[ARM] 4731/1: S3C2412: Check for incomplete sleep

Check if the sleep command returns due to a pending interrupt
in the standby unit. If this happens, try and ack the IRQ
before re-trying the resume.

It is currently unclear whether the resume can be backed out
of at this stage as this could cause a problem with level
based interrupts.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Ben Dooks 2007-12-23 03:09:34 +01:00 committed by Russell King
parent 0baada2742
commit 332349518f
3 changed files with 72 additions and 15 deletions

View file

@ -13,7 +13,7 @@ obj-$(CONFIG_CPU_S3C2412) += s3c2412.o
obj-$(CONFIG_CPU_S3C2412) += irq.o
obj-$(CONFIG_CPU_S3C2412) += clock.o
obj-$(CONFIG_S3C2412_DMA) += dma.o
obj-$(CONFIG_S3C2412_PM) += pm.o
obj-$(CONFIG_S3C2412_PM) += pm.o sleep.o
# Machine support

View file

@ -33,6 +33,8 @@
#include <asm/plat-s3c24xx/s3c2412.h>
extern void s3c2412_sleep_enter(void);
static void s3c2412_cpu_suspend(void)
{
unsigned long tmp;
@ -43,20 +45,7 @@ static void s3c2412_cpu_suspend(void)
tmp |= S3C2412_PWRCFG_STANDBYWFI_SLEEP;
__raw_writel(tmp, S3C2412_PWRCFG);
/* issue the standby signal into the pm unit. Note, we
* issue a write-buffer drain just in case */
tmp = 0;
asm("b 1f\n\t"
".align 5\n\t"
"1:\n\t"
"mcr p15, 0, %0, c7, c10, 4\n\t"
"mcr p15, 0, %0, c7, c0, 4" :: "r" (tmp));
/* we should never get past here */
panic("sleep resumed to originator?");
s3c2412_sleep_enter();
}
static void s3c2412_pm_prepare(void)

View file

@ -0,0 +1,68 @@
/* linux/arch/arm/mach-s3c2412/sleep.S
*
* Copyright (c) 2007 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* S3C2412 Power Manager low-level sleep support
*
* 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.
*
* 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 <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/hardware.h>
#include <asm/arch/map.h>
#include <asm/arch/regs-irq.h>
.text
.global s3c2412_sleep_enter
s3c2412_sleep_enter:
mov r0, #0 /* argument for coprocessors */
ldr r1, =S3C2410_INTPND
ldr r2, =S3C2410_SRCPND
ldr r3, =S3C2410_EINTPEND
teq r0, r0
bl s3c2412_sleep_enter1
teq pc, r0
bl s3c2412_sleep_enter1
.align 5
/* this is called twice, first with the Z flag to ensure that the
* instructions have been loaded into the cache, and the second
* time to try and suspend the system.
*/
s3c2412_sleep_enter1:
mcr p15, 0, r0, c7, c10, 4
mcrne p15, 0, r0, c7, c0, 4
/* if we return from here, it is because an interrupt was
* active when we tried to shutdown. Try and ack the IRQ and
* retry, as simply returning causes the system to lock.
*/
ldrne r9, [ r1 ]
strne r9, [ r1 ]
ldrne r9, [ r2 ]
strne r9, [ r2 ]
ldrne r9, [ r3 ]
strne r9, [ r3 ]
bne s3c2412_sleep_enter1
mov pc, r14