// SPDX-License-Identifier: GPL-2.0-only
/*
 * OMAP2+ common Power & Reset Management (PRM) IP block functions
 *
 * Copyright (C) 2011 Texas Instruments, Inc.
 * Tero Kristo <t-kristo@ti.com>
 *
 * For historical purposes, the API used to configure the PRM
 * interrupt handler refers to it as the "PRCM interrupt."  The
 * underlying registers are located in the PRM on OMAP3/4.
 *
 * XXX This code should eventually be moved to a PRM driver.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk-provider.h>
#include <linux/clk/ti.h>

#include "soc.h"
#include "prm2xxx_3xxx.h"
#include "prm2xxx.h"
#include "prm3xxx.h"
#include "prm33xx.h"
#include "prm44xx.h"
#include "prm54xx.h"
#include "prm7xx.h"
#include "prcm43xx.h"
#include "common.h"
#include "clock.h"
#include "cm.h"
#include "control.h"

/*
 * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
 * XXX this is technically not needed, since
 * omap_prcm_register_chain_handler() could allocate this based on the
 * actual amount of memory needed for the SoC
 */
#define OMAP_PRCM_MAX_NR_PENDING_REG            2

/*
 * prcm_irq_chips: an array of all of the "generic IRQ chips" in use
 * by the PRCM interrupt handler code.  There will be one 'chip' per
 * PRM_{IRQSTATUS,IRQENABLE}_MPU register pair.  (So OMAP3 will have
 * one "chip" and OMAP4 will have two.)
 */
static struct irq_chip_generic **prcm_irq_chips;

/*
 * prcm_irq_setup: the PRCM IRQ parameters for the hardware the code
 * is currently running on.  Defined and passed by initialization code
 * that calls omap_prcm_register_chain_handler().
 */
static struct omap_prcm_irq_setup *prcm_irq_setup;

/* prm_base: base virtual address of the PRM IP block */
struct omap_domain_base prm_base;

u16 prm_features;

/*
 * Platforms that implement different reboot modes can store the requested
 * mode here.
 */
enum reboot_mode prm_reboot_mode;

/*
 * prm_ll_data: function pointers to SoC-specific implementations of
 * common PRM functions
 */
static struct prm_ll_data null_prm_ll_data;
static struct prm_ll_data *prm_ll_data = &null_prm_ll_data;

/* Private functions */

/*
 * Move priority events from events to priority_events array
 */
static void omap_prcm_events_filter_priority(unsigned long *events,
        unsigned long *priority_events)
{
        int i;

        for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
                priority_events[i] =
                        events[i] & prcm_irq_setup->priority_mask[i];
                events[i] ^= priority_events[i];
        }
}

/*
 * PRCM Interrupt Handler
 *
 * This is a common handler for the OMAP PRCM interrupts. Pending
 * interrupts are detected by a call to prcm_pending_events and
 * dispatched accordingly. Clearing of the wakeup events should be
 * done by the SoC specific individual handlers.
 */
static void omap_prcm_irq_handler(struct irq_desc *desc)
{
        unsigned long pending[OMAP_PRCM_MAX_NR_PENDING_REG];
        unsigned long priority_pending[OMAP_PRCM_MAX_NR_PENDING_REG];
        struct irq_chip *chip = irq_desc_get_chip(desc);
        unsigned int virtirq;
        int nr_irq = prcm_irq_setup->nr_regs * 32;

        /*
         * If we are suspended, mask all interrupts from PRCM level,
         * this does not ack them, and they will be pending until we
         * re-enable the interrupts, at which point the
         * omap_prcm_irq_handler will be executed again.  The
         * _save_and_clear_irqen() function must ensure that the PRM
         * write to disable all IRQs has reached the PRM before
         * returning, or spurious PRCM interrupts may occur during
         * suspend.
         */
        if (prcm_irq_setup->suspended) {
                prcm_irq_setup->save_and_clear_irqen(prcm_irq_setup->saved_mask);
                prcm_irq_setup->suspend_save_flag = true;
        }

        /*
         * Loop until all pending irqs are handled, since
         * generic_handle_irq() can cause new irqs to come
         */
        while (!prcm_irq_setup->suspended) {
                prcm_irq_setup->read_pending_irqs(pending);

                /* No bit set, then all IRQs are handled */
                if (find_first_bit(pending, nr_irq) >= nr_irq)
                        break;

                omap_prcm_events_filter_priority(pending, priority_pending);

                /*
                 * Loop on all currently pending irqs so that new irqs
                 * cannot starve previously pending irqs
                 */

                /* Serve priority events first */
                for_each_set_bit(virtirq, priority_pending, nr_irq)
                        generic_handle_irq(prcm_irq_setup->base_irq + virtirq);

                /* Serve normal events next */
                for_each_set_bit(virtirq, pending, nr_irq)
                        generic_handle_irq(prcm_irq_setup->base_irq + virtirq);
        }
        if (chip->irq_ack)
                chip->irq_ack(&desc->irq_data);
        if (chip->irq_eoi)
                chip->irq_eoi(&desc->irq_data);
        chip->irq_unmask(&desc->irq_data);

        prcm_irq_setup->ocp_barrier(); /* avoid spurious IRQs */
}

/* Public functions */

/**
 * omap_prcm_event_to_irq - given a PRCM event name, returns the
 * corresponding IRQ on which the handler should be registered
 * @name: name of the PRCM interrupt bit to look up - see struct omap_prcm_irq
 *
 * Returns the Linux internal IRQ ID corresponding to @name upon success,
 * or -ENOENT upon failure.
 */
int omap_prcm_event_to_irq(const char *name)
{
        int i;

        if (!prcm_irq_setup || !name)
                return -ENOENT;

        for (i = 0; i < prcm_irq_setup->nr_irqs; i++)
                if (!strcmp(prcm_irq_setup->irqs[i].name, name))
                        return prcm_irq_setup->base_irq +
                                prcm_irq_setup->irqs[i].offset;

        return -ENOENT;
}

/**
 * omap_prcm_irq_cleanup - reverses memory allocated and other steps
 * done by omap_prcm_register_chain_handler()
 *
 * No return value.
 */
static void omap_prcm_irq_cleanup(void)
{
        unsigned int irq;
        int i;

        if (!prcm_irq_setup) {
                pr_err("PRCM: IRQ handler not initialized; cannot cleanup\n");
                return;
        }

        if (prcm_irq_chips) {
                for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
                        if (prcm_irq_chips[i])
                                irq_remove_generic_chip(prcm_irq_chips[i],
                                        0xffffffff, 0, 0);
                        prcm_irq_chips[i] = NULL;
                }
                kfree(prcm_irq_chips);
                prcm_irq_chips = NULL;
        }

        kfree(prcm_irq_setup->saved_mask);
        prcm_irq_setup->saved_mask = NULL;

        kfree(prcm_irq_setup->priority_mask);
        prcm_irq_setup->priority_mask = NULL;

        irq = prcm_irq_setup->irq;
        irq_set_chained_handler(irq, NULL);

        if (prcm_irq_setup->base_irq > 0)
                irq_free_descs(prcm_irq_setup->base_irq,
                        prcm_irq_setup->nr_regs * 32);
        prcm_irq_setup->base_irq = 0;
}

void omap_prcm_irq_prepare(void)
{
        prcm_irq_setup->suspended = true;
}

void omap_prcm_irq_complete(void)
{
        prcm_irq_setup->suspended = false;

        /* If we have not saved the masks, do not attempt to restore */
        if (!prcm_irq_setup->suspend_save_flag)
                return;

        prcm_irq_setup->suspend_save_flag = false;

        /*
         * Re-enable all masked PRCM irq sources, this causes the PRCM
         * interrupt to fire immediately if the events were masked
         * previously in the chain handler
         */
        prcm_irq_setup->restore_irqen(prcm_irq_setup->saved_mask);
}

/**
 * omap_prcm_register_chain_handler - initializes the prcm chained interrupt
 * handler based on provided parameters
 * @irq_setup: hardware data about the underlying PRM/PRCM
 *
 * Set up the PRCM chained interrupt handler on the PRCM IRQ.  Sets up
 * one generic IRQ chip per PRM interrupt status/enable register pair.
 * Returns 0 upon success, -EINVAL if called twice or if invalid
 * arguments are passed, or -ENOMEM on any other error.
 */
int omap_prcm_register_chain_handler(struct omap_prcm_irq_setup *irq_setup)
{
        int nr_regs;
        u32 mask[OMAP_PRCM_MAX_NR_PENDING_REG];
        int offset, i, irq;
        struct irq_chip_generic *gc;
        struct irq_chip_type *ct;

        if (!irq_setup)
                return -EINVAL;

        nr_regs = irq_setup->nr_regs;

        if (prcm_irq_setup) {
                pr_err("PRCM: already initialized; won't reinitialize\n");
                return -EINVAL;
        }

        if (nr_regs > OMAP_PRCM_MAX_NR_PENDING_REG) {
                pr_err("PRCM: nr_regs too large\n");
                return -EINVAL;
        }

        prcm_irq_setup = irq_setup;

        prcm_irq_chips = kcalloc(nr_regs, sizeof(void *), GFP_KERNEL);
        prcm_irq_setup->saved_mask = kcalloc(nr_regs, sizeof(u32),
                                             GFP_KERNEL);
        prcm_irq_setup->priority_mask = kcalloc(nr_regs, sizeof(u32),
                                                GFP_KERNEL);

        if (!prcm_irq_chips || !prcm_irq_setup->saved_mask ||
            !prcm_irq_setup->priority_mask)
                goto err;

        memset(mask, 0, sizeof(mask));

        for (i = 0; i < irq_setup->nr_irqs; i++) {
                offset = irq_setup->irqs[i].offset;
                mask[offset >> 5] |= 1 << (offset & 0x1f);
                if (irq_setup->irqs[i].priority)
                        irq_setup->priority_mask[offset >> 5] |=
                                1 << (offset & 0x1f);
        }

        irq = irq_setup->irq;
        irq_set_chained_handler(irq, omap_prcm_irq_handler);

        irq_setup->base_irq = irq_alloc_descs(-1, 0, irq_setup->nr_regs * 32,
                0);

        if (irq_setup->base_irq < 0) {
                pr_err("PRCM: failed to allocate irq descs: %d\n",
                        irq_setup->base_irq);
                goto err;
        }

        for (i = 0; i < irq_setup->nr_regs; i++) {
                gc = irq_alloc_generic_chip("PRCM", 1,
                        irq_setup->base_irq + i * 32, prm_base.va,
                        handle_level_irq);

                if (!gc) {
                        pr_err("PRCM: failed to allocate generic chip\n");
                        goto err;
                }
                ct = gc->chip_types;
                ct->chip.irq_ack = irq_gc_ack_set_bit;
                ct->chip.irq_mask = irq_gc_mask_clr_bit;
                ct->chip.irq_unmask = irq_gc_mask_set_bit;

                ct->regs.ack = irq_setup->ack + i * 4;
                ct->regs.mask = irq_setup->mask + i * 4;

                irq_setup_generic_chip(gc, mask[i], 0, IRQ_NOREQUEST, 0);
                prcm_irq_chips[i] = gc;
        }

        irq = omap_prcm_event_to_irq("io");
        omap_pcs_legacy_init(irq, irq_setup->reconfigure_io_chain);

        return 0;

err:
        omap_prcm_irq_cleanup();
        return -ENOMEM;
}

/**
 * prm_was_any_context_lost_old - was device context lost? (old API)
 * @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.  XXX Deprecated;
 * callers need to use a less-SoC-dependent way to identify hardware
 * IP blocks.
 */
bool prm_was_any_context_lost_old(u8 part, s16 inst, u16 idx)
{
        bool ret = true;

        if (prm_ll_data->was_any_context_lost_old)
                ret = prm_ll_data->was_any_context_lost_old(part, inst, idx);
        else
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);

        return ret;
}

/**
 * prm_clear_context_loss_flags_old - clear context loss flags (old API)
 * @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 Deprecated; callers
 * need to use a less-SoC-dependent way to identify hardware IP
 * blocks.
 */
void prm_clear_context_loss_flags_old(u8 part, s16 inst, u16 idx)
{
        if (prm_ll_data->clear_context_loss_flags_old)
                prm_ll_data->clear_context_loss_flags_old(part, inst, idx);
        else
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
}

/**
 * omap_prm_assert_hardreset - assert hardreset for an IP block
 * @shift: register bit shift corresponding to the reset line
 * @part: PRM partition
 * @prm_mod: PRM submodule base or instance offset
 * @offset: register offset
 *
 * Asserts a hardware reset line for an IP block.
 */
int omap_prm_assert_hardreset(u8 shift, u8 part, s16 prm_mod, u16 offset)
{
        if (!prm_ll_data->assert_hardreset) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return -EINVAL;
        }

        return prm_ll_data->assert_hardreset(shift, part, prm_mod, offset);
}

/**
 * omap_prm_deassert_hardreset - deassert hardreset for an IP block
 * @shift: register bit shift corresponding to the reset line
 * @st_shift: reset status bit shift corresponding to the reset line
 * @part: PRM partition
 * @prm_mod: PRM submodule base or instance offset
 * @offset: register offset
 * @st_offset: status register offset
 *
 * Deasserts a hardware reset line for an IP block.
 */
int omap_prm_deassert_hardreset(u8 shift, u8 st_shift, u8 part, s16 prm_mod,
                                u16 offset, u16 st_offset)
{
        if (!prm_ll_data->deassert_hardreset) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return -EINVAL;
        }

        return prm_ll_data->deassert_hardreset(shift, st_shift, part, prm_mod,
                                               offset, st_offset);
}

/**
 * omap_prm_is_hardreset_asserted - check the hardreset status for an IP block
 * @shift: register bit shift corresponding to the reset line
 * @part: PRM partition
 * @prm_mod: PRM submodule base or instance offset
 * @offset: register offset
 *
 * Checks if a hardware reset line for an IP block is enabled or not.
 */
int omap_prm_is_hardreset_asserted(u8 shift, u8 part, s16 prm_mod, u16 offset)
{
        if (!prm_ll_data->is_hardreset_asserted) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return -EINVAL;
        }

        return prm_ll_data->is_hardreset_asserted(shift, part, prm_mod, offset);
}

/**
 * omap_prm_reset_system - trigger global SW reset
 *
 * Triggers SoC specific global warm reset to reboot the device.
 */
void omap_prm_reset_system(void)
{
        if (!prm_ll_data->reset_system) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return;
        }

        prm_ll_data->reset_system();

        while (1) {
                cpu_relax();
                wfe();
        }
}

/**
 * omap_prm_clear_mod_irqs - clear wake-up events from PRCM interrupt
 * @module: PRM module to clear wakeups from
 * @regs: register to clear
 * @wkst_mask: wkst bits to clear
 *
 * Clears any wakeup events for the module and register set defined.
 * Uses SoC specific implementation to do the actual wakeup status
 * clearing.
 */
int omap_prm_clear_mod_irqs(s16 module, u8 regs, u32 wkst_mask)
{
        if (!prm_ll_data->clear_mod_irqs) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return -EINVAL;
        }

        return prm_ll_data->clear_mod_irqs(module, regs, wkst_mask);
}

/**
 * omap_prm_vp_check_txdone - check voltage processor TX done status
 * @vp_id: unique VP instance ID
 *
 * Checks if voltage processor transmission has been completed.
 * Returns non-zero if a transmission has completed, 0 otherwise.
 */
u32 omap_prm_vp_check_txdone(u8 vp_id)
{
        if (!prm_ll_data->vp_check_txdone) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return 0;
        }

        return prm_ll_data->vp_check_txdone(vp_id);
}

/**
 * omap_prm_vp_clear_txdone - clears voltage processor TX done status
 * @vp_id: unique VP instance ID
 *
 * Clears the status bit for completed voltage processor transmission
 * returned by prm_vp_check_txdone.
 */
void omap_prm_vp_clear_txdone(u8 vp_id)
{
        if (!prm_ll_data->vp_clear_txdone) {
                WARN_ONCE(1, "prm: %s: no mapping function defined\n",
                          __func__);
                return;
        }

        prm_ll_data->vp_clear_txdone(vp_id);
}

/**
 * prm_register - register per-SoC low-level data with the PRM
 * @pld: low-level per-SoC OMAP PRM data & function pointers to register
 *
 * Register per-SoC low-level OMAP PRM data and function pointers with
 * the OMAP PRM common interface.  The caller must keep the data
 * pointed to by @pld valid until it calls prm_unregister() and
 * it returns successfully.  Returns 0 upon success, -EINVAL if @pld
 * is NULL, or -EEXIST if prm_register() has already been called
 * without an intervening prm_unregister().
 */
int prm_register(struct prm_ll_data *pld)
{
        if (!pld)
                return -EINVAL;

        if (prm_ll_data != &null_prm_ll_data)
                return -EEXIST;

        prm_ll_data = pld;

        return 0;
}

/**
 * prm_unregister - unregister per-SoC low-level data & function pointers
 * @pld: low-level per-SoC OMAP PRM data & function pointers to unregister
 *
 * Unregister per-SoC low-level OMAP PRM data and function pointers
 * that were previously registered with prm_register().  The
 * caller may not destroy any of the data pointed to by @pld until
 * this function returns successfully.  Returns 0 upon success, or
 * -EINVAL if @pld is NULL or if @pld does not match the struct
 * prm_ll_data * previously registered by prm_register().
 */
int prm_unregister(struct prm_ll_data *pld)
{
        if (!pld || prm_ll_data != pld)
                return -EINVAL;

        prm_ll_data = &null_prm_ll_data;

        return 0;
}

#ifdef CONFIG_ARCH_OMAP2
static struct omap_prcm_init_data omap2_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap2xxx_prm_init,
};
#endif

#ifdef CONFIG_ARCH_OMAP3
static struct omap_prcm_init_data omap3_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap3xxx_prm_init,

        /*
         * IVA2 offset is a negative value, must offset the prm_base
         * address by this to get it to positive
         */
        .offset = -OMAP3430_IVA2_MOD,
};
#endif

#if defined(CONFIG_SOC_AM33XX) || defined(CONFIG_SOC_TI81XX)
static struct omap_prcm_init_data am3_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = am33xx_prm_init,
};
#endif

#ifdef CONFIG_SOC_TI81XX
static struct omap_prcm_init_data dm814_pllss_data __initdata = {
        .index = TI_CLKM_PLLSS,
        .init = am33xx_prm_init,
};
#endif

#ifdef CONFIG_ARCH_OMAP4
static struct omap_prcm_init_data omap4_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap44xx_prm_init,
        .device_inst_offset = OMAP4430_PRM_DEVICE_INST,
        .flags = PRM_HAS_IO_WAKEUP | PRM_HAS_VOLTAGE,
};
#endif

#ifdef CONFIG_SOC_OMAP5
static struct omap_prcm_init_data omap5_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap44xx_prm_init,
        .device_inst_offset = OMAP54XX_PRM_DEVICE_INST,
        .flags = PRM_HAS_IO_WAKEUP | PRM_HAS_VOLTAGE,
};
#endif

#ifdef CONFIG_SOC_DRA7XX
static struct omap_prcm_init_data dra7_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap44xx_prm_init,
        .device_inst_offset = DRA7XX_PRM_DEVICE_INST,
        .flags = PRM_HAS_IO_WAKEUP,
};
#endif

#ifdef CONFIG_SOC_AM43XX
static struct omap_prcm_init_data am4_prm_data __initdata = {
        .index = TI_CLKM_PRM,
        .init = omap44xx_prm_init,
        .device_inst_offset = AM43XX_PRM_DEVICE_INST,
        .flags = PRM_HAS_IO_WAKEUP,
};
#endif

#if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5)
static struct omap_prcm_init_data scrm_data __initdata = {
        .index = TI_CLKM_SCRM,
};
#endif

static const struct of_device_id omap_prcm_dt_match_table[] __initconst = {
#ifdef CONFIG_SOC_AM33XX
        { .compatible = "ti,am3-prcm", .data = &am3_prm_data },
#endif
#ifdef CONFIG_SOC_AM43XX
        { .compatible = "ti,am4-prcm", .data = &am4_prm_data },
#endif
#ifdef CONFIG_SOC_TI81XX
        { .compatible = "ti,dm814-prcm", .data = &am3_prm_data },
        { .compatible = "ti,dm814-pllss", .data = &dm814_pllss_data },
        { .compatible = "ti,dm816-prcm", .data = &am3_prm_data },
#endif
#ifdef CONFIG_ARCH_OMAP2
        { .compatible = "ti,omap2-prcm", .data = &omap2_prm_data },
#endif
#ifdef CONFIG_ARCH_OMAP3
        { .compatible = "ti,omap3-prm", .data = &omap3_prm_data },
#endif
#ifdef CONFIG_ARCH_OMAP4
        { .compatible = "ti,omap4-prm", .data = &omap4_prm_data },
        { .compatible = "ti,omap4-scrm", .data = &scrm_data },
#endif
#ifdef CONFIG_SOC_OMAP5
        { .compatible = "ti,omap5-prm", .data = &omap5_prm_data },
        { .compatible = "ti,omap5-scrm", .data = &scrm_data },
#endif
#ifdef CONFIG_SOC_DRA7XX
        { .compatible = "ti,dra7-prm", .data = &dra7_prm_data },
#endif
        { }
};

/**
 * omap2_prm_base_init - initialize iomappings for the PRM driver
 *
 * Detects and initializes the iomappings for the PRM driver, based
 * on the DT data. Returns 0 in success, negative error value
 * otherwise.
 */
static int __init omap2_prm_base_init(void)
{
        struct device_node *np;
        const struct of_device_id *match;
        struct omap_prcm_init_data *data;
        struct resource res;
        int ret;

        for_each_matching_node_and_match(np, omap_prcm_dt_match_table, &match) {
                data = (struct omap_prcm_init_data *)match->data;

                ret = of_address_to_resource(np, 0, &res);
                if (ret) {
                        of_node_put(np);
                        return ret;
                }

                data->mem = ioremap(res.start, resource_size(&res));

                if (data->index == TI_CLKM_PRM) {
                        prm_base.va = data->mem + data->offset;
                        prm_base.pa = res.start + data->offset;
                }

                data->np = np;

                if (data->init)
                        data->init(data);
        }

        return 0;
}

int __init omap2_prcm_base_init(void)
{
        int ret;

        ret = omap2_prm_base_init();
        if (ret)
                return ret;

        return omap2_cm_base_init();
}

/**
 * omap_prcm_init - low level init for the PRCM drivers
 *
 * Initializes the low level clock infrastructure for PRCM drivers.
 * Returns 0 in success, negative error value in failure.
 */
int __init omap_prcm_init(void)
{
        struct device_node *np;
        const struct of_device_id *match;
        const struct omap_prcm_init_data *data;
        int ret;

        for_each_matching_node_and_match(np, omap_prcm_dt_match_table, &match) {
                data = match->data;

                ret = omap2_clk_provider_init(np, data->index, NULL, data->mem);
                if (ret) {
                        of_node_put(np);
                        return ret;
                }
        }

        omap_cm_init();

        return 0;
}

static int __init prm_late_init(void)
{
        if (prm_ll_data->late_init)
                return prm_ll_data->late_init();
        return 0;
}
subsys_initcall(prm_late_init);