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original_kernel/arch/powerpc/platforms/pasemi/powersave.S

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[POWERPC] pasemi: Idle loops Powersave support on PA6T. Right now it only uses 'doze' mode, and will default to no savings (spin). Signed-off-by: Olof Johansson <olof@lixom.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-05 06:36:51 +08:00
/*
* Copyright (C) 2006-2007 PA Semi, Inc
*
* Maintained by: Olof Johansson <olof@lixom.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/ppc_asm.h>
#include <asm/cputable.h>
#include <asm/cache.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
/* Power savings opcodes since not all binutils have them at this time */
#define DOZE .long 0x4c000324
#define NAP .long 0x4c000364
#define SLEEP .long 0x4c0003a4
#define RVW .long 0x4c0003e4
/* Common sequence to do before going to any of the
* powersavings modes.
*/
#define PRE_SLEEP_SEQUENCE \
std r3,8(r1); \
ptesync ; \
ld r3,8(r1); \
1: cmpd r3,r3; \
bne 1b
_doze:
PRE_SLEEP_SEQUENCE
DOZE
b .
_GLOBAL(idle_spin)
blr
_GLOBAL(idle_doze)
LOAD_REG_ADDR(r3, _doze)
b sleep_common
/* Add more modes here later */
sleep_common:
mflr r0
std r0, 16(r1)
stdu r1,-64(r1)
[POWERPC] pasemi: Don't enter powersaving states from elevated astates When the PWRficient cpus are entered into powersavings states, the astate is automatically dropped down to 0. While we still restore it when we come out of idle, it can still cause some weird effects with respect to performance (especially since it takes a while to ramp up to higher astates). So, to avoid this, don't enter power savings when the cpufreq driver (or user) has set higher astates than 0. The restore is still required, since there's a chance the astate has been raised from the other cpu while the idling one was asleep. Signed-off-by: Olof Johansson <olof@lixom.net>
2007-11-07 23:26:06 +08:00
#ifdef CONFIG_PPC_PASEMI_CPUFREQ
std r3, 48(r1)
[POWERPC] pasemi: Idle loops Powersave support on PA6T. Right now it only uses 'doze' mode, and will default to no savings (spin). Signed-off-by: Olof Johansson <olof@lixom.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-05 06:36:51 +08:00
[POWERPC] pasemi: Don't enter powersaving states from elevated astates When the PWRficient cpus are entered into powersavings states, the astate is automatically dropped down to 0. While we still restore it when we come out of idle, it can still cause some weird effects with respect to performance (especially since it takes a while to ramp up to higher astates). So, to avoid this, don't enter power savings when the cpufreq driver (or user) has set higher astates than 0. The restore is still required, since there's a chance the astate has been raised from the other cpu while the idling one was asleep. Signed-off-by: Olof Johansson <olof@lixom.net>
2007-11-07 23:26:06 +08:00
/* Only do power savings when in astate 0 */
bl .check_astate
cmpwi r3,0
bne 1f
ld r3, 48(r1)
#endif
[POWERPC] pasemi: Idle loops Powersave support on PA6T. Right now it only uses 'doze' mode, and will default to no savings (spin). Signed-off-by: Olof Johansson <olof@lixom.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-05 06:36:51 +08:00
LOAD_REG_IMMEDIATE(r6,MSR_DR|MSR_IR|MSR_ME|MSR_EE)
mfmsr r4
andc r5,r4,r6
mtmsrd r5,0
mtctr r3
bctrl
mtmsrd r4,0
[POWERPC] pasemi: Don't enter powersaving states from elevated astates When the PWRficient cpus are entered into powersavings states, the astate is automatically dropped down to 0. While we still restore it when we come out of idle, it can still cause some weird effects with respect to performance (especially since it takes a while to ramp up to higher astates). So, to avoid this, don't enter power savings when the cpufreq driver (or user) has set higher astates than 0. The restore is still required, since there's a chance the astate has been raised from the other cpu while the idling one was asleep. Signed-off-by: Olof Johansson <olof@lixom.net>
2007-11-07 23:26:06 +08:00
1: addi r1,r1,64
[POWERPC] pasemi: Idle loops Powersave support on PA6T. Right now it only uses 'doze' mode, and will default to no savings (spin). Signed-off-by: Olof Johansson <olof@lixom.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-02-05 06:36:51 +08:00
ld r0,16(r1)
mtlr r0
blr