drivers/clk/mvebu/kirkwood.c

   1 /*
   2  * Marvell Kirkwood SoC clocks
   3  *
   4  * Copyright (C) 2012 Marvell
   5  *
   6  * Gregory CLEMENT <gregory.clement@free-electrons.com>
   7  * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
   8  * Andrew Lunn <andrew@lunn.ch>
   9  *
  10  * This file is licensed under the terms of the GNU General Public
  11  * License version 2.  This program is licensed "as is" without any
  12  * warranty of any kind, whether express or implied.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/slab.h>
  17 #include <linux/clk-provider.h>
  18 #include <linux/io.h>
  19 #include <linux/of.h>
  20 #include <linux/of_address.h>
  21 #include "common.h"
  22
  23 /*
  24  * Core Clocks
  25  *
  26  * Kirkwood PLL sample-at-reset configuration
  27  * (6180 has different SAR layout than other Kirkwood SoCs)
  28  *
  29  * SAR0[4:3,22,1] : CPU frequency (6281,6292,6282)
  30  *      4  =  600 MHz
  31  *      6  =  800 MHz
  32  *      7  = 1000 MHz
  33  *      9  = 1200 MHz
  34  *      12 = 1500 MHz
  35  *      13 = 1600 MHz
  36  *      14 = 1800 MHz
  37  *      15 = 2000 MHz
  38  *      others reserved.
  39  *
  40  * SAR0[19,10:9] : CPU to L2 Clock divider ratio (6281,6292,6282)
  41  *      1 = (1/2) * CPU
  42  *      3 = (1/3) * CPU
  43  *      5 = (1/4) * CPU
  44  *      others reserved.
  45  *
  46  * SAR0[8:5] : CPU to DDR DRAM Clock divider ratio (6281,6292,6282)
  47  *      2 = (1/2) * CPU
  48  *      4 = (1/3) * CPU
  49  *      6 = (1/4) * CPU
  50  *      7 = (2/9) * CPU
  51  *      8 = (1/5) * CPU
  52  *      9 = (1/6) * CPU
  53  *      others reserved.
  54  *
  55  * SAR0[4:2] : Kirkwood 6180 cpu/l2/ddr clock configuration (6180 only)
  56  *      5 = [CPU =  600 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/3) * CPU]
  57  *      6 = [CPU =  800 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/4) * CPU]
  58  *      7 = [CPU = 1000 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/5) * CPU]
  59  *      others reserved.
  60  *
  61  * SAR0[21] : TCLK frequency
  62  *      0 = 200 MHz
  63  *      1 = 166 MHz
  64  *      others reserved.
  65  */
  66
  67 #define SAR_KIRKWOOD_CPU_FREQ(x)        \
  68         (((x & (1 <<  1)) >>  1) |      \
  69          ((x & (1 << 22)) >> 21) |      \
  70          ((x & (3 <<  3)) >>  1))
  71 #define SAR_KIRKWOOD_L2_RATIO(x)        \
  72         (((x & (3 <<  9)) >> 9) |       \
  73          (((x & (1 << 19)) >> 17)))
  74 #define SAR_KIRKWOOD_DDR_RATIO          5
  75 #define SAR_KIRKWOOD_DDR_RATIO_MASK     0xf
  76 #define SAR_MV88F6180_CLK               2
  77 #define SAR_MV88F6180_CLK_MASK          0x7
  78 #define SAR_KIRKWOOD_TCLK_FREQ          21
  79 #define SAR_KIRKWOOD_TCLK_FREQ_MASK     0x1
  80
  81 enum { KIRKWOOD_CPU_TO_L2, KIRKWOOD_CPU_TO_DDR };
  82
  83 static const struct coreclk_ratio kirkwood_coreclk_ratios[] __initconst = {
  84         { .id = KIRKWOOD_CPU_TO_L2, .name = "l2clk", },
  85         { .id = KIRKWOOD_CPU_TO_DDR, .name = "ddrclk", }
  86 };
  87
  88 static u32 __init kirkwood_get_tclk_freq(void __iomem *sar)
  89 {
  90         u32 opt = (readl(sar) >> SAR_KIRKWOOD_TCLK_FREQ) &
  91                 SAR_KIRKWOOD_TCLK_FREQ_MASK;
  92         return (opt) ? 166666667 : 200000000;
  93 }
  94
  95 static const u32 kirkwood_cpu_freqs[] __initconst = {
  96         0, 0, 0, 0,
  97         600000000,
  98         0,
  99         800000000,
 100         1000000000,
 101         0,
 102         1200000000,
 103         0, 0,
 104         1500000000,
 105         1600000000,
 106         1800000000,
 107         2000000000
 108 };
 109
 110 static u32 __init kirkwood_get_cpu_freq(void __iomem *sar)
 111 {
 112         u32 opt = SAR_KIRKWOOD_CPU_FREQ(readl(sar));
 113         return kirkwood_cpu_freqs[opt];
 114 }
 115
 116 static const int kirkwood_cpu_l2_ratios[8][2] __initconst = {
 117         { 0, 1 }, { 1, 2 }, { 0, 1 }, { 1, 3 },
 118         { 0, 1 }, { 1, 4 }, { 0, 1 }, { 0, 1 }
 119 };
 120
 121 static const int kirkwood_cpu_ddr_ratios[16][2] __initconst = {
 122         { 0, 1 }, { 0, 1 }, { 1, 2 }, { 0, 1 },
 123         { 1, 3 }, { 0, 1 }, { 1, 4 }, { 2, 9 },
 124         { 1, 5 }, { 1, 6 }, { 0, 1 }, { 0, 1 },
 125         { 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 }
 126 };
 127
 128 static void __init kirkwood_get_clk_ratio(
 129         void __iomem *sar, int id, int *mult, int *div)
 130 {
 131         switch (id) {
 132         case KIRKWOOD_CPU_TO_L2:
 133         {
 134                 u32 opt = SAR_KIRKWOOD_L2_RATIO(readl(sar));
 135                 *mult = kirkwood_cpu_l2_ratios[opt][0];
 136                 *div = kirkwood_cpu_l2_ratios[opt][1];
 137                 break;
 138         }
 139         case KIRKWOOD_CPU_TO_DDR:
 140         {
 141                 u32 opt = (readl(sar) >> SAR_KIRKWOOD_DDR_RATIO) &
 142                         SAR_KIRKWOOD_DDR_RATIO_MASK;
 143                 *mult = kirkwood_cpu_ddr_ratios[opt][0];
 144                 *div = kirkwood_cpu_ddr_ratios[opt][1];
 145                 break;
 146         }
 147         }
 148 }
 149
 150 static const u32 mv88f6180_cpu_freqs[] __initconst = {
 151         0, 0, 0, 0, 0,
 152         600000000,
 153         800000000,
 154         1000000000
 155 };
 156
 157 static u32 __init mv88f6180_get_cpu_freq(void __iomem *sar)
 158 {
 159         u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) & SAR_MV88F6180_CLK_MASK;
 160         return mv88f6180_cpu_freqs[opt];
 161 }
 162
 163 static const int mv88f6180_cpu_ddr_ratios[8][2] __initconst = {
 164         { 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 },
 165         { 0, 1 }, { 1, 3 }, { 1, 4 }, { 1, 5 }
 166 };
 167
 168 static void __init mv88f6180_get_clk_ratio(
 169         void __iomem *sar, int id, int *mult, int *div)
 170 {
 171         switch (id) {
 172         case KIRKWOOD_CPU_TO_L2:
 173         {
 174                 /* mv88f6180 has a fixed 1:2 CPU-to-L2 ratio */
 175                 *mult = 1;
 176                 *div = 2;
 177                 break;
 178         }
 179         case KIRKWOOD_CPU_TO_DDR:
 180         {
 181                 u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) &
 182                         SAR_MV88F6180_CLK_MASK;
 183                 *mult = mv88f6180_cpu_ddr_ratios[opt][0];
 184                 *div = mv88f6180_cpu_ddr_ratios[opt][1];
 185                 break;
 186         }
 187         }
 188 }
 189
 190 static const struct coreclk_soc_desc kirkwood_coreclks = {
 191         .get_tclk_freq = kirkwood_get_tclk_freq,
 192         .get_cpu_freq = kirkwood_get_cpu_freq,
 193         .get_clk_ratio = kirkwood_get_clk_ratio,
 194         .ratios = kirkwood_coreclk_ratios,
 195         .num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
 196 };
 197
 198 static const struct coreclk_soc_desc mv88f6180_coreclks = {
 199         .get_tclk_freq = kirkwood_get_tclk_freq,
 200         .get_cpu_freq = mv88f6180_get_cpu_freq,
 201         .get_clk_ratio = mv88f6180_get_clk_ratio,
 202         .ratios = kirkwood_coreclk_ratios,
 203         .num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
 204 };
 205
 206 /*
 207  * Clock Gating Control
 208  */
 209
 210 static const struct clk_gating_soc_desc kirkwood_gating_desc[] __initconst = {
 211         { "ge0", NULL, 0, 0 },
 212         { "pex0", NULL, 2, 0 },
 213         { "usb0", NULL, 3, 0 },
 214         { "sdio", NULL, 4, 0 },
 215         { "tsu", NULL, 5, 0 },
 216         { "runit", NULL, 7, 0 },
 217         { "xor0", NULL, 8, 0 },
 218         { "audio", NULL, 9, 0 },
 219         { "sata0", NULL, 14, 0 },
 220         { "sata1", NULL, 15, 0 },
 221         { "xor1", NULL, 16, 0 },
 222         { "crypto", NULL, 17, 0 },
 223         { "pex1", NULL, 18, 0 },
 224         { "ge1", NULL, 19, 0 },
 225         { "tdm", NULL, 20, 0 },
 226         { }
 227 };
 228
 229
 230 /*
 231  * Clock Muxing Control
 232  */
 233
 234 struct clk_muxing_soc_desc {
 235         const char *name;
 236         const char **parents;
 237         int num_parents;
 238         int shift;
 239         int width;
 240         unsigned long flags;
 241 };
 242
 243 struct clk_muxing_ctrl {
 244         spinlock_t *lock;
 245         struct clk **muxes;
 246         int num_muxes;
 247 };
 248
 249 static const char *powersave_parents[] = {
 250         "cpuclk",
 251         "ddrclk",
 252 };
 253
 254 static const struct clk_muxing_soc_desc kirkwood_mux_desc[] __initconst = {
 255         { "powersave", powersave_parents, ARRAY_SIZE(powersave_parents),
 256                 11, 1, 0 },
 257 };
 258
 259 static struct clk *clk_muxing_get_src(
 260         struct of_phandle_args *clkspec, void *data)
 261 {
 262         struct clk_muxing_ctrl *ctrl = (struct clk_muxing_ctrl *)data;
 263         int n;
 264
 265         if (clkspec->args_count < 1)
 266                 return ERR_PTR(-EINVAL);
 267
 268         for (n = 0; n < ctrl->num_muxes; n++) {
 269                 struct clk_mux *mux =
 270                         to_clk_mux(__clk_get_hw(ctrl->muxes[n]));
 271                 if (clkspec->args[0] == mux->shift)
 272                         return ctrl->muxes[n];
 273         }
 274         return ERR_PTR(-ENODEV);
 275 }
 276
 277 static void __init kirkwood_clk_muxing_setup(struct device_node *np,
 278                                    const struct clk_muxing_soc_desc *desc)
 279 {
 280         struct clk_muxing_ctrl *ctrl;
 281         void __iomem *base;
 282         int n;
 283
 284         base = of_iomap(np, 0);
 285         if (WARN_ON(!base))
 286                 return;
 287
 288         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 289         if (WARN_ON(!ctrl))
 290                 goto ctrl_out;
 291
 292         /* lock must already be initialized */
 293         ctrl->lock = &ctrl_gating_lock;
 294
 295         /* Count, allocate, and register clock muxes */
 296         for (n = 0; desc[n].name;)
 297                 n++;
 298
 299         ctrl->num_muxes = n;
 300         ctrl->muxes = kcalloc(ctrl->num_muxes, sizeof(struct clk *),
 301                         GFP_KERNEL);
 302         if (WARN_ON(!ctrl->muxes))
 303                 goto muxes_out;
 304
 305         for (n = 0; n < ctrl->num_muxes; n++) {
 306                 ctrl->muxes[n] = clk_register_mux(NULL, desc[n].name,
 307                                 desc[n].parents, desc[n].num_parents,
 308                                 desc[n].flags, base, desc[n].shift,
 309                                 desc[n].width, desc[n].flags, ctrl->lock);
 310                 WARN_ON(IS_ERR(ctrl->muxes[n]));
 311         }
 312
 313         of_clk_add_provider(np, clk_muxing_get_src, ctrl);
 314
 315         return;
 316 muxes_out:
 317         kfree(ctrl);
 318 ctrl_out:
 319         iounmap(base);
 320 }
 321
 322 static void __init kirkwood_clk_init(struct device_node *np)
 323 {
 324         struct device_node *cgnp =
 325                 of_find_compatible_node(NULL, NULL, "marvell,kirkwood-gating-clock");
 326
 327
 328         if (of_device_is_compatible(np, "marvell,mv88f6180-core-clock"))
 329                 mvebu_coreclk_setup(np, &mv88f6180_coreclks);
 330         else
 331                 mvebu_coreclk_setup(np, &kirkwood_coreclks);
 332
 333         if (cgnp) {
 334                 mvebu_clk_gating_setup(cgnp, kirkwood_gating_desc);
 335                 kirkwood_clk_muxing_setup(cgnp, kirkwood_mux_desc);
 336         }
 337 }
 338 CLK_OF_DECLARE(kirkwood_clk, "marvell,kirkwood-core-clock",
 339                kirkwood_clk_init);
 340 CLK_OF_DECLARE(mv88f6180_clk, "marvell,mv88f6180-core-clock",
 341                kirkwood_clk_init);