commands that should be send to the card when shutting down?
Maybe it is something like CMD15?
CMD15 does not seem to be used.