arch/arm/mach-omap2/sram242x.S - kernel/msm-4.19 - Gitiles

 /*
  * linux/arch/arm/mach-omap2/sram242x.S
  *
  * Omap2 specific functions that need to be run in internal SRAM
  *
  * (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
  *
  * Richard Woodruff notes that any changes to this code must be carefully
  * audited and tested to ensure that they don't cause a TLB miss while
  * the SDRAM is inaccessible.  Such a situation will crash the system
  * since it will cause the ARM MMU to attempt to walk the page tables.
  * These crashes may be intermittent.
  */
 #include <linux/linkage.h>

 #include <asm/assembler.h>

 #include "soc.h"
 #include "iomap.h"
 #include "prm2xxx.h"
 #include "cm2xxx_3xxx.h"
 #include "sdrc.h"

 	.text

 	.align	3
 ENTRY(omap242x_sram_ddr_init)
 	stmfd	sp!, {r0 - r12, lr}	@ save registers on stack

 	mov	r12, r2			@ capture CS1 vs CS0
 	mov	r8, r3			@ capture force parameter

 	/* frequency shift down */
 	ldr	r2, omap242x_sdi_cm_clksel2_pll	@ get address of dpllout reg
 	mov	r3, #0x1		@ value for 1x operation
 	str	r3, [r2]		@ go to L1-freq operation

 	/* voltage shift down */
 	mov r9, #0x1			@ set up for L1 voltage call
 	bl voltage_shift		@ go drop voltage

 	/* dll lock mode */
 	ldr	r11, omap242x_sdi_sdrc_dlla_ctrl	@ addr of dlla ctrl
 	ldr	r10, [r11]		@ get current val
 	cmp	r12, #0x1		@ cs1 base (2422 es2.05/1)
 	addeq	r11, r11, #0x8		@ if cs1 base, move to DLLB
 	mvn	r9, #0x4		@ mask to get clear bit2
 	and	r10, r10, r9		@ clear bit2 for lock mode.
 	orr	r10, r10, #0x8		@ make sure DLL on (es2 bit pos)
 	orr	r10, r10, #0x2		@ 90 degree phase for all below 133Mhz
 	str	r10, [r11]		@ commit to DLLA_CTRL
 	bl	i_dll_wait		@ wait for dll to lock

 	/* get dll value */
 	add	r11, r11, #0x4		@ get addr of status reg
 	ldr	r10, [r11]		@ get locked value

 	/* voltage shift up */
 	mov r9, #0x0			@ shift back to L0-voltage
 	bl voltage_shift		@ go raise voltage

 	/* frequency shift up */
 	mov	r3, #0x2		@ value for 2x operation
 	str	r3, [r2]		@ go to L0-freq operation

 	/* reset entry mode for dllctrl */
 	sub	r11, r11, #0x4		@ move from status to ctrl
 	cmp	r12, #0x1		@ normalize if cs1 based
 	subeq	r11, r11, #0x8		@ possibly back to DLLA
 	cmp	r8, #0x1		@ if forced unlock exit
 	orreq	r1, r1, #0x4		@ make sure exit with unlocked value
 	str	r1, [r11]		@ restore DLLA_CTRL high value
 	add	r11, r11, #0x8		@ move to DLLB_CTRL addr
 	str	r1, [r11]		@ set value DLLB_CTRL
 	bl	i_dll_wait		@ wait for possible lock

 	/* set up for return, DDR should be good */
 	str r10, [r0]			@ write dll_status and return counter
 	ldmfd	sp!, {r0 - r12, pc}	@ restore regs and return

 	/* ensure the DLL has relocked */
 i_dll_wait:
 	mov	r4, #0x800		@ delay DLL relock, min 0x400 L3 clocks
 i_dll_delay:
 	subs	r4, r4, #0x1
 	bne	i_dll_delay
 	mov	pc, lr

 	/*
 	 * shift up or down voltage, use R9 as input to tell level.
 	 * wait for it to finish, use 32k sync counter, 1tick=31uS.
 	 */
 voltage_shift:
 	ldr	r4, omap242x_sdi_prcm_voltctrl	@ get addr of volt ctrl.
 	ldr	r5, [r4]		@ get value.
 	ldr	r6, prcm_mask_val	@ get value of mask
 	and	r5, r5, r6		@ apply mask to clear bits
 	orr	r5, r5, r9		@ bulld value for L0/L1-volt operation.
 	str	r5, [r4]		@ set up for change.
 	mov	r3, #0x4000		@ get val for force
 	orr	r5, r5, r3		@ build value for force
 	str	r5, [r4]		@ Force transition to L1

 	ldr	r3, omap242x_sdi_timer_32ksynct_cr	@ get addr of counter
 	ldr	r5, [r3]		@ get value
 	add	r5, r5, #0x3		@ give it at most 93uS
 volt_delay:
 	ldr	r7, [r3]		@ get timer value
 	cmp	r5, r7			@ time up?
 	bhi	volt_delay		@ not yet->branch
 	mov	pc, lr			@ back to caller.

 omap242x_sdi_cm_clksel2_pll:
 	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2)
 omap242x_sdi_sdrc_dlla_ctrl:
 	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)
 omap242x_sdi_prcm_voltctrl:
 	.word OMAP2420_PRCM_VOLTCTRL
 prcm_mask_val:
 	.word 0xFFFF3FFC
 omap242x_sdi_timer_32ksynct_cr:
 	.word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010)
 ENTRY(omap242x_sram_ddr_init_sz)
 	.word	. - omap242x_sram_ddr_init

 /*
  * Reprograms memory timings.
  * r0 = [PRCM_FULL | PRCM_HALF] r1 = SDRC_DLLA_CTRL value r2 = [DDR | SDR]
  * PRCM_FULL = 2, PRCM_HALF = 1, DDR = 1, SDR = 0
  */
 	.align	3
 ENTRY(omap242x_sram_reprogram_sdrc)
 	stmfd	sp!, {r0 - r10, lr}	@ save registers on stack
 	mov	r3, #0x0		@ clear for mrc call
 	mcr	p15, 0, r3, c7, c10, 4	@ memory barrier, finish ARM SDR/DDR
 	nop
 	nop
 	ldr	r6, omap242x_srs_sdrc_rfr_ctrl	@ get addr of refresh reg
 	ldr	r5, [r6]		@ get value
 	mov	r5, r5, lsr #8		@ isolate rfr field and drop burst

 	cmp	r0, #0x1		@ going to half speed?
 	movne	r9, #0x0		@ if up set flag up for pre up, hi volt

 	blne	voltage_shift_c		@ adjust voltage

 	cmp	r0, #0x1		@ going to half speed (post branch link)
 	moveq	r5, r5, lsr #1		@ divide by 2 if to half
 	movne	r5, r5, lsl #1		@ mult by 2 if to full
 	mov	r5, r5, lsl #8		@ put rfr field back into place
 	add	r5, r5, #0x1		@ turn on burst of 1
 	ldr	r4, omap242x_srs_cm_clksel2_pll	@ get address of out reg
 	ldr	r3, [r4]		@ get curr value
 	orr	r3, r3, #0x3
 	bic	r3, r3, #0x3		@ clear lower bits
 	orr	r3, r3, r0		@ new state value
 	str	r3, [r4]		@ set new state (pll/x, x=1 or 2)
 	nop
 	nop

 	moveq	r9, #0x1		@ if speed down, post down, drop volt
 	bleq	voltage_shift_c

 	mcr	p15, 0, r3, c7, c10, 4	@ memory barrier
 	str	r5, [r6]		@ set new RFR_1 value
 	add	r6, r6, #0x30		@ get RFR_2 addr
 	str	r5, [r6]		@ set RFR_2
 	nop
 	cmp	r2, #0x1		@ (SDR or DDR) do we need to adjust DLL
 	bne	freq_out		@ leave if SDR, no DLL function

 	/* With DDR, we need to take care of the DLL for the frequency change */
 	ldr	r2, omap242x_srs_sdrc_dlla_ctrl	@ addr of dlla ctrl
 	str	r1, [r2]		@ write out new SDRC_DLLA_CTRL
 	add	r2, r2, #0x8		@ addr to SDRC_DLLB_CTRL
 	str	r1, [r2]		@ commit to SDRC_DLLB_CTRL
 	mov	r1, #0x2000		@ wait DLL relock, min 0x400 L3 clocks
 dll_wait:
 	subs	r1, r1, #0x1
 	bne	dll_wait
 freq_out:
 	ldmfd	sp!, {r0 - r10, pc}	@ restore regs and return

     /*
      * shift up or down voltage, use R9 as input to tell level.
      *	wait for it to finish, use 32k sync counter, 1tick=31uS.
      */
 voltage_shift_c:
 	ldr	r10, omap242x_srs_prcm_voltctrl	@ get addr of volt ctrl
 	ldr	r8, [r10]		@ get value
 	ldr	r7, ddr_prcm_mask_val	@ get value of mask
 	and	r8, r8, r7		@ apply mask to clear bits
 	orr	r8, r8, r9		@ bulld value for L0/L1-volt operation.
 	str	r8, [r10]		@ set up for change.
 	mov	r7, #0x4000		@ get val for force
 	orr	r8, r8, r7		@ build value for force
 	str	r8, [r10]		@ Force transition to L1

 	ldr	r10, omap242x_srs_timer_32ksynct	@ get addr of counter
 	ldr	r8, [r10]		@ get value
 	add	r8, r8, #0x2		@ give it at most 62uS (min 31+)
 volt_delay_c:
 	ldr	r7, [r10]		@ get timer value
 	cmp	r8, r7			@ time up?
 	bhi	volt_delay_c		@ not yet->branch
 	mov	pc, lr			@ back to caller

 omap242x_srs_cm_clksel2_pll:
 	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2)
 omap242x_srs_sdrc_dlla_ctrl:
 	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)
 omap242x_srs_sdrc_rfr_ctrl:
 	.word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0)
 omap242x_srs_prcm_voltctrl:
 	.word OMAP2420_PRCM_VOLTCTRL
 ddr_prcm_mask_val:
 	.word 0xFFFF3FFC
 omap242x_srs_timer_32ksynct:
 	.word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010)

 ENTRY(omap242x_sram_reprogram_sdrc_sz)
 	.word	. - omap242x_sram_reprogram_sdrc

 /*
  * Set dividers and pll. Also recalculate DLL value for DDR and unlock mode.
  */
 	.align	3
 ENTRY(omap242x_sram_set_prcm)
 	stmfd	sp!, {r0-r12, lr}	@ regs to stack
 	adr	r4, pbegin		@ addr of preload start
 	adr	r8, pend		@ addr of preload end
 	mcrr	p15, 1, r8, r4, c12	@ preload into icache
 pbegin:
 	/* move into fast relock bypass */
 	ldr	r8, omap242x_ssp_pll_ctl	@ get addr
 	ldr	r5, [r8]		@ get val
 	mvn	r6, #0x3		@ clear mask
 	and	r5, r5, r6		@ clear field
 	orr	r7, r5, #0x2		@ fast relock val
 	str	r7, [r8]		@ go to fast relock
 	ldr	r4, omap242x_ssp_pll_stat	@ addr of stat
 block:
 	/* wait for bypass */
 	ldr	r8, [r4]		@ stat value
 	and	r8, r8, #0x3		@ mask for stat
 	cmp	r8, #0x1		@ there yet
 	bne	block			@ loop if not

 	/* set new dpll dividers _after_ in bypass */
 	ldr	r4, omap242x_ssp_pll_div	@ get addr
 	str	r0, [r4]		@ set dpll ctrl val

 	ldr	r4, omap242x_ssp_set_config	@ get addr
 	mov	r8, #1			@ valid cfg msk
 	str	r8, [r4]		@ make dividers take

 	mov	r4, #100		@ dead spin a bit
 wait_a_bit:
 	subs	r4, r4, #1		@ dec loop
 	bne	wait_a_bit		@ delay done?

 	/* check if staying in bypass */
 	cmp	r2, #0x1		@ stay in bypass?
 	beq	pend			@ jump over dpll relock

 	/* relock DPLL with new vals */
 	ldr	r5, omap242x_ssp_pll_stat	@ get addr
 	ldr	r4, omap242x_ssp_pll_ctl	@ get addr
 	orr	r8, r7, #0x3		@ val for lock dpll
 	str	r8, [r4]		@ set val
 	mov	r0, #1000		@ dead spin a bit
 wait_more:
 	subs	r0, r0, #1		@ dec loop
 	bne	wait_more		@ delay done?
 wait_lock:
 	ldr	r8, [r5]		@ get lock val
 	and	r8, r8, #3		@ isolate field
 	cmp	r8, #2			@ locked?
 	bne	wait_lock		@ wait if not
 pend:
 	/* update memory timings & briefly lock dll */
 	ldr	r4, omap242x_ssp_sdrc_rfr	@ get addr
 	str	r1, [r4]		@ update refresh timing
 	ldr	r11, omap242x_ssp_dlla_ctrl	@ get addr of DLLA ctrl
 	ldr	r10, [r11]		@ get current val
 	mvn	r9, #0x4		@ mask to get clear bit2
 	and	r10, r10, r9		@ clear bit2 for lock mode
 	orr	r10, r10, #0x8		@ make sure DLL on (es2 bit pos)
 	str	r10, [r11]		@ commit to DLLA_CTRL
 	add	r11, r11, #0x8		@ move to dllb
 	str	r10, [r11]		@ hit DLLB also

 	mov	r4, #0x800		@ relock time (min 0x400 L3 clocks)
 wait_dll_lock:
 	subs	r4, r4, #0x1
 	bne	wait_dll_lock
 	nop
 	ldmfd	sp!, {r0-r12, pc}	@ restore regs and return

 omap242x_ssp_set_config:
 	.word OMAP2420_PRCM_CLKCFG_CTRL
 omap242x_ssp_pll_ctl:
 	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKEN)
 omap242x_ssp_pll_stat:
 	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_IDLEST)
 omap242x_ssp_pll_div:
 	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL1)
 omap242x_ssp_sdrc_rfr:
 	.word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0)
 omap242x_ssp_dlla_ctrl:
 	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)

 ENTRY(omap242x_sram_set_prcm_sz)
 	.word	. - omap242x_sram_set_prcm
	/*
	* linux/arch/arm/mach-omap2/sram242x.S
	*
	* Omap2 specific functions that need to be run in internal SRAM
	*
	* (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
	*
	* Richard Woodruff notes that any changes to this code must be carefully
	* audited and tested to ensure that they don't cause a TLB miss while
	* the SDRAM is inaccessible. Such a situation will crash the system
	* since it will cause the ARM MMU to attempt to walk the page tables.
	* These crashes may be intermittent.
	*/
	#include <linux/linkage.h>

	#include <asm/assembler.h>

	#include "soc.h"
	#include "iomap.h"
	#include "prm2xxx.h"
	#include "cm2xxx_3xxx.h"
	#include "sdrc.h"

	.text

	.align 3
	ENTRY(omap242x_sram_ddr_init)
	stmfd sp!, {r0 - r12, lr} @ save registers on stack

	mov r12, r2 @ capture CS1 vs CS0
	mov r8, r3 @ capture force parameter

	/* frequency shift down */
	ldr r2, omap242x_sdi_cm_clksel2_pll @ get address of dpllout reg
	mov r3, #0x1 @ value for 1x operation
	str r3, [r2] @ go to L1-freq operation

	/* voltage shift down */
	mov r9, #0x1 @ set up for L1 voltage call
	bl voltage_shift @ go drop voltage

	/* dll lock mode */
	ldr r11, omap242x_sdi_sdrc_dlla_ctrl @ addr of dlla ctrl
	ldr r10, [r11] @ get current val
	cmp r12, #0x1 @ cs1 base (2422 es2.05/1)
	addeq r11, r11, #0x8 @ if cs1 base, move to DLLB
	mvn r9, #0x4 @ mask to get clear bit2
	and r10, r10, r9 @ clear bit2 for lock mode.
	orr r10, r10, #0x8 @ make sure DLL on (es2 bit pos)
	orr r10, r10, #0x2 @ 90 degree phase for all below 133Mhz
	str r10, [r11] @ commit to DLLA_CTRL
	bl i_dll_wait @ wait for dll to lock

	/* get dll value */
	add r11, r11, #0x4 @ get addr of status reg
	ldr r10, [r11] @ get locked value

	/* voltage shift up */
	mov r9, #0x0 @ shift back to L0-voltage
	bl voltage_shift @ go raise voltage

	/* frequency shift up */
	mov r3, #0x2 @ value for 2x operation
	str r3, [r2] @ go to L0-freq operation

	/* reset entry mode for dllctrl */
	sub r11, r11, #0x4 @ move from status to ctrl
	cmp r12, #0x1 @ normalize if cs1 based
	subeq r11, r11, #0x8 @ possibly back to DLLA
	cmp r8, #0x1 @ if forced unlock exit
	orreq r1, r1, #0x4 @ make sure exit with unlocked value
	str r1, [r11] @ restore DLLA_CTRL high value
	add r11, r11, #0x8 @ move to DLLB_CTRL addr
	str r1, [r11] @ set value DLLB_CTRL
	bl i_dll_wait @ wait for possible lock

	/* set up for return, DDR should be good */
	str r10, [r0] @ write dll_status and return counter
	ldmfd sp!, {r0 - r12, pc} @ restore regs and return

	/* ensure the DLL has relocked */
	i_dll_wait:
	mov r4, #0x800 @ delay DLL relock, min 0x400 L3 clocks
	i_dll_delay:
	subs r4, r4, #0x1
	bne i_dll_delay
	mov pc, lr

	/*
	* shift up or down voltage, use R9 as input to tell level.
	* wait for it to finish, use 32k sync counter, 1tick=31uS.
	*/
	voltage_shift:
	ldr r4, omap242x_sdi_prcm_voltctrl @ get addr of volt ctrl.
	ldr r5, [r4] @ get value.
	ldr r6, prcm_mask_val @ get value of mask
	and r5, r5, r6 @ apply mask to clear bits
	orr r5, r5, r9 @ bulld value for L0/L1-volt operation.
	str r5, [r4] @ set up for change.
	mov r3, #0x4000 @ get val for force
	orr r5, r5, r3 @ build value for force
	str r5, [r4] @ Force transition to L1

	ldr r3, omap242x_sdi_timer_32ksynct_cr @ get addr of counter
	ldr r5, [r3] @ get value
	add r5, r5, #0x3 @ give it at most 93uS
	volt_delay:
	ldr r7, [r3] @ get timer value
	cmp r5, r7 @ time up?
	bhi volt_delay @ not yet->branch
	mov pc, lr @ back to caller.

	omap242x_sdi_cm_clksel2_pll:
	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2)
	omap242x_sdi_sdrc_dlla_ctrl:
	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)
	omap242x_sdi_prcm_voltctrl:
	.word OMAP2420_PRCM_VOLTCTRL
	prcm_mask_val:
	.word 0xFFFF3FFC
	omap242x_sdi_timer_32ksynct_cr:
	.word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010)
	ENTRY(omap242x_sram_ddr_init_sz)
	.word . - omap242x_sram_ddr_init

	/*
	* Reprograms memory timings.
	* r0 = [PRCM_FULL \| PRCM_HALF] r1 = SDRC_DLLA_CTRL value r2 = [DDR \| SDR]
	* PRCM_FULL = 2, PRCM_HALF = 1, DDR = 1, SDR = 0
	*/
	.align 3
	ENTRY(omap242x_sram_reprogram_sdrc)
	stmfd sp!, {r0 - r10, lr} @ save registers on stack
	mov r3, #0x0 @ clear for mrc call
	mcr p15, 0, r3, c7, c10, 4 @ memory barrier, finish ARM SDR/DDR
	nop
	nop
	ldr r6, omap242x_srs_sdrc_rfr_ctrl @ get addr of refresh reg
	ldr r5, [r6] @ get value
	mov r5, r5, lsr #8 @ isolate rfr field and drop burst

	cmp r0, #0x1 @ going to half speed?
	movne r9, #0x0 @ if up set flag up for pre up, hi volt

	blne voltage_shift_c @ adjust voltage

	cmp r0, #0x1 @ going to half speed (post branch link)
	moveq r5, r5, lsr #1 @ divide by 2 if to half
	movne r5, r5, lsl #1 @ mult by 2 if to full
	mov r5, r5, lsl #8 @ put rfr field back into place
	add r5, r5, #0x1 @ turn on burst of 1
	ldr r4, omap242x_srs_cm_clksel2_pll @ get address of out reg
	ldr r3, [r4] @ get curr value
	orr r3, r3, #0x3
	bic r3, r3, #0x3 @ clear lower bits
	orr r3, r3, r0 @ new state value
	str r3, [r4] @ set new state (pll/x, x=1 or 2)
	nop
	nop

	moveq r9, #0x1 @ if speed down, post down, drop volt
	bleq voltage_shift_c

	mcr p15, 0, r3, c7, c10, 4 @ memory barrier
	str r5, [r6] @ set new RFR_1 value
	add r6, r6, #0x30 @ get RFR_2 addr
	str r5, [r6] @ set RFR_2
	nop
	cmp r2, #0x1 @ (SDR or DDR) do we need to adjust DLL
	bne freq_out @ leave if SDR, no DLL function

	/* With DDR, we need to take care of the DLL for the frequency change */
	ldr r2, omap242x_srs_sdrc_dlla_ctrl @ addr of dlla ctrl
	str r1, [r2] @ write out new SDRC_DLLA_CTRL
	add r2, r2, #0x8 @ addr to SDRC_DLLB_CTRL
	str r1, [r2] @ commit to SDRC_DLLB_CTRL
	mov r1, #0x2000 @ wait DLL relock, min 0x400 L3 clocks
	dll_wait:
	subs r1, r1, #0x1
	bne dll_wait
	freq_out:
	ldmfd sp!, {r0 - r10, pc} @ restore regs and return

	/*
	* shift up or down voltage, use R9 as input to tell level.
	* wait for it to finish, use 32k sync counter, 1tick=31uS.
	*/
	voltage_shift_c:
	ldr r10, omap242x_srs_prcm_voltctrl @ get addr of volt ctrl
	ldr r8, [r10] @ get value
	ldr r7, ddr_prcm_mask_val @ get value of mask
	and r8, r8, r7 @ apply mask to clear bits
	orr r8, r8, r9 @ bulld value for L0/L1-volt operation.
	str r8, [r10] @ set up for change.
	mov r7, #0x4000 @ get val for force
	orr r8, r8, r7 @ build value for force
	str r8, [r10] @ Force transition to L1

	ldr r10, omap242x_srs_timer_32ksynct @ get addr of counter
	ldr r8, [r10] @ get value
	add r8, r8, #0x2 @ give it at most 62uS (min 31+)
	volt_delay_c:
	ldr r7, [r10] @ get timer value
	cmp r8, r7 @ time up?
	bhi volt_delay_c @ not yet->branch
	mov pc, lr @ back to caller

	omap242x_srs_cm_clksel2_pll:
	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL2)
	omap242x_srs_sdrc_dlla_ctrl:
	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)
	omap242x_srs_sdrc_rfr_ctrl:
	.word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0)
	omap242x_srs_prcm_voltctrl:
	.word OMAP2420_PRCM_VOLTCTRL
	ddr_prcm_mask_val:
	.word 0xFFFF3FFC
	omap242x_srs_timer_32ksynct:
	.word OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x010)

	ENTRY(omap242x_sram_reprogram_sdrc_sz)
	.word . - omap242x_sram_reprogram_sdrc

	/*
	* Set dividers and pll. Also recalculate DLL value for DDR and unlock mode.
	*/
	.align 3
	ENTRY(omap242x_sram_set_prcm)
	stmfd sp!, {r0-r12, lr} @ regs to stack
	adr r4, pbegin @ addr of preload start
	adr r8, pend @ addr of preload end
	mcrr p15, 1, r8, r4, c12 @ preload into icache
	pbegin:
	/* move into fast relock bypass */
	ldr r8, omap242x_ssp_pll_ctl @ get addr
	ldr r5, [r8] @ get val
	mvn r6, #0x3 @ clear mask
	and r5, r5, r6 @ clear field
	orr r7, r5, #0x2 @ fast relock val
	str r7, [r8] @ go to fast relock
	ldr r4, omap242x_ssp_pll_stat @ addr of stat
	block:
	/* wait for bypass */
	ldr r8, [r4] @ stat value
	and r8, r8, #0x3 @ mask for stat
	cmp r8, #0x1 @ there yet
	bne block @ loop if not

	/* set new dpll dividers _after_ in bypass */
	ldr r4, omap242x_ssp_pll_div @ get addr
	str r0, [r4] @ set dpll ctrl val

	ldr r4, omap242x_ssp_set_config @ get addr
	mov r8, #1 @ valid cfg msk
	str r8, [r4] @ make dividers take

	mov r4, #100 @ dead spin a bit
	wait_a_bit:
	subs r4, r4, #1 @ dec loop
	bne wait_a_bit @ delay done?

	/* check if staying in bypass */
	cmp r2, #0x1 @ stay in bypass?
	beq pend @ jump over dpll relock

	/* relock DPLL with new vals */
	ldr r5, omap242x_ssp_pll_stat @ get addr
	ldr r4, omap242x_ssp_pll_ctl @ get addr
	orr r8, r7, #0x3 @ val for lock dpll
	str r8, [r4] @ set val
	mov r0, #1000 @ dead spin a bit
	wait_more:
	subs r0, r0, #1 @ dec loop
	bne wait_more @ delay done?
	wait_lock:
	ldr r8, [r5] @ get lock val
	and r8, r8, #3 @ isolate field
	cmp r8, #2 @ locked?
	bne wait_lock @ wait if not
	pend:
	/* update memory timings & briefly lock dll */
	ldr r4, omap242x_ssp_sdrc_rfr @ get addr
	str r1, [r4] @ update refresh timing
	ldr r11, omap242x_ssp_dlla_ctrl @ get addr of DLLA ctrl
	ldr r10, [r11] @ get current val
	mvn r9, #0x4 @ mask to get clear bit2
	and r10, r10, r9 @ clear bit2 for lock mode
	orr r10, r10, #0x8 @ make sure DLL on (es2 bit pos)
	str r10, [r11] @ commit to DLLA_CTRL
	add r11, r11, #0x8 @ move to dllb
	str r10, [r11] @ hit DLLB also

	mov r4, #0x800 @ relock time (min 0x400 L3 clocks)
	wait_dll_lock:
	subs r4, r4, #0x1
	bne wait_dll_lock
	nop
	ldmfd sp!, {r0-r12, pc} @ restore regs and return

	omap242x_ssp_set_config:
	.word OMAP2420_PRCM_CLKCFG_CTRL
	omap242x_ssp_pll_ctl:
	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKEN)
	omap242x_ssp_pll_stat:
	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_IDLEST)
	omap242x_ssp_pll_div:
	.word OMAP2420_CM_REGADDR(PLL_MOD, CM_CLKSEL1)
	omap242x_ssp_sdrc_rfr:
	.word OMAP242X_SDRC_REGADDR(SDRC_RFR_CTRL_0)
	omap242x_ssp_dlla_ctrl:
	.word OMAP242X_SDRC_REGADDR(SDRC_DLLA_CTRL)

	ENTRY(omap242x_sram_set_prcm_sz)
	.word . - omap242x_sram_set_prcm