Making some progress here!
I added a compiled version of the attached device tree and now the mmc1 shows up in my yocto image! Yes! Now I need to find out the secret magic in that tree that I need to add...
Chuck
Raj,
I found out how to debug the boot process of the PI from:
https://github.com/raspberrypi/documentation/blob/master/hardware/raspberrypi/bootmodes/README.md
by turning on the boot code debug.
sed -i -e "s/BOOT_UART=0/BOOT_UART=1/" bootcode.bin
I found out that the sdio overlay does not exist!
MESS:00:00:07.868162:0: dtdebug: Failed to open overlay file 'overlays/sdio.dtbo'
MESS:00:00:07.874093:0: Failed to load overlay 'sdio'
MESS:00:00:07.878881:0: brfs: File read: /mfs/sd/overlays/sdio.dtbo
MESS:00:00:07.891322:0: brfs: File read: /mfs/sd/cmdline.txt
So what am I missing on how to turn on the sdio on GPIO22-27? Is it not an overlay and instead a driver/other code/linux config that needs to be set?
Chuck
On 11/17/20 4:29 PM, chuck kamas via lists.yoctoproject.org wrote:
Raj,
Thanks for taking the time to respond. I thought of that too. My custom Yocto build has the line to turn on the sdio in it:
dtoverlay=sdio,poll_once=off
I have attached the entire file: config.txt.yocto
However, the Rasbian image does not have any mention of the dtoverlay for the sdio. Curious. See config.txt attached.
Thanks for the help!
Chuck
On 11/17/20 12:08 AM, Khem Raj wrote:
On Mon, Nov 16, 2020 at 11:43 PM chuck kamas via
lists.yoctoproject.org <chuckkamas=yahoo.com@lists.yoctoproject.org>
wrote:
Hi all,what does /boot/config.txt look like on raspbian and yocto built images
I have been spinning my wheels for two days trying to discover how to
enable MMC1 on a CM3. This is the one on GPIO22-27. I can boot Rasbian
on the CM3 and it inits the MMC1 and its pins just fine. I can
read/write to my SD card from it etc. However, when I build yocto it
leaves the GPIOS22-27 in gpio mode and does not set them to MMC1 mode.
I have tried changing the device tree as described here:
https://stackoverflow.com/questions/44702426/how-to-setup-an-own-device-tree-for-a-raspberrypi-in-yocto
That compiles and add the .dtbo to my build, but still the GPIOS are not
set to MMC1 mode.
cat /sys/kernel/debug/pinctrl/*gpio*/pinmux-pinsI have looked at:
Pinmux settings per pin
Format: pin (name): mux_owner gpio_owner hog?
....
pin 22 (gpio22): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 23 (gpio23): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 24 (gpio24): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 25 (gpio25): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 26 (gpio26): (MUX UNCLAIMED) (GPIO UNCLAIMED)
pin 27 (gpio27): (MUX UNCLAIMED) (GPIO UNCLAIMED)
.....
https://ralimtek.com/raspberry%20pi/electronics/software/raspberry_pi_secondary_sd_card/
Any ideas of where to look next to turn on the sdio would be appreciated!
Chuck