arch/arm/mach-omap2/prm33xx.c

   1 /*
   2  * AM33XX PRM functions
   3  *
   4  * Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation version 2.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether express or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/types.h>
  18 #include <linux/errno.h>
  19 #include <linux/err.h>
  20 #include <linux/io.h>
  21
  22 #include "powerdomain.h"
  23 #include "prm33xx.h"
  24 #include "prm-regbits-33xx.h"
  25
  26 /* Read a register in a PRM instance */
  27 u32 am33xx_prm_read_reg(s16 inst, u16 idx)
  28 {
  29         return readl_relaxed(prm_base + inst + idx);
  30 }
  31
  32 /* Write into a register in a PRM instance */
  33 void am33xx_prm_write_reg(u32 val, s16 inst, u16 idx)
  34 {
  35         writel_relaxed(val, prm_base + inst + idx);
  36 }
  37
  38 /* Read-modify-write a register in PRM. Caller must lock */
  39 u32 am33xx_prm_rmw_reg_bits(u32 mask, u32 bits, s16 inst, s16 idx)
  40 {
  41         u32 v;
  42
  43         v = am33xx_prm_read_reg(inst, idx);
  44         v &= ~mask;
  45         v |= bits;
  46         am33xx_prm_write_reg(v, inst, idx);
  47
  48         return v;
  49 }
  50
  51 /**
  52  * am33xx_prm_is_hardreset_asserted - read the HW reset line state of
  53  * submodules contained in the hwmod module
  54  * @shift: register bit shift corresponding to the reset line to check
  55  * @inst: CM instance register offset (*_INST macro)
  56  * @rstctrl_offs: RM_RSTCTRL register address offset for this module
  57  *
  58  * Returns 1 if the (sub)module hardreset line is currently asserted,
  59  * 0 if the (sub)module hardreset line is not currently asserted, or
  60  * -EINVAL upon parameter error.
  61  */
  62 int am33xx_prm_is_hardreset_asserted(u8 shift, s16 inst, u16 rstctrl_offs)
  63 {
  64         u32 v;
  65
  66         v = am33xx_prm_read_reg(inst, rstctrl_offs);
  67         v &= 1 << shift;
  68         v >>= shift;
  69
  70         return v;
  71 }
  72
  73 /**
  74  * am33xx_prm_assert_hardreset - assert the HW reset line of a submodule
  75  * @shift: register bit shift corresponding to the reset line to assert
  76  * @inst: CM instance register offset (*_INST macro)
  77  * @rstctrl_reg: RM_RSTCTRL register address for this module
  78  *
  79  * Some IPs like dsp, ipu or iva contain processors that require an HW
  80  * reset line to be asserted / deasserted in order to fully enable the
  81  * IP.  These modules may have multiple hard-reset lines that reset
  82  * different 'submodules' inside the IP block.  This function will
  83  * place the submodule into reset.  Returns 0 upon success or -EINVAL
  84  * upon an argument error.
  85  */
  86 int am33xx_prm_assert_hardreset(u8 shift, s16 inst, u16 rstctrl_offs)
  87 {
  88         u32 mask = 1 << shift;
  89
  90         am33xx_prm_rmw_reg_bits(mask, mask, inst, rstctrl_offs);
  91
  92         return 0;
  93 }
  94
  95 /**
  96  * am33xx_prm_deassert_hardreset - deassert a submodule hardreset line and
  97  * wait
  98  * @shift: register bit shift corresponding to the reset line to deassert
  99  * @inst: CM instance register offset (*_INST macro)
 100  * @rstctrl_reg: RM_RSTCTRL register address for this module
 101  * @rstst_reg: RM_RSTST register address for this module
 102  *
 103  * Some IPs like dsp, ipu or iva contain processors that require an HW
 104  * reset line to be asserted / deasserted in order to fully enable the
 105  * IP.  These modules may have multiple hard-reset lines that reset
 106  * different 'submodules' inside the IP block.  This function will
 107  * take the submodule out of reset and wait until the PRCM indicates
 108  * that the reset has completed before returning.  Returns 0 upon success or
 109  * -EINVAL upon an argument error, -EEXIST if the submodule was already out
 110  * of reset, or -EBUSY if the submodule did not exit reset promptly.
 111  */
 112 int am33xx_prm_deassert_hardreset(u8 shift, u8 st_shift, s16 inst,
 113                 u16 rstctrl_offs, u16 rstst_offs)
 114 {
 115         int c;
 116         u32 mask = 1 << st_shift;
 117
 118         /* Check the current status to avoid  de-asserting the line twice */
 119         if (am33xx_prm_is_hardreset_asserted(shift, inst, rstctrl_offs) == 0)
 120                 return -EEXIST;
 121
 122         /* Clear the reset status by writing 1 to the status bit */
 123         am33xx_prm_rmw_reg_bits(0xffffffff, mask, inst, rstst_offs);
 124
 125         /* de-assert the reset control line */
 126         mask = 1 << shift;
 127
 128         am33xx_prm_rmw_reg_bits(mask, 0, inst, rstctrl_offs);
 129
 130         /* wait the status to be set */
 131         omap_test_timeout(am33xx_prm_is_hardreset_asserted(st_shift, inst,
 132                                                            rstst_offs),
 133                           MAX_MODULE_HARDRESET_WAIT, c);
 134
 135         return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
 136 }
 137
 138 static int am33xx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
 139 {
 140         am33xx_prm_rmw_reg_bits(OMAP_POWERSTATE_MASK,
 141                                 (pwrst << OMAP_POWERSTATE_SHIFT),
 142                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 143         return 0;
 144 }
 145
 146 static int am33xx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
 147 {
 148         u32 v;
 149
 150         v = am33xx_prm_read_reg(pwrdm->prcm_offs,  pwrdm->pwrstctrl_offs);
 151         v &= OMAP_POWERSTATE_MASK;
 152         v >>= OMAP_POWERSTATE_SHIFT;
 153
 154         return v;
 155 }
 156
 157 static int am33xx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
 158 {
 159         u32 v;
 160
 161         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 162         v &= OMAP_POWERSTATEST_MASK;
 163         v >>= OMAP_POWERSTATEST_SHIFT;
 164
 165         return v;
 166 }
 167
 168 static int am33xx_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
 169 {
 170         u32 v;
 171
 172         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 173         v &= AM33XX_LASTPOWERSTATEENTERED_MASK;
 174         v >>= AM33XX_LASTPOWERSTATEENTERED_SHIFT;
 175
 176         return v;
 177 }
 178
 179 static int am33xx_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
 180 {
 181         am33xx_prm_rmw_reg_bits(AM33XX_LOWPOWERSTATECHANGE_MASK,
 182                                 (1 << AM33XX_LOWPOWERSTATECHANGE_SHIFT),
 183                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 184         return 0;
 185 }
 186
 187 static int am33xx_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
 188 {
 189         am33xx_prm_rmw_reg_bits(AM33XX_LASTPOWERSTATEENTERED_MASK,
 190                                 AM33XX_LASTPOWERSTATEENTERED_MASK,
 191                                 pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 192         return 0;
 193 }
 194
 195 static int am33xx_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
 196 {
 197         u32 m;
 198
 199         m = pwrdm->logicretstate_mask;
 200         if (!m)
 201                 return -EINVAL;
 202
 203         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 204                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 205
 206         return 0;
 207 }
 208
 209 static int am33xx_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
 210 {
 211         u32 v;
 212
 213         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 214         v &= AM33XX_LOGICSTATEST_MASK;
 215         v >>= AM33XX_LOGICSTATEST_SHIFT;
 216
 217         return v;
 218 }
 219
 220 static int am33xx_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
 221 {
 222         u32 v, m;
 223
 224         m = pwrdm->logicretstate_mask;
 225         if (!m)
 226                 return -EINVAL;
 227
 228         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 229         v &= m;
 230         v >>= __ffs(m);
 231
 232         return v;
 233 }
 234
 235 static int am33xx_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
 236                 u8 pwrst)
 237 {
 238         u32 m;
 239
 240         m = pwrdm->mem_on_mask[bank];
 241         if (!m)
 242                 return -EINVAL;
 243
 244         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 245                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 246
 247         return 0;
 248 }
 249
 250 static int am33xx_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
 251                                         u8 pwrst)
 252 {
 253         u32 m;
 254
 255         m = pwrdm->mem_ret_mask[bank];
 256         if (!m)
 257                 return -EINVAL;
 258
 259         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 260                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 261
 262         return 0;
 263 }
 264
 265 static int am33xx_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
 266 {
 267         u32 m, v;
 268
 269         m = pwrdm->mem_pwrst_mask[bank];
 270         if (!m)
 271                 return -EINVAL;
 272
 273         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 274         v &= m;
 275         v >>= __ffs(m);
 276
 277         return v;
 278 }
 279
 280 static int am33xx_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
 281 {
 282         u32 m, v;
 283
 284         m = pwrdm->mem_retst_mask[bank];
 285         if (!m)
 286                 return -EINVAL;
 287
 288         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 289         v &= m;
 290         v >>= __ffs(m);
 291
 292         return v;
 293 }
 294
 295 static int am33xx_pwrdm_wait_transition(struct powerdomain *pwrdm)
 296 {
 297         u32 c = 0;
 298
 299         /*
 300          * REVISIT: pwrdm_wait_transition() may be better implemented
 301          * via a callback and a periodic timer check -- how long do we expect
 302          * powerdomain transitions to take?
 303          */
 304
 305         /* XXX Is this udelay() value meaningful? */
 306         while ((am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs)
 307                         & OMAP_INTRANSITION_MASK) &&
 308                         (c++ < PWRDM_TRANSITION_BAILOUT))
 309                 udelay(1);
 310
 311         if (c > PWRDM_TRANSITION_BAILOUT) {
 312                 pr_err("powerdomain: %s: waited too long to complete transition\n",
 313                        pwrdm->name);
 314                 return -EAGAIN;
 315         }
 316
 317         pr_debug("powerdomain: completed transition in %d loops\n", c);
 318
 319         return 0;
 320 }
 321
 322 static int am33xx_check_vcvp(void)
 323 {
 324         /* No VC/VP on am33xx devices */
 325         return 0;
 326 }
 327
 328 struct pwrdm_ops am33xx_pwrdm_operations = {
 329         .pwrdm_set_next_pwrst           = am33xx_pwrdm_set_next_pwrst,
 330         .pwrdm_read_next_pwrst          = am33xx_pwrdm_read_next_pwrst,
 331         .pwrdm_read_pwrst               = am33xx_pwrdm_read_pwrst,
 332         .pwrdm_read_prev_pwrst          = am33xx_pwrdm_read_prev_pwrst,
 333         .pwrdm_set_logic_retst          = am33xx_pwrdm_set_logic_retst,
 334         .pwrdm_read_logic_pwrst         = am33xx_pwrdm_read_logic_pwrst,
 335         .pwrdm_read_logic_retst         = am33xx_pwrdm_read_logic_retst,
 336         .pwrdm_clear_all_prev_pwrst     = am33xx_pwrdm_clear_all_prev_pwrst,
 337         .pwrdm_set_lowpwrstchange       = am33xx_pwrdm_set_lowpwrstchange,
 338         .pwrdm_read_mem_pwrst           = am33xx_pwrdm_read_mem_pwrst,
 339         .pwrdm_read_mem_retst           = am33xx_pwrdm_read_mem_retst,
 340         .pwrdm_set_mem_onst             = am33xx_pwrdm_set_mem_onst,
 341         .pwrdm_set_mem_retst            = am33xx_pwrdm_set_mem_retst,
 342         .pwrdm_wait_transition          = am33xx_pwrdm_wait_transition,
 343         .pwrdm_has_voltdm               = am33xx_check_vcvp,
 344 };