/*
 * OMAP3xxx PRM module functions
 *
 * Copyright (C) 2010-2012 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/errno.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>

#include "soc.h"
#include "common.h"
#include "vp.h"
#include "powerdomain.h"
#include "prm3xxx.h"
#include "prm2xxx_3xxx.h"
#include "cm2xxx_3xxx.h"
#include "prm-regbits-34xx.h"
#include "cm3xxx.h"
#include "cm-regbits-34xx.h"

static const struct omap_prcm_irq omap3_prcm_irqs[] = {
	OMAP_PRCM_IRQ("wkup",	0,	0),
	OMAP_PRCM_IRQ("io",	9,	1),
};

static struct omap_prcm_irq_setup omap3_prcm_irq_setup = {
	.ack			= OMAP3_PRM_IRQSTATUS_MPU_OFFSET,
	.mask			= OMAP3_PRM_IRQENABLE_MPU_OFFSET,
	.nr_regs		= 1,
	.irqs			= omap3_prcm_irqs,
	.nr_irqs		= ARRAY_SIZE(omap3_prcm_irqs),
	.irq			= 11 + OMAP_INTC_START,
	.read_pending_irqs	= &omap3xxx_prm_read_pending_irqs,
	.ocp_barrier		= &omap3xxx_prm_ocp_barrier,
	.save_and_clear_irqen	= &omap3xxx_prm_save_and_clear_irqen,
	.restore_irqen		= &omap3xxx_prm_restore_irqen,
	.reconfigure_io_chain	= &omap3xxx_prm_reconfigure_io_chain,
};

/*
 * omap3_prm_reset_src_map - map from bits in the PRM_RSTST hardware
 *   register (which are specific to OMAP3xxx SoCs) to reset source ID
 *   bit shifts (which is an OMAP SoC-independent enumeration)
 */
static struct prm_reset_src_map omap3xxx_prm_reset_src_map[] = {
	{ OMAP3430_GLOBAL_COLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
	{ OMAP3430_GLOBAL_SW_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
	{ OMAP3430_SECURITY_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
	{ OMAP3430_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
	{ OMAP3430_SECURE_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
	{ OMAP3430_EXTERNAL_WARM_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
	{ OMAP3430_VDD1_VOLTAGE_MANAGER_RST_SHIFT,
	  OMAP_VDD_MPU_VM_RST_SRC_ID_SHIFT },
	{ OMAP3430_VDD2_VOLTAGE_MANAGER_RST_SHIFT,
	  OMAP_VDD_CORE_VM_RST_SRC_ID_SHIFT },
	{ OMAP3430_ICEPICK_RST_SHIFT, OMAP_ICEPICK_RST_SRC_ID_SHIFT },
	{ OMAP3430_ICECRUSHER_RST_SHIFT, OMAP_ICECRUSHER_RST_SRC_ID_SHIFT },
	{ -1, -1 },
};

/* PRM VP */

/*
 * struct omap3_vp - OMAP3 VP register access description.
 * @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
 */
struct omap3_vp {
	u32 tranxdone_status;
};

static struct omap3_vp omap3_vp[] = {
	[OMAP3_VP_VDD_MPU_ID] = {
		.tranxdone_status = OMAP3430_VP1_TRANXDONE_ST_MASK,
	},
	[OMAP3_VP_VDD_CORE_ID] = {
		.tranxdone_status = OMAP3430_VP2_TRANXDONE_ST_MASK,
	},
};

#define MAX_VP_ID ARRAY_SIZE(omap3_vp);

u32 omap3_prm_vp_check_txdone(u8 vp_id)
{
	struct omap3_vp *vp = &omap3_vp[vp_id];
	u32 irqstatus;

	irqstatus = omap2_prm_read_mod_reg(OCP_MOD,
					   OMAP3_PRM_IRQSTATUS_MPU_OFFSET);
	return irqstatus & vp->tranxdone_status;
}

void omap3_prm_vp_clear_txdone(u8 vp_id)
{
	struct omap3_vp *vp = &omap3_vp[vp_id];

	omap2_prm_write_mod_reg(vp->tranxdone_status,
				OCP_MOD, OMAP3_PRM_IRQSTATUS_MPU_OFFSET);
}

u32 omap3_prm_vcvp_read(u8 offset)
{
	return omap2_prm_read_mod_reg(OMAP3430_GR_MOD, offset);
}

void omap3_prm_vcvp_write(u32 val, u8 offset)
{
	omap2_prm_write_mod_reg(val, OMAP3430_GR_MOD, offset);
}

u32 omap3_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
{
	return omap2_prm_rmw_mod_reg_bits(mask, bits, OMAP3430_GR_MOD, offset);
}

/**
 * omap3xxx_prm_dpll3_reset - use DPLL3 reset to reboot the OMAP SoC
 *
 * Set the DPLL3 reset bit, which should reboot the SoC.  This is the
 * recommended way to restart the SoC, considering Errata i520.  No
 * return value.
 */
void omap3xxx_prm_dpll3_reset(void)
{
	omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, OMAP3430_GR_MOD,
				   OMAP2_RM_RSTCTRL);
	/* OCP barrier */
	omap2_prm_read_mod_reg(OMAP3430_GR_MOD, OMAP2_RM_RSTCTRL);
}

/**
 * omap3xxx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
 * @events: ptr to a u32, preallocated by caller
 *
 * Read PRM_IRQSTATUS_MPU bits, AND'ed with the currently-enabled PRM
 * MPU IRQs, and store the result into the u32 pointed to by @events.
 * No return value.
 */
void omap3xxx_prm_read_pending_irqs(unsigned long *events)
{
	u32 mask, st;

	/* XXX Can the mask read be avoided (e.g., can it come from RAM?) */
	mask = omap2_prm_read_mod_reg(OCP_MOD, OMAP3_PRM_IRQENABLE_MPU_OFFSET);
	st = omap2_prm_read_mod_reg(OCP_MOD, OMAP3_PRM_IRQSTATUS_MPU_OFFSET);

	events[0] = mask & st;
}

/**
 * omap3xxx_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 omap3xxx_prm_ocp_barrier(void)
{
	omap2_prm_read_mod_reg(OCP_MOD, OMAP3_PRM_REVISION_OFFSET);
}

/**
 * omap3xxx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU reg
 * @saved_mask: ptr to a u32 array to save IRQENABLE bits
 *
 * Save the PRM_IRQENABLE_MPU register 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 omap3xxx_prm_save_and_clear_irqen(u32 *saved_mask)
{
	saved_mask[0] = omap2_prm_read_mod_reg(OCP_MOD,
					       OMAP3_PRM_IRQENABLE_MPU_OFFSET);
	omap2_prm_write_mod_reg(0, OCP_MOD, OMAP3_PRM_IRQENABLE_MPU_OFFSET);

	/* OCP barrier */
	omap2_prm_read_mod_reg(OCP_MOD, OMAP3_PRM_REVISION_OFFSET);
}

/**
 * omap3xxx_prm_restore_irqen - set PRM_IRQENABLE_MPU register from args
 * @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
 *
 * Restore the PRM_IRQENABLE_MPU register from @saved_mask.  Intended
 * to be used in the PRM interrupt handler resume callback to restore
 * values saved by omap3xxx_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 omap3xxx_prm_restore_irqen(u32 *saved_mask)
{
	omap2_prm_write_mod_reg(saved_mask[0], OCP_MOD,
				OMAP3_PRM_IRQENABLE_MPU_OFFSET);
}

/**
 * omap3xxx_prm_clear_mod_irqs - clear wake-up events from PRCM interrupt
 * @module: PRM module to clear wakeups from
 * @regs: register set to clear, 1 or 3
 * @ignore_bits: wakeup status bits to ignore
 *
 * The purpose of this function is to clear any wake-up events latched
 * in the PRCM PM_WKST_x registers. It is possible that a wake-up event
 * may occur whilst attempting to clear a PM_WKST_x register and thus
 * set another bit in this register. A while loop is used to ensure
 * that any peripheral wake-up events occurring while attempting to
 * clear the PM_WKST_x are detected and cleared.
 */
int omap3xxx_prm_clear_mod_irqs(s16 module, u8 regs, u32 ignore_bits)
{
	u32 wkst, fclk, iclk, clken;
	u16 wkst_off = (regs == 3) ? OMAP3430ES2_PM_WKST3 : PM_WKST1;
	u16 fclk_off = (regs == 3) ? OMAP3430ES2_CM_FCLKEN3 : CM_FCLKEN1;
	u16 iclk_off = (regs == 3) ? CM_ICLKEN3 : CM_ICLKEN1;
	u16 grpsel_off = (regs == 3) ?
		OMAP3430ES2_PM_MPUGRPSEL3 : OMAP3430_PM_MPUGRPSEL;
	int c = 0;

	wkst = omap2_prm_read_mod_reg(module, wkst_off);
	wkst &= omap2_prm_read_mod_reg(module, grpsel_off);
	wkst &= ~ignore_bits;
	if (wkst) {
		iclk = omap2_cm_read_mod_reg(module, iclk_off);
		fclk = omap2_cm_read_mod_reg(module, fclk_off);
		while (wkst) {
			clken = wkst;
			omap2_cm_set_mod_reg_bits(clken, module, iclk_off);
			/*
			 * For USBHOST, we don't know whether HOST1 or
			 * HOST2 woke us up, so enable both f-clocks
			 */
			if (module == OMAP3430ES2_USBHOST_MOD)
				clken |= 1 << OMAP3430ES2_EN_USBHOST2_SHIFT;
			omap2_cm_set_mod_reg_bits(clken, module, fclk_off);
			omap2_prm_write_mod_reg(wkst, module, wkst_off);
			wkst = omap2_prm_read_mod_reg(module, wkst_off);
			wkst &= ~ignore_bits;
			c++;
		}
		omap2_cm_write_mod_reg(iclk, module, iclk_off);
		omap2_cm_write_mod_reg(fclk, module, fclk_off);
	}

	return c;
}

/**
 * omap3xxx_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 clearing the ST_IO_CHAIN WKST bit.  No
 * return value.
 */
void omap3xxx_prm_reconfigure_io_chain(void)
{
	int i = 0;

	omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
				   PM_WKEN);

	omap_test_timeout(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKST) &
			  OMAP3430_ST_IO_CHAIN_MASK,
			  MAX_IOPAD_LATCH_TIME, i);
	if (i == MAX_IOPAD_LATCH_TIME)
		pr_warn("PRM: I/O chain clock line assertion timed out\n");

	omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
				     PM_WKEN);

	omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK, WKUP_MOD,
				   PM_WKST);

	omap2_prm_read_mod_reg(WKUP_MOD, PM_WKST);
}

/**
 * omap3xxx_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 omap3xxx_prm_reconfigure_io_chain() must be called.
 * No return value.
 */
static void __init omap3xxx_prm_enable_io_wakeup(void)
{
	if (prm_features & PRM_HAS_IO_WAKEUP)
		omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD,
					   PM_WKEN);
}

/**
 * omap3xxx_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 omap3xxx_prm_read_reset_sources(void)
{
	struct prm_reset_src_map *p;
	u32 r = 0;
	u32 v;

	v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);

	p = omap3xxx_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;
}

/* Powerdomain low-level functions */

static int omap3_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
{
	omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
				   (pwrst << OMAP_POWERSTATE_SHIFT),
				   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
	return 0;
}

static int omap3_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP2_PM_PWSTCTRL,
					     OMAP_POWERSTATE_MASK);
}

static int omap3_pwrdm_read_pwrst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP2_PM_PWSTST,
					     OMAP_POWERSTATEST_MASK);
}

/* Applicable only for OMAP3. Not supported on OMAP2 */
static int omap3_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP3430_PM_PREPWSTST,
					     OMAP3430_LASTPOWERSTATEENTERED_MASK);
}

static int omap3_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP2_PM_PWSTST,
					     OMAP3430_LOGICSTATEST_MASK);
}

static int omap3_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP2_PM_PWSTCTRL,
					     OMAP3430_LOGICSTATEST_MASK);
}

static int omap3_pwrdm_read_prev_logic_pwrst(struct powerdomain *pwrdm)
{
	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
					     OMAP3430_PM_PREPWSTST,
					     OMAP3430_LASTLOGICSTATEENTERED_MASK);
}

static int omap3_get_mem_bank_lastmemst_mask(u8 bank)
{
	switch (bank) {
	case 0:
		return OMAP3430_LASTMEM1STATEENTERED_MASK;
	case 1:
		return OMAP3430_LASTMEM2STATEENTERED_MASK;
	case 2:
		return OMAP3430_LASTSHAREDL2CACHEFLATSTATEENTERED_MASK;
	case 3:
		return OMAP3430_LASTL2FLATMEMSTATEENTERED_MASK;
	default:
		WARN_ON(1); /* should never happen */
		return -EEXIST;
	}
	return 0;
}

static int omap3_pwrdm_read_prev_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
{
	u32 m;

	m = omap3_get_mem_bank_lastmemst_mask(bank);

	return omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
				OMAP3430_PM_PREPWSTST, m);
}

static int omap3_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
{
	omap2_prm_write_mod_reg(0, pwrdm->prcm_offs, OMAP3430_PM_PREPWSTST);
	return 0;
}

static int omap3_pwrdm_enable_hdwr_sar(struct powerdomain *pwrdm)
{
	return omap2_prm_rmw_mod_reg_bits(0,
					  1 << OMAP3430ES2_SAVEANDRESTORE_SHIFT,
					  pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
}

static int omap3_pwrdm_disable_hdwr_sar(struct powerdomain *pwrdm)
{
	return omap2_prm_rmw_mod_reg_bits(1 << OMAP3430ES2_SAVEANDRESTORE_SHIFT,
					  0, pwrdm->prcm_offs,
					  OMAP2_PM_PWSTCTRL);
}

struct pwrdm_ops omap3_pwrdm_operations = {
	.pwrdm_set_next_pwrst	= omap3_pwrdm_set_next_pwrst,
	.pwrdm_read_next_pwrst	= omap3_pwrdm_read_next_pwrst,
	.pwrdm_read_pwrst	= omap3_pwrdm_read_pwrst,
	.pwrdm_read_prev_pwrst	= omap3_pwrdm_read_prev_pwrst,
	.pwrdm_set_logic_retst	= omap2_pwrdm_set_logic_retst,
	.pwrdm_read_logic_pwrst	= omap3_pwrdm_read_logic_pwrst,
	.pwrdm_read_logic_retst	= omap3_pwrdm_read_logic_retst,
	.pwrdm_read_prev_logic_pwrst	= omap3_pwrdm_read_prev_logic_pwrst,
	.pwrdm_set_mem_onst	= omap2_pwrdm_set_mem_onst,
	.pwrdm_set_mem_retst	= omap2_pwrdm_set_mem_retst,
	.pwrdm_read_mem_pwrst	= omap2_pwrdm_read_mem_pwrst,
	.pwrdm_read_mem_retst	= omap2_pwrdm_read_mem_retst,
	.pwrdm_read_prev_mem_pwrst	= omap3_pwrdm_read_prev_mem_pwrst,
	.pwrdm_clear_all_prev_pwrst	= omap3_pwrdm_clear_all_prev_pwrst,
	.pwrdm_enable_hdwr_sar	= omap3_pwrdm_enable_hdwr_sar,
	.pwrdm_disable_hdwr_sar	= omap3_pwrdm_disable_hdwr_sar,
	.pwrdm_wait_transition	= omap2_pwrdm_wait_transition,
};

/*
 *
 */

static int omap3xxx_prm_late_init(void);

static struct prm_ll_data omap3xxx_prm_ll_data = {
	.read_reset_sources = &omap3xxx_prm_read_reset_sources,
	.late_init = &omap3xxx_prm_late_init,
};

int __init omap3xxx_prm_init(void)
{
	if (omap3_has_io_wakeup())
		prm_features |= PRM_HAS_IO_WAKEUP;

	return prm_register(&omap3xxx_prm_ll_data);
}

static int omap3xxx_prm_late_init(void)
{
	int ret;

	if (!(prm_features & PRM_HAS_IO_WAKEUP))
		return 0;

	omap3xxx_prm_enable_io_wakeup();
	ret = omap_prcm_register_chain_handler(&omap3_prcm_irq_setup);
	if (!ret)
		irq_set_status_flags(omap_prcm_event_to_irq("io"),
				     IRQ_NOAUTOEN);

	return ret;
}

static void __exit omap3xxx_prm_exit(void)
{
	prm_unregister(&omap3xxx_prm_ll_data);
}
__exitcall(omap3xxx_prm_exit);