iPXE
efix86_nap.c
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1 /*
2  * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <ipxe/nap.h>
27 #include <ipxe/efi/efi.h>
28 
29 /** @file
30  *
31  * iPXE CPU sleeping API for EFI
32  *
33  */
34 
35 /**
36  * Sleep until next interrupt
37  *
38  */
39 static void efix86_cpu_nap ( void ) {
40  /*
41  * I can't find any EFI API that allows us to put the CPU to
42  * sleep. The CpuSleep() function is defined in CpuLib.h, but
43  * isn't part of any exposed protocol so we have no way to
44  * call it.
45  *
46  * The EFI shell doesn't seem to bother sleeping the CPU; it
47  * just sits there idly burning power.
48  *
49  */
50  __asm__ __volatile__ ( "hlt" );
51 }
52 
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
CPU sleeping.
static void efix86_cpu_nap(void)
Sleep until next interrupt.
Definition: efix86_nap.c:39
PROVIDE_NAP(efix86, cpu_nap, efix86_cpu_nap)
EFI API.
__asm__ __volatile__("\n1:\n\t" "movb -1(%2,%1), %%al\n\t" "stosb\n\t" "loop 1b\n\t" "xorl %%eax, %%eax\n\t" "mov %3, %1\n\t" "rep stosb\n\t" :"=&D"(discard_D), "=&c"(discard_c) :"r"(data), "g"(pad_len), "0"(value0), "1"(len) :"eax")
__asm__(".section \".rodata\", \"a\", " PROGBITS "\n\t" "\nprivate_key_data:\n\t" ".size private_key_data, ( . - private_key_data )\n\t" ".equ private_key_len, ( . - private_key_data )\n\t" ".previous\n\t")
void cpu_nap(void)
Sleep until next CPU interrupt.