serial: pxa: fine-tune clk useage

[linux/fpc-iii.git] / arch / arm / mach-omap2 / prm3xxx.c

/*
 * 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"

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,
};

/*
 * 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_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 (omap3_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 struct prm_ll_data omap3xxx_prm_ll_data = {
        .read_reset_sources = &omap3xxx_prm_read_reset_sources,
};

int __init omap3xxx_prm_init(void)
{
        if (!cpu_is_omap34xx())
                return 0;

        return prm_register(&omap3xxx_prm_ll_data);
}

static int __init omap3xxx_prm_late_init(void)
{
        int ret;

        if (!cpu_is_omap34xx())
                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;
}
subsys_initcall(omap3xxx_prm_late_init);

static void __exit omap3xxx_prm_exit(void)
{
        if (!cpu_is_omap34xx())
                return;

        /* Should never happen */
        WARN(prm_unregister(&omap3xxx_prm_ll_data),
             "%s: prm_ll_data function pointer mismatch\n", __func__);
}
__exitcall(omap3xxx_prm_exit);