path: root/arch/arm/mach-omap2/sleep34xx.S

/*
 * linux/arch/arm/mach-omap2/sleep.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 <asm/assembler.h>
#include <plat/sram.h>
#include <mach/io.h>

#include "cm.h"
#include "prm.h"
#include "sdrc.h"
#include "control.h"

/*
 * Registers access definitions
 */
#define SDRC_SCRATCHPAD_SEM_OFFS	0xc
#define SDRC_SCRATCHPAD_SEM_V	OMAP343X_SCRATCHPAD_REGADDR\
					(SDRC_SCRATCHPAD_SEM_OFFS)
#define PM_PREPWSTST_CORE_P	OMAP3430_PRM_BASE + CORE_MOD +\
					OMAP3430_PM_PREPWSTST
#define PM_PWSTCTRL_MPU_P	OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL
#define CM_IDLEST1_CORE_V	OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1)
#define CM_IDLEST_CKGEN_V	OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST)
#define SRAM_BASE_P		OMAP3_SRAM_PA
#define CONTROL_STAT		OMAP343X_CTRL_BASE + OMAP343X_CONTROL_STATUS
#define CONTROL_MEM_RTA_CTRL	(OMAP343X_CTRL_BASE +\
					OMAP36XX_CONTROL_MEM_RTA_CTRL)

/* Move this as correct place is available */
#define SCRATCHPAD_MEM_OFFS	0x310
#define SCRATCHPAD_BASE_P	(OMAP343X_CTRL_BASE +\
					OMAP343X_CONTROL_MEM_WKUP +\
					SCRATCHPAD_MEM_OFFS)
#define SDRC_POWER_V		OMAP34XX_SDRC_REGADDR(SDRC_POWER)
#define SDRC_SYSCONFIG_P	(OMAP343X_SDRC_BASE + SDRC_SYSCONFIG)
#define SDRC_MR_0_P		(OMAP343X_SDRC_BASE + SDRC_MR_0)
#define SDRC_EMR2_0_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_0)
#define SDRC_MANUAL_0_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_0)
#define SDRC_MR_1_P		(OMAP343X_SDRC_BASE + SDRC_MR_1)
#define SDRC_EMR2_1_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_1)
#define SDRC_MANUAL_1_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_1)
#define SDRC_DLLA_STATUS_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
#define SDRC_DLLA_CTRL_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_CTRL)


/*
 * API functions
 */

	.text
/* Function call to get the restore pointer for resume from OFF */
ENTRY(get_restore_pointer)
        stmfd   sp!, {lr}     @ save registers on stack
	adr	r0, restore
        ldmfd   sp!, {pc}     @ restore regs and return
ENTRY(get_restore_pointer_sz)
        .word   . - get_restore_pointer
	.text
/* Function call to get the restore pointer for 3630 resume from OFF */
ENTRY(get_omap3630_restore_pointer)
        stmfd   sp!, {lr}     @ save registers on stack
	adr	r0, restore_3630
        ldmfd   sp!, {pc}     @ restore regs and return
ENTRY(get_omap3630_restore_pointer_sz)
        .word   . - get_omap3630_restore_pointer

	.text
/*
 * L2 cache needs to be toggled for stable OFF mode functionality on 3630.
 * This function sets up a fflag that will allow for this toggling to take
 * place on 3630. Hopefully some version in the future maynot need this
 */
ENTRY(enable_omap3630_toggle_l2_on_restore)
        stmfd   sp!, {lr}     @ save registers on stack
	/* Setup so that we will disable and enable l2 */
	mov	r1, #0x1
	str	r1, l2dis_3630
        ldmfd   sp!, {pc}     @ restore regs and return

	.text
/* Function call to get the restore pointer for for ES3 to resume from OFF */
ENTRY(get_es3_restore_pointer)
	stmfd	sp!, {lr}	@ save registers on stack
	adr	r0, restore_es3
	ldmfd	sp!, {pc}	@ restore regs and return
ENTRY(get_es3_restore_pointer_sz)
	.word	. - get_es3_restore_pointer

ENTRY(es3_sdrc_fix)
	ldr	r4, sdrc_syscfg		@ get config addr
	ldr	r5, [r4]		@ get value
	tst	r5, #0x100		@ is part access blocked
	it	eq
	biceq	r5, r5, #0x100		@ clear bit if set
	str	r5, [r4]		@ write back change
	ldr	r4, sdrc_mr_0		@ get config addr
	ldr	r5, [r4]		@ get value
	str	r5, [r4]		@ write back change
	ldr	r4, sdrc_emr2_0		@ get config addr
	ldr	r5, [r4]		@ get value
	str	r5, [r4]		@ write back change
	ldr	r4, sdrc_manual_0	@ get config addr
	mov	r5, #0x2		@ autorefresh command
	str	r5, [r4]		@ kick off refreshes
	ldr	r4, sdrc_mr_1		@ get config addr
	ldr	r5, [r4]		@ get value
	str	r5, [r4]		@ write back change
	ldr	r4, sdrc_emr2_1		@ get config addr
	ldr	r5, [r4]		@ get value
	str	r5, [r4]		@ write back change
	ldr	r4, sdrc_manual_1	@ get config addr
	mov	r5, #0x2		@ autorefresh command
	str	r5, [r4]		@ kick off refreshes
	bx	lr
sdrc_syscfg:
	.word	SDRC_SYSCONFIG_P
sdrc_mr_0:
	.word	SDRC_MR_0_P
sdrc_emr2_0:
	.word	SDRC_EMR2_0_P
sdrc_manual_0:
	.word	SDRC_MANUAL_0_P
sdrc_mr_1:
	.word	SDRC_MR_1_P
sdrc_emr2_1:
	.word	SDRC_EMR2_1_P
sdrc_manual_1:
	.word	SDRC_MANUAL_1_P
ENTRY(es3_sdrc_fix_sz)
	.word	. - es3_sdrc_fix

/* Function to call rom code to save secure ram context */
ENTRY(save_secure_ram_context)
	stmfd	sp!, {r1-r12, lr}	@ save registers on stack

	adr	r3, api_params		@ r3 points to parameters
	str	r0, [r3,#0x4]		@ r0 has sdram address
	ldr	r12, high_mask
	and	r3, r3, r12
	ldr	r12, sram_phy_addr_mask
	orr	r3, r3, r12
	mov	r0, #25			@ set service ID for PPA
	mov	r12, r0			@ copy secure service ID in r12
	mov	r1, #0			@ set task id for ROM code in r1
	mov	r2, #4			@ set some flags in r2, r6
	mov	r6, #0xff
	mcr	p15, 0, r0, c7, c10, 4	@ data write barrier
	mcr	p15, 0, r0, c7, c10, 5	@ data memory barrier
	.word	0xE1600071		@ call SMI monitor (smi #1)
	nop
	nop
	nop
	nop
	ldmfd	sp!, {r1-r12, pc}
sram_phy_addr_mask:
	.word	SRAM_BASE_P
high_mask:
	.word	0xffff
api_params:
	.word	0x4, 0x0, 0x0, 0x1, 0x1
ENTRY(save_secure_ram_context_sz)
	.word	. - save_secure_ram_context

/*
 * Forces OMAP into idle state
 *
 * omap34xx_suspend() - This bit of code just executes the WFI
 * for normal idles.
 *
 * Note: This code get's copied to internal SRAM at boot. When the OMAP
 *	 wakes up it continues execution at the point it went to sleep.
 */
ENTRY(omap34xx_cpu_suspend)
	stmfd	sp!, {r0-r12, lr}		@ save registers on stack

	/* r0 contains restore pointer in sdram */
	/* r1 contains information about saving context */
	ldr     r4, sdrc_power          @ read the SDRC_POWER register
	ldr     r5, [r4]                @ read the contents of SDRC_POWER
	orr     r5, r5, #0x40           @ enable self refresh on idle req
	str     r5, [r4]                @ write back to SDRC_POWER register

	cmp	r1, #0x0
	/* If context save is required, do that and execute wfi */
	bne	save_context_wfi
	/* Data memory barrier and Data sync barrier */
	mov	r1, #0
	mcr	p15, 0, r1, c7, c10, 4
	mcr	p15, 0, r1, c7, c10, 5

	wfi				@ wait for interrupt

	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	bl wait_sdrc_ok

	ldmfd	sp!, {r0-r12, pc}		@ restore regs and return
restore_es3:
	ldr	r5, pm_prepwstst_core_p
	ldr	r4, [r5]
	and	r4, r4, #0x3
	cmp	r4, #0x0	@ Check if previous power state of CORE is OFF
	bne	restore
	adr	r0, es3_sdrc_fix
	ldr	r1, sram_base
	ldr	r2, es3_sdrc_fix_sz
	mov	r2, r2, ror #2
copy_to_sram:
	ldmia	r0!, {r3}	@ val = *src
	stmia	r1!, {r3}	@ *dst = val
	subs	r2, r2, #0x1	@ num_words--
	bne	copy_to_sram
	ldr	r1, sram_base
	blx	r1
	b	restore

restore_3630:
	ldr	r1, pm_prepwstst_core_p
	ldr	r2, [r1]
	and	r2, r2, #0x3
	cmp	r2, #0x0	@ Check if previous power state of CORE is OFF
	bne	restore
	/* Disable RTA before giving control */
	ldr	r1, control_mem_rta
	mov	r2, #OMAP36XX_RTA_DISABLE
	str	r2, [r1]
	/* Fall thru for the remaining logic */
restore:
        /* Check what was the reason for mpu reset and store the reason in r9*/
        /* 1 - Only L1 and logic lost */
        /* 2 - Only L2 lost - In this case, we wont be here */
        /* 3 - Both L1 and L2 lost */
	ldr     r1, pm_pwstctrl_mpu
	ldr	r2, [r1]
	and     r2, r2, #0x3
	cmp     r2, #0x0	@ Check if target power state was OFF or RET
        moveq   r9, #0x3        @ MPU OFF => L1 and L2 lost
	movne	r9, #0x1	@ Only L1 and L2 lost => avoid L2 invalidation
	bne	logic_l1_restore

	ldr	r0, l2dis_3630
	cmp	r0, #0x1	@ should we disable L2 on 3630?
	bne	skipl2dis
	mrc	p15, 0, r0, c1, c0, 1
	bic	r0, r0, #2	@ disable L2 cache
	mcr	p15, 0, r0, c1, c0, 1
skipl2dis:
	ldr	r0, control_stat
	ldr	r1, [r0]
	and	r1, #0x700
	cmp	r1, #0x300
	beq	l2_inv_gp
	mov	r0, #40		@ set service ID for PPA
	mov	r12, r0		@ copy secure Service ID in r12
	mov	r1, #0		@ set task id for ROM code in r1
	mov	r2, #4		@ set some flags in r2, r6
	mov	r6, #0xff
	adr	r3, l2_inv_api_params	@ r3 points to dummy parameters
	mcr	p15, 0, r0, c7, c10, 4	@ data write barrier
	mcr	p15, 0, r0, c7, c10, 5	@ data memory barrier
	.word	0xE1600071		@ call SMI monitor (smi #1)
	/* Write to Aux control register to set some bits */
	mov	r0, #42		@ set service ID for PPA
	mov	r12, r0		@ copy secure Service ID in r12
	mov	r1, #0		@ set task id for ROM code in r1
	mov	r2, #4		@ set some flags in r2, r6
	mov	r6, #0xff
	ldr	r4, scratchpad_base
	ldr	r3, [r4, #0xBC]	@ r3 points to parameters
	mcr	p15, 0, r0, c7, c10, 4	@ data write barrier
	mcr	p15, 0, r0, c7, c10, 5	@ data memory barrier
	.word	0xE1600071		@ call SMI monitor (smi #1)

#ifdef CONFIG_OMAP3_L2_AUX_SECURE_SAVE_RESTORE
	/* Restore L2 aux control register */
	@ set service ID for PPA
	mov	r0, #CONFIG_OMAP3_L2_AUX_SECURE_SERVICE_SET_ID
	mov	r12, r0		@ copy service ID in r12
	mov	r1, #0		@ set task ID for ROM code in r1
	mov	r2, #4		@ set some flags in r2, r6
	mov	r6, #0xff
	ldr	r4, scratchpad_base
	ldr	r3, [r4, #0xBC]
	adds	r3, r3, #8	@ r3 points to parameters
	mcr	p15, 0, r0, c7, c10, 4	@ data write barrier
	mcr	p15, 0, r0, c7, c10, 5	@ data memory barrier
	.word	0xE1600071		@ call SMI monitor (smi #1)
#endif
	b	logic_l1_restore
l2_inv_api_params:
	.word   0x1, 0x00
l2_inv_gp:
	/* Execute smi to invalidate L2 cache */
	mov r12, #0x1                         @ set up to invalide L2
smi:    .word 0xE1600070		@ Call SMI monitor (smieq)
	/* Write to Aux control register to set some bits */
	ldr	r4, scratchpad_base
	ldr	r3, [r4,#0xBC]
	ldr	r0, [r3,#4]
	mov	r12, #0x3
	.word 0xE1600070	@ Call SMI monitor (smieq)
	ldr	r4, scratchpad_base
	ldr	r3, [r4,#0xBC]
	ldr	r0, [r3,#12]
	mov	r12, #0x2
	.word 0xE1600070	@ Call SMI monitor (smieq)
logic_l1_restore:
	ldr	r1, l2dis_3630
	cmp	r1, #0x1	@ Do we need to re-enable L2 on 3630?
	bne	skipl2reen
	mrc	p15, 0, r1, c1, c0, 1
	orr	r1, r1, #2	@ re-enable L2 cache
	mcr	p15, 0, r1, c1, c0, 1
skipl2reen:
	mov	r1, #0
	/* Invalidate all instruction caches to PoU
	 * and flush branch target cache */
	mcr	p15, 0, r1, c7, c5, 0

	ldr	r4, scratchpad_base
	ldr	r3, [r4,#0xBC]
	adds	r3, r3, #16
	ldmia	r3!, {r4-r6}
	mov	sp, r4
	msr	spsr_cxsf, r5
	mov	lr, r6

	ldmia	r3!, {r4-r9}
	/* Coprocessor access Control Register */
	mcr p15, 0, r4, c1, c0, 2

	/* TTBR0 */
	MCR p15, 0, r5, c2, c0, 0
	/* TTBR1 */
	MCR p15, 0, r6, c2, c0, 1
	/* Translation table base control register */
	MCR p15, 0, r7, c2, c0, 2
	/*domain access Control Register */
	MCR p15, 0, r8, c3, c0, 0
	/* data fault status Register */
	MCR p15, 0, r9, c5, c0, 0

	ldmia  r3!,{r4-r8}
	/* instruction fault status Register */
	MCR p15, 0, r4, c5, c0, 1
	/*Data Auxiliary Fault Status Register */
	MCR p15, 0, r5, c5, c1, 0
	/*Instruction Auxiliary Fault Status Register*/
	MCR p15, 0, r6, c5, c1, 1
	/*Data Fault Address Register */
	MCR p15, 0, r7, c6, c0, 0
	/*Instruction Fault Address Register*/
	MCR p15, 0, r8, c6, c0, 2
	ldmia  r3!,{r4-r7}

	/* user r/w thread and process ID */
	MCR p15, 0, r4, c13, c0, 2
	/* user ro thread and process ID */
	MCR p15, 0, r5, c13, c0, 3
	/*Privileged only thread and process ID */
	MCR p15, 0, r6, c13, c0, 4
	/* cache size selection */
	MCR p15, 2, r7, c0, c0, 0
	ldmia  r3!,{r4-r8}
	/* Data TLB lockdown registers */
	MCR p15, 0, r4, c10, c0, 0
	/* Instruction TLB lockdown registers */
	MCR p15, 0, r5, c10, c0, 1
	/* Secure or Nonsecure Vector Base Address */
	MCR p15, 0, r6, c12, c0, 0
	/* FCSE PID */
	MCR p15, 0, r7, c13, c0, 0
	/* Context PID */
	MCR p15, 0, r8, c13, c0, 1

	ldmia  r3!,{r4-r5}
	/* primary memory remap register */
	MCR p15, 0, r4, c10, c2, 0
	/*normal memory remap register */
	MCR p15, 0, r5, c10, c2, 1

	/* Restore cpsr */
	ldmia	r3!,{r4}	/*load CPSR from SDRAM*/
	msr	cpsr, r4	/*store cpsr */

	/* Enabling MMU here */
	mrc	p15, 0, r7, c2, c0, 2 /* Read TTBRControl */
	/* Extract N (0:2) bits and decide whether to use TTBR0 or TTBR1*/
	and	r7, #0x7
	cmp	r7, #0x0
	beq	usettbr0
ttbr_error:
	/* More work needs to be done to support N[0:2] value other than 0
	* So looping here so that the error can be detected
	*/
	b	ttbr_error
usettbr0:
	mrc	p15, 0, r2, c2, c0, 0
	ldr	r5, ttbrbit_mask
	and	r2, r5
	mov	r4, pc
	ldr	r5, table_index_mask
	and	r4, r5 /* r4 = 31 to 20 bits of pc */
	/* Extract the value to be written to table entry */
	ldr	r1, table_entry
	add	r1, r1, r4 /* r1 has value to be written to table entry*/
	/* Getting the address of table entry to modify */
	lsr	r4, #18
	add	r2, r4 /* r2 has the location which needs to be modified */
	/* Storing previous entry of location being modified */
	ldr	r5, scratchpad_base
	ldr	r4, [r2]
	str	r4, [r5, #0xC0]
	/* Modify the table entry */
	str	r1, [r2]
	/* Storing address of entry being modified
	 * - will be restored after enabling MMU */
	ldr	r5, scratchpad_base
	str	r2, [r5, #0xC4]

	mov	r0, #0
	mcr	p15, 0, r0, c7, c5, 4	@ Flush prefetch buffer
	mcr	p15, 0, r0, c7, c5, 6	@ Invalidate branch predictor array
	mcr	p15, 0, r0, c8, c5, 0	@ Invalidate instruction TLB
	mcr	p15, 0, r0, c8, c6, 0	@ Invalidate data TLB
	/* Restore control register  but dont enable caches here*/
	/* Caches will be enabled after restoring MMU table entry */
	ldmia	r3!, {r4}
	/* Store previous value of control register in scratchpad */
	str	r4, [r5, #0xC8]
	ldr	r2, cache_pred_disable_mask
	and	r4, r2
	mcr	p15, 0, r4, c1, c0, 0

	ldmfd	sp!, {r0-r12, pc}		@ restore regs and return
save_context_wfi:
	mov	r8, r0 /* Store SDRAM address in r8 */
	mrc	p15, 0, r5, c1, c0, 1	@ Read Auxiliary Control Register
	mov	r4, #0x1		@ Number of parameters for restore call
	stmia	r8!, {r4-r5}		@ Push parameters for restore call
	mrc	p15, 1, r5, c9, c0, 2	@ Read L2 AUX ctrl register
	stmia	r8!, {r4-r5}		@ Push parameters for restore call
        /* Check what that target sleep state is:stored in r1*/
        /* 1 - Only L1 and logic lost */
        /* 2 - Only L2 lost */
        /* 3 - Both L1 and L2 lost */
	cmp	r1, #0x2 /* Only L2 lost */
	beq	clean_l2
	cmp	r1, #0x1 /* L2 retained */
	/* r9 stores whether to clean L2 or not*/
	moveq	r9, #0x0 /* Dont Clean L2 */
	movne	r9, #0x1 /* Clean L2 */
l1_logic_lost:
	/* Store sp and spsr to SDRAM */
	mov	r4, sp
	mrs	r5, spsr
	mov	r6, lr
	stmia	r8!, {r4-r6}
	/* Save all ARM registers */
	/* Coprocessor access control register */
	mrc	p15, 0, r6, c1, c0, 2
	stmia	r8!, {r6}
	/* TTBR0, TTBR1 and Translation table base control */
	mrc	p15, 0, r4, c2, c0, 0
	mrc	p15, 0, r5, c2, c0, 1
	mrc	p15, 0, r6, c2, c0, 2
	stmia	r8!, {r4-r6}
	/* Domain access control register, data fault status register,
	and instruction fault status register */
	mrc	p15, 0, r4, c3, c0, 0
	mrc	p15, 0, r5, c5, c0, 0
	mrc	p15, 0, r6, c5, c0, 1
	stmia	r8!, {r4-r6}
	/* Data aux fault status register, instruction aux fault status,
	datat fault address register and instruction fault address register*/
	mrc	p15, 0, r4, c5, c1, 0
	mrc	p15, 0, r5, c5, c1, 1
	mrc	p15, 0, r6, c6, c0, 0
	mrc	p15, 0, r7, c6, c0, 2
	stmia	r8!, {r4-r7}
	/* user r/w thread and process ID, user r/o thread and process ID,
	priv only thread and process ID, cache size selection */
	mrc	p15, 0, r4, c13, c0, 2
	mrc	p15, 0, r5, c13, c0, 3
	mrc	p15, 0, r6, c13, c0, 4
	mrc	p15, 2, r7, c0, c0, 0
	stmia	r8!, {r4-r7}
	/* Data TLB lockdown, instruction TLB lockdown registers */
	mrc	p15, 0, r5, c10, c0, 0
	mrc	p15, 0, r6, c10, c0, 1
	stmia	r8!, {r5-r6}
	/* Secure or non secure vector base address, FCSE PID, Context PID*/
	mrc	p15, 0, r4, c12, c0, 0
	mrc	p15, 0, r5, c13, c0, 0
	mrc	p15, 0, r6, c13, c0, 1
	stmia	r8!, {r4-r6}
	/* Primary remap, normal remap registers */
	mrc	p15, 0, r4, c10, c2, 0
	mrc	p15, 0, r5, c10, c2, 1
	stmia	r8!,{r4-r5}

	/* Store current cpsr*/
	mrs	r2, cpsr
	stmia	r8!, {r2}

	mrc	p15, 0, r4, c1, c0, 0
	/* save control register */
	stmia	r8!, {r4}
clean_caches:
	/* Clean Data or unified cache to POU*/
	/* How to invalidate only L1 cache???? - #FIX_ME# */
	/* mcr	p15, 0, r11, c7, c11, 1 */
	cmp	r9, #1 /* Check whether L2 inval is required or not*/
	bne	skip_l2_inval
clean_l2:
	/*
	 * Jump out to kernel flush routine
	 *  - reuse that code is better
	 *  - it executes in a cached space so is faster than refetch per-block
	 *  - should be faster and will change with kernel
	 *  - 'might' have to copy address, load and jump to it
	 *  - lr is used since we are running in SRAM currently.
	 */
	ldr r1, kernel_flush
	mov lr, pc
	bx  r1

skip_l2_inval:
	/* Data memory barrier and Data sync barrier */
	mov     r1, #0
	mcr     p15, 0, r1, c7, c10, 4
	mcr     p15, 0, r1, c7, c10, 5

	wfi                             @ wait for interrupt
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	bl wait_sdrc_ok
	/* restore regs and return */
	ldmfd   sp!, {r0-r12, pc}

/* Make sure SDRC accesses are ok */
wait_sdrc_ok:

/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this. */
	ldr	r4, cm_idlest_ckgen
wait_dpll3_lock:
	ldr	r5, [r4]
	tst	r5, #1
	beq	wait_dpll3_lock

        ldr     r4, cm_idlest1_core
wait_sdrc_ready:
        ldr     r5, [r4]
        tst     r5, #0x2
        bne     wait_sdrc_ready
	/* allow DLL powerdown upon hw idle req */
        ldr     r4, sdrc_power
        ldr     r5, [r4]
        bic     r5, r5, #0x40
        str     r5, [r4]
is_dll_in_lock_mode:

        /* Is dll in lock mode? */
        ldr     r4, sdrc_dlla_ctrl
        ldr     r5, [r4]
        tst     r5, #0x4
        bxne    lr
        /* wait till dll locks */
wait_dll_lock_timed:
	ldr	r4, wait_dll_lock_counter
	add	r4, r4, #1
	str	r4, wait_dll_lock_counter
	ldr	r4, sdrc_dlla_status
        mov	r6, #8		/* Wait 20uS for lock */
wait_dll_lock:
	subs	r6, r6, #0x1
	beq	kick_dll
        ldr     r5, [r4]
        and     r5, r5, #0x4
        cmp     r5, #0x4
        bne     wait_dll_lock
        bx      lr

	/* disable/reenable DLL if not locked */
kick_dll:
	ldr	r4, sdrc_dlla_ctrl
	ldr	r5, [r4]
	mov	r6, r5
	bic	r6, #(1<<3)	/* disable dll */
	str	r6, [r4]
	dsb
	orr	r6, r6, #(1<<3)	/* enable dll */
	str	r6, [r4]
	dsb
	ldr	r4, kick_counter
	add	r4, r4, #1
	str	r4, kick_counter
	b	wait_dll_lock_timed

cm_idlest1_core:
	.word	CM_IDLEST1_CORE_V
cm_idlest_ckgen:
	.word	CM_IDLEST_CKGEN_V
sdrc_dlla_status:
	.word	SDRC_DLLA_STATUS_V
sdrc_dlla_ctrl:
	.word	SDRC_DLLA_CTRL_V
pm_prepwstst_core_p:
	.word	PM_PREPWSTST_CORE_P
pm_pwstctrl_mpu:
	.word	PM_PWSTCTRL_MPU_P
scratchpad_base:
	.word	SCRATCHPAD_BASE_P
sram_base:
	.word	SRAM_BASE_P + 0x8000
sdrc_power:
	.word SDRC_POWER_V
ttbrbit_mask:
	.word	0xFFFFC000
table_index_mask:
	.word	0xFFF00000
table_entry:
	.word	0x00000C02
cache_pred_disable_mask:
	.word	0xFFFFE7FB
control_stat:
	.word	CONTROL_STAT
control_mem_rta:
	.word	CONTROL_MEM_RTA_CTRL
kernel_flush:
	.word v7_flush_dcache_all
l2dis_3630:
	.word 0
	/*
	 * When exporting to userspace while the counters are in SRAM,
	 * these 2 words need to be at the end to facilitate retrival!
	 */
kick_counter:
	.word	0
wait_dll_lock_counter:
	.word	0
ENTRY(omap34xx_cpu_suspend_sz)
	.word	. - omap34xx_cpu_suspend