drivers/clk/sunxi/clk-sun8i-bus-gates.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2015 Jens Kuske <jenskuske@gmail.com>
   4  *
   5  * Based on clk-simple-gates.c, which is:
   6  * Copyright 2015 Maxime Ripard
   7  *
   8  * Maxime Ripard <maxime.ripard@free-electrons.com>
   9  */
  10
  11 #include <linux/clk-provider.h>
  12 #include <linux/io.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15 #include <linux/slab.h>
  16 #include <linux/spinlock.h>
  17
  18 static DEFINE_SPINLOCK(gates_lock);
  19
  20 static void __init sun8i_h3_bus_gates_init(struct device_node *node)
  21 {
  22         static const char * const names[] = { "ahb1", "ahb2", "apb1", "apb2" };
  23         enum { AHB1, AHB2, APB1, APB2, PARENT_MAX } clk_parent;
  24         const char *parents[PARENT_MAX];
  25         struct clk_onecell_data *clk_data;
  26         const char *clk_name;
  27         struct property *prop;
  28         struct resource res;
  29         void __iomem *clk_reg;
  30         void __iomem *reg;
  31         const __be32 *p;
  32         int number, i;
  33         u8 clk_bit;
  34         int index;
  35
  36         reg = of_io_request_and_map(node, 0, of_node_full_name(node));
  37         if (IS_ERR(reg))
  38                 return;
  39
  40         for (i = 0; i < ARRAY_SIZE(names); i++) {
  41                 int idx = of_property_match_string(node, "clock-names",
  42                                                    names[i]);
  43                 if (idx < 0)
  44                         return;
  45
  46                 parents[i] = of_clk_get_parent_name(node, idx);
  47         }
  48
  49         clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
  50         if (!clk_data)
  51                 goto err_unmap;
  52
  53         number = of_property_count_u32_elems(node, "clock-indices");
  54         of_property_read_u32_index(node, "clock-indices", number - 1, &number);
  55
  56         clk_data->clks = kcalloc(number + 1, sizeof(struct clk *), GFP_KERNEL);
  57         if (!clk_data->clks)
  58                 goto err_free_data;
  59
  60         i = 0;
  61         of_property_for_each_u32(node, "clock-indices", prop, p, index) {
  62                 of_property_read_string_index(node, "clock-output-names",
  63                                               i, &clk_name);
  64
  65                 if (index == 17 || (index >= 29 && index <= 31))
  66                         clk_parent = AHB2;
  67                 else if (index <= 63 || index >= 128)
  68                         clk_parent = AHB1;
  69                 else if (index >= 64 && index <= 95)
  70                         clk_parent = APB1;
  71                 else if (index >= 96 && index <= 127)
  72                         clk_parent = APB2;
  73                 else {
  74                         WARN_ON(true);
  75                         continue;
  76                 }
  77
  78                 clk_reg = reg + 4 * (index / 32);
  79                 clk_bit = index % 32;
  80
  81                 clk_data->clks[index] = clk_register_gate(NULL, clk_name,
  82                                                           parents[clk_parent],
  83                                                           0, clk_reg, clk_bit,
  84                                                           0, &gates_lock);
  85                 i++;
  86
  87                 if (IS_ERR(clk_data->clks[index])) {
  88                         WARN_ON(true);
  89                         continue;
  90                 }
  91         }
  92
  93         clk_data->clk_num = number + 1;
  94         of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
  95
  96         return;
  97
  98 err_free_data:
  99         kfree(clk_data);
 100 err_unmap:
 101         iounmap(reg);
 102         of_address_to_resource(node, 0, &res);
 103         release_mem_region(res.start, resource_size(&res));
 104 }
 105
 106 CLK_OF_DECLARE(sun8i_h3_bus_gates, "allwinner,sun8i-h3-bus-gates-clk",
 107                sun8i_h3_bus_gates_init);
 108 CLK_OF_DECLARE(sun8i_a83t_bus_gates, "allwinner,sun8i-a83t-bus-gates-clk",
 109                sun8i_h3_bus_gates_init);