u-boot/board/google/common/early_init.S

/*
 * Copyright (c) 2014 Google, Inc
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

.globl early_board_init
early_board_init:
	/* Enable post codes to EC */
#ifdef CONFIG_EARLY_POST_CROS_EC
	mov    $0x1b, %ecx
	rdmsr
	and    $0x100, %eax
	test   %eax, %eax
	je     1f

	mov    $0x8000f8f0, %eax
	mov    $0xcf8, %dx
	out    %eax, (%dx)
	mov    $0xfed1c001, %eax
	mov    $0xcfc, %dx
	out    %eax, (%dx)
	mov    $0xfed1f410, %esp
	mov    (%esp), %eax
	and    $0xfffffffb, %eax
	mov    %eax, (%esp)
1:
#endif
	jmp	early_board_init_ret
x86: Add chromebook_link board This board is a 'bare' version of the existing 'link 'board. It does not require coreboot to run, but is intended to start directly from the reset vector. This initial commit has place holders for a wide range of features. These will be added in follow-on patches and series. So far it cannot be booted as there is no ROM image produced, but it does build without errors. Signed-off-by: Simon Glass <sjg@chromium.org> 10 years ago			`/*`
			`* Copyright (c) 2014 Google, Inc`
			`*`
			`* SPDX-License-Identifier: GPL-2.0+`
			`*/`

			`.globl early_board_init`
			`early_board_init:`
x86: Emit post codes in startup code for Chromebooks On x86 it is common to use 'post codes' which are 8-bit hex values emitted from the code and visible to the user. Traditionally two 7-segment displays were made available on the motherboard to show the last post code that was emitted. This allows diagnosis of a boot problem since it is possible to see where the code got to before it died. On modern hardware these codes are not normally visible. On Chromebooks they are displayed by the Embedded Controller (EC), so it is useful to emit them. We must enable this feature for the EC to see the codes, so add an option for this. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> 10 years ago			`/* Enable post codes to EC */`
			`#ifdef CONFIG_EARLY_POST_CROS_EC`
			`mov $0x1b, %ecx`
			`rdmsr`
			`and $0x100, %eax`
			`test %eax, %eax`
			`je 1f`

			`mov $0x8000f8f0, %eax`
			`mov $0xcf8, %dx`
			`out %eax, (%dx)`
			`mov $0xfed1c001, %eax`
			`mov $0xcfc, %dx`
			`out %eax, (%dx)`
			`mov $0xfed1f410, %esp`
			`mov (%esp), %eax`
			`and $0xfffffffb, %eax`
			`mov %eax, (%esp)`
			`1:`
			`#endif`
x86: Add chromebook_link board This board is a 'bare' version of the existing 'link 'board. It does not require coreboot to run, but is intended to start directly from the reset vector. This initial commit has place holders for a wide range of features. These will be added in follow-on patches and series. So far it cannot be booted as there is no ROM image produced, but it does build without errors. Signed-off-by: Simon Glass <sjg@chromium.org> 10 years ago			`jmp early_board_init_ret`