xref: /rk3399_rockchip-uboot/doc/README.multi-dtb-fit (revision 2bbcffb1d32577bf249357776460c34feea487b5)
1*2bbcffb1SJean-Jacques HiblotMULTI DTB FIT
2*2bbcffb1SJean-Jacques Hiblot
3*2bbcffb1SJean-Jacques HiblotThe purpose of this feature is to enable u-boot to select its DTB from a FIT
4*2bbcffb1SJean-Jacques Hiblotappended at the end of the binary.
5*2bbcffb1SJean-Jacques Hiblot
6*2bbcffb1SJean-Jacques HiblotUsually the DTB is selected by the SPL and passed down to U-Boot. But some
7*2bbcffb1SJean-Jacques Hiblotplatforms don't use the SPL. In this case MULTI_DTB_FIT can used to provide
8*2bbcffb1SJean-Jacques HiblotU-Boot with a choice of DTBs.
9*2bbcffb1SJean-Jacques HiblotThe relevant DTBs are packed into a FIT (list provided by CONFIG__OF_LIST). The
10*2bbcffb1SJean-Jacques HiblotFIT is automatically generated at the end of the compilation and appended to
11*2bbcffb1SJean-Jacques Hiblotu-boot.bin so that U-Boot can locate it and select the correct DTB from inside
12*2bbcffb1SJean-Jacques Hiblotthe FIT.
13*2bbcffb1SJean-Jacques HiblotThe selection is done using board_fit_config_name_match() (same as what the SPL
14*2bbcffb1SJean-Jacques Hiblotuses to select the DTB for U-Boot). The selection happens during fdtdec_setup()
15*2bbcffb1SJean-Jacques Hiblotwhich is called during before relocation by board_init_f().
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