arch/arm/mach-mmp/clock.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/arch/arm/mach-mmp/clock.c
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/kernel.h>
   8 #include <linux/list.h>
   9 #include <linux/spinlock.h>
  10 #include <linux/clk.h>
  11 #include <linux/io.h>
  12
  13 #include "regs-apbc.h"
  14 #include "clock.h"
  15
  16 static void apbc_clk_enable(struct clk *clk)
  17 {
  18         uint32_t clk_rst;
  19
  20         clk_rst = APBC_APBCLK | APBC_FNCLK | APBC_FNCLKSEL(clk->fnclksel);
  21         __raw_writel(clk_rst, clk->clk_rst);
  22 }
  23
  24 static void apbc_clk_disable(struct clk *clk)
  25 {
  26         __raw_writel(0, clk->clk_rst);
  27 }
  28
  29 struct clkops apbc_clk_ops = {
  30         .enable         = apbc_clk_enable,
  31         .disable        = apbc_clk_disable,
  32 };
  33
  34 static void apmu_clk_enable(struct clk *clk)
  35 {
  36         __raw_writel(clk->enable_val, clk->clk_rst);
  37 }
  38
  39 static void apmu_clk_disable(struct clk *clk)
  40 {
  41         __raw_writel(0, clk->clk_rst);
  42 }
  43
  44 struct clkops apmu_clk_ops = {
  45         .enable         = apmu_clk_enable,
  46         .disable        = apmu_clk_disable,
  47 };
  48
  49 static DEFINE_SPINLOCK(clocks_lock);
  50
  51 int clk_enable(struct clk *clk)
  52 {
  53         unsigned long flags;
  54
  55         spin_lock_irqsave(&clocks_lock, flags);
  56         if (clk->enabled++ == 0)
  57                 clk->ops->enable(clk);
  58         spin_unlock_irqrestore(&clocks_lock, flags);
  59         return 0;
  60 }
  61 EXPORT_SYMBOL(clk_enable);
  62
  63 void clk_disable(struct clk *clk)
  64 {
  65         unsigned long flags;
  66
  67         if (!clk)
  68                 return;
  69
  70         WARN_ON(clk->enabled == 0);
  71
  72         spin_lock_irqsave(&clocks_lock, flags);
  73         if (--clk->enabled == 0)
  74                 clk->ops->disable(clk);
  75         spin_unlock_irqrestore(&clocks_lock, flags);
  76 }
  77 EXPORT_SYMBOL(clk_disable);
  78
  79 unsigned long clk_get_rate(struct clk *clk)
  80 {
  81         unsigned long rate;
  82
  83         if (clk->ops->getrate)
  84                 rate = clk->ops->getrate(clk);
  85         else
  86                 rate = clk->rate;
  87
  88         return rate;
  89 }
  90 EXPORT_SYMBOL(clk_get_rate);
  91
  92 int clk_set_rate(struct clk *clk, unsigned long rate)
  93 {
  94         unsigned long flags;
  95         int ret = -EINVAL;
  96
  97         if (clk->ops->setrate) {
  98                 spin_lock_irqsave(&clocks_lock, flags);
  99                 ret = clk->ops->setrate(clk, rate);
 100                 spin_unlock_irqrestore(&clocks_lock, flags);
 101         }
 102
 103         return ret;
 104 }
 105 EXPORT_SYMBOL(clk_set_rate);