On 01/10/2015 11:44 AM, Dennis Gilmore wrote:
On Mon, 05 Jan 2015 12:55:46 -0700 Stephen Warren swarren@wwwdotorg.org wrote:
On 12/28/2014 03:09 AM, Ian Campbell wrote:
On Mon, 2014-12-22 at 13:46 -0700, Stephen Warren wrote:
[...]
+The U-Boot "syslinux" and "pxe boot" commands require a number of environment +variables be set. Default values for these variables are often hard-coded into +CONFIG_EXTRA_ENV_SETTINGS in the board's U-Boot configuration file, so that +the user doesn't have to configure them. + +fdt_addr:
- Optional. If specified a dtb to boot the system must be
available at the
- given address.
+fdt_addr_r:
- Mandatory.
Isn't this one only mandatory if ${fdt_addr} is not given?
Yes. I guess it's mandatory for at least one of fdt_addr or fdt_addr_r to be set, according to common/cmd_pxe.c:
fdt_addr_r is actually mandatory unless you do not support device tree at all, which is not expected at all anymore. The reason being that the user/distro can override the vendor supplied dtb for whatever reason, by supplying a fdt/dtb fdtdir/dtbdir entry in extlinux.conf in the past at times on calxeda hardware we had to override the dtb to work with newer kernels until we could update the systems firmware.
That's a good point. I'll revise the README again and repost a V4.