dt: Remove booting-without-of.rst

[linux-2.6-microblaze.git] / Documentation / mips / booting.rst

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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.