drivers/sh/clk/cpg.c

   1 /*
   2  * Helper routines for SuperH Clock Pulse Generator blocks (CPG).
   3  *
   4  *  Copyright (C) 2010  Magnus Damm
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10 #include <linux/clk.h>
  11 #include <linux/compiler.h>
  12 #include <linux/slab.h>
  13 #include <linux/io.h>
  14 #include <linux/sh_clk.h>
  15
  16 static int sh_clk_mstp32_enable(struct clk *clk)
  17 {
  18         __raw_writel(__raw_readl(clk->enable_reg) & ~(1 << clk->enable_bit),
  19                      clk->enable_reg);
  20         return 0;
  21 }
  22
  23 static void sh_clk_mstp32_disable(struct clk *clk)
  24 {
  25         __raw_writel(__raw_readl(clk->enable_reg) | (1 << clk->enable_bit),
  26                      clk->enable_reg);
  27 }
  28
  29 static struct clk_ops sh_clk_mstp32_clk_ops = {
  30         .enable         = sh_clk_mstp32_enable,
  31         .disable        = sh_clk_mstp32_disable,
  32         .recalc         = followparent_recalc,
  33 };
  34
  35 int __init sh_clk_mstp32_register(struct clk *clks, int nr)
  36 {
  37         struct clk *clkp;
  38         int ret = 0;
  39         int k;
  40
  41         for (k = 0; !ret && (k < nr); k++) {
  42                 clkp = clks + k;
  43                 clkp->ops = &sh_clk_mstp32_clk_ops;
  44                 ret |= clk_register(clkp);
  45         }
  46
  47         return ret;
  48 }
  49
  50 static long sh_clk_div_round_rate(struct clk *clk, unsigned long rate)
  51 {
  52         return clk_rate_table_round(clk, clk->freq_table, rate);
  53 }
  54
  55 static int sh_clk_div6_divisors[64] = {
  56         1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
  57         17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
  58         33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
  59         49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64
  60 };
  61
  62 static struct clk_div_mult_table sh_clk_div6_table = {
  63         .divisors = sh_clk_div6_divisors,
  64         .nr_divisors = ARRAY_SIZE(sh_clk_div6_divisors),
  65 };
  66
  67 static unsigned long sh_clk_div6_recalc(struct clk *clk)
  68 {
  69         struct clk_div_mult_table *table = &sh_clk_div6_table;
  70         unsigned int idx;
  71
  72         clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
  73                              table, NULL);
  74
  75         idx = __raw_readl(clk->enable_reg) & 0x003f;
  76
  77         return clk->freq_table[idx].frequency;
  78 }
  79
  80 static int sh_clk_div6_set_parent(struct clk *clk, struct clk *parent)
  81 {
  82         struct clk_div_mult_table *table = &sh_clk_div6_table;
  83         u32 value;
  84         int ret, i;
  85
  86         if (!clk->parent_table || !clk->parent_num)
  87                 return -EINVAL;
  88
  89         /* Search the parent */
  90         for (i = 0; i < clk->parent_num; i++)
  91                 if (clk->parent_table[i] == parent)
  92                         break;
  93
  94         if (i == clk->parent_num)
  95                 return -ENODEV;
  96
  97         ret = clk_reparent(clk, parent);
  98         if (ret < 0)
  99                 return ret;
 100
 101         value = __raw_readl(clk->enable_reg) &
 102                 ~(((1 << clk->src_width) - 1) << clk->src_shift);
 103
 104         __raw_writel(value | (i << clk->src_shift), clk->enable_reg);
 105
 106         /* Rebuild the frequency table */
 107         clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
 108                              table, &clk->arch_flags);
 109
 110         return 0;
 111 }
 112
 113 static int sh_clk_div6_set_rate(struct clk *clk,
 114                                 unsigned long rate, int algo_id)
 115 {
 116         unsigned long value;
 117         int idx;
 118
 119         idx = clk_rate_table_find(clk, clk->freq_table, rate);
 120         if (idx < 0)
 121                 return idx;
 122
 123         value = __raw_readl(clk->enable_reg);
 124         value &= ~0x3f;
 125         value |= idx;
 126         __raw_writel(value, clk->enable_reg);
 127         return 0;
 128 }
 129
 130 static int sh_clk_div6_enable(struct clk *clk)
 131 {
 132         unsigned long value;
 133         int ret;
 134
 135         ret = sh_clk_div6_set_rate(clk, clk->rate, 0);
 136         if (ret == 0) {
 137                 value = __raw_readl(clk->enable_reg);
 138                 value &= ~0x100; /* clear stop bit to enable clock */
 139                 __raw_writel(value, clk->enable_reg);
 140         }
 141         return ret;
 142 }
 143
 144 static void sh_clk_div6_disable(struct clk *clk)
 145 {
 146         unsigned long value;
 147
 148         value = __raw_readl(clk->enable_reg);
 149         value |= 0x100; /* stop clock */
 150         value |= 0x3f; /* VDIV bits must be non-zero, overwrite divider */
 151         __raw_writel(value, clk->enable_reg);
 152 }
 153
 154 static struct clk_ops sh_clk_div6_clk_ops = {
 155         .recalc         = sh_clk_div6_recalc,
 156         .round_rate     = sh_clk_div_round_rate,
 157         .set_rate       = sh_clk_div6_set_rate,
 158         .enable         = sh_clk_div6_enable,
 159         .disable        = sh_clk_div6_disable,
 160 };
 161
 162 static struct clk_ops sh_clk_div6_reparent_clk_ops = {
 163         .recalc         = sh_clk_div6_recalc,
 164         .round_rate     = sh_clk_div_round_rate,
 165         .set_rate       = sh_clk_div6_set_rate,
 166         .enable         = sh_clk_div6_enable,
 167         .disable        = sh_clk_div6_disable,
 168         .set_parent     = sh_clk_div6_set_parent,
 169 };
 170
 171 static int __init sh_clk_div6_register_ops(struct clk *clks, int nr,
 172                                            struct clk_ops *ops)
 173 {
 174         struct clk *clkp;
 175         void *freq_table;
 176         int nr_divs = sh_clk_div6_table.nr_divisors;
 177         int freq_table_size = sizeof(struct cpufreq_frequency_table);
 178         int ret = 0;
 179         int k;
 180
 181         freq_table_size *= (nr_divs + 1);
 182         freq_table = kzalloc(freq_table_size * nr, GFP_KERNEL);
 183         if (!freq_table) {
 184                 pr_err("sh_clk_div6_register: unable to alloc memory\n");
 185                 return -ENOMEM;
 186         }
 187
 188         for (k = 0; !ret && (k < nr); k++) {
 189                 clkp = clks + k;
 190
 191                 clkp->ops = ops;
 192                 clkp->freq_table = freq_table + (k * freq_table_size);
 193                 clkp->freq_table[nr_divs].frequency = CPUFREQ_TABLE_END;
 194
 195                 ret = clk_register(clkp);
 196         }
 197
 198         return ret;
 199 }
 200
 201 int __init sh_clk_div6_register(struct clk *clks, int nr)
 202 {
 203         return sh_clk_div6_register_ops(clks, nr, &sh_clk_div6_clk_ops);
 204 }
 205
 206 int __init sh_clk_div6_reparent_register(struct clk *clks, int nr)
 207 {
 208         return sh_clk_div6_register_ops(clks, nr,
 209                                         &sh_clk_div6_reparent_clk_ops);
 210 }
 211
 212 static unsigned long sh_clk_div4_recalc(struct clk *clk)
 213 {
 214         struct clk_div4_table *d4t = clk->priv;
 215         struct clk_div_mult_table *table = d4t->div_mult_table;
 216         unsigned int idx;
 217
 218         clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
 219                              table, &clk->arch_flags);
 220
 221         idx = (__raw_readl(clk->enable_reg) >> clk->enable_bit) & 0x000f;
 222
 223         return clk->freq_table[idx].frequency;
 224 }
 225
 226 static int sh_clk_div4_set_parent(struct clk *clk, struct clk *parent)
 227 {
 228         struct clk_div4_table *d4t = clk->priv;
 229         struct clk_div_mult_table *table = d4t->div_mult_table;
 230         u32 value;
 231         int ret;
 232
 233         /* we really need a better way to determine parent index, but for
 234          * now assume internal parent comes with CLK_ENABLE_ON_INIT set,
 235          * no CLK_ENABLE_ON_INIT means external clock...
 236          */
 237
 238         if (parent->flags & CLK_ENABLE_ON_INIT)
 239                 value = __raw_readl(clk->enable_reg) & ~(1 << 7);
 240         else
 241                 value = __raw_readl(clk->enable_reg) | (1 << 7);
 242
 243         ret = clk_reparent(clk, parent);
 244         if (ret < 0)
 245                 return ret;
 246
 247         __raw_writel(value, clk->enable_reg);
 248
 249         /* Rebiuld the frequency table */
 250         clk_rate_table_build(clk, clk->freq_table, table->nr_divisors,
 251                              table, &clk->arch_flags);
 252
 253         return 0;
 254 }
 255
 256 static int sh_clk_div4_set_rate(struct clk *clk, unsigned long rate, int algo_id)
 257 {
 258         struct clk_div4_table *d4t = clk->priv;
 259         unsigned long value;
 260         int idx = clk_rate_table_find(clk, clk->freq_table, rate);
 261         if (idx < 0)
 262                 return idx;
 263
 264         value = __raw_readl(clk->enable_reg);
 265         value &= ~(0xf << clk->enable_bit);
 266         value |= (idx << clk->enable_bit);
 267         __raw_writel(value, clk->enable_reg);
 268
 269         if (d4t->kick)
 270                 d4t->kick(clk);
 271
 272         return 0;
 273 }
 274
 275 static int sh_clk_div4_enable(struct clk *clk)
 276 {
 277         __raw_writel(__raw_readl(clk->enable_reg) & ~(1 << 8), clk->enable_reg);
 278         return 0;
 279 }
 280
 281 static void sh_clk_div4_disable(struct clk *clk)
 282 {
 283         __raw_writel(__raw_readl(clk->enable_reg) | (1 << 8), clk->enable_reg);
 284 }
 285
 286 static struct clk_ops sh_clk_div4_clk_ops = {
 287         .recalc         = sh_clk_div4_recalc,
 288         .set_rate       = sh_clk_div4_set_rate,
 289         .round_rate     = sh_clk_div_round_rate,
 290 };
 291
 292 static struct clk_ops sh_clk_div4_enable_clk_ops = {
 293         .recalc         = sh_clk_div4_recalc,
 294         .set_rate       = sh_clk_div4_set_rate,
 295         .round_rate     = sh_clk_div_round_rate,
 296         .enable         = sh_clk_div4_enable,
 297         .disable        = sh_clk_div4_disable,
 298 };
 299
 300 static struct clk_ops sh_clk_div4_reparent_clk_ops = {
 301         .recalc         = sh_clk_div4_recalc,
 302         .set_rate       = sh_clk_div4_set_rate,
 303         .round_rate     = sh_clk_div_round_rate,
 304         .enable         = sh_clk_div4_enable,
 305         .disable        = sh_clk_div4_disable,
 306         .set_parent     = sh_clk_div4_set_parent,
 307 };
 308
 309 static int __init sh_clk_div4_register_ops(struct clk *clks, int nr,
 310                         struct clk_div4_table *table, struct clk_ops *ops)
 311 {
 312         struct clk *clkp;
 313         void *freq_table;
 314         int nr_divs = table->div_mult_table->nr_divisors;
 315         int freq_table_size = sizeof(struct cpufreq_frequency_table);
 316         int ret = 0;
 317         int k;
 318
 319         freq_table_size *= (nr_divs + 1);
 320         freq_table = kzalloc(freq_table_size * nr, GFP_KERNEL);
 321         if (!freq_table) {
 322                 pr_err("sh_clk_div4_register: unable to alloc memory\n");
 323                 return -ENOMEM;
 324         }
 325
 326         for (k = 0; !ret && (k < nr); k++) {
 327                 clkp = clks + k;
 328
 329                 clkp->ops = ops;
 330                 clkp->priv = table;
 331
 332                 clkp->freq_table = freq_table + (k * freq_table_size);
 333                 clkp->freq_table[nr_divs].frequency = CPUFREQ_TABLE_END;
 334
 335                 ret = clk_register(clkp);
 336         }
 337
 338         return ret;
 339 }
 340
 341 int __init sh_clk_div4_register(struct clk *clks, int nr,
 342                                 struct clk_div4_table *table)
 343 {
 344         return sh_clk_div4_register_ops(clks, nr, table, &sh_clk_div4_clk_ops);
 345 }
 346
 347 int __init sh_clk_div4_enable_register(struct clk *clks, int nr,
 348                                 struct clk_div4_table *table)
 349 {
 350         return sh_clk_div4_register_ops(clks, nr, table,
 351                                         &sh_clk_div4_enable_clk_ops);
 352 }
 353
 354 int __init sh_clk_div4_reparent_register(struct clk *clks, int nr,
 355                                 struct clk_div4_table *table)
 356 {
 357         return sh_clk_div4_register_ops(clks, nr, table,
 358                                         &sh_clk_div4_reparent_clk_ops);
 359 }