arch/arm/mach-omap2/prm44xx.c - kernel/msm-4.9 - Gitiles

 /*
  * OMAP4 PRM module functions
  *
  * Copyright (C) 2011-2012 Texas Instruments, Inc.
  * Copyright (C) 2010 Nokia Corporation
  * Benoît Cousson
  * Paul Walmsley
  * Rajendra Nayak <rnayak@ti.com>
  *
  * 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.
  */

 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/io.h>


 #include "soc.h"
 #include "iomap.h"
 #include "common.h"
 #include "vp.h"
 #include "prm44xx.h"
 #include "prm-regbits-44xx.h"
 #include "prcm44xx.h"
 #include "prminst44xx.h"
 #include "powerdomain.h"

 /* Static data */

 static const struct omap_prcm_irq omap4_prcm_irqs[] = {
 	OMAP_PRCM_IRQ("wkup",   0,      0),
 	OMAP_PRCM_IRQ("io",     9,      1),
 };

 static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
 	.ack			= OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 	.mask			= OMAP4_PRM_IRQENABLE_MPU_OFFSET,
 	.nr_regs		= 2,
 	.irqs			= omap4_prcm_irqs,
 	.nr_irqs		= ARRAY_SIZE(omap4_prcm_irqs),
 	.irq			= 11 + OMAP44XX_IRQ_GIC_START,
 	.read_pending_irqs	= &omap44xx_prm_read_pending_irqs,
 	.ocp_barrier		= &omap44xx_prm_ocp_barrier,
 	.save_and_clear_irqen	= &omap44xx_prm_save_and_clear_irqen,
 	.restore_irqen		= &omap44xx_prm_restore_irqen,
 };

 /*
  * omap44xx_prm_reset_src_map - map from bits in the PRM_RSTST
  *   hardware register (which are specific to OMAP44xx SoCs) to reset
  *   source ID bit shifts (which is an OMAP SoC-independent
  *   enumeration)
  */
 static struct prm_reset_src_map omap44xx_prm_reset_src_map[] = {
 	{ OMAP4430_RST_GLOBAL_WARM_SW_SHIFT,
 	  OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
 	{ OMAP4430_RST_GLOBAL_COLD_SW_SHIFT,
 	  OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
 	{ OMAP4430_MPU_SECURITY_VIOL_RST_SHIFT,
 	  OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
 	{ OMAP4430_MPU_WDT_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
 	{ OMAP4430_SECURE_WDT_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
 	{ OMAP4430_EXTERNAL_WARM_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
 	{ OMAP4430_VDD_MPU_VOLT_MGR_RST_SHIFT,
 	  OMAP_VDD_MPU_VM_RST_SRC_ID_SHIFT },
 	{ OMAP4430_VDD_IVA_VOLT_MGR_RST_SHIFT,
 	  OMAP_VDD_IVA_VM_RST_SRC_ID_SHIFT },
 	{ OMAP4430_VDD_CORE_VOLT_MGR_RST_SHIFT,
 	  OMAP_VDD_CORE_VM_RST_SRC_ID_SHIFT },
 	{ OMAP4430_ICEPICK_RST_SHIFT, OMAP_ICEPICK_RST_SRC_ID_SHIFT },
 	{ OMAP4430_C2C_RST_SHIFT, OMAP_C2C_RST_SRC_ID_SHIFT },
 	{ -1, -1 },
 };

 /* PRM low-level functions */

 /* Read a register in a CM/PRM instance in the PRM module */
 u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
 {
 	return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
 }

 /* Write into a register in a CM/PRM instance in the PRM module */
 void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
 {
 	__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
 }

 /* Read-modify-write a register in a PRM module. Caller must lock */
 u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
 {
 	u32 v;

 	v = omap4_prm_read_inst_reg(inst, reg);
 	v &= ~mask;
 	v |= bits;
 	omap4_prm_write_inst_reg(v, inst, reg);

 	return v;
 }

 /* PRM VP */

 /*
  * struct omap4_vp - OMAP4 VP register access description.
  * @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
  * @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
  */
 struct omap4_vp {
 	u32 irqstatus_mpu;
 	u32 tranxdone_status;
 };

 static struct omap4_vp omap4_vp[] = {
 	[OMAP4_VP_VDD_MPU_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
 		.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
 	},
 	[OMAP4_VP_VDD_IVA_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 		.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
 	},
 	[OMAP4_VP_VDD_CORE_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 		.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
 	},
 };

 u32 omap4_prm_vp_check_txdone(u8 vp_id)
 {
 	struct omap4_vp *vp = &omap4_vp[vp_id];
 	u32 irqstatus;

 	irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 						OMAP4430_PRM_OCP_SOCKET_INST,
 						vp->irqstatus_mpu);
 	return irqstatus & vp->tranxdone_status;
 }

 void omap4_prm_vp_clear_txdone(u8 vp_id)
 {
 	struct omap4_vp *vp = &omap4_vp[vp_id];

 	omap4_prminst_write_inst_reg(vp->tranxdone_status,
 				     OMAP4430_PRM_PARTITION,
 				     OMAP4430_PRM_OCP_SOCKET_INST,
 				     vp->irqstatus_mpu);
 };

 u32 omap4_prm_vcvp_read(u8 offset)
 {
 	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 					   OMAP4430_PRM_DEVICE_INST, offset);
 }

 void omap4_prm_vcvp_write(u32 val, u8 offset)
 {
 	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
 				     OMAP4430_PRM_DEVICE_INST, offset);
 }

 u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
 {
 	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
 					       OMAP4430_PRM_PARTITION,
 					       OMAP4430_PRM_DEVICE_INST,
 					       offset);
 }

 static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
 {
 	u32 mask, st;

 	/* XXX read mask from RAM? */
 	mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				       irqen_offs);
 	st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);

 	return mask & st;
 }

 /**
  * omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
  * @events: ptr to two consecutive u32s, preallocated by caller
  *
  * Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
  * MPU IRQs, and store the result into the two u32s pointed to by @events.
  * No return value.
  */
 void omap44xx_prm_read_pending_irqs(unsigned long *events)
 {
 	events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
 					  OMAP4_PRM_IRQSTATUS_MPU_OFFSET);

 	events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
 					  OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
 }

 /**
  * omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
  *
  * Force any buffered writes to the PRM IP block to complete.  Needed
  * by the PRM IRQ handler, which reads and writes directly to the IP
  * block, to avoid race conditions after acknowledging or clearing IRQ
  * bits.  No return value.
  */
 void omap44xx_prm_ocp_barrier(void)
 {
 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				OMAP4_REVISION_PRM_OFFSET);
 }

 /**
  * omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
  * @saved_mask: ptr to a u32 array to save IRQENABLE bits
  *
  * Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
  * @saved_mask.  @saved_mask must be allocated by the caller.
  * Intended to be used in the PRM interrupt handler suspend callback.
  * The OCP barrier is needed to ensure the write to disable PRM
  * interrupts reaches the PRM before returning; otherwise, spurious
  * interrupts might occur.  No return value.
  */
 void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
 {
 	saved_mask[0] =
 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 					OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
 	saved_mask[1] =
 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 					OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);

 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);

 	/* OCP barrier */
 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				OMAP4_REVISION_PRM_OFFSET);
 }

 /**
  * omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
  * @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
  *
  * Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
  * @saved_mask.  Intended to be used in the PRM interrupt handler resume
  * callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
  * No OCP barrier should be needed here; any pending PRM interrupts will fire
  * once the writes reach the PRM.  No return value.
  */
 void omap44xx_prm_restore_irqen(u32 *saved_mask)
 {
 	omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
 	omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
 }

 /**
  * omap44xx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
  *
  * Clear any previously-latched I/O wakeup events and ensure that the
  * I/O wakeup gates are aligned with the current mux settings.  Works
  * by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
  * deasserting WUCLKIN and waiting for WUCLKOUT to be deasserted.
  * No return value. XXX Are the final two steps necessary?
  */
 void omap44xx_prm_reconfigure_io_chain(void)
 {
 	int i = 0;

 	/* Trigger WUCLKIN enable */
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
 				    OMAP4430_WUCLK_CTRL_MASK,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 	omap_test_timeout(
 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
 		   OMAP4430_WUCLK_STATUS_MASK) >>
 		  OMAP4430_WUCLK_STATUS_SHIFT) == 1),
 		MAX_IOPAD_LATCH_TIME, i);
 	if (i == MAX_IOPAD_LATCH_TIME)
 		pr_warn("PRM: I/O chain clock line assertion timed out\n");

 	/* Trigger WUCLKIN disable */
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 	omap_test_timeout(
 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
 		   OMAP4430_WUCLK_STATUS_MASK) >>
 		  OMAP4430_WUCLK_STATUS_SHIFT) == 0),
 		MAX_IOPAD_LATCH_TIME, i);
 	if (i == MAX_IOPAD_LATCH_TIME)
 		pr_warn("PRM: I/O chain clock line deassertion timed out\n");

 	return;
 }

 /**
  * omap44xx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
  *
  * Activates the I/O wakeup event latches and allows events logged by
  * those latches to signal a wakeup event to the PRCM.  For I/O wakeups
  * to occur, WAKEUPENABLE bits must be set in the pad mux registers, and
  * omap44xx_prm_reconfigure_io_chain() must be called.  No return value.
  */
 static void __init omap44xx_prm_enable_io_wakeup(void)
 {
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
 				    OMAP4430_GLOBAL_WUEN_MASK,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 }

 /**
  * omap44xx_prm_read_reset_sources - return the last SoC reset source
  *
  * Return a u32 representing the last reset sources of the SoC.  The
  * returned reset source bits are standardized across OMAP SoCs.
  */
 static u32 omap44xx_prm_read_reset_sources(void)
 {
 	struct prm_reset_src_map *p;
 	u32 r = 0;
 	u32 v;

 	v = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				    OMAP4_RM_RSTST);

 	p = omap44xx_prm_reset_src_map;
 	while (p->reg_shift >= 0 && p->std_shift >= 0) {
 		if (v & (1 << p->reg_shift))
 			r |= 1 << p->std_shift;
 		p++;
 	}

 	return r;
 }

 /**
  * omap44xx_prm_was_any_context_lost_old - was module hardware context lost?
  * @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
  * @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
  * @idx: CONTEXT register offset
  *
  * Return 1 if any bits were set in the *_CONTEXT_* register
  * identified by (@part, @inst, @idx), which means that some context
  * was lost for that module; otherwise, return 0.
  */
 static bool omap44xx_prm_was_any_context_lost_old(u8 part, s16 inst, u16 idx)
 {
 	return (omap4_prminst_read_inst_reg(part, inst, idx)) ? 1 : 0;
 }

 /**
  * omap44xx_prm_clear_context_lost_flags_old - clear context loss flags
  * @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
  * @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
  * @idx: CONTEXT register offset
  *
  * Clear hardware context loss bits for the module identified by
  * (@part, @inst, @idx).  No return value.  XXX Writes to reserved bits;
  * is there a way to avoid this?
  */
 static void omap44xx_prm_clear_context_loss_flags_old(u8 part, s16 inst,
 						      u16 idx)
 {
 	omap4_prminst_write_inst_reg(0xffffffff, part, inst, idx);
 }

 /* Powerdomain low-level functions */

 static int omap4_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
 {
 	omap4_prminst_rmw_inst_reg_bits(OMAP_POWERSTATE_MASK,
 					(pwrst << OMAP_POWERSTATE_SHIFT),
 					pwrdm->prcm_partition,
 					pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
 	return 0;
 }

 static int omap4_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
 {
 	u32 v;

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);
 	v &= OMAP_POWERSTATE_MASK;
 	v >>= OMAP_POWERSTATE_SHIFT;

 	return v;
 }

 static int omap4_pwrdm_read_pwrst(struct powerdomain *pwrdm)
 {
 	u32 v;

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTST);
 	v &= OMAP_POWERSTATEST_MASK;
 	v >>= OMAP_POWERSTATEST_SHIFT;

 	return v;
 }

 static int omap4_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
 {
 	u32 v;

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTST);
 	v &= OMAP4430_LASTPOWERSTATEENTERED_MASK;
 	v >>= OMAP4430_LASTPOWERSTATEENTERED_SHIFT;

 	return v;
 }

 static int omap4_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
 {
 	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOWPOWERSTATECHANGE_MASK,
 					(1 << OMAP4430_LOWPOWERSTATECHANGE_SHIFT),
 					pwrdm->prcm_partition,
 					pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
 	return 0;
 }

 static int omap4_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
 {
 	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LASTPOWERSTATEENTERED_MASK,
 					OMAP4430_LASTPOWERSTATEENTERED_MASK,
 					pwrdm->prcm_partition,
 					pwrdm->prcm_offs, OMAP4_PM_PWSTST);
 	return 0;
 }

 static int omap4_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
 {
 	u32 v;

 	v = pwrst << __ffs(OMAP4430_LOGICRETSTATE_MASK);
 	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOGICRETSTATE_MASK, v,
 					pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);

 	return 0;
 }

 static int omap4_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
 				    u8 pwrst)
 {
 	u32 m;

 	m = omap2_pwrdm_get_mem_bank_onstate_mask(bank);

 	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
 					pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);

 	return 0;
 }

 static int omap4_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
 				     u8 pwrst)
 {
 	u32 m;

 	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

 	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
 					pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);

 	return 0;
 }

 static int omap4_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
 {
 	u32 v;

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTST);
 	v &= OMAP4430_LOGICSTATEST_MASK;
 	v >>= OMAP4430_LOGICSTATEST_SHIFT;

 	return v;
 }

 static int omap4_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
 {
 	u32 v;

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);
 	v &= OMAP4430_LOGICRETSTATE_MASK;
 	v >>= OMAP4430_LOGICRETSTATE_SHIFT;

 	return v;
 }

 /**
  * omap4_pwrdm_read_prev_logic_pwrst - read the previous logic powerstate
  * @pwrdm: struct powerdomain * to read the state for
  *
  * Reads the previous logic powerstate for a powerdomain. This
  * function must determine the previous logic powerstate by first
  * checking the previous powerstate for the domain. If that was OFF,
  * then logic has been lost. If previous state was RETENTION, the
  * function reads the setting for the next retention logic state to
  * see the actual value.  In every other case, the logic is
  * retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
  * depending whether the logic was retained or not.
  */
 static int omap4_pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
 {
 	int state;

 	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

 	if (state == PWRDM_POWER_OFF)
 		return PWRDM_POWER_OFF;

 	if (state != PWRDM_POWER_RET)
 		return PWRDM_POWER_RET;

 	return omap4_pwrdm_read_logic_retst(pwrdm);
 }

 static int omap4_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
 {
 	u32 m, v;

 	m = omap2_pwrdm_get_mem_bank_stst_mask(bank);

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTST);
 	v &= m;
 	v >>= __ffs(m);

 	return v;
 }

 static int omap4_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
 {
 	u32 m, v;

 	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

 	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
 					OMAP4_PM_PWSTCTRL);
 	v &= m;
 	v >>= __ffs(m);

 	return v;
 }

 /**
  * omap4_pwrdm_read_prev_mem_pwrst - reads the previous memory powerstate
  * @pwrdm: struct powerdomain * to read mem powerstate for
  * @bank: memory bank index
  *
  * Reads the previous memory powerstate for a powerdomain. This
  * function must determine the previous memory powerstate by first
  * checking the previous powerstate for the domain. If that was OFF,
  * then logic has been lost. If previous state was RETENTION, the
  * function reads the setting for the next memory retention state to
  * see the actual value.  In every other case, the logic is
  * retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
  * depending whether logic was retained or not.
  */
 static int omap4_pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
 {
 	int state;

 	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

 	if (state == PWRDM_POWER_OFF)
 		return PWRDM_POWER_OFF;

 	if (state != PWRDM_POWER_RET)
 		return PWRDM_POWER_RET;

 	return omap4_pwrdm_read_mem_retst(pwrdm, bank);
 }

 static int omap4_pwrdm_wait_transition(struct powerdomain *pwrdm)
 {
 	u32 c = 0;

 	/*
 	 * REVISIT: pwrdm_wait_transition() may be better implemented
 	 * via a callback and a periodic timer check -- how long do we expect
 	 * powerdomain transitions to take?
 	 */

 	/* XXX Is this udelay() value meaningful? */
 	while ((omap4_prminst_read_inst_reg(pwrdm->prcm_partition,
 					    pwrdm->prcm_offs,
 					    OMAP4_PM_PWSTST) &
 		OMAP_INTRANSITION_MASK) &&
 	       (c++ < PWRDM_TRANSITION_BAILOUT))
 		udelay(1);

 	if (c > PWRDM_TRANSITION_BAILOUT) {
 		pr_err("powerdomain: %s: waited too long to complete transition\n",
 		       pwrdm->name);
 		return -EAGAIN;
 	}

 	pr_debug("powerdomain: completed transition in %d loops\n", c);

 	return 0;
 }

 struct pwrdm_ops omap4_pwrdm_operations = {
 	.pwrdm_set_next_pwrst	= omap4_pwrdm_set_next_pwrst,
 	.pwrdm_read_next_pwrst	= omap4_pwrdm_read_next_pwrst,
 	.pwrdm_read_pwrst	= omap4_pwrdm_read_pwrst,
 	.pwrdm_read_prev_pwrst	= omap4_pwrdm_read_prev_pwrst,
 	.pwrdm_set_lowpwrstchange	= omap4_pwrdm_set_lowpwrstchange,
 	.pwrdm_clear_all_prev_pwrst	= omap4_pwrdm_clear_all_prev_pwrst,
 	.pwrdm_set_logic_retst	= omap4_pwrdm_set_logic_retst,
 	.pwrdm_read_logic_pwrst	= omap4_pwrdm_read_logic_pwrst,
 	.pwrdm_read_prev_logic_pwrst	= omap4_pwrdm_read_prev_logic_pwrst,
 	.pwrdm_read_logic_retst	= omap4_pwrdm_read_logic_retst,
 	.pwrdm_read_mem_pwrst	= omap4_pwrdm_read_mem_pwrst,
 	.pwrdm_read_mem_retst	= omap4_pwrdm_read_mem_retst,
 	.pwrdm_read_prev_mem_pwrst	= omap4_pwrdm_read_prev_mem_pwrst,
 	.pwrdm_set_mem_onst	= omap4_pwrdm_set_mem_onst,
 	.pwrdm_set_mem_retst	= omap4_pwrdm_set_mem_retst,
 	.pwrdm_wait_transition	= omap4_pwrdm_wait_transition,
 };

 /*
  * XXX document
  */
 static struct prm_ll_data omap44xx_prm_ll_data = {
 	.read_reset_sources = &omap44xx_prm_read_reset_sources,
 	.was_any_context_lost_old = &omap44xx_prm_was_any_context_lost_old,
 	.clear_context_loss_flags_old = &omap44xx_prm_clear_context_loss_flags_old,
 };

 int __init omap44xx_prm_init(void)
 {
 	if (!cpu_is_omap44xx())
 		return 0;

 	return prm_register(&omap44xx_prm_ll_data);
 }

 static int __init omap44xx_prm_late_init(void)
 {
 	if (!cpu_is_omap44xx())
 		return 0;

 	omap44xx_prm_enable_io_wakeup();

 	return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
 }
 subsys_initcall(omap44xx_prm_late_init);

 static void __exit omap44xx_prm_exit(void)
 {
 	if (!cpu_is_omap44xx())
 		return;

 	/* Should never happen */
 	WARN(prm_unregister(&omap44xx_prm_ll_data),
 	     "%s: prm_ll_data function pointer mismatch\n", __func__);
 }
 __exitcall(omap44xx_prm_exit);
	/*
	* OMAP4 PRM module functions
	*
	* Copyright (C) 2011-2012 Texas Instruments, Inc.
	* Copyright (C) 2010 Nokia Corporation
	* Benoît Cousson
	* Paul Walmsley
	* Rajendra Nayak <rnayak@ti.com>
	*
	* 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.
	*/

	#include <linux/kernel.h>
	#include <linux/delay.h>
	#include <linux/errno.h>
	#include <linux/err.h>
	#include <linux/io.h>


	#include "soc.h"
	#include "iomap.h"
	#include "common.h"
	#include "vp.h"
	#include "prm44xx.h"
	#include "prm-regbits-44xx.h"
	#include "prcm44xx.h"
	#include "prminst44xx.h"
	#include "powerdomain.h"

	/* Static data */

	static const struct omap_prcm_irq omap4_prcm_irqs[] = {
	OMAP_PRCM_IRQ("wkup", 0, 0),
	OMAP_PRCM_IRQ("io", 9, 1),
	};

	static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
	.ack = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.mask = OMAP4_PRM_IRQENABLE_MPU_OFFSET,
	.nr_regs = 2,
	.irqs = omap4_prcm_irqs,
	.nr_irqs = ARRAY_SIZE(omap4_prcm_irqs),
	.irq = 11 + OMAP44XX_IRQ_GIC_START,
	.read_pending_irqs = &omap44xx_prm_read_pending_irqs,
	.ocp_barrier = &omap44xx_prm_ocp_barrier,
	.save_and_clear_irqen = &omap44xx_prm_save_and_clear_irqen,
	.restore_irqen = &omap44xx_prm_restore_irqen,
	};

	/*
	* omap44xx_prm_reset_src_map - map from bits in the PRM_RSTST
	* hardware register (which are specific to OMAP44xx SoCs) to reset
	* source ID bit shifts (which is an OMAP SoC-independent
	* enumeration)
	*/
	static struct prm_reset_src_map omap44xx_prm_reset_src_map[] = {
	{ OMAP4430_RST_GLOBAL_WARM_SW_SHIFT,
	OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
	{ OMAP4430_RST_GLOBAL_COLD_SW_SHIFT,
	OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
	{ OMAP4430_MPU_SECURITY_VIOL_RST_SHIFT,
	OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
	{ OMAP4430_MPU_WDT_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
	{ OMAP4430_SECURE_WDT_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
	{ OMAP4430_EXTERNAL_WARM_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
	{ OMAP4430_VDD_MPU_VOLT_MGR_RST_SHIFT,
	OMAP_VDD_MPU_VM_RST_SRC_ID_SHIFT },
	{ OMAP4430_VDD_IVA_VOLT_MGR_RST_SHIFT,
	OMAP_VDD_IVA_VM_RST_SRC_ID_SHIFT },
	{ OMAP4430_VDD_CORE_VOLT_MGR_RST_SHIFT,
	OMAP_VDD_CORE_VM_RST_SRC_ID_SHIFT },
	{ OMAP4430_ICEPICK_RST_SHIFT, OMAP_ICEPICK_RST_SRC_ID_SHIFT },
	{ OMAP4430_C2C_RST_SHIFT, OMAP_C2C_RST_SRC_ID_SHIFT },
	{ -1, -1 },
	};

	/* PRM low-level functions */

	/* Read a register in a CM/PRM instance in the PRM module */
	u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
	{
	return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
	}

	/* Write into a register in a CM/PRM instance in the PRM module */
	void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
	{
	__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
	}

	/* Read-modify-write a register in a PRM module. Caller must lock */
	u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
	{
	u32 v;

	v = omap4_prm_read_inst_reg(inst, reg);
	v &= ~mask;
	v \|= bits;
	omap4_prm_write_inst_reg(v, inst, reg);

	return v;
	}

	/* PRM VP */

	/*
	* struct omap4_vp - OMAP4 VP register access description.
	* @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
	* @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
	*/
	struct omap4_vp {
	u32 irqstatus_mpu;
	u32 tranxdone_status;
	};

	static struct omap4_vp omap4_vp[] = {
	[OMAP4_VP_VDD_MPU_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
	.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
	},
	[OMAP4_VP_VDD_IVA_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
	},
	[OMAP4_VP_VDD_CORE_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
	},
	};

	u32 omap4_prm_vp_check_txdone(u8 vp_id)
	{
	struct omap4_vp *vp = &omap4_vp[vp_id];
	u32 irqstatus;

	irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_OCP_SOCKET_INST,
	vp->irqstatus_mpu);
	return irqstatus & vp->tranxdone_status;
	}

	void omap4_prm_vp_clear_txdone(u8 vp_id)
	{
	struct omap4_vp *vp = &omap4_vp[vp_id];

	omap4_prminst_write_inst_reg(vp->tranxdone_status,
	OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_OCP_SOCKET_INST,
	vp->irqstatus_mpu);
	};

	u32 omap4_prm_vcvp_read(u8 offset)
	{
	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST, offset);
	}

	void omap4_prm_vcvp_write(u32 val, u8 offset)
	{
	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST, offset);
	}

	u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
	{
	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
	OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST,
	offset);
	}

	static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
	{
	u32 mask, st;

	/* XXX read mask from RAM? */
	mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	irqen_offs);
	st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);

	return mask & st;
	}

	/**
	* omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
	* @events: ptr to two consecutive u32s, preallocated by caller
	*
	* Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
	* MPU IRQs, and store the result into the two u32s pointed to by @events.
	* No return value.
	*/
	void omap44xx_prm_read_pending_irqs(unsigned long *events)
	{
	events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
	OMAP4_PRM_IRQSTATUS_MPU_OFFSET);

	events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
	OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
	}

	/**
	* omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
	*
	* Force any buffered writes to the PRM IP block to complete. Needed
	* by the PRM IRQ handler, which reads and writes directly to the IP
	* block, to avoid race conditions after acknowledging or clearing IRQ
	* bits. No return value.
	*/
	void omap44xx_prm_ocp_barrier(void)
	{
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_REVISION_PRM_OFFSET);
	}

	/**
	* omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
	* @saved_mask: ptr to a u32 array to save IRQENABLE bits
	*
	* Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
	* @saved_mask. @saved_mask must be allocated by the caller.
	* Intended to be used in the PRM interrupt handler suspend callback.
	* The OCP barrier is needed to ensure the write to disable PRM
	* interrupts reaches the PRM before returning; otherwise, spurious
	* interrupts might occur. No return value.
	*/
	void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
	{
	saved_mask[0] =
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
	saved_mask[1] =
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);

	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_OFFSET);
	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);

	/* OCP barrier */
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_REVISION_PRM_OFFSET);
	}

	/**
	* omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
	* @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
	*
	* Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
	* @saved_mask. Intended to be used in the PRM interrupt handler resume
	* callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
	* No OCP barrier should be needed here; any pending PRM interrupts will fire
	* once the writes reach the PRM. No return value.
	*/
	void omap44xx_prm_restore_irqen(u32 *saved_mask)
	{
	omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_OFFSET);
	omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
	}

	/**
	* omap44xx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
	*
	* Clear any previously-latched I/O wakeup events and ensure that the
	* I/O wakeup gates are aligned with the current mux settings. Works
	* by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
	* deasserting WUCLKIN and waiting for WUCLKOUT to be deasserted.
	* No return value. XXX Are the final two steps necessary?
	*/
	void omap44xx_prm_reconfigure_io_chain(void)
	{
	int i = 0;

	/* Trigger WUCLKIN enable */
	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
	OMAP4430_WUCLK_CTRL_MASK,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	omap_test_timeout(
	(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET) &
	OMAP4430_WUCLK_STATUS_MASK) >>
	OMAP4430_WUCLK_STATUS_SHIFT) == 1),
	MAX_IOPAD_LATCH_TIME, i);
	if (i == MAX_IOPAD_LATCH_TIME)
	pr_warn("PRM: I/O chain clock line assertion timed out\n");

	/* Trigger WUCLKIN disable */
	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	omap_test_timeout(
	(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET) &
	OMAP4430_WUCLK_STATUS_MASK) >>
	OMAP4430_WUCLK_STATUS_SHIFT) == 0),
	MAX_IOPAD_LATCH_TIME, i);
	if (i == MAX_IOPAD_LATCH_TIME)
	pr_warn("PRM: I/O chain clock line deassertion timed out\n");

	return;
	}

	/**
	* omap44xx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
	*
	* Activates the I/O wakeup event latches and allows events logged by
	* those latches to signal a wakeup event to the PRCM. For I/O wakeups
	* to occur, WAKEUPENABLE bits must be set in the pad mux registers, and
	* omap44xx_prm_reconfigure_io_chain() must be called. No return value.
	*/
	static void __init omap44xx_prm_enable_io_wakeup(void)
	{
	omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
	OMAP4430_GLOBAL_WUEN_MASK,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	}

	/**
	* omap44xx_prm_read_reset_sources - return the last SoC reset source
	*
	* Return a u32 representing the last reset sources of the SoC. The
	* returned reset source bits are standardized across OMAP SoCs.
	*/
	static u32 omap44xx_prm_read_reset_sources(void)
	{
	struct prm_reset_src_map *p;
	u32 r = 0;
	u32 v;

	v = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_RM_RSTST);

	p = omap44xx_prm_reset_src_map;
	while (p->reg_shift >= 0 && p->std_shift >= 0) {
	if (v & (1 << p->reg_shift))
	r \|= 1 << p->std_shift;
	p++;
	}

	return r;
	}

	/**
	* omap44xx_prm_was_any_context_lost_old - was module hardware context lost?
	* @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
	* @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
	* @idx: CONTEXT register offset
	*
	* Return 1 if any bits were set in the _CONTEXT_ register
	* identified by (@part, @inst, @idx), which means that some context
	* was lost for that module; otherwise, return 0.
	*/
	static bool omap44xx_prm_was_any_context_lost_old(u8 part, s16 inst, u16 idx)
	{
	return (omap4_prminst_read_inst_reg(part, inst, idx)) ? 1 : 0;
	}

	/**
	* omap44xx_prm_clear_context_lost_flags_old - clear context loss flags
	* @part: PRM partition ID (e.g., OMAP4430_PRM_PARTITION)
	* @inst: PRM instance offset (e.g., OMAP4430_PRM_MPU_INST)
	* @idx: CONTEXT register offset
	*
	* Clear hardware context loss bits for the module identified by
	* (@part, @inst, @idx). No return value. XXX Writes to reserved bits;
	* is there a way to avoid this?
	*/
	static void omap44xx_prm_clear_context_loss_flags_old(u8 part, s16 inst,
	u16 idx)
	{
	omap4_prminst_write_inst_reg(0xffffffff, part, inst, idx);
	}

	/* Powerdomain low-level functions */

	static int omap4_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
	{
	omap4_prminst_rmw_inst_reg_bits(OMAP_POWERSTATE_MASK,
	(pwrst << OMAP_POWERSTATE_SHIFT),
	pwrdm->prcm_partition,
	pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
	return 0;
	}

	static int omap4_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
	{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);
	v &= OMAP_POWERSTATE_MASK;
	v >>= OMAP_POWERSTATE_SHIFT;

	return v;
	}

	static int omap4_pwrdm_read_pwrst(struct powerdomain *pwrdm)
	{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTST);
	v &= OMAP_POWERSTATEST_MASK;
	v >>= OMAP_POWERSTATEST_SHIFT;

	return v;
	}

	static int omap4_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
	{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTST);
	v &= OMAP4430_LASTPOWERSTATEENTERED_MASK;
	v >>= OMAP4430_LASTPOWERSTATEENTERED_SHIFT;

	return v;
	}

	static int omap4_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
	{
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOWPOWERSTATECHANGE_MASK,
	(1 << OMAP4430_LOWPOWERSTATECHANGE_SHIFT),
	pwrdm->prcm_partition,
	pwrdm->prcm_offs, OMAP4_PM_PWSTCTRL);
	return 0;
	}

	static int omap4_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
	{
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LASTPOWERSTATEENTERED_MASK,
	OMAP4430_LASTPOWERSTATEENTERED_MASK,
	pwrdm->prcm_partition,
	pwrdm->prcm_offs, OMAP4_PM_PWSTST);
	return 0;
	}

	static int omap4_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
	{
	u32 v;

	v = pwrst << __ffs(OMAP4430_LOGICRETSTATE_MASK);
	omap4_prminst_rmw_inst_reg_bits(OMAP4430_LOGICRETSTATE_MASK, v,
	pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);

	return 0;
	}

	static int omap4_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
	u8 pwrst)
	{
	u32 m;

	m = omap2_pwrdm_get_mem_bank_onstate_mask(bank);

	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
	pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);

	return 0;
	}

	static int omap4_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
	u8 pwrst)
	{
	u32 m;

	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

	omap4_prminst_rmw_inst_reg_bits(m, (pwrst << __ffs(m)),
	pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);

	return 0;
	}

	static int omap4_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
	{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTST);
	v &= OMAP4430_LOGICSTATEST_MASK;
	v >>= OMAP4430_LOGICSTATEST_SHIFT;

	return v;
	}

	static int omap4_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
	{
	u32 v;

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);
	v &= OMAP4430_LOGICRETSTATE_MASK;
	v >>= OMAP4430_LOGICRETSTATE_SHIFT;

	return v;
	}

	/**
	* omap4_pwrdm_read_prev_logic_pwrst - read the previous logic powerstate
	* @pwrdm: struct powerdomain * to read the state for
	*
	* Reads the previous logic powerstate for a powerdomain. This
	* function must determine the previous logic powerstate by first
	* checking the previous powerstate for the domain. If that was OFF,
	* then logic has been lost. If previous state was RETENTION, the
	* function reads the setting for the next retention logic state to
	* see the actual value. In every other case, the logic is
	* retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
	* depending whether the logic was retained or not.
	*/
	static int omap4_pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
	{
	int state;

	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

	if (state == PWRDM_POWER_OFF)
	return PWRDM_POWER_OFF;

	if (state != PWRDM_POWER_RET)
	return PWRDM_POWER_RET;

	return omap4_pwrdm_read_logic_retst(pwrdm);
	}

	static int omap4_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
	{
	u32 m, v;

	m = omap2_pwrdm_get_mem_bank_stst_mask(bank);

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTST);
	v &= m;
	v >>= __ffs(m);

	return v;
	}

	static int omap4_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
	{
	u32 m, v;

	m = omap2_pwrdm_get_mem_bank_retst_mask(bank);

	v = omap4_prminst_read_inst_reg(pwrdm->prcm_partition, pwrdm->prcm_offs,
	OMAP4_PM_PWSTCTRL);
	v &= m;
	v >>= __ffs(m);

	return v;
	}

	/**
	* omap4_pwrdm_read_prev_mem_pwrst - reads the previous memory powerstate
	* @pwrdm: struct powerdomain * to read mem powerstate for
	* @bank: memory bank index
	*
	* Reads the previous memory powerstate for a powerdomain. This
	* function must determine the previous memory powerstate by first
	* checking the previous powerstate for the domain. If that was OFF,
	* then logic has been lost. If previous state was RETENTION, the
	* function reads the setting for the next memory retention state to
	* see the actual value. In every other case, the logic is
	* retained. Returns either PWRDM_POWER_OFF or PWRDM_POWER_RET
	* depending whether logic was retained or not.
	*/
	static int omap4_pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
	{
	int state;

	state = omap4_pwrdm_read_prev_pwrst(pwrdm);

	if (state == PWRDM_POWER_OFF)
	return PWRDM_POWER_OFF;

	if (state != PWRDM_POWER_RET)
	return PWRDM_POWER_RET;

	return omap4_pwrdm_read_mem_retst(pwrdm, bank);
	}

	static int omap4_pwrdm_wait_transition(struct powerdomain *pwrdm)
	{
	u32 c = 0;

	/*
	* REVISIT: pwrdm_wait_transition() may be better implemented
	* via a callback and a periodic timer check -- how long do we expect
	* powerdomain transitions to take?
	*/

	/* XXX Is this udelay() value meaningful? */
	while ((omap4_prminst_read_inst_reg(pwrdm->prcm_partition,
	pwrdm->prcm_offs,
	OMAP4_PM_PWSTST) &
	OMAP_INTRANSITION_MASK) &&
	(c++ < PWRDM_TRANSITION_BAILOUT))
	udelay(1);

	if (c > PWRDM_TRANSITION_BAILOUT) {
	pr_err("powerdomain: %s: waited too long to complete transition\n",
	pwrdm->name);
	return -EAGAIN;
	}

	pr_debug("powerdomain: completed transition in %d loops\n", c);

	return 0;
	}

	struct pwrdm_ops omap4_pwrdm_operations = {
	.pwrdm_set_next_pwrst = omap4_pwrdm_set_next_pwrst,
	.pwrdm_read_next_pwrst = omap4_pwrdm_read_next_pwrst,
	.pwrdm_read_pwrst = omap4_pwrdm_read_pwrst,
	.pwrdm_read_prev_pwrst = omap4_pwrdm_read_prev_pwrst,
	.pwrdm_set_lowpwrstchange = omap4_pwrdm_set_lowpwrstchange,
	.pwrdm_clear_all_prev_pwrst = omap4_pwrdm_clear_all_prev_pwrst,
	.pwrdm_set_logic_retst = omap4_pwrdm_set_logic_retst,
	.pwrdm_read_logic_pwrst = omap4_pwrdm_read_logic_pwrst,
	.pwrdm_read_prev_logic_pwrst = omap4_pwrdm_read_prev_logic_pwrst,
	.pwrdm_read_logic_retst = omap4_pwrdm_read_logic_retst,
	.pwrdm_read_mem_pwrst = omap4_pwrdm_read_mem_pwrst,
	.pwrdm_read_mem_retst = omap4_pwrdm_read_mem_retst,
	.pwrdm_read_prev_mem_pwrst = omap4_pwrdm_read_prev_mem_pwrst,
	.pwrdm_set_mem_onst = omap4_pwrdm_set_mem_onst,
	.pwrdm_set_mem_retst = omap4_pwrdm_set_mem_retst,
	.pwrdm_wait_transition = omap4_pwrdm_wait_transition,
	};

	/*
	* XXX document
	*/
	static struct prm_ll_data omap44xx_prm_ll_data = {
	.read_reset_sources = &omap44xx_prm_read_reset_sources,
	.was_any_context_lost_old = &omap44xx_prm_was_any_context_lost_old,
	.clear_context_loss_flags_old = &omap44xx_prm_clear_context_loss_flags_old,
	};

	int __init omap44xx_prm_init(void)
	{
	if (!cpu_is_omap44xx())
	return 0;

	return prm_register(&omap44xx_prm_ll_data);
	}

	static int __init omap44xx_prm_late_init(void)
	{
	if (!cpu_is_omap44xx())
	return 0;

	omap44xx_prm_enable_io_wakeup();

	return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
	}
	subsys_initcall(omap44xx_prm_late_init);

	static void __exit omap44xx_prm_exit(void)
	{
	if (!cpu_is_omap44xx())
	return;

	/* Should never happen */
	WARN(prm_unregister(&omap44xx_prm_ll_data),
	"%s: prm_ll_data function pointer mismatch\n", __func__);
	}
	__exitcall(omap44xx_prm_exit);