arch/arm/mach-omap2/cm2xxx.c

   1 /*
   2  * OMAP2xxx CM module functions
   3  *
   4  * Copyright (C) 2009 Nokia Corporation
   5  * Copyright (C) 2008-2010, 2012 Texas Instruments, Inc.
   6  * Paul Walmsley
   7  * Rajendra Nayak <rnayak@ti.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/types.h>
  16 #include <linux/delay.h>
  17 #include <linux/errno.h>
  18 #include <linux/err.h>
  19 #include <linux/io.h>
  20
  21 #include "soc.h"
  22 #include "iomap.h"
  23 #include "common.h"
  24 #include "prm2xxx.h"
  25 #include "cm.h"
  26 #include "cm2xxx.h"
  27 #include "cm-regbits-24xx.h"
  28 #include "clockdomain.h"
  29
  30 /* CM_AUTOIDLE_PLL.AUTO_* bit values for DPLLs */
  31 #define DPLL_AUTOIDLE_DISABLE                           0x0
  32 #define OMAP2XXX_DPLL_AUTOIDLE_LOW_POWER_STOP           0x3
  33
  34 /* CM_AUTOIDLE_PLL.AUTO_* bit values for APLLs (OMAP2xxx only) */
  35 #define OMAP2XXX_APLL_AUTOIDLE_DISABLE                  0x0
  36 #define OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP           0x3
  37
  38 /* CM_IDLEST_PLL bit value offset for APLLs (OMAP2xxx only) */
  39 #define EN_APLL_LOCKED                                  3
  40
  41 static const u8 omap2xxx_cm_idlest_offs[] = {
  42         CM_IDLEST1, CM_IDLEST2, OMAP2430_CM_IDLEST3, OMAP24XX_CM_IDLEST4
  43 };
  44
  45 /*
  46  *
  47  */
  48
  49 static void _write_clktrctrl(u8 c, s16 module, u32 mask)
  50 {
  51         u32 v;
  52
  53         v = omap2_cm_read_mod_reg(module, OMAP2_CM_CLKSTCTRL);
  54         v &= ~mask;
  55         v |= c << __ffs(mask);
  56         omap2_cm_write_mod_reg(v, module, OMAP2_CM_CLKSTCTRL);
  57 }
  58
  59 bool omap2xxx_cm_is_clkdm_in_hwsup(s16 module, u32 mask)
  60 {
  61         u32 v;
  62
  63         v = omap2_cm_read_mod_reg(module, OMAP2_CM_CLKSTCTRL);
  64         v &= mask;
  65         v >>= __ffs(mask);
  66
  67         return (v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO) ? 1 : 0;
  68 }
  69
  70 void omap2xxx_cm_clkdm_enable_hwsup(s16 module, u32 mask)
  71 {
  72         _write_clktrctrl(OMAP24XX_CLKSTCTRL_ENABLE_AUTO, module, mask);
  73 }
  74
  75 void omap2xxx_cm_clkdm_disable_hwsup(s16 module, u32 mask)
  76 {
  77         _write_clktrctrl(OMAP24XX_CLKSTCTRL_DISABLE_AUTO, module, mask);
  78 }
  79
  80 /*
  81  * DPLL autoidle control
  82  */
  83
  84 static void _omap2xxx_set_dpll_autoidle(u8 m)
  85 {
  86         u32 v;
  87
  88         v = omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE);
  89         v &= ~OMAP24XX_AUTO_DPLL_MASK;
  90         v |= m << OMAP24XX_AUTO_DPLL_SHIFT;
  91         omap2_cm_write_mod_reg(v, PLL_MOD, CM_AUTOIDLE);
  92 }
  93
  94 void omap2xxx_cm_set_dpll_disable_autoidle(void)
  95 {
  96         _omap2xxx_set_dpll_autoidle(OMAP2XXX_DPLL_AUTOIDLE_LOW_POWER_STOP);
  97 }
  98
  99 void omap2xxx_cm_set_dpll_auto_low_power_stop(void)
 100 {
 101         _omap2xxx_set_dpll_autoidle(DPLL_AUTOIDLE_DISABLE);
 102 }
 103
 104 /*
 105  * APLL control
 106  */
 107
 108 static void _omap2xxx_set_apll_autoidle(u8 m, u32 mask)
 109 {
 110         u32 v;
 111
 112         v = omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE);
 113         v &= ~mask;
 114         v |= m << __ffs(mask);
 115         omap2_cm_write_mod_reg(v, PLL_MOD, CM_AUTOIDLE);
 116 }
 117
 118 void omap2xxx_cm_set_apll54_disable_autoidle(void)
 119 {
 120         _omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP,
 121                                     OMAP24XX_AUTO_54M_MASK);
 122 }
 123
 124 void omap2xxx_cm_set_apll54_auto_low_power_stop(void)
 125 {
 126         _omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_DISABLE,
 127                                     OMAP24XX_AUTO_54M_MASK);
 128 }
 129
 130 void omap2xxx_cm_set_apll96_disable_autoidle(void)
 131 {
 132         _omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP,
 133                                     OMAP24XX_AUTO_96M_MASK);
 134 }
 135
 136 void omap2xxx_cm_set_apll96_auto_low_power_stop(void)
 137 {
 138         _omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_DISABLE,
 139                                     OMAP24XX_AUTO_96M_MASK);
 140 }
 141
 142 /* Enable an APLL if off */
 143 static int _omap2xxx_apll_enable(u8 enable_bit, u8 status_bit)
 144 {
 145         u32 v, m;
 146
 147         m = EN_APLL_LOCKED << enable_bit;
 148
 149         v = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKEN);
 150         if (v & m)
 151                 return 0;   /* apll already enabled */
 152
 153         v |= m;
 154         omap2_cm_write_mod_reg(v, PLL_MOD, CM_CLKEN);
 155
 156         omap2xxx_cm_wait_module_ready(PLL_MOD, 1, status_bit);
 157
 158         /*
 159          * REVISIT: Should we return an error code if
 160          * omap2xxx_cm_wait_module_ready() fails?
 161          */
 162         return 0;
 163 }
 164
 165 /* Stop APLL */
 166 static void _omap2xxx_apll_disable(u8 enable_bit)
 167 {
 168         u32 v;
 169
 170         v = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKEN);
 171         v &= ~(EN_APLL_LOCKED << enable_bit);
 172         omap2_cm_write_mod_reg(v, PLL_MOD, CM_CLKEN);
 173 }
 174
 175 /* Enable an APLL if off */
 176 int omap2xxx_cm_apll54_enable(void)
 177 {
 178         return _omap2xxx_apll_enable(OMAP24XX_EN_54M_PLL_SHIFT,
 179                                      OMAP24XX_ST_54M_APLL_SHIFT);
 180 }
 181
 182 /* Enable an APLL if off */
 183 int omap2xxx_cm_apll96_enable(void)
 184 {
 185         return _omap2xxx_apll_enable(OMAP24XX_EN_96M_PLL_SHIFT,
 186                                      OMAP24XX_ST_96M_APLL_SHIFT);
 187 }
 188
 189 /* Stop APLL */
 190 void omap2xxx_cm_apll54_disable(void)
 191 {
 192         _omap2xxx_apll_disable(OMAP24XX_EN_54M_PLL_SHIFT);
 193 }
 194
 195 /* Stop APLL */
 196 void omap2xxx_cm_apll96_disable(void)
 197 {
 198         _omap2xxx_apll_disable(OMAP24XX_EN_96M_PLL_SHIFT);
 199 }
 200
 201 /**
 202  * omap2xxx_cm_split_idlest_reg - split CM_IDLEST reg addr into its components
 203  * @idlest_reg: CM_IDLEST* virtual address
 204  * @prcm_inst: pointer to an s16 to return the PRCM instance offset
 205  * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
 206  *
 207  * XXX This function is only needed until absolute register addresses are
 208  * removed from the OMAP struct clk records.
 209  */
 210 int omap2xxx_cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
 211                                  u8 *idlest_reg_id)
 212 {
 213         unsigned long offs;
 214         u8 idlest_offs;
 215         int i;
 216
 217         if (idlest_reg < cm_base || idlest_reg > (cm_base + 0x0fff))
 218                 return -EINVAL;
 219
 220         idlest_offs = (unsigned long)idlest_reg & 0xff;
 221         for (i = 0; i < ARRAY_SIZE(omap2xxx_cm_idlest_offs); i++) {
 222                 if (idlest_offs == omap2xxx_cm_idlest_offs[i]) {
 223                         *idlest_reg_id = i + 1;
 224                         break;
 225                 }
 226         }
 227
 228         if (i == ARRAY_SIZE(omap2xxx_cm_idlest_offs))
 229                 return -EINVAL;
 230
 231         offs = idlest_reg - cm_base;
 232         offs &= 0xff00;
 233         *prcm_inst = offs;
 234
 235         return 0;
 236 }
 237
 238 /*
 239  *
 240  */
 241
 242 /**
 243  * omap2xxx_cm_wait_module_ready - wait for a module to leave idle or standby
 244  * @prcm_mod: PRCM module offset
 245  * @idlest_id: CM_IDLESTx register ID (i.e., x = 1, 2, 3)
 246  * @idlest_shift: shift of the bit in the CM_IDLEST* register to check
 247  *
 248  * Wait for the PRCM to indicate that the module identified by
 249  * (@prcm_mod, @idlest_id, @idlest_shift) is clocked.  Return 0 upon
 250  * success or -EBUSY if the module doesn't enable in time.
 251  */
 252 int omap2xxx_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
 253 {
 254         int ena = 0, i = 0;
 255         u8 cm_idlest_reg;
 256         u32 mask;
 257
 258         if (!idlest_id || (idlest_id > ARRAY_SIZE(omap2xxx_cm_idlest_offs)))
 259                 return -EINVAL;
 260
 261         cm_idlest_reg = omap2xxx_cm_idlest_offs[idlest_id - 1];
 262
 263         mask = 1 << idlest_shift;
 264         ena = mask;
 265
 266         omap_test_timeout(((omap2_cm_read_mod_reg(prcm_mod, cm_idlest_reg) &
 267                             mask) == ena), MAX_MODULE_READY_TIME, i);
 268
 269         return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
 270 }
 271
 272 /* Clockdomain low-level functions */
 273
 274 static void omap2xxx_clkdm_allow_idle(struct clockdomain *clkdm)
 275 {
 276         if (atomic_read(&clkdm->usecount) > 0)
 277                 _clkdm_add_autodeps(clkdm);
 278
 279         omap2xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 280                                        clkdm->clktrctrl_mask);
 281 }
 282
 283 static void omap2xxx_clkdm_deny_idle(struct clockdomain *clkdm)
 284 {
 285         omap2xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 286                                         clkdm->clktrctrl_mask);
 287
 288         if (atomic_read(&clkdm->usecount) > 0)
 289                 _clkdm_del_autodeps(clkdm);
 290 }
 291
 292 static int omap2xxx_clkdm_clk_enable(struct clockdomain *clkdm)
 293 {
 294         bool hwsup = false;
 295
 296         if (!clkdm->clktrctrl_mask)
 297                 return 0;
 298
 299         hwsup = omap2xxx_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 300                                               clkdm->clktrctrl_mask);
 301
 302         if (hwsup) {
 303                 /* Disable HW transitions when we are changing deps */
 304                 omap2xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 305                                                 clkdm->clktrctrl_mask);
 306                 _clkdm_add_autodeps(clkdm);
 307                 omap2xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 308                                                clkdm->clktrctrl_mask);
 309         } else {
 310                 if (clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)
 311                         omap2xxx_clkdm_wakeup(clkdm);
 312         }
 313
 314         return 0;
 315 }
 316
 317 static int omap2xxx_clkdm_clk_disable(struct clockdomain *clkdm)
 318 {
 319         bool hwsup = false;
 320
 321         if (!clkdm->clktrctrl_mask)
 322                 return 0;
 323
 324         hwsup = omap2xxx_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 325                                               clkdm->clktrctrl_mask);
 326
 327         if (hwsup) {
 328                 /* Disable HW transitions when we are changing deps */
 329                 omap2xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 330                                                 clkdm->clktrctrl_mask);
 331                 _clkdm_del_autodeps(clkdm);
 332                 omap2xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
 333                                                clkdm->clktrctrl_mask);
 334         } else {
 335                 if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP)
 336                         omap2xxx_clkdm_sleep(clkdm);
 337         }
 338
 339         return 0;
 340 }
 341
 342 struct clkdm_ops omap2_clkdm_operations = {
 343         .clkdm_add_wkdep        = omap2_clkdm_add_wkdep,
 344         .clkdm_del_wkdep        = omap2_clkdm_del_wkdep,
 345         .clkdm_read_wkdep       = omap2_clkdm_read_wkdep,
 346         .clkdm_clear_all_wkdeps = omap2_clkdm_clear_all_wkdeps,
 347         .clkdm_sleep            = omap2xxx_clkdm_sleep,
 348         .clkdm_wakeup           = omap2xxx_clkdm_wakeup,
 349         .clkdm_allow_idle       = omap2xxx_clkdm_allow_idle,
 350         .clkdm_deny_idle        = omap2xxx_clkdm_deny_idle,
 351         .clkdm_clk_enable       = omap2xxx_clkdm_clk_enable,
 352         .clkdm_clk_disable      = omap2xxx_clkdm_clk_disable,
 353 };
 354
 355 /*
 356  *
 357  */
 358
 359 static struct cm_ll_data omap2xxx_cm_ll_data = {
 360         .split_idlest_reg       = &omap2xxx_cm_split_idlest_reg,
 361         .wait_module_ready      = &omap2xxx_cm_wait_module_ready,
 362 };
 363
 364 int __init omap2xxx_cm_init(void)
 365 {
 366         if (!cpu_is_omap24xx())
 367                 return 0;
 368
 369         return cm_register(&omap2xxx_cm_ll_data);
 370 }
 371
 372 static void __exit omap2xxx_cm_exit(void)
 373 {
 374         if (!cpu_is_omap24xx())
 375                 return;
 376
 377         /* Should never happen */
 378         WARN(cm_unregister(&omap2xxx_cm_ll_data),
 379              "%s: cm_ll_data function pointer mismatch\n", __func__);
 380 }
 381 __exitcall(omap2xxx_cm_exit);