drivers/clk/ti/gate.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * OMAP gate clock support
   4  *
   5  * Copyright (C) 2013 Texas Instruments, Inc.
   6  *
   7  * Tero Kristo <t-kristo@ti.com>
   8  */
   9
  10 #include <linux/clk-provider.h>
  11 #include <linux/slab.h>
  12 #include <linux/io.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15 #include <linux/clk/ti.h>
  16
  17 #include "clock.h"
  18
  19 #undef pr_fmt
  20 #define pr_fmt(fmt) "%s: " fmt, __func__
  21
  22 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *clk);
  23
  24 static const struct clk_ops omap_gate_clkdm_clk_ops = {
  25         .init           = &omap2_init_clk_clkdm,
  26         .enable         = &omap2_clkops_enable_clkdm,
  27         .disable        = &omap2_clkops_disable_clkdm,
  28         .restore_context = clk_gate_restore_context,
  29 };
  30
  31 const struct clk_ops omap_gate_clk_ops = {
  32         .init           = &omap2_init_clk_clkdm,
  33         .enable         = &omap2_dflt_clk_enable,
  34         .disable        = &omap2_dflt_clk_disable,
  35         .is_enabled     = &omap2_dflt_clk_is_enabled,
  36         .restore_context = clk_gate_restore_context,
  37 };
  38
  39 static const struct clk_ops omap_gate_clk_hsdiv_restore_ops = {
  40         .init           = &omap2_init_clk_clkdm,
  41         .enable         = &omap36xx_gate_clk_enable_with_hsdiv_restore,
  42         .disable        = &omap2_dflt_clk_disable,
  43         .is_enabled     = &omap2_dflt_clk_is_enabled,
  44         .restore_context = clk_gate_restore_context,
  45 };
  46
  47 /**
  48  * omap36xx_gate_clk_enable_with_hsdiv_restore - enable clocks suffering
  49  *         from HSDivider PWRDN problem Implements Errata ID: i556.
  50  * @hw: DPLL output struct clk_hw
  51  *
  52  * 3630 only: dpll3_m3_ck, dpll4_m2_ck, dpll4_m3_ck, dpll4_m4_ck,
  53  * dpll4_m5_ck & dpll4_m6_ck dividers gets loaded with reset
  54  * valueafter their respective PWRDN bits are set.  Any dummy write
  55  * (Any other value different from the Read value) to the
  56  * corresponding CM_CLKSEL register will refresh the dividers.
  57  */
  58 static int omap36xx_gate_clk_enable_with_hsdiv_restore(struct clk_hw *hw)
  59 {
  60         struct clk_omap_divider *parent;
  61         struct clk_hw *parent_hw;
  62         u32 dummy_v, orig_v;
  63         int ret;
  64
  65         /* Clear PWRDN bit of HSDIVIDER */
  66         ret = omap2_dflt_clk_enable(hw);
  67
  68         /* Parent is the x2 node, get parent of parent for the m2 div */
  69         parent_hw = clk_hw_get_parent(clk_hw_get_parent(hw));
  70         parent = to_clk_omap_divider(parent_hw);
  71
  72         /* Restore the dividers */
  73         if (!ret) {
  74                 orig_v = ti_clk_ll_ops->clk_readl(&parent->reg);
  75                 dummy_v = orig_v;
  76
  77                 /* Write any other value different from the Read value */
  78                 dummy_v ^= (1 << parent->shift);
  79                 ti_clk_ll_ops->clk_writel(dummy_v, &parent->reg);
  80
  81                 /* Write the original divider */
  82                 ti_clk_ll_ops->clk_writel(orig_v, &parent->reg);
  83         }
  84
  85         return ret;
  86 }
  87
  88 static struct clk *_register_gate(struct device_node *node, const char *name,
  89                                   const char *parent_name, unsigned long flags,
  90                                   struct clk_omap_reg *reg, u8 bit_idx,
  91                                   u8 clk_gate_flags, const struct clk_ops *ops,
  92                                   const struct clk_hw_omap_ops *hw_ops)
  93 {
  94         struct clk_init_data init = { NULL };
  95         struct clk_hw_omap *clk_hw;
  96         struct clk *clk;
  97
  98         clk_hw = kzalloc(sizeof(*clk_hw), GFP_KERNEL);
  99         if (!clk_hw)
 100                 return ERR_PTR(-ENOMEM);
 101
 102         clk_hw->hw.init = &init;
 103
 104         init.name = name;
 105         init.ops = ops;
 106
 107         memcpy(&clk_hw->enable_reg, reg, sizeof(*reg));
 108         clk_hw->enable_bit = bit_idx;
 109         clk_hw->ops = hw_ops;
 110
 111         clk_hw->flags = clk_gate_flags;
 112
 113         init.parent_names = &parent_name;
 114         init.num_parents = 1;
 115
 116         init.flags = flags;
 117
 118         clk = of_ti_clk_register_omap_hw(node, &clk_hw->hw, name);
 119
 120         if (IS_ERR(clk))
 121                 kfree(clk_hw);
 122
 123         return clk;
 124 }
 125
 126 static void __init _of_ti_gate_clk_setup(struct device_node *node,
 127                                          const struct clk_ops *ops,
 128                                          const struct clk_hw_omap_ops *hw_ops)
 129 {
 130         struct clk *clk;
 131         const char *parent_name;
 132         struct clk_omap_reg reg;
 133         const char *name;
 134         u8 enable_bit = 0;
 135         u32 flags = 0;
 136         u8 clk_gate_flags = 0;
 137
 138         if (ops != &omap_gate_clkdm_clk_ops) {
 139                 if (ti_clk_get_reg_addr(node, 0, &reg))
 140                         return;
 141
 142                 enable_bit = reg.bit;
 143         }
 144
 145         if (of_clk_get_parent_count(node) != 1) {
 146                 pr_err("%pOFn must have 1 parent\n", node);
 147                 return;
 148         }
 149
 150         parent_name = of_clk_get_parent_name(node, 0);
 151
 152         if (of_property_read_bool(node, "ti,set-rate-parent"))
 153                 flags |= CLK_SET_RATE_PARENT;
 154
 155         if (of_property_read_bool(node, "ti,set-bit-to-disable"))
 156                 clk_gate_flags |= INVERT_ENABLE;
 157
 158         name = ti_dt_clk_name(node);
 159         clk = _register_gate(node, name, parent_name, flags, &reg,
 160                              enable_bit, clk_gate_flags, ops, hw_ops);
 161
 162         if (!IS_ERR(clk))
 163                 of_clk_add_provider(node, of_clk_src_simple_get, clk);
 164 }
 165
 166 static void __init
 167 _of_ti_composite_gate_clk_setup(struct device_node *node,
 168                                 const struct clk_hw_omap_ops *hw_ops)
 169 {
 170         struct clk_hw_omap *gate;
 171
 172         gate = kzalloc(sizeof(*gate), GFP_KERNEL);
 173         if (!gate)
 174                 return;
 175
 176         if (ti_clk_get_reg_addr(node, 0, &gate->enable_reg))
 177                 goto cleanup;
 178
 179         gate->enable_bit = gate->enable_reg.bit;
 180         gate->ops = hw_ops;
 181
 182         if (!ti_clk_add_component(node, &gate->hw, CLK_COMPONENT_TYPE_GATE))
 183                 return;
 184
 185 cleanup:
 186         kfree(gate);
 187 }
 188
 189 static void __init
 190 of_ti_composite_no_wait_gate_clk_setup(struct device_node *node)
 191 {
 192         _of_ti_composite_gate_clk_setup(node, NULL);
 193 }
 194 CLK_OF_DECLARE(ti_composite_no_wait_gate_clk, "ti,composite-no-wait-gate-clock",
 195                of_ti_composite_no_wait_gate_clk_setup);
 196
 197 #if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
 198 static void __init of_ti_composite_interface_clk_setup(struct device_node *node)
 199 {
 200         _of_ti_composite_gate_clk_setup(node, &clkhwops_iclk_wait);
 201 }
 202 CLK_OF_DECLARE(ti_composite_interface_clk, "ti,composite-interface-clock",
 203                of_ti_composite_interface_clk_setup);
 204 #endif
 205
 206 static void __init of_ti_composite_gate_clk_setup(struct device_node *node)
 207 {
 208         _of_ti_composite_gate_clk_setup(node, &clkhwops_wait);
 209 }
 210 CLK_OF_DECLARE(ti_composite_gate_clk, "ti,composite-gate-clock",
 211                of_ti_composite_gate_clk_setup);
 212
 213
 214 static void __init of_ti_clkdm_gate_clk_setup(struct device_node *node)
 215 {
 216         _of_ti_gate_clk_setup(node, &omap_gate_clkdm_clk_ops, NULL);
 217 }
 218 CLK_OF_DECLARE(ti_clkdm_gate_clk, "ti,clkdm-gate-clock",
 219                of_ti_clkdm_gate_clk_setup);
 220
 221 static void __init of_ti_hsdiv_gate_clk_setup(struct device_node *node)
 222 {
 223         _of_ti_gate_clk_setup(node, &omap_gate_clk_hsdiv_restore_ops,
 224                               &clkhwops_wait);
 225 }
 226 CLK_OF_DECLARE(ti_hsdiv_gate_clk, "ti,hsdiv-gate-clock",
 227                of_ti_hsdiv_gate_clk_setup);
 228
 229 static void __init of_ti_gate_clk_setup(struct device_node *node)
 230 {
 231         _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, NULL);
 232 }
 233 CLK_OF_DECLARE(ti_gate_clk, "ti,gate-clock", of_ti_gate_clk_setup);
 234
 235 static void __init of_ti_wait_gate_clk_setup(struct device_node *node)
 236 {
 237         _of_ti_gate_clk_setup(node, &omap_gate_clk_ops, &clkhwops_wait);
 238 }
 239 CLK_OF_DECLARE(ti_wait_gate_clk, "ti,wait-gate-clock",
 240                of_ti_wait_gate_clk_setup);
 241
 242 #ifdef CONFIG_ARCH_OMAP3
 243 static void __init of_ti_am35xx_gate_clk_setup(struct device_node *node)
 244 {
 245         _of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
 246                               &clkhwops_am35xx_ipss_module_wait);
 247 }
 248 CLK_OF_DECLARE(ti_am35xx_gate_clk, "ti,am35xx-gate-clock",
 249                of_ti_am35xx_gate_clk_setup);
 250
 251 static void __init of_ti_dss_gate_clk_setup(struct device_node *node)
 252 {
 253         _of_ti_gate_clk_setup(node, &omap_gate_clk_ops,
 254                               &clkhwops_omap3430es2_dss_usbhost_wait);
 255 }
 256 CLK_OF_DECLARE(ti_dss_gate_clk, "ti,dss-gate-clock",
 257                of_ti_dss_gate_clk_setup);
 258 #endif