1 # SPDX-License-Identifier: GPL-2.0+
2 # Copyright (c) 2016 Google, Inc
3 # Written by Simon Glass <sjg@chromium.org>
5 # Entry-type module for the 16-bit x86 start-up code for U-Boot
8 from entry import Entry
9 from blob import Entry_blob
11 class Entry_x86_start16(Entry_blob):
12 """x86 16-bit start-up code for U-Boot
14 Properties / Entry arguments:
15 - filename: Filename of u-boot-x86-16bit.bin (default
16 'u-boot-x86-16bit.bin')
18 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
19 must be placed at a particular address. This entry holds that code. It is
20 typically placed at offset CONFIG_SYS_X86_START16. The code is responsible
21 for changing to 32-bit mode and jumping to U-Boot's entry point, which
22 requires 32-bit mode (for 32-bit U-Boot).
24 For 64-bit U-Boot, the 'x86_start16_spl' entry type is used instead.
26 def __init__(self, section, etype, node):
27 Entry_blob.__init__(self, section, etype, node)
29 def GetDefaultFilename(self):
30 return 'u-boot-x86-16bit.bin'