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+.. SPDX-License-Identifier: GPL-2.0
+
+BMIPS DeviceTree Booting
+------------------------
+
+ Some bootloaders only support a single entry point, at the start of the
+ kernel image. Other bootloaders will jump to the ELF start address.
+ Both schemes are supported; CONFIG_BOOT_RAW=y and CONFIG_NO_EXCEPT_FILL=y,
+ so the first instruction immediately jumps to kernel_entry().
+
+ Similar to the arch/arm case (b), a DT-aware bootloader is expected to
+ set up the following registers:
+
+ a0 : 0
+
+ a1 : 0xffffffff
+
+ a2 : Physical pointer to the device tree block (defined in chapter
+ II) in RAM. The device tree can be located anywhere in the first
+ 512MB of the physical address space (0x00000000 - 0x1fffffff),
+ aligned on a 64 bit boundary.
+
+ Legacy bootloaders do not use this convention, and they do not pass in a
+ DT block. In this case, Linux will look for a builtin DTB, selected via
+ CONFIG_DT_*.
+
+ This convention is defined for 32-bit systems only, as there are not
+ currently any 64-bit BMIPS implementations.