drivers/clk/tegra/clk-pll-out.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/io.h>
   8 #include <linux/err.h>
   9 #include <linux/delay.h>
  10 #include <linux/slab.h>
  11 #include <linux/clk-provider.h>
  12
  13 #include "clk.h"
  14
  15 #define pll_out_enb(p) (BIT(p->enb_bit_idx))
  16 #define pll_out_rst(p) (BIT(p->rst_bit_idx))
  17
  18 static int clk_pll_out_is_enabled(struct clk_hw *hw)
  19 {
  20         struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
  21         u32 val = readl_relaxed(pll_out->reg);
  22         int state;
  23
  24         state = (val & pll_out_enb(pll_out)) ? 1 : 0;
  25         if (!(val & (pll_out_rst(pll_out))))
  26                 state = 0;
  27         return state;
  28 }
  29
  30 static int clk_pll_out_enable(struct clk_hw *hw)
  31 {
  32         struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
  33         unsigned long flags = 0;
  34         u32 val;
  35
  36         if (pll_out->lock)
  37                 spin_lock_irqsave(pll_out->lock, flags);
  38
  39         val = readl_relaxed(pll_out->reg);
  40
  41         val |= (pll_out_enb(pll_out) | pll_out_rst(pll_out));
  42
  43         writel_relaxed(val, pll_out->reg);
  44         udelay(2);
  45
  46         if (pll_out->lock)
  47                 spin_unlock_irqrestore(pll_out->lock, flags);
  48
  49         return 0;
  50 }
  51
  52 static void clk_pll_out_disable(struct clk_hw *hw)
  53 {
  54         struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw);
  55         unsigned long flags = 0;
  56         u32 val;
  57
  58         if (pll_out->lock)
  59                 spin_lock_irqsave(pll_out->lock, flags);
  60
  61         val = readl_relaxed(pll_out->reg);
  62
  63         val &= ~(pll_out_enb(pll_out) | pll_out_rst(pll_out));
  64
  65         writel_relaxed(val, pll_out->reg);
  66         udelay(2);
  67
  68         if (pll_out->lock)
  69                 spin_unlock_irqrestore(pll_out->lock, flags);
  70 }
  71
  72 const struct clk_ops tegra_clk_pll_out_ops = {
  73         .is_enabled = clk_pll_out_is_enabled,
  74         .enable = clk_pll_out_enable,
  75         .disable = clk_pll_out_disable,
  76 };
  77
  78 struct clk *tegra_clk_register_pll_out(const char *name,
  79                 const char *parent_name, void __iomem *reg, u8 enb_bit_idx,
  80                 u8 rst_bit_idx, unsigned long flags, u8 pll_out_flags,
  81                 spinlock_t *lock)
  82 {
  83         struct tegra_clk_pll_out *pll_out;
  84         struct clk *clk;
  85         struct clk_init_data init;
  86
  87         pll_out = kzalloc(sizeof(*pll_out), GFP_KERNEL);
  88         if (!pll_out)
  89                 return ERR_PTR(-ENOMEM);
  90
  91         init.name = name;
  92         init.ops = &tegra_clk_pll_out_ops;
  93         init.parent_names = (parent_name ? &parent_name : NULL);
  94         init.num_parents = (parent_name ? 1 : 0);
  95         init.flags = flags;
  96
  97         pll_out->reg = reg;
  98         pll_out->enb_bit_idx = enb_bit_idx;
  99         pll_out->rst_bit_idx = rst_bit_idx;
 100         pll_out->flags = pll_out_flags;
 101         pll_out->lock = lock;
 102
 103         /* Data in .init is copied by clk_register(), so stack variable OK */
 104         pll_out->hw.init = &init;
 105
 106         clk = clk_register(NULL, &pll_out->hw);
 107         if (IS_ERR(clk))
 108                 kfree(pll_out);
 109
 110         return clk;
 111 }