On Thu, 9 Mar 2017 08:08:20 -0500 Tom Rini trini@konsulko.com wrote:
On Thu, Mar 02, 2017 at 01:04:16PM -0600, Franklin S Cooper Jr wrote:
Runtime U-boot dtb selection is generally a two step process. First step is to simply use an initial generic dtb. The second step is to select the dtb and perhaps execute additional code ones U-boot knows what board it is running on. Embedded_dtb_select handles the second step by allowing board specific code to run and perform what ever necessary configuration that is needed.
So I'm not 100% sure on how to proceed here exactly. We have a few things to consider. First, I bet the generic dtb is good enough for loading up and booting to Linux (and loading/passing a different, complete and board specific DTB). Second, we have the (reasonable) set of patches and discussion to make the DTB that we use available easily so that it could be passed on to Linux (or EFI apps or whatever). So, this is probably the right thing to do in the long run, but is also another data point in the "but we need to think and talk about if some platforms really shouldn't be shipping their full FT on the HW somewhere".
It might also happen that somebody would like to have one "blessed" u-boot binary stored in one place and then only change u-boot DTB stored on another memory region (like eMMC, NOR).
The above also seems like a valid use case, especially when one wants to support device for a long time (many DTBs) and avoid uncontrolled grown of final u-boot.img binary size (as this is now the case for TI).
Signed-off-by: Franklin S Cooper Jr fcooper@ti.com
[snip]
+config DTB_RESELECT
- bool "Support swapping dtbs at a later point in boot"
- depends on FIT_EMBED
- default n
This is the default, you can drop it.
Best regards,
Lukasz Majewski
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