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loader: fdt: Try to load every possible DTB from u-boot
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Authored by manu on Jul 2 2018, 5:57 PM.
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Details

Summary

U-Boot setup a few variables :

  • fdt_addr which is the board static dtb (most of the time loaded before u-boot or coming from some hardware like a ROM)
  • fdt_addr_r which is a location in RAM that holds the DTB loaded by u-boot or before u-boot

In the case of u-boot + rpi firmware the DTB is loaded in RAM but the location
still end up in the fdt_addr variable and the fdt_addr_r variable exist.

Change the behavior so we test that a DTB exists for every possible variable :

  • fdt_addr_r is checked first as if u-boot needed to modify it the correct DTB will live there.
  • fdt_addr is checked second as if we run on a hardware with DTB in ROM it means that we what/need to run that
  • fdtaddr looks like a FreeBSD-ism but since I'm not sure leave it.

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rS FreeBSD src repository - subversion
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Event Timeline

stand/uboot/fdt/uboot_fdt.c
84 ↗(On Diff #44767)

Now comment contradicts the code, it tries fdt_addr first no fdt_addr_r. Also fdt_addr used twise. Is first instance supposed to be fdtaddr?

manu edited the summary of this revision. (Show Details)

Change fdt_addr/fdt_addr_r order

manu marked an inline comment as done.Jul 2 2018, 7:02 PM
This revision is now accepted and ready to land.Jul 2 2018, 7:03 PM
This revision was automatically updated to reflect the committed changes.