drivers/clk/imx/clk-pllv3.c

   1 /*
   2  * Copyright 2012 Freescale Semiconductor, Inc.
   3  * Copyright 2012 Linaro Ltd.
   4  *
   5  * The code contained herein is licensed under the GNU General Public
   6  * License. You may obtain a copy of the GNU General Public License
   7  * Version 2 or later at the following locations:
   8  *
   9  * http://www.opensource.org/licenses/gpl-license.html
  10  * http://www.gnu.org/copyleft/gpl.html
  11  */
  12
  13 #include <linux/clk-provider.h>
  14 #include <linux/delay.h>
  15 #include <linux/io.h>
  16 #include <linux/slab.h>
  17 #include <linux/jiffies.h>
  18 #include <linux/err.h>
  19 #include "clk.h"
  20
  21 #define PLL_NUM_OFFSET          0x10
  22 #define PLL_DENOM_OFFSET        0x20
  23
  24 #define BM_PLL_POWER            (0x1 << 12)
  25 #define BM_PLL_LOCK             (0x1 << 31)
  26 #define IMX7_ENET_PLL_POWER     (0x1 << 5)
  27
  28 /**
  29  * struct clk_pllv3 - IMX PLL clock version 3
  30  * @clk_hw:      clock source
  31  * @base:        base address of PLL registers
  32  * @powerup_set: set POWER bit to power up the PLL
  33  * @powerdown:   pll powerdown offset bit
  34  * @div_mask:    mask of divider bits
  35  * @div_shift:   shift of divider bits
  36  *
  37  * IMX PLL clock version 3, found on i.MX6 series.  Divider for pllv3
  38  * is actually a multiplier, and always sits at bit 0.
  39  */
  40 struct clk_pllv3 {
  41         struct clk_hw   hw;
  42         void __iomem    *base;
  43         bool            powerup_set;
  44         u32             powerdown;
  45         u32             div_mask;
  46         u32             div_shift;
  47         unsigned long   ref_clock;
  48 };
  49
  50 #define to_clk_pllv3(_hw) container_of(_hw, struct clk_pllv3, hw)
  51
  52 static int clk_pllv3_wait_lock(struct clk_pllv3 *pll)
  53 {
  54         unsigned long timeout = jiffies + msecs_to_jiffies(10);
  55         u32 val = readl_relaxed(pll->base) & pll->powerdown;
  56
  57         /* No need to wait for lock when pll is not powered up */
  58         if ((pll->powerup_set && !val) || (!pll->powerup_set && val))
  59                 return 0;
  60
  61         /* Wait for PLL to lock */
  62         do {
  63                 if (readl_relaxed(pll->base) & BM_PLL_LOCK)
  64                         break;
  65                 if (time_after(jiffies, timeout))
  66                         break;
  67                 usleep_range(50, 500);
  68         } while (1);
  69
  70         return readl_relaxed(pll->base) & BM_PLL_LOCK ? 0 : -ETIMEDOUT;
  71 }
  72
  73 static int clk_pllv3_prepare(struct clk_hw *hw)
  74 {
  75         struct clk_pllv3 *pll = to_clk_pllv3(hw);
  76         u32 val;
  77
  78         val = readl_relaxed(pll->base);
  79         if (pll->powerup_set)
  80                 val |= BM_PLL_POWER;
  81         else
  82                 val &= ~BM_PLL_POWER;
  83         writel_relaxed(val, pll->base);
  84
  85         return clk_pllv3_wait_lock(pll);
  86 }
  87
  88 static void clk_pllv3_unprepare(struct clk_hw *hw)
  89 {
  90         struct clk_pllv3 *pll = to_clk_pllv3(hw);
  91         u32 val;
  92
  93         val = readl_relaxed(pll->base);
  94         if (pll->powerup_set)
  95                 val &= ~BM_PLL_POWER;
  96         else
  97                 val |= BM_PLL_POWER;
  98         writel_relaxed(val, pll->base);
  99 }
 100
 101 static int clk_pllv3_is_prepared(struct clk_hw *hw)
 102 {
 103         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 104
 105         if (readl_relaxed(pll->base) & BM_PLL_LOCK)
 106                 return 1;
 107
 108         return 0;
 109 }
 110
 111 static unsigned long clk_pllv3_recalc_rate(struct clk_hw *hw,
 112                                            unsigned long parent_rate)
 113 {
 114         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 115         u32 div = (readl_relaxed(pll->base) >> pll->div_shift)  & pll->div_mask;
 116
 117         return (div == 1) ? parent_rate * 22 : parent_rate * 20;
 118 }
 119
 120 static long clk_pllv3_round_rate(struct clk_hw *hw, unsigned long rate,
 121                                  unsigned long *prate)
 122 {
 123         unsigned long parent_rate = *prate;
 124
 125         return (rate >= parent_rate * 22) ? parent_rate * 22 :
 126                                             parent_rate * 20;
 127 }
 128
 129 static int clk_pllv3_set_rate(struct clk_hw *hw, unsigned long rate,
 130                 unsigned long parent_rate)
 131 {
 132         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 133         u32 val, div;
 134
 135         if (rate == parent_rate * 22)
 136                 div = 1;
 137         else if (rate == parent_rate * 20)
 138                 div = 0;
 139         else
 140                 return -EINVAL;
 141
 142         val = readl_relaxed(pll->base);
 143         val &= ~(pll->div_mask << pll->div_shift);
 144         val |= (div << pll->div_shift);
 145         writel_relaxed(val, pll->base);
 146
 147         return clk_pllv3_wait_lock(pll);
 148 }
 149
 150 static const struct clk_ops clk_pllv3_ops = {
 151         .prepare        = clk_pllv3_prepare,
 152         .unprepare      = clk_pllv3_unprepare,
 153         .is_prepared    = clk_pllv3_is_prepared,
 154         .recalc_rate    = clk_pllv3_recalc_rate,
 155         .round_rate     = clk_pllv3_round_rate,
 156         .set_rate       = clk_pllv3_set_rate,
 157 };
 158
 159 static unsigned long clk_pllv3_sys_recalc_rate(struct clk_hw *hw,
 160                                                unsigned long parent_rate)
 161 {
 162         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 163         u32 div = readl_relaxed(pll->base) & pll->div_mask;
 164
 165         return parent_rate * div / 2;
 166 }
 167
 168 static long clk_pllv3_sys_round_rate(struct clk_hw *hw, unsigned long rate,
 169                                      unsigned long *prate)
 170 {
 171         unsigned long parent_rate = *prate;
 172         unsigned long min_rate = parent_rate * 54 / 2;
 173         unsigned long max_rate = parent_rate * 108 / 2;
 174         u32 div;
 175
 176         if (rate > max_rate)
 177                 rate = max_rate;
 178         else if (rate < min_rate)
 179                 rate = min_rate;
 180         div = rate * 2 / parent_rate;
 181
 182         return parent_rate * div / 2;
 183 }
 184
 185 static int clk_pllv3_sys_set_rate(struct clk_hw *hw, unsigned long rate,
 186                 unsigned long parent_rate)
 187 {
 188         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 189         unsigned long min_rate = parent_rate * 54 / 2;
 190         unsigned long max_rate = parent_rate * 108 / 2;
 191         u32 val, div;
 192
 193         if (rate < min_rate || rate > max_rate)
 194                 return -EINVAL;
 195
 196         div = rate * 2 / parent_rate;
 197         val = readl_relaxed(pll->base);
 198         val &= ~pll->div_mask;
 199         val |= div;
 200         writel_relaxed(val, pll->base);
 201
 202         return clk_pllv3_wait_lock(pll);
 203 }
 204
 205 static const struct clk_ops clk_pllv3_sys_ops = {
 206         .prepare        = clk_pllv3_prepare,
 207         .unprepare      = clk_pllv3_unprepare,
 208         .is_prepared    = clk_pllv3_is_prepared,
 209         .recalc_rate    = clk_pllv3_sys_recalc_rate,
 210         .round_rate     = clk_pllv3_sys_round_rate,
 211         .set_rate       = clk_pllv3_sys_set_rate,
 212 };
 213
 214 static unsigned long clk_pllv3_av_recalc_rate(struct clk_hw *hw,
 215                                               unsigned long parent_rate)
 216 {
 217         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 218         u32 mfn = readl_relaxed(pll->base + PLL_NUM_OFFSET);
 219         u32 mfd = readl_relaxed(pll->base + PLL_DENOM_OFFSET);
 220         u32 div = readl_relaxed(pll->base) & pll->div_mask;
 221
 222         return (parent_rate * div) + ((parent_rate / mfd) * mfn);
 223 }
 224
 225 static long clk_pllv3_av_round_rate(struct clk_hw *hw, unsigned long rate,
 226                                     unsigned long *prate)
 227 {
 228         unsigned long parent_rate = *prate;
 229         unsigned long min_rate = parent_rate * 27;
 230         unsigned long max_rate = parent_rate * 54;
 231         u32 div;
 232         u32 mfn, mfd = 1000000;
 233         u64 temp64;
 234
 235         if (rate > max_rate)
 236                 rate = max_rate;
 237         else if (rate < min_rate)
 238                 rate = min_rate;
 239
 240         div = rate / parent_rate;
 241         temp64 = (u64) (rate - div * parent_rate);
 242         temp64 *= mfd;
 243         do_div(temp64, parent_rate);
 244         mfn = temp64;
 245
 246         return parent_rate * div + parent_rate / mfd * mfn;
 247 }
 248
 249 static int clk_pllv3_av_set_rate(struct clk_hw *hw, unsigned long rate,
 250                 unsigned long parent_rate)
 251 {
 252         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 253         unsigned long min_rate = parent_rate * 27;
 254         unsigned long max_rate = parent_rate * 54;
 255         u32 val, div;
 256         u32 mfn, mfd = 1000000;
 257         u64 temp64;
 258
 259         if (rate < min_rate || rate > max_rate)
 260                 return -EINVAL;
 261
 262         div = rate / parent_rate;
 263         temp64 = (u64) (rate - div * parent_rate);
 264         temp64 *= mfd;
 265         do_div(temp64, parent_rate);
 266         mfn = temp64;
 267
 268         val = readl_relaxed(pll->base);
 269         val &= ~pll->div_mask;
 270         val |= div;
 271         writel_relaxed(val, pll->base);
 272         writel_relaxed(mfn, pll->base + PLL_NUM_OFFSET);
 273         writel_relaxed(mfd, pll->base + PLL_DENOM_OFFSET);
 274
 275         return clk_pllv3_wait_lock(pll);
 276 }
 277
 278 static const struct clk_ops clk_pllv3_av_ops = {
 279         .prepare        = clk_pllv3_prepare,
 280         .unprepare      = clk_pllv3_unprepare,
 281         .is_prepared    = clk_pllv3_is_prepared,
 282         .recalc_rate    = clk_pllv3_av_recalc_rate,
 283         .round_rate     = clk_pllv3_av_round_rate,
 284         .set_rate       = clk_pllv3_av_set_rate,
 285 };
 286
 287 static unsigned long clk_pllv3_enet_recalc_rate(struct clk_hw *hw,
 288                                                 unsigned long parent_rate)
 289 {
 290         struct clk_pllv3 *pll = to_clk_pllv3(hw);
 291
 292         return pll->ref_clock;
 293 }
 294
 295 static const struct clk_ops clk_pllv3_enet_ops = {
 296         .prepare        = clk_pllv3_prepare,
 297         .unprepare      = clk_pllv3_unprepare,
 298         .is_prepared    = clk_pllv3_is_prepared,
 299         .recalc_rate    = clk_pllv3_enet_recalc_rate,
 300 };
 301
 302 struct clk *imx_clk_pllv3(enum imx_pllv3_type type, const char *name,
 303                           const char *parent_name, void __iomem *base,
 304                           u32 div_mask)
 305 {
 306         struct clk_pllv3 *pll;
 307         const struct clk_ops *ops;
 308         struct clk *clk;
 309         struct clk_init_data init;
 310
 311         pll = kzalloc(sizeof(*pll), GFP_KERNEL);
 312         if (!pll)
 313                 return ERR_PTR(-ENOMEM);
 314
 315         pll->powerdown = BM_PLL_POWER;
 316
 317         switch (type) {
 318         case IMX_PLLV3_SYS:
 319                 ops = &clk_pllv3_sys_ops;
 320                 break;
 321         case IMX_PLLV3_USB_VF610:
 322                 pll->div_shift = 1;
 323         case IMX_PLLV3_USB:
 324                 ops = &clk_pllv3_ops;
 325                 pll->powerup_set = true;
 326                 break;
 327         case IMX_PLLV3_AV:
 328                 ops = &clk_pllv3_av_ops;
 329                 break;
 330         case IMX_PLLV3_ENET_IMX7:
 331                 pll->powerdown = IMX7_ENET_PLL_POWER;
 332                 pll->ref_clock = 1000000000;
 333                 ops = &clk_pllv3_enet_ops;
 334                 break;
 335         case IMX_PLLV3_ENET:
 336                 pll->ref_clock = 500000000;
 337                 ops = &clk_pllv3_enet_ops;
 338                 break;
 339         default:
 340                 ops = &clk_pllv3_ops;
 341         }
 342         pll->base = base;
 343         pll->div_mask = div_mask;
 344
 345         init.name = name;
 346         init.ops = ops;
 347         init.flags = 0;
 348         init.parent_names = &parent_name;
 349         init.num_parents = 1;
 350
 351         pll->hw.init = &init;
 352
 353         clk = clk_register(NULL, &pll->hw);
 354         if (IS_ERR(clk))
 355                 kfree(pll);
 356
 357         return clk;
 358 }