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/*
* This is the modern bootblock. It is used by platforms which select
* C_ENVIRONMENT_BOOTBLOCK, and it prepares the system for C environment runtime
* setup. The actual setup is done by hardware-specific code.
*
* It provides a bootflow similar to other architectures, and thus is considered
* to be the modern approach.
*
* This file is part of the coreboot project.
*
* Copyright (C) 2015 Alexandru Gagniuc <mr.nuke.me@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#define CR0_MP (1 << 1)
#define CR0_EM (1 << 2)
#define CR4_OSFXSR (1 << 9)
#define CR4_OSXMMEXCPT (1 << 10)
/*
* Include the old code for reset vector and protected mode entry. That code has
* withstood the test of time.
*/
#include <arch/x86/prologue.inc>
#include <cpu/x86/16bit/entry16.inc>
#include <cpu/x86/16bit/reset16.inc>
#include <cpu/x86/32bit/entry32.inc>
bootblock_protected_mode_entry:
/* Save BIST result */
movd %eax, %mm0
/* Save an early timestamp */
rdtsc
movd %eax, %mm1
movd %edx, %mm2
#if !IS_ENABLED(CONFIG_SSE)
enable_sse:
mov %cr0, %eax
and $~CR0_EM, %ax /* Clear coprocessor emulation CR0.EM */
or $CR0_MP, %ax /* Set coprocessor monitoring CR0.MP */
mov %eax, %cr0
mov %cr4, %eax
or $(CR4_OSFXSR | CR4_OSXMMEXCPT), %ax
mov %eax, %cr4
#endif /* IS_ENABLED(CONFIG_SSE) */
/* We're done. Now it's up to platform-specific code */
jmp bootblock_pre_c_entry
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