title: Raspberry 3: booting a Kernel by using U-Boot
body: <p>I am playing around with a Raspberry 3 and try to boot a Linux Kernel by using U-Boot.</p>
  
  <p>I've built a Linux Kernel (from github.com/raspberrypi), and Busbox-Userland.
  This Kernel boots and works just fine, when booting 'directly' (that means without U-Boot).</p>
  
  <p>Now I've built U-Boot (Mainline, denx.de/u-boot.git), which also seems to work.</p>
  
  <p>It boots and is accessible (both by HDMI/USB and [after adding pi3-disable-bt-Overlay]).</p>
  
  <p>But now I am stuck; the Kernel won't start from within U-Boot.</p>
  
  <p>I tried the following commands:</p>
  
  <pre><code>setenv fdtfile bcm2710-rpi-3-b.dtb
  
  mmc dev 0
  fatload mmc 0:1 ${kernel_addr_r} kernel7.img
  fatload mmc 0:1 ${fdt_addr_r} ${fdtfile}
  setenv bootargs earlyprintk console=tty0 console=ttyAMA0 root=/dev/mmcblk0p2 rootfstype=ext2 rootwait noinitrd
  bootz ${kernel_addr_r} - ${fdt_addr_r}
  </code></pre>
  
  <p>U-Boot's output is then:</p>
  
  <pre><code>[...]
  reading kernel7.img
  [...]
  Kernel image @ 0x1000000 [ 0x000000 - 0x40e630 ]
  ## Flattened Device Tree blob at 0x000100
     Booting using fdt blob at 0x000100
     Using Device Tree in place at 0000100, end 00006b1a
  
  Starting kernel...
  </code></pre>
  
  <p>And then the Monitor turns black and shows "no signal", also the serial console doesn't show any more information.</p>
  
  <p>I've played around with the bootargs that are provided to the Kernel, but I didn't find a working scenario.</p>
  
  <p>Does anybody have an idea?</p>
  
  <p>As I said, both the U-Boot and the Kernel seem to work, but U-Boot can't boot the Kernel...</p>
  
  <p>Thanks,
  VanDahlen</p>