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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /*
  * SuperH clock framework
  *
  *  Copyright (C) 2005 - 2010  Paul Mundt
  *
  * This clock framework is derived from the OMAP version by:
  *
  *  Copyright (C) 2004 - 2008 Nokia Corporation
  *  Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
  *
  *  Modified for omap shared clock framework by Tony Lindgren <tony@atomide.com>
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */
 #define pr_fmt(fmt) "clock: " fmt
 
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/list.h>
 #include <linux/syscore_ops.h>
 #include <linux/seq_file.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/cpufreq.h>
 #include <linux/clk.h>
 #include <linux/sh_clk.h>
 
 static LIST_HEAD(clock_list);
 static DEFINE_SPINLOCK(clock_lock);
 static DEFINE_MUTEX(clock_list_sem);
 
 /* clock disable operations are not passed on to hardware during boot */
 static int allow_disable;
 
 void clk_rate_table_build(struct clk *clk,
               struct cpufreq_frequency_table *freq_table,
               int nr_freqs,
               struct clk_div_mult_table *src_table,
               unsigned long *bitmap)
 {
     unsigned long mult, div;
     unsigned long freq;
     int i;
 
     clk->nr_freqs = nr_freqs;
 
     for (i = 0; i < nr_freqs; i++) {
         div = 1;
         mult = 1;
 
         if (src_table->divisors && i < src_table->nr_divisors)
             div = src_table->divisors[i];
 
         if (src_table->multipliers && i < src_table->nr_multipliers)
             mult = src_table->multipliers[i];
 
         if (!div || !mult || (bitmap && !test_bit(i, bitmap)))
             freq = CPUFREQ_ENTRY_INVALID;
         else
             freq = clk->parent->rate * mult / div;
 
         freq_table[i].driver_data = i;
         freq_table[i].frequency = freq;
     }
 
     /* Termination entry */
     freq_table[i].driver_data = i;
     freq_table[i].frequency = CPUFREQ_TABLE_END;
 }
 
 struct clk_rate_round_data;
 
 struct clk_rate_round_data {
     unsigned long rate;
     unsigned int min, max;
     long (*func)(unsigned int, struct clk_rate_round_data *);
     void *arg;
 };
 
 #define for_each_frequency(pos, r, freq)            \
     for (pos = r->min, freq = r->func(pos, r);      \
          pos <= r->max; pos++, freq = r->func(pos, r))  \
         if (unlikely(freq == 0))            \
             ;                   \
         else
 
 static long clk_rate_round_helper(struct clk_rate_round_data *rounder)
 {
     unsigned long rate_error, rate_error_prev = ~0UL;
     unsigned long highest, lowest, freq;
     long rate_best_fit = -ENOENT;
     int i;
 
     highest = 0;
     lowest = ~0UL;
 
     for_each_frequency(i, rounder, freq) {
         if (freq > highest)
             highest = freq;
         if (freq < lowest)
             lowest = freq;
 
         rate_error = abs(freq - rounder->rate);
         if (rate_error < rate_error_prev) {
             rate_best_fit = freq;
             rate_error_prev = rate_error;
         }
 
         if (rate_error == 0)
             break;
     }
 
     if (rounder->rate >= highest)
         rate_best_fit = highest;
     if (rounder->rate <= lowest)
         rate_best_fit = lowest;
 
     return rate_best_fit;
 }
 
 static long clk_rate_table_iter(unsigned int pos,
                 struct clk_rate_round_data *rounder)
 {
     struct cpufreq_frequency_table *freq_table = rounder->arg;
     unsigned long freq = freq_table[pos].frequency;
 
     if (freq == CPUFREQ_ENTRY_INVALID)
         freq = 0;
 
     return freq;
 }
 
 long clk_rate_table_round(struct clk *clk,
               struct cpufreq_frequency_table *freq_table,
               unsigned long rate)
 {
     struct clk_rate_round_data table_round = {
         .min    = 0,
         .max    = clk->nr_freqs - 1,
         .func   = clk_rate_table_iter,
         .arg    = freq_table,
         .rate   = rate,
     };
 
     if (clk->nr_freqs < 1)
         return -ENOSYS;
 
     return clk_rate_round_helper(&table_round);
 }
 
 static long clk_rate_div_range_iter(unsigned int pos,
                     struct clk_rate_round_data *rounder)
 {
     return clk_get_rate(rounder->arg) / pos;
 }
 
 long clk_rate_div_range_round(struct clk *clk, unsigned int div_min,
                   unsigned int div_max, unsigned long rate)
 {
     struct clk_rate_round_data div_range_round = {
         .min    = div_min,
         .max    = div_max,
         .func   = clk_rate_div_range_iter,
         .arg    = clk_get_parent(clk),
         .rate   = rate,
     };
 
     return clk_rate_round_helper(&div_range_round);
 }
 
 static long clk_rate_mult_range_iter(unsigned int pos,
                       struct clk_rate_round_data *rounder)
 {
     return clk_get_rate(rounder->arg) * pos;
 }
 
 long clk_rate_mult_range_round(struct clk *clk, unsigned int mult_min,
                    unsigned int mult_max, unsigned long rate)
 {
     struct clk_rate_round_data mult_range_round = {
         .min    = mult_min,
         .max    = mult_max,
         .func   = clk_rate_mult_range_iter,
         .arg    = clk_get_parent(clk),
         .rate   = rate,
     };
 
     return clk_rate_round_helper(&mult_range_round);
 }
 
 int clk_rate_table_find(struct clk *clk,
             struct cpufreq_frequency_table *freq_table,
             unsigned long rate)
 {
     struct cpufreq_frequency_table *pos;
     int idx;
 
     cpufreq_for_each_valid_entry_idx(pos, freq_table, idx)
         if (pos->frequency == rate)
             return idx;
 
     return -ENOENT;
 }
 
 /* Used for clocks that always have same value as the parent clock */
 unsigned long followparent_recalc(struct clk *clk)
 {
     return clk->parent ? clk->parent->rate : 0;
 }
 
 int clk_reparent(struct clk *child, struct clk *parent)
 {
     list_del_init(&child->sibling);
     if (parent)
         list_add(&child->sibling, &parent->children);
     child->parent = parent;
 
     return 0;
 }
 
 /* Propagate rate to children */
 void propagate_rate(struct clk *tclk)
 {
     struct clk *clkp;
 
     list_for_each_entry(clkp, &tclk->children, sibling) {
         if (clkp->ops && clkp->ops->recalc)
             clkp->rate = clkp->ops->recalc(clkp);
 
         propagate_rate(clkp);
     }
 }
 
 static void __clk_disable(struct clk *clk)
 {
     if (WARN(!clk->usecount, "Trying to disable clock %p with 0 usecount\n",
          clk))
         return;
 
     if (!(--clk->usecount)) {
         if (likely(allow_disable && clk->ops && clk->ops->disable))
             clk->ops->disable(clk);
         if (likely(clk->parent))
             __clk_disable(clk->parent);
     }
 }
 
 void clk_disable(struct clk *clk)
 {
     unsigned long flags;
 
     if (!clk)
         return;
 
     spin_lock_irqsave(&clock_lock, flags);
     __clk_disable(clk);
     spin_unlock_irqrestore(&clock_lock, flags);
 }
 EXPORT_SYMBOL_GPL(clk_disable);
 
 static int __clk_enable(struct clk *clk)
 {
     int ret = 0;
 
     if (clk->usecount++ == 0) {
         if (clk->parent) {
             ret = __clk_enable(clk->parent);
             if (unlikely(ret))
                 goto err;
         }
 
         if (clk->ops && clk->ops->enable) {
             ret = clk->ops->enable(clk);
             if (ret) {
                 if (clk->parent)
                     __clk_disable(clk->parent);
                 goto err;
             }
         }
     }
 
     return ret;
 err:
     clk->usecount--;
     return ret;
 }
 
 int clk_enable(struct clk *clk)
 {
     unsigned long flags;
     int ret;
 
     if (!clk)
         return -EINVAL;
 
     spin_lock_irqsave(&clock_lock, flags);
     ret = __clk_enable(clk);
     spin_unlock_irqrestore(&clock_lock, flags);
 
     return ret;
 }
 EXPORT_SYMBOL_GPL(clk_enable);
 
 static LIST_HEAD(root_clks);
 
 /**
  * recalculate_root_clocks - recalculate and propagate all root clocks
  *
  * Recalculates all root clocks (clocks with no parent), which if the
  * clock's .recalc is set correctly, should also propagate their rates.
  * Called at init.
  */
 void recalculate_root_clocks(void)
 {
     struct clk *clkp;
 
     list_for_each_entry(clkp, &root_clks, sibling) {
         if (clkp->ops && clkp->ops->recalc)
             clkp->rate = clkp->ops->recalc(clkp);
         propagate_rate(clkp);
     }
 }
 
 static struct clk_mapping dummy_mapping;
 
 static struct clk *lookup_root_clock(struct clk *clk)
 {
     while (clk->parent)
         clk = clk->parent;
 
     return clk;
 }
 
 static int clk_establish_mapping(struct clk *clk)
 {
     struct clk_mapping *mapping = clk->mapping;
 
     /*
      * Propagate mappings.
      */
     if (!mapping) {
         struct clk *clkp;
 
         /*
          * dummy mapping for root clocks with no specified ranges
          */
         if (!clk->parent) {
             clk->mapping = &dummy_mapping;
             goto out;
         }
 
         /*
          * If we're on a child clock and it provides no mapping of its
          * own, inherit the mapping from its root clock.
          */
         clkp = lookup_root_clock(clk);
         mapping = clkp->mapping;
         BUG_ON(!mapping);
     }
 
     /*
      * Establish initial mapping.
      */
     if (!mapping->base && mapping->phys) {
         kref_init(&mapping->ref);
 
         mapping->base = ioremap(mapping->phys, mapping->len);
         if (unlikely(!mapping->base))
             return -ENXIO;
     } else if (mapping->base) {
         /*
          * Bump the refcount for an existing mapping
          */
         kref_get(&mapping->ref);
     }
 
     clk->mapping = mapping;
 out:
     clk->mapped_reg = clk->mapping->base;
     clk->mapped_reg += (phys_addr_t)clk->enable_reg - clk->mapping->phys;
     return 0;
 }
 
 static void clk_destroy_mapping(struct kref *kref)
 {
     struct clk_mapping *mapping;
 
     mapping = container_of(kref, struct clk_mapping, ref);
 
     iounmap(mapping->base);
 }
 
 static void clk_teardown_mapping(struct clk *clk)
 {
     struct clk_mapping *mapping = clk->mapping;
 
     /* Nothing to do */
     if (mapping == &dummy_mapping)
         goto out;
 
     kref_put(&mapping->ref, clk_destroy_mapping);
     clk->mapping = NULL;
 out:
     clk->mapped_reg = NULL;
 }
 
 int clk_register(struct clk *clk)
 {
     int ret;
 
     if (IS_ERR_OR_NULL(clk))
         return -EINVAL;
 
     /*
      * trap out already registered clocks
      */
     if (clk->node.next || clk->node.prev)
         return 0;
 
     mutex_lock(&clock_list_sem);
 
     INIT_LIST_HEAD(&clk->children);
     clk->usecount = 0;
 
     ret = clk_establish_mapping(clk);
     if (unlikely(ret))
         goto out_unlock;
 
     if (clk->parent)
         list_add(&clk->sibling, &clk->parent->children);
     else
         list_add(&clk->sibling, &root_clks);
 
     list_add(&clk->node, &clock_list);
 
 #ifdef CONFIG_SH_CLK_CPG_LEGACY
     if (clk->ops && clk->ops->init)
         clk->ops->init(clk);
 #endif
 
 out_unlock:
     mutex_unlock(&clock_list_sem);
 
     return ret;
 }
 EXPORT_SYMBOL_GPL(clk_register);
 
 void clk_unregister(struct clk *clk)
 {
     mutex_lock(&clock_list_sem);
     list_del(&clk->sibling);
     list_del(&clk->node);
     clk_teardown_mapping(clk);
     mutex_unlock(&clock_list_sem);
 }
 EXPORT_SYMBOL_GPL(clk_unregister);
 
 void clk_enable_init_clocks(void)
 {
     struct clk *clkp;
 
     list_for_each_entry(clkp, &clock_list, node)
         if (clkp->flags & CLK_ENABLE_ON_INIT)
             clk_enable(clkp);
 }
 
 unsigned long clk_get_rate(struct clk *clk)
 {
     if (!clk)
         return 0;
 
     return clk->rate;
 }
 EXPORT_SYMBOL_GPL(clk_get_rate);
 
 int clk_set_rate(struct clk *clk, unsigned long rate)
 {
     int ret = -EOPNOTSUPP;
     unsigned long flags;
 
     if (!clk)
         return 0;
 
     spin_lock_irqsave(&clock_lock, flags);
 
     if (likely(clk->ops && clk->ops->set_rate)) {
         ret = clk->ops->set_rate(clk, rate);
         if (ret != 0)
             goto out_unlock;
     } else {
         clk->rate = rate;
         ret = 0;
     }
 
     if (clk->ops && clk->ops->recalc)
         clk->rate = clk->ops->recalc(clk);
 
     propagate_rate(clk);
 
 out_unlock:
     spin_unlock_irqrestore(&clock_lock, flags);
 
     return ret;
 }
 EXPORT_SYMBOL_GPL(clk_set_rate);
 
 int clk_set_parent(struct clk *clk, struct clk *parent)
 {
     unsigned long flags;
     int ret = -EINVAL;
 
     if (!parent || !clk)
         return ret;
     if (clk->parent == parent)
         return 0;
 
     spin_lock_irqsave(&clock_lock, flags);
     if (clk->usecount == 0) {
         if (clk->ops->set_parent)
             ret = clk->ops->set_parent(clk, parent);
         else
             ret = clk_reparent(clk, parent);
 
         if (ret == 0) {
             if (clk->ops->recalc)
                 clk->rate = clk->ops->recalc(clk);
             pr_debug("set parent of %p to %p (new rate %ld)\n",
                  clk, clk->parent, clk->rate);
             propagate_rate(clk);
         }
     } else
         ret = -EBUSY;
     spin_unlock_irqrestore(&clock_lock, flags);
 
     return ret;
 }
 EXPORT_SYMBOL_GPL(clk_set_parent);
 
 struct clk *clk_get_parent(struct clk *clk)
 {
     if (!clk)
         return NULL;
 
     return clk->parent;
 }
 EXPORT_SYMBOL_GPL(clk_get_parent);
 
 long clk_round_rate(struct clk *clk, unsigned long rate)
 {
     if (!clk)
         return 0;
 
     if (likely(clk->ops && clk->ops->round_rate)) {
         unsigned long flags, rounded;
 
         spin_lock_irqsave(&clock_lock, flags);
         rounded = clk->ops->round_rate(clk, rate);
         spin_unlock_irqrestore(&clock_lock, flags);
 
         return rounded;
     }
 
     return clk_get_rate(clk);
 }
 EXPORT_SYMBOL_GPL(clk_round_rate);
 
 #ifdef CONFIG_PM
 static void clks_core_resume(void)
 {
     struct clk *clkp;
 
     list_for_each_entry(clkp, &clock_list, node) {
         if (likely(clkp->usecount && clkp->ops)) {
             unsigned long rate = clkp->rate;
 
             if (likely(clkp->ops->set_parent))
                 clkp->ops->set_parent(clkp,
                     clkp->parent);
             if (likely(clkp->ops->set_rate))
                 clkp->ops->set_rate(clkp, rate);
             else if (likely(clkp->ops->recalc))
                 clkp->rate = clkp->ops->recalc(clkp);
         }
     }
 }
 
 static struct syscore_ops clks_syscore_ops = {
     .resume = clks_core_resume,
 };
 
 static int __init clk_syscore_init(void)
 {
     register_syscore_ops(&clks_syscore_ops);
 
     return 0;
 }
 subsys_initcall(clk_syscore_init);
 #endif
 
 static int __init clk_late_init(void)
 {
     unsigned long flags;
     struct clk *clk;
 
     /* disable all clocks with zero use count */
     mutex_lock(&clock_list_sem);
     spin_lock_irqsave(&clock_lock, flags);
 
     list_for_each_entry(clk, &clock_list, node)
         if (!clk->usecount && clk->ops && clk->ops->disable)
             clk->ops->disable(clk);
 
     /* from now on allow clock disable operations */
     allow_disable = 1;
 
     spin_unlock_irqrestore(&clock_lock, flags);
     mutex_unlock(&clock_list_sem);
     return 0;
 }
 late_initcall(clk_late_init);

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