Building FreeBSD’s SDIO driver for BeagleBone Black

Hi all, This post mainly concern with building FreeBSD’s SDIO driver for BeagleBone Black by cross compiling it on AMD platform. I had few unresolved issues with the master branch of current FreeBSD tree. So, for this i used another unofficial branch: https://github.com/kibab/freebsd/tree/mmcam-new . It does have the required KERNCONF file with stable SDIO driver.

A lot of steps below are similar to the one given on: https://forums.freebsd.org/threads/cross-compiling-beaglebone-on-amd64.64718/#post-384835  with slight but inevitable changes.

Procedure:

1.  Before proceeding you need to first install git.

   sudo pkg update -f
   sudo pkg install git

2.  Setup project directory by mkdir /BBB
3.  Clone the repository to /BBB/src by

   git clone -b mmcam-new https://github.com/kibab/freebsd.git /BBB/src

4. Setup environment variables as

   setenv BASEDIR /BBB
   setenv MAKEOBJDIRPREFIX $BASEDIR/obj
   setenv TARGET arm
   setenv TARGET_ARCH armv6

   Note that sometime it shows an error like: Undefined command setenv, in that case just switch to root as sudo -E su and then try setting the environment variables again.

5. Create image file and setup MSDOS filesystem for u-boot

   truncate -s 2048M /BBB/bbb.img
   mdconfig -f /BBB/bbb.img -u md0
   gpart create -s MBR md0
   gpart add -t \!12 -s 10m md0
   newfs_msdos -F12 -L 'MSDOSBOOT' /dev/md0s1
   gpart set -a active -i 1 md0

6. Make Buildworld and buildkernel

   cd $BASEDIR/src
   make -j8 buildworld TARGET=arm TARGET_ARCH=armv6 UBLDR_LOADADDR=0x88000000 -DWITH_FDT __MAKE_CONF=/dev/null SRCCONF=/dev/null
   make buildkernel TARGET_ARCH=armv6 KERNCONF=BEAGLEBONE-MMCCAM

   Note here, that if your FreeBSD AMD environment is on virtual box, for above builds to be successful you need around 2Gb of RAM and 4Gb of Swap memory with -j7 option. Swap space can be checked via swapinfo command. For adding more swap just head towards: https://www.freebsd.org/doc/handbook/adding-swap-space.html

7. Mount the MSDOS partition and copy the uboot stuff to it.

   mount_msdosfs /dev/md0s1 /mnt
   cp /usr/ports/sysutils/u-boot-beaglebone/work/u-boot-2018.03/MLO /mnt
   cp /usr/ports/sysutils/u-boot-beaglebone/work/u-boot-2018.03/boot.scr /mnt
   cp /usr/ports/sysutils/u-boot-beaglebone/work/u-boot-2018.03/u-boot.img /mnt
   cp /BBB/obj/arm.armv6/BBB/src/sys/boot/arm/uboot/ubldr /mnt
   cp /BBB/obj/arm.armv6/BBB/src/sys/boot/arm/uboot/ubldr.bin /mnt
   umount /mnt

   Note that sysutils/u-boot-beaglebone port doesn’t come by default, in fresh FreeBSD installation. It has to be installed by

   pkg install u-boot-beaglebone
   cd /usr/ports/sysutils/u-boot-beaglebone/ && make install clean

8. Make the freebsd-ufs partition

   mkdir /mnt1
   gpart add -t freebsd md0
   gpart create -s BSD md0s2
   gpart add -t freebsd-ufs md0s2
   newfs /dev/md0s2a
   tunefs -N enable -j enable -t enable /dev/md0s2a
   mount /dev/md0s2a /mnt1

9.  Do installworld, installkernel into the partition

   make installworld TARGET_ARCH=armv6 DESTDIR=/mnt1
   make distribution TARGET_ARCH=armv6 DESTDIR=/mnt1
   make installkernel TARGET_ARCH=armv6 KERNCONF=BEAGLEBONE-MMCCAM DESTDIR=/mnt1

10.  Install setup, create fstab and rc.conf

    touch /mnt1/firstboot
    mkdir /mnt1/boot/msdos
    
    ee /mnt1/etc/fstab
    # Custom /etc/fstab for FreeBSD embedded images
    /dev/sdda0s1    /boot/msdos    msdosfs rw,noatime    0 0
    /dev/sdda0s2a    /        ufs rw,noatime        1 1
    
    ee /mnt1/etc/rc.conf
    hostname="beaglebone"
    ifconfig_DEFAULT="DHCP"
    sshd_enable="YES"
    sendmail_enable="NONE"
    sendmail_submit_enable="NO"
    sendmail_outbound_enable="NO"
    sendmail_msp_queue_enable="NO"

11. Complete setup by

    umount /mnt1
    mdconfig -d -u0

     

Great, you are now ready to go and dd the obtained bbb.img image to sd card. With every thing working kernel should boot up with multiple MMCCAM debug logs as in here. In case of any error, feel free to post it on the forums or comment below.

UPDATE(24/06/18):

SDIO driver has now been fixed in FreeBSD-Current head. In order to build for FreeBSD-Current just use GENERIC-MMCCAM kernel config file instead of BEAGLEBONE-MMCCAM.

References:

• https://forums.freebsd.org/threads/cross-compiling-beaglebone-on-amd64.64718/#post-384835
• http://freebsd-arm.freebsd.narkive.com/dZ0TaVwR/bbb-imx6-hummingboard-sdio-driver#post14
• https://wiki.freebsd.org/SDIO