drivers/clk/mvebu/cp110-system-controller.c

   1 /*
   2  * Marvell Armada CP110 System Controller
   3  *
   4  * Copyright (C) 2016 Marvell
   5  *
   6  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   7  *
   8  * This file is licensed under the terms of the GNU General Public
   9  * License version 2.  This program is licensed "as is" without any
  10  * warranty of any kind, whether express or implied.
  11  */
  12
  13 /*
  14  * CP110 has 5 core clocks:
  15  *
  16  *  - APLL              (1 Ghz)
  17  *    - PPv2 core       (1/3 APLL)
  18  *    - EIP             (1/2 APLL)
  19  *      - Core          (1/2 EIP)
  20  *
  21  *  - NAND clock, which is either:
  22  *    - Equal to the core clock
  23  *    - 2/5 APLL
  24  *
  25  * CP110 has 32 gatable clocks, for the various peripherals in the
  26  * IP. They have fairly complicated parent/child relationships.
  27  */
  28
  29 #define pr_fmt(fmt) "cp110-system-controller: " fmt
  30
  31 #include <linux/clk-provider.h>
  32 #include <linux/mfd/syscon.h>
  33 #include <linux/module.h>
  34 #include <linux/of.h>
  35 #include <linux/of_address.h>
  36 #include <linux/platform_device.h>
  37 #include <linux/regmap.h>
  38 #include <linux/slab.h>
  39
  40 #define CP110_PM_CLOCK_GATING_REG       0x220
  41 #define CP110_NAND_FLASH_CLK_CTRL_REG   0x700
  42 #define    NF_CLOCK_SEL_400_MASK        BIT(0)
  43
  44 enum {
  45         CP110_CLK_TYPE_CORE,
  46         CP110_CLK_TYPE_GATABLE,
  47 };
  48
  49 #define CP110_MAX_CORE_CLOCKS           5
  50 #define CP110_MAX_GATABLE_CLOCKS        32
  51
  52 #define CP110_CLK_NUM \
  53         (CP110_MAX_CORE_CLOCKS + CP110_MAX_GATABLE_CLOCKS)
  54
  55 #define CP110_CORE_APLL                 0
  56 #define CP110_CORE_PPV2                 1
  57 #define CP110_CORE_EIP                  2
  58 #define CP110_CORE_CORE                 3
  59 #define CP110_CORE_NAND                 4
  60
  61 /* A number of gatable clocks need special handling */
  62 #define CP110_GATE_AUDIO                0
  63 #define CP110_GATE_COMM_UNIT            1
  64 #define CP110_GATE_NAND                 2
  65 #define CP110_GATE_PPV2                 3
  66 #define CP110_GATE_SDIO                 4
  67 #define CP110_GATE_XOR1                 7
  68 #define CP110_GATE_XOR0                 8
  69 #define CP110_GATE_PCIE_X1_0            11
  70 #define CP110_GATE_PCIE_X1_1            12
  71 #define CP110_GATE_PCIE_X4              13
  72 #define CP110_GATE_PCIE_XOR             14
  73 #define CP110_GATE_SATA                 15
  74 #define CP110_GATE_SATA_USB             16
  75 #define CP110_GATE_MAIN                 17
  76 #define CP110_GATE_SDMMC                18
  77 #define CP110_GATE_SLOW_IO              21
  78 #define CP110_GATE_USB3H0               22
  79 #define CP110_GATE_USB3H1               23
  80 #define CP110_GATE_USB3DEV              24
  81 #define CP110_GATE_EIP150               25
  82 #define CP110_GATE_EIP197               26
  83
  84 static struct clk *cp110_clks[CP110_CLK_NUM];
  85
  86 static struct clk_onecell_data cp110_clk_data = {
  87         .clks = cp110_clks,
  88         .clk_num = CP110_CLK_NUM,
  89 };
  90
  91 struct cp110_gate_clk {
  92         struct clk_hw hw;
  93         struct regmap *regmap;
  94         u8 bit_idx;
  95 };
  96
  97 #define to_cp110_gate_clk(clk) container_of(clk, struct cp110_gate_clk, hw)
  98
  99 static int cp110_gate_enable(struct clk_hw *hw)
 100 {
 101         struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
 102
 103         regmap_update_bits(gate->regmap, CP110_PM_CLOCK_GATING_REG,
 104                            BIT(gate->bit_idx), BIT(gate->bit_idx));
 105
 106         return 0;
 107 }
 108
 109 static void cp110_gate_disable(struct clk_hw *hw)
 110 {
 111         struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
 112
 113         regmap_update_bits(gate->regmap, CP110_PM_CLOCK_GATING_REG,
 114                            BIT(gate->bit_idx), 0);
 115 }
 116
 117 static int cp110_gate_is_enabled(struct clk_hw *hw)
 118 {
 119         struct cp110_gate_clk *gate = to_cp110_gate_clk(hw);
 120         u32 val;
 121
 122         regmap_read(gate->regmap, CP110_PM_CLOCK_GATING_REG, &val);
 123
 124         return val & BIT(gate->bit_idx);
 125 }
 126
 127 static const struct clk_ops cp110_gate_ops = {
 128         .enable = cp110_gate_enable,
 129         .disable = cp110_gate_disable,
 130         .is_enabled = cp110_gate_is_enabled,
 131 };
 132
 133 static struct clk *cp110_register_gate(const char *name,
 134                                        const char *parent_name,
 135                                        struct regmap *regmap, u8 bit_idx)
 136 {
 137         struct cp110_gate_clk *gate;
 138         struct clk *clk;
 139         struct clk_init_data init;
 140
 141         gate = kzalloc(sizeof(*gate), GFP_KERNEL);
 142         if (!gate)
 143                 return ERR_PTR(-ENOMEM);
 144
 145         init.name = name;
 146         init.ops = &cp110_gate_ops;
 147         init.parent_names = &parent_name;
 148         init.num_parents = 1;
 149
 150         gate->regmap = regmap;
 151         gate->bit_idx = bit_idx;
 152         gate->hw.init = &init;
 153
 154         clk = clk_register(NULL, &gate->hw);
 155         if (IS_ERR(clk))
 156                 kfree(gate);
 157
 158         return clk;
 159 }
 160
 161 static void cp110_unregister_gate(struct clk *clk)
 162 {
 163         struct clk_hw *hw;
 164
 165         hw = __clk_get_hw(clk);
 166         if (!hw)
 167                 return;
 168
 169         clk_unregister(clk);
 170         kfree(to_cp110_gate_clk(hw));
 171 }
 172
 173 static struct clk *cp110_of_clk_get(struct of_phandle_args *clkspec, void *data)
 174 {
 175         struct clk_onecell_data *clk_data = data;
 176         unsigned int type = clkspec->args[0];
 177         unsigned int idx = clkspec->args[1];
 178
 179         if (type == CP110_CLK_TYPE_CORE) {
 180                 if (idx > CP110_MAX_CORE_CLOCKS)
 181                         return ERR_PTR(-EINVAL);
 182                 return clk_data->clks[idx];
 183         } else if (type == CP110_CLK_TYPE_GATABLE) {
 184                 if (idx > CP110_MAX_GATABLE_CLOCKS)
 185                         return ERR_PTR(-EINVAL);
 186                 return clk_data->clks[CP110_MAX_CORE_CLOCKS + idx];
 187         }
 188
 189         return ERR_PTR(-EINVAL);
 190 }
 191
 192 static int cp110_syscon_clk_probe(struct platform_device *pdev)
 193 {
 194         struct regmap *regmap;
 195         struct device_node *np = pdev->dev.of_node;
 196         const char *ppv2_name, *apll_name, *core_name, *eip_name, *nand_name;
 197         struct clk *clk;
 198         u32 nand_clk_ctrl;
 199         int i, ret;
 200
 201         regmap = syscon_node_to_regmap(np);
 202         if (IS_ERR(regmap))
 203                 return PTR_ERR(regmap);
 204
 205         ret = regmap_read(regmap, CP110_NAND_FLASH_CLK_CTRL_REG,
 206                           &nand_clk_ctrl);
 207         if (ret)
 208                 return ret;
 209
 210         /* Register the APLL which is the root of the clk tree */
 211         of_property_read_string_index(np, "core-clock-output-names",
 212                                       CP110_CORE_APLL, &apll_name);
 213         clk = clk_register_fixed_rate(NULL, apll_name, NULL, 0,
 214                                       1000 * 1000 * 1000);
 215         if (IS_ERR(clk)) {
 216                 ret = PTR_ERR(clk);
 217                 goto fail0;
 218         }
 219
 220         cp110_clks[CP110_CORE_APLL] = clk;
 221
 222         /* PPv2 is APLL/3 */
 223         of_property_read_string_index(np, "core-clock-output-names",
 224                                       CP110_CORE_PPV2, &ppv2_name);
 225         clk = clk_register_fixed_factor(NULL, ppv2_name, apll_name, 0, 1, 3);
 226         if (IS_ERR(clk)) {
 227                 ret = PTR_ERR(clk);
 228                 goto fail1;
 229         }
 230
 231         cp110_clks[CP110_CORE_PPV2] = clk;
 232
 233         /* EIP clock is APLL/2 */
 234         of_property_read_string_index(np, "core-clock-output-names",
 235                                       CP110_CORE_EIP, &eip_name);
 236         clk = clk_register_fixed_factor(NULL, eip_name, apll_name, 0, 1, 2);
 237         if (IS_ERR(clk)) {
 238                 ret = PTR_ERR(clk);
 239                 goto fail2;
 240         }
 241
 242         cp110_clks[CP110_CORE_EIP] = clk;
 243
 244         /* Core clock is EIP/2 */
 245         of_property_read_string_index(np, "core-clock-output-names",
 246                                       CP110_CORE_CORE, &core_name);
 247         clk = clk_register_fixed_factor(NULL, core_name, eip_name, 0, 1, 2);
 248         if (IS_ERR(clk)) {
 249                 ret = PTR_ERR(clk);
 250                 goto fail3;
 251         }
 252
 253         cp110_clks[CP110_CORE_CORE] = clk;
 254
 255         /* NAND can be either APLL/2.5 or core clock */
 256         of_property_read_string_index(np, "core-clock-output-names",
 257                                       CP110_CORE_NAND, &nand_name);
 258         if (nand_clk_ctrl & NF_CLOCK_SEL_400_MASK)
 259                 clk = clk_register_fixed_factor(NULL, nand_name,
 260                                                 apll_name, 0, 2, 5);
 261         else
 262                 clk = clk_register_fixed_factor(NULL, nand_name,
 263                                                 core_name, 0, 1, 1);
 264         if (IS_ERR(clk)) {
 265                 ret = PTR_ERR(clk);
 266                 goto fail4;
 267         }
 268
 269         cp110_clks[CP110_CORE_NAND] = clk;
 270
 271         for (i = 0; i < CP110_MAX_GATABLE_CLOCKS; i++) {
 272                 const char *parent, *name;
 273                 int ret;
 274
 275                 ret = of_property_read_string_index(np,
 276                                                     "gate-clock-output-names",
 277                                                     i, &name);
 278                 /* Reached the end of the list? */
 279                 if (ret < 0)
 280                         break;
 281
 282                 if (!strcmp(name, "none"))
 283                         continue;
 284
 285                 switch (i) {
 286                 case CP110_GATE_AUDIO:
 287                 case CP110_GATE_COMM_UNIT:
 288                 case CP110_GATE_EIP150:
 289                 case CP110_GATE_EIP197:
 290                 case CP110_GATE_SLOW_IO:
 291                         of_property_read_string_index(np,
 292                                                       "gate-clock-output-names",
 293                                                       CP110_GATE_MAIN, &parent);
 294                         break;
 295                 case CP110_GATE_NAND:
 296                         parent = nand_name;
 297                         break;
 298                 case CP110_GATE_PPV2:
 299                         parent = ppv2_name;
 300                         break;
 301                 case CP110_GATE_SDIO:
 302                         of_property_read_string_index(np,
 303                                                       "gate-clock-output-names",
 304                                                       CP110_GATE_SDMMC, &parent);
 305                         break;
 306                 case CP110_GATE_XOR1:
 307                 case CP110_GATE_XOR0:
 308                 case CP110_GATE_PCIE_X1_0:
 309                 case CP110_GATE_PCIE_X1_1:
 310                 case CP110_GATE_PCIE_X4:
 311                         of_property_read_string_index(np,
 312                                                       "gate-clock-output-names",
 313                                                       CP110_GATE_PCIE_XOR, &parent);
 314                         break;
 315                 case CP110_GATE_SATA:
 316                 case CP110_GATE_USB3H0:
 317                 case CP110_GATE_USB3H1:
 318                 case CP110_GATE_USB3DEV:
 319                         of_property_read_string_index(np,
 320                                                       "gate-clock-output-names",
 321                                                       CP110_GATE_SATA_USB, &parent);
 322                         break;
 323                 default:
 324                         parent = core_name;
 325                         break;
 326                 }
 327
 328                 clk = cp110_register_gate(name, parent, regmap, i);
 329                 if (IS_ERR(clk)) {
 330                         ret = PTR_ERR(clk);
 331                         goto fail_gate;
 332                 }
 333
 334                 cp110_clks[CP110_MAX_CORE_CLOCKS + i] = clk;
 335         }
 336
 337         ret = of_clk_add_provider(np, cp110_of_clk_get, &cp110_clk_data);
 338         if (ret)
 339                 goto fail_clk_add;
 340
 341         return 0;
 342
 343 fail_clk_add:
 344 fail_gate:
 345         for (i = 0; i < CP110_MAX_GATABLE_CLOCKS; i++) {
 346                 clk = cp110_clks[CP110_MAX_CORE_CLOCKS + i];
 347
 348                 if (clk)
 349                         cp110_unregister_gate(clk);
 350         }
 351
 352         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_NAND]);
 353 fail4:
 354         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_CORE]);
 355 fail3:
 356         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_EIP]);
 357 fail2:
 358         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_PPV2]);
 359 fail1:
 360         clk_unregister_fixed_rate(cp110_clks[CP110_CORE_APLL]);
 361 fail0:
 362         return ret;
 363 }
 364
 365 static int cp110_syscon_clk_remove(struct platform_device *pdev)
 366 {
 367         int i;
 368
 369         of_clk_del_provider(pdev->dev.of_node);
 370
 371         for (i = 0; i < CP110_MAX_GATABLE_CLOCKS; i++) {
 372                 struct clk *clk = cp110_clks[CP110_MAX_CORE_CLOCKS + i];
 373
 374                 if (clk)
 375                         cp110_unregister_gate(clk);
 376         }
 377
 378         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_NAND]);
 379         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_CORE]);
 380         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_EIP]);
 381         clk_unregister_fixed_factor(cp110_clks[CP110_CORE_PPV2]);
 382         clk_unregister_fixed_rate(cp110_clks[CP110_CORE_APLL]);
 383
 384         return 0;
 385 }
 386
 387 static const struct of_device_id cp110_syscon_of_match[] = {
 388         { .compatible = "marvell,cp110-system-controller0", },
 389         { }
 390 };
 391 MODULE_DEVICE_TABLE(of, armada8k_pcie_of_match);
 392
 393 static struct platform_driver cp110_syscon_driver = {
 394         .probe = cp110_syscon_clk_probe,
 395         .remove = cp110_syscon_clk_remove,
 396         .driver         = {
 397                 .name   = "marvell-cp110-system-controller0",
 398                 .of_match_table = cp110_syscon_of_match,
 399         },
 400 };
 401
 402 module_platform_driver(cp110_syscon_driver);
 403
 404 MODULE_DESCRIPTION("Marvell CP110 System Controller 0 driver");
 405 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>");
 406 MODULE_LICENSE("GPL");