linux/arch/arm/mach-shmobile/sleep-sh7372.S
Magnus Damm f7dadb3793 PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
The sh7372 contains a power domain named A4S which in turn
contains power domains for both I/O Devices and CPU cores.

At this point only System wide Suspend-to-RAM is supported,
but the the hardware can also support CPUIdle. With more
efforts in the future CPUIdle can work with bot A4S and A3SM.

Tested on the sh7372 Mackerel board.

[rjw: Rebased on top of the current linux-pm tree.]

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2011-12-25 23:39:03 +01:00

96 lines
2.6 KiB
ArmAsm

/*
* sh7372 lowlevel sleep code for "Core Standby Mode"
*
* Copyright (C) 2011 Magnus Damm
*
* In "Core Standby Mode" the ARM core is off, but L2 cache is still on
*
* Based on mach-omap2/sleep34xx.S
*
* (C) Copyright 2007 Texas Instruments
* Karthik Dasu <karthik-dp@ti.com>
*
* (C) Copyright 2004 Texas Instruments, <www.ti.com>
* Richard Woodruff <r-woodruff2@ti.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.
*
* 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 <linux/init.h>
#include <asm/memory.h>
#include <asm/assembler.h>
#if defined(CONFIG_SUSPEND) || defined(CONFIG_CPU_IDLE)
.align 12
.text
.global sh7372_resume_core_standby_sysc
sh7372_resume_core_standby_sysc:
ldr pc, 1f
1: .long cpu_resume - PAGE_OFFSET + PLAT_PHYS_OFFSET
#define SPDCR 0xe6180008
/* A3SM & A4S power down */
.global sh7372_do_idle_sysc
sh7372_do_idle_sysc:
mov r8, r0 /* sleep mode passed in r0 */
/*
* Clear the SCTLR.C bit to prevent further data cache
* allocation. Clearing SCTLR.C would make all the data accesses
* strongly ordered and would not hit the cache.
*/
mrc p15, 0, r0, c1, c0, 0
bic r0, r0, #(1 << 2) @ Disable the C bit
mcr p15, 0, r0, c1, c0, 0
isb
/* disable L2 cache in the aux control register */
mrc p15, 0, r10, c1, c0, 1
bic r10, r10, #2
mcr p15, 0, r10, c1, c0, 1
/*
* Invalidate data cache again.
*/
ldr r1, kernel_flush
blx r1
/*
* The kernel doesn't interwork: v7_flush_dcache_all in particluar will
* always return in Thumb state when CONFIG_THUMB2_KERNEL is enabled.
* This sequence switches back to ARM. Note that .align may insert a
* nop: bx pc needs to be word-aligned in order to work.
*/
THUMB( .thumb )
THUMB( .align )
THUMB( bx pc )
THUMB( nop )
.arm
/* Data memory barrier and Data sync barrier */
dsb
dmb
/* SYSC power down */
ldr r0, =SPDCR
str r8, [r0]
1:
b 1b
kernel_flush:
.word v7_flush_dcache_all
#endif