kernel/drivers/clk/ux500/clk-prcmu.c

   1 /*
   2  * PRCMU clock implementation for ux500 platform.
   3  *
   4  * Copyright (C) 2012 ST-Ericsson SA
   5  * Author: Ulf Hansson <ulf.hansson@linaro.org>
   6  *
   7  * License terms: GNU General Public License (GPL) version 2
   8  */
   9
  10 #include <linux/clk-provider.h>
  11 #include <linux/mfd/dbx500-prcmu.h>
  12 #include <linux/slab.h>
  13 #include <linux/io.h>
  14 #include <linux/err.h>
  15 #include "clk.h"
  16
  17 #define to_clk_prcmu(_hw) container_of(_hw, struct clk_prcmu, hw)
  18
  19 struct clk_prcmu {
  20         struct clk_hw hw;
  21         u8 cg_sel;
  22         int is_prepared;
  23         int is_enabled;
  24         int opp_requested;
  25 };
  26
  27 /* PRCMU clock operations. */
  28
  29 static int clk_prcmu_prepare(struct clk_hw *hw)
  30 {
  31         int ret;
  32         struct clk_prcmu *clk = to_clk_prcmu(hw);
  33
  34         ret = prcmu_request_clock(clk->cg_sel, true);
  35         if (!ret)
  36                 clk->is_prepared = 1;
  37
  38         return ret;
  39 }
  40
  41 static void clk_prcmu_unprepare(struct clk_hw *hw)
  42 {
  43         struct clk_prcmu *clk = to_clk_prcmu(hw);
  44         if (prcmu_request_clock(clk->cg_sel, false))
  45                 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
  46                         clk_hw_get_name(hw));
  47         else
  48                 clk->is_prepared = 0;
  49 }
  50
  51 static int clk_prcmu_is_prepared(struct clk_hw *hw)
  52 {
  53         struct clk_prcmu *clk = to_clk_prcmu(hw);
  54         return clk->is_prepared;
  55 }
  56
  57 static int clk_prcmu_enable(struct clk_hw *hw)
  58 {
  59         struct clk_prcmu *clk = to_clk_prcmu(hw);
  60         clk->is_enabled = 1;
  61         return 0;
  62 }
  63
  64 static void clk_prcmu_disable(struct clk_hw *hw)
  65 {
  66         struct clk_prcmu *clk = to_clk_prcmu(hw);
  67         clk->is_enabled = 0;
  68 }
  69
  70 static int clk_prcmu_is_enabled(struct clk_hw *hw)
  71 {
  72         struct clk_prcmu *clk = to_clk_prcmu(hw);
  73         return clk->is_enabled;
  74 }
  75
  76 static unsigned long clk_prcmu_recalc_rate(struct clk_hw *hw,
  77                                            unsigned long parent_rate)
  78 {
  79         struct clk_prcmu *clk = to_clk_prcmu(hw);
  80         return prcmu_clock_rate(clk->cg_sel);
  81 }
  82
  83 static long clk_prcmu_round_rate(struct clk_hw *hw, unsigned long rate,
  84                                  unsigned long *parent_rate)
  85 {
  86         struct clk_prcmu *clk = to_clk_prcmu(hw);
  87         return prcmu_round_clock_rate(clk->cg_sel, rate);
  88 }
  89
  90 static int clk_prcmu_set_rate(struct clk_hw *hw, unsigned long rate,
  91                               unsigned long parent_rate)
  92 {
  93         struct clk_prcmu *clk = to_clk_prcmu(hw);
  94         return prcmu_set_clock_rate(clk->cg_sel, rate);
  95 }
  96
  97 static int clk_prcmu_opp_prepare(struct clk_hw *hw)
  98 {
  99         int err;
 100         struct clk_prcmu *clk = to_clk_prcmu(hw);
 101
 102         if (!clk->opp_requested) {
 103                 err = prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP,
 104                                                 (char *)clk_hw_get_name(hw),
 105                                                 100);
 106                 if (err) {
 107                         pr_err("clk_prcmu: %s fail req APE OPP for %s.\n",
 108                                 __func__, clk_hw_get_name(hw));
 109                         return err;
 110                 }
 111                 clk->opp_requested = 1;
 112         }
 113
 114         err = prcmu_request_clock(clk->cg_sel, true);
 115         if (err) {
 116                 prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP,
 117                                         (char *)clk_hw_get_name(hw));
 118                 clk->opp_requested = 0;
 119                 return err;
 120         }
 121
 122         clk->is_prepared = 1;
 123         return 0;
 124 }
 125
 126 static void clk_prcmu_opp_unprepare(struct clk_hw *hw)
 127 {
 128         struct clk_prcmu *clk = to_clk_prcmu(hw);
 129
 130         if (prcmu_request_clock(clk->cg_sel, false)) {
 131                 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
 132                         clk_hw_get_name(hw));
 133                 return;
 134         }
 135
 136         if (clk->opp_requested) {
 137                 prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP,
 138                                         (char *)clk_hw_get_name(hw));
 139                 clk->opp_requested = 0;
 140         }
 141
 142         clk->is_prepared = 0;
 143 }
 144
 145 static int clk_prcmu_opp_volt_prepare(struct clk_hw *hw)
 146 {
 147         int err;
 148         struct clk_prcmu *clk = to_clk_prcmu(hw);
 149
 150         if (!clk->opp_requested) {
 151                 err = prcmu_request_ape_opp_100_voltage(true);
 152                 if (err) {
 153                         pr_err("clk_prcmu: %s fail req APE OPP VOLT for %s.\n",
 154                                 __func__, clk_hw_get_name(hw));
 155                         return err;
 156                 }
 157                 clk->opp_requested = 1;
 158         }
 159
 160         err = prcmu_request_clock(clk->cg_sel, true);
 161         if (err) {
 162                 prcmu_request_ape_opp_100_voltage(false);
 163                 clk->opp_requested = 0;
 164                 return err;
 165         }
 166
 167         clk->is_prepared = 1;
 168         return 0;
 169 }
 170
 171 static void clk_prcmu_opp_volt_unprepare(struct clk_hw *hw)
 172 {
 173         struct clk_prcmu *clk = to_clk_prcmu(hw);
 174
 175         if (prcmu_request_clock(clk->cg_sel, false)) {
 176                 pr_err("clk_prcmu: %s failed to disable %s.\n", __func__,
 177                         clk_hw_get_name(hw));
 178                 return;
 179         }
 180
 181         if (clk->opp_requested) {
 182                 prcmu_request_ape_opp_100_voltage(false);
 183                 clk->opp_requested = 0;
 184         }
 185
 186         clk->is_prepared = 0;
 187 }
 188
 189 static struct clk_ops clk_prcmu_scalable_ops = {
 190         .prepare = clk_prcmu_prepare,
 191         .unprepare = clk_prcmu_unprepare,
 192         .is_prepared = clk_prcmu_is_prepared,
 193         .enable = clk_prcmu_enable,
 194         .disable = clk_prcmu_disable,
 195         .is_enabled = clk_prcmu_is_enabled,
 196         .recalc_rate = clk_prcmu_recalc_rate,
 197         .round_rate = clk_prcmu_round_rate,
 198         .set_rate = clk_prcmu_set_rate,
 199 };
 200
 201 static struct clk_ops clk_prcmu_gate_ops = {
 202         .prepare = clk_prcmu_prepare,
 203         .unprepare = clk_prcmu_unprepare,
 204         .is_prepared = clk_prcmu_is_prepared,
 205         .enable = clk_prcmu_enable,
 206         .disable = clk_prcmu_disable,
 207         .is_enabled = clk_prcmu_is_enabled,
 208         .recalc_rate = clk_prcmu_recalc_rate,
 209 };
 210
 211 static struct clk_ops clk_prcmu_scalable_rate_ops = {
 212         .is_enabled = clk_prcmu_is_enabled,
 213         .recalc_rate = clk_prcmu_recalc_rate,
 214         .round_rate = clk_prcmu_round_rate,
 215         .set_rate = clk_prcmu_set_rate,
 216 };
 217
 218 static struct clk_ops clk_prcmu_rate_ops = {
 219         .is_enabled = clk_prcmu_is_enabled,
 220         .recalc_rate = clk_prcmu_recalc_rate,
 221 };
 222
 223 static struct clk_ops clk_prcmu_opp_gate_ops = {
 224         .prepare = clk_prcmu_opp_prepare,
 225         .unprepare = clk_prcmu_opp_unprepare,
 226         .is_prepared = clk_prcmu_is_prepared,
 227         .enable = clk_prcmu_enable,
 228         .disable = clk_prcmu_disable,
 229         .is_enabled = clk_prcmu_is_enabled,
 230         .recalc_rate = clk_prcmu_recalc_rate,
 231 };
 232
 233 static struct clk_ops clk_prcmu_opp_volt_scalable_ops = {
 234         .prepare = clk_prcmu_opp_volt_prepare,
 235         .unprepare = clk_prcmu_opp_volt_unprepare,
 236         .is_prepared = clk_prcmu_is_prepared,
 237         .enable = clk_prcmu_enable,
 238         .disable = clk_prcmu_disable,
 239         .is_enabled = clk_prcmu_is_enabled,
 240         .recalc_rate = clk_prcmu_recalc_rate,
 241         .round_rate = clk_prcmu_round_rate,
 242         .set_rate = clk_prcmu_set_rate,
 243 };
 244
 245 static struct clk *clk_reg_prcmu(const char *name,
 246                                  const char *parent_name,
 247                                  u8 cg_sel,
 248                                  unsigned long rate,
 249                                  unsigned long flags,
 250                                  struct clk_ops *clk_prcmu_ops)
 251 {
 252         struct clk_prcmu *clk;
 253         struct clk_init_data clk_prcmu_init;
 254         struct clk *clk_reg;
 255
 256         if (!name) {
 257                 pr_err("clk_prcmu: %s invalid arguments passed\n", __func__);
 258                 return ERR_PTR(-EINVAL);
 259         }
 260
 261         clk = kzalloc(sizeof(struct clk_prcmu), GFP_KERNEL);
 262         if (!clk) {
 263                 pr_err("clk_prcmu: %s could not allocate clk\n", __func__);
 264                 return ERR_PTR(-ENOMEM);
 265         }
 266
 267         clk->cg_sel = cg_sel;
 268         clk->is_prepared = 1;
 269         clk->is_enabled = 1;
 270         clk->opp_requested = 0;
 271         /* "rate" can be used for changing the initial frequency */
 272         if (rate)
 273                 prcmu_set_clock_rate(cg_sel, rate);
 274
 275         clk_prcmu_init.name = name;
 276         clk_prcmu_init.ops = clk_prcmu_ops;
 277         clk_prcmu_init.flags = flags;
 278         clk_prcmu_init.parent_names = (parent_name ? &parent_name : NULL);
 279         clk_prcmu_init.num_parents = (parent_name ? 1 : 0);
 280         clk->hw.init = &clk_prcmu_init;
 281
 282         clk_reg = clk_register(NULL, &clk->hw);
 283         if (IS_ERR_OR_NULL(clk_reg))
 284                 goto free_clk;
 285
 286         return clk_reg;
 287
 288 free_clk:
 289         kfree(clk);
 290         pr_err("clk_prcmu: %s failed to register clk\n", __func__);
 291         return ERR_PTR(-ENOMEM);
 292 }
 293
 294 struct clk *clk_reg_prcmu_scalable(const char *name,
 295                                    const char *parent_name,
 296                                    u8 cg_sel,
 297                                    unsigned long rate,
 298                                    unsigned long flags)
 299 {
 300         return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
 301                         &clk_prcmu_scalable_ops);
 302 }
 303
 304 struct clk *clk_reg_prcmu_gate(const char *name,
 305                                const char *parent_name,
 306                                u8 cg_sel,
 307                                unsigned long flags)
 308 {
 309         return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags,
 310                         &clk_prcmu_gate_ops);
 311 }
 312
 313 struct clk *clk_reg_prcmu_scalable_rate(const char *name,
 314                                         const char *parent_name,
 315                                         u8 cg_sel,
 316                                         unsigned long rate,
 317                                         unsigned long flags)
 318 {
 319         return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
 320                         &clk_prcmu_scalable_rate_ops);
 321 }
 322
 323 struct clk *clk_reg_prcmu_rate(const char *name,
 324                                const char *parent_name,
 325                                u8 cg_sel,
 326                                unsigned long flags)
 327 {
 328         return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags,
 329                         &clk_prcmu_rate_ops);
 330 }
 331
 332 struct clk *clk_reg_prcmu_opp_gate(const char *name,
 333                                    const char *parent_name,
 334                                    u8 cg_sel,
 335                                    unsigned long flags)
 336 {
 337         return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags,
 338                         &clk_prcmu_opp_gate_ops);
 339 }
 340
 341 struct clk *clk_reg_prcmu_opp_volt_scalable(const char *name,
 342                                             const char *parent_name,
 343                                             u8 cg_sel,
 344                                             unsigned long rate,
 345                                             unsigned long flags)
 346 {
 347         return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags,
 348                         &clk_prcmu_opp_volt_scalable_ops);
 349 }