drivers/clk/socfpga/clk-pll-a10.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2015 Altera Corporation. All rights reserved
   4  */
   5 #include <linux/slab.h>
   6 #include <linux/clk-provider.h>
   7 #include <linux/io.h>
   8 #include <linux/of.h>
   9 #include <linux/of_address.h>
  10
  11 #include "clk.h"
  12
  13 /* Clock Manager offsets */
  14 #define CLK_MGR_PLL_CLK_SRC_SHIFT       8
  15 #define CLK_MGR_PLL_CLK_SRC_MASK        0x3
  16
  17 /* Clock bypass bits */
  18 #define SOCFPGA_PLL_BG_PWRDWN           0
  19 #define SOCFPGA_PLL_PWR_DOWN            1
  20 #define SOCFPGA_PLL_EXT_ENA             2
  21 #define SOCFPGA_PLL_DIVF_MASK           0x00001FFF
  22 #define SOCFPGA_PLL_DIVF_SHIFT  0
  23 #define SOCFPGA_PLL_DIVQ_MASK           0x003F0000
  24 #define SOCFPGA_PLL_DIVQ_SHIFT  16
  25 #define SOCFGPA_MAX_PARENTS     5
  26
  27 #define SOCFPGA_MAIN_PLL_CLK            "main_pll"
  28 #define SOCFPGA_PERIP_PLL_CLK           "periph_pll"
  29
  30 #define to_socfpga_clk(p) container_of(p, struct socfpga_pll, hw.hw)
  31
  32 void __iomem *clk_mgr_a10_base_addr;
  33
  34 static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
  35                                          unsigned long parent_rate)
  36 {
  37         struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
  38         unsigned long divf, divq, reg;
  39         unsigned long long vco_freq;
  40
  41         /* read VCO1 reg for numerator and denominator */
  42         reg = readl(socfpgaclk->hw.reg + 0x4);
  43         divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT;
  44         divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT;
  45         vco_freq = (unsigned long long)parent_rate * (divf + 1);
  46         do_div(vco_freq, (1 + divq));
  47         return (unsigned long)vco_freq;
  48 }
  49
  50 static u8 clk_pll_get_parent(struct clk_hw *hwclk)
  51 {
  52         struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk);
  53         u32 pll_src;
  54
  55         pll_src = readl(socfpgaclk->hw.reg);
  56
  57         return (pll_src >> CLK_MGR_PLL_CLK_SRC_SHIFT) &
  58                 CLK_MGR_PLL_CLK_SRC_MASK;
  59 }
  60
  61 static const struct clk_ops clk_pll_ops = {
  62         .recalc_rate = clk_pll_recalc_rate,
  63         .get_parent = clk_pll_get_parent,
  64 };
  65
  66 static struct clk * __init __socfpga_pll_init(struct device_node *node,
  67         const struct clk_ops *ops)
  68 {
  69         u32 reg;
  70         struct clk *clk;
  71         struct socfpga_pll *pll_clk;
  72         const char *clk_name = node->name;
  73         const char *parent_name[SOCFGPA_MAX_PARENTS];
  74         struct clk_init_data init;
  75         struct device_node *clkmgr_np;
  76         int rc;
  77         int i = 0;
  78
  79         of_property_read_u32(node, "reg", &reg);
  80
  81         pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
  82         if (WARN_ON(!pll_clk))
  83                 return NULL;
  84
  85         clkmgr_np = of_find_compatible_node(NULL, NULL, "altr,clk-mgr");
  86         clk_mgr_a10_base_addr = of_iomap(clkmgr_np, 0);
  87         of_node_put(clkmgr_np);
  88         BUG_ON(!clk_mgr_a10_base_addr);
  89         pll_clk->hw.reg = clk_mgr_a10_base_addr + reg;
  90
  91         of_property_read_string(node, "clock-output-names", &clk_name);
  92
  93         init.name = clk_name;
  94         init.ops = ops;
  95         init.flags = 0;
  96
  97         while (i < SOCFGPA_MAX_PARENTS && (parent_name[i] =
  98                         of_clk_get_parent_name(node, i)) != NULL)
  99                 i++;
 100         init.num_parents = i;
 101         init.parent_names = parent_name;
 102         pll_clk->hw.hw.init = &init;
 103
 104         pll_clk->hw.bit_idx = SOCFPGA_PLL_EXT_ENA;
 105
 106         clk = clk_register(NULL, &pll_clk->hw.hw);
 107         if (WARN_ON(IS_ERR(clk))) {
 108                 kfree(pll_clk);
 109                 return NULL;
 110         }
 111         rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
 112         return clk;
 113 }
 114
 115 void __init socfpga_a10_pll_init(struct device_node *node)
 116 {
 117         __socfpga_pll_init(node, &clk_pll_ops);
 118 }