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 #define AM33XX_PRM_RSTCTRL_OFFSET               0x0000
  27
  28 #define AM33XX_RST_GLOBAL_WARM_SW_MASK          (1 << 0)
  29
  30 /* Read a register in a PRM instance */
  31 static u32 am33xx_prm_read_reg(s16 inst, u16 idx)
  32 {
  33         return readl_relaxed(prm_base.va + inst + idx);
  34 }
  35
  36 /* Write into a register in a PRM instance */
  37 static void am33xx_prm_write_reg(u32 val, s16 inst, u16 idx)
  38 {
  39         writel_relaxed(val, prm_base.va + inst + idx);
  40 }
  41
  42 /* Read-modify-write a register in PRM. Caller must lock */
  43 static u32 am33xx_prm_rmw_reg_bits(u32 mask, u32 bits, s16 inst, s16 idx)
  44 {
  45         u32 v;
  46
  47         v = am33xx_prm_read_reg(inst, idx);
  48         v &= ~mask;
  49         v |= bits;
  50         am33xx_prm_write_reg(v, inst, idx);
  51
  52         return v;
  53 }
  54
  55 /**
  56  * am33xx_prm_is_hardreset_asserted - read the HW reset line state of
  57  * submodules contained in the hwmod module
  58  * @shift: register bit shift corresponding to the reset line to check
  59  * @part: PRM partition, ignored for AM33xx
  60  * @inst: CM instance register offset (*_INST macro)
  61  * @rstctrl_offs: RM_RSTCTRL register address offset for this module
  62  *
  63  * Returns 1 if the (sub)module hardreset line is currently asserted,
  64  * 0 if the (sub)module hardreset line is not currently asserted, or
  65  * -EINVAL upon parameter error.
  66  */
  67 static int am33xx_prm_is_hardreset_asserted(u8 shift, u8 part, s16 inst,
  68                                             u16 rstctrl_offs)
  69 {
  70         u32 v;
  71
  72         v = am33xx_prm_read_reg(inst, rstctrl_offs);
  73         v &= 1 << shift;
  74         v >>= shift;
  75
  76         return v;
  77 }
  78
  79 /**
  80  * am33xx_prm_assert_hardreset - assert the HW reset line of a submodule
  81  * @shift: register bit shift corresponding to the reset line to assert
  82  * @part: CM partition, ignored for AM33xx
  83  * @inst: CM instance register offset (*_INST macro)
  84  * @rstctrl_reg: RM_RSTCTRL register address for this module
  85  *
  86  * Some IPs like dsp, ipu or iva contain processors that require an HW
  87  * reset line to be asserted / deasserted in order to fully enable the
  88  * IP.  These modules may have multiple hard-reset lines that reset
  89  * different 'submodules' inside the IP block.  This function will
  90  * place the submodule into reset.  Returns 0 upon success or -EINVAL
  91  * upon an argument error.
  92  */
  93 static int am33xx_prm_assert_hardreset(u8 shift, u8 part, s16 inst,
  94                                        u16 rstctrl_offs)
  95 {
  96         u32 mask = 1 << shift;
  97
  98         am33xx_prm_rmw_reg_bits(mask, mask, inst, rstctrl_offs);
  99
 100         return 0;
 101 }
 102
 103 /**
 104  * am33xx_prm_deassert_hardreset - deassert a submodule hardreset line and
 105  * wait
 106  * @shift: register bit shift corresponding to the reset line to deassert
 107  * @st_shift: reset status register bit shift corresponding to the reset line
 108  * @part: PRM partition, not used for AM33xx
 109  * @inst: CM instance register offset (*_INST macro)
 110  * @rstctrl_reg: RM_RSTCTRL register address for this module
 111  * @rstst_reg: RM_RSTST register address for this module
 112  *
 113  * Some IPs like dsp, ipu or iva contain processors that require an HW
 114  * reset line to be asserted / deasserted in order to fully enable the
 115  * IP.  These modules may have multiple hard-reset lines that reset
 116  * different 'submodules' inside the IP block.  This function will
 117  * take the submodule out of reset and wait until the PRCM indicates
 118  * that the reset has completed before returning.  Returns 0 upon success or
 119  * -EINVAL upon an argument error, -EEXIST if the submodule was already out
 120  * of reset, or -EBUSY if the submodule did not exit reset promptly.
 121  */
 122 static int am33xx_prm_deassert_hardreset(u8 shift, u8 st_shift, u8 part,
 123                                          s16 inst, u16 rstctrl_offs,
 124                                          u16 rstst_offs)
 125 {
 126         int c;
 127         u32 mask = 1 << st_shift;
 128
 129         /* Check the current status to avoid  de-asserting the line twice */
 130         if (am33xx_prm_is_hardreset_asserted(shift, 0, inst, rstctrl_offs) == 0)
 131                 return -EEXIST;
 132
 133         /* Clear the reset status by writing 1 to the status bit */
 134         am33xx_prm_rmw_reg_bits(0xffffffff, mask, inst, rstst_offs);
 135
 136         /* de-assert the reset control line */
 137         mask = 1 << shift;
 138
 139         am33xx_prm_rmw_reg_bits(mask, 0, inst, rstctrl_offs);
 140
 141         /* wait the status to be set */
 142         omap_test_timeout(am33xx_prm_is_hardreset_asserted(st_shift, 0, inst,
 143                                                            rstst_offs),
 144                           MAX_MODULE_HARDRESET_WAIT, c);
 145
 146         return (c == MAX_MODULE_HARDRESET_WAIT) ? -EBUSY : 0;
 147 }
 148
 149 static int am33xx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
 150 {
 151         am33xx_prm_rmw_reg_bits(OMAP_POWERSTATE_MASK,
 152                                 (pwrst << OMAP_POWERSTATE_SHIFT),
 153                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 154         return 0;
 155 }
 156
 157 static int am33xx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
 158 {
 159         u32 v;
 160
 161         v = am33xx_prm_read_reg(pwrdm->prcm_offs,  pwrdm->pwrstctrl_offs);
 162         v &= OMAP_POWERSTATE_MASK;
 163         v >>= OMAP_POWERSTATE_SHIFT;
 164
 165         return v;
 166 }
 167
 168 static int am33xx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
 169 {
 170         u32 v;
 171
 172         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 173         v &= OMAP_POWERSTATEST_MASK;
 174         v >>= OMAP_POWERSTATEST_SHIFT;
 175
 176         return v;
 177 }
 178
 179 static int am33xx_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
 180 {
 181         u32 v;
 182
 183         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 184         v &= AM33XX_LASTPOWERSTATEENTERED_MASK;
 185         v >>= AM33XX_LASTPOWERSTATEENTERED_SHIFT;
 186
 187         return v;
 188 }
 189
 190 static int am33xx_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
 191 {
 192         am33xx_prm_rmw_reg_bits(AM33XX_LOWPOWERSTATECHANGE_MASK,
 193                                 (1 << AM33XX_LOWPOWERSTATECHANGE_SHIFT),
 194                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 195         return 0;
 196 }
 197
 198 static int am33xx_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
 199 {
 200         am33xx_prm_rmw_reg_bits(AM33XX_LASTPOWERSTATEENTERED_MASK,
 201                                 AM33XX_LASTPOWERSTATEENTERED_MASK,
 202                                 pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 203         return 0;
 204 }
 205
 206 static int am33xx_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
 207 {
 208         u32 m;
 209
 210         m = pwrdm->logicretstate_mask;
 211         if (!m)
 212                 return -EINVAL;
 213
 214         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 215                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 216
 217         return 0;
 218 }
 219
 220 static int am33xx_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
 221 {
 222         u32 v;
 223
 224         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 225         v &= AM33XX_LOGICSTATEST_MASK;
 226         v >>= AM33XX_LOGICSTATEST_SHIFT;
 227
 228         return v;
 229 }
 230
 231 static int am33xx_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
 232 {
 233         u32 v, m;
 234
 235         m = pwrdm->logicretstate_mask;
 236         if (!m)
 237                 return -EINVAL;
 238
 239         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 240         v &= m;
 241         v >>= __ffs(m);
 242
 243         return v;
 244 }
 245
 246 static int am33xx_pwrdm_set_mem_onst(struct powerdomain *pwrdm, u8 bank,
 247                 u8 pwrst)
 248 {
 249         u32 m;
 250
 251         m = pwrdm->mem_on_mask[bank];
 252         if (!m)
 253                 return -EINVAL;
 254
 255         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 256                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 257
 258         return 0;
 259 }
 260
 261 static int am33xx_pwrdm_set_mem_retst(struct powerdomain *pwrdm, u8 bank,
 262                                         u8 pwrst)
 263 {
 264         u32 m;
 265
 266         m = pwrdm->mem_ret_mask[bank];
 267         if (!m)
 268                 return -EINVAL;
 269
 270         am33xx_prm_rmw_reg_bits(m, (pwrst << __ffs(m)),
 271                                 pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 272
 273         return 0;
 274 }
 275
 276 static int am33xx_pwrdm_read_mem_pwrst(struct powerdomain *pwrdm, u8 bank)
 277 {
 278         u32 m, v;
 279
 280         m = pwrdm->mem_pwrst_mask[bank];
 281         if (!m)
 282                 return -EINVAL;
 283
 284         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs);
 285         v &= m;
 286         v >>= __ffs(m);
 287
 288         return v;
 289 }
 290
 291 static int am33xx_pwrdm_read_mem_retst(struct powerdomain *pwrdm, u8 bank)
 292 {
 293         u32 m, v;
 294
 295         m = pwrdm->mem_retst_mask[bank];
 296         if (!m)
 297                 return -EINVAL;
 298
 299         v = am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstctrl_offs);
 300         v &= m;
 301         v >>= __ffs(m);
 302
 303         return v;
 304 }
 305
 306 static int am33xx_pwrdm_wait_transition(struct powerdomain *pwrdm)
 307 {
 308         u32 c = 0;
 309
 310         /*
 311          * REVISIT: pwrdm_wait_transition() may be better implemented
 312          * via a callback and a periodic timer check -- how long do we expect
 313          * powerdomain transitions to take?
 314          */
 315
 316         /* XXX Is this udelay() value meaningful? */
 317         while ((am33xx_prm_read_reg(pwrdm->prcm_offs, pwrdm->pwrstst_offs)
 318                         & OMAP_INTRANSITION_MASK) &&
 319                         (c++ < PWRDM_TRANSITION_BAILOUT))
 320                 udelay(1);
 321
 322         if (c > PWRDM_TRANSITION_BAILOUT) {
 323                 pr_err("powerdomain: %s: waited too long to complete transition\n",
 324                        pwrdm->name);
 325                 return -EAGAIN;
 326         }
 327
 328         pr_debug("powerdomain: completed transition in %d loops\n", c);
 329
 330         return 0;
 331 }
 332
 333 static int am33xx_check_vcvp(void)
 334 {
 335         /* No VC/VP on am33xx devices */
 336         return 0;
 337 }
 338
 339 /**
 340  * am33xx_prm_global_warm_sw_reset - reboot the device via warm reset
 341  *
 342  * Immediately reboots the device through warm reset.
 343  */
 344 static void am33xx_prm_global_warm_sw_reset(void)
 345 {
 346         am33xx_prm_rmw_reg_bits(AM33XX_RST_GLOBAL_WARM_SW_MASK,
 347                                 AM33XX_RST_GLOBAL_WARM_SW_MASK,
 348                                 AM33XX_PRM_DEVICE_MOD,
 349                                 AM33XX_PRM_RSTCTRL_OFFSET);
 350
 351         /* OCP barrier */
 352         (void)am33xx_prm_read_reg(AM33XX_PRM_DEVICE_MOD,
 353                                   AM33XX_PRM_RSTCTRL_OFFSET);
 354 }
 355
 356 struct pwrdm_ops am33xx_pwrdm_operations = {
 357         .pwrdm_set_next_pwrst           = am33xx_pwrdm_set_next_pwrst,
 358         .pwrdm_read_next_pwrst          = am33xx_pwrdm_read_next_pwrst,
 359         .pwrdm_read_pwrst               = am33xx_pwrdm_read_pwrst,
 360         .pwrdm_read_prev_pwrst          = am33xx_pwrdm_read_prev_pwrst,
 361         .pwrdm_set_logic_retst          = am33xx_pwrdm_set_logic_retst,
 362         .pwrdm_read_logic_pwrst         = am33xx_pwrdm_read_logic_pwrst,
 363         .pwrdm_read_logic_retst         = am33xx_pwrdm_read_logic_retst,
 364         .pwrdm_clear_all_prev_pwrst     = am33xx_pwrdm_clear_all_prev_pwrst,
 365         .pwrdm_set_lowpwrstchange       = am33xx_pwrdm_set_lowpwrstchange,
 366         .pwrdm_read_mem_pwrst           = am33xx_pwrdm_read_mem_pwrst,
 367         .pwrdm_read_mem_retst           = am33xx_pwrdm_read_mem_retst,
 368         .pwrdm_set_mem_onst             = am33xx_pwrdm_set_mem_onst,
 369         .pwrdm_set_mem_retst            = am33xx_pwrdm_set_mem_retst,
 370         .pwrdm_wait_transition          = am33xx_pwrdm_wait_transition,
 371         .pwrdm_has_voltdm               = am33xx_check_vcvp,
 372 };
 373
 374 static struct prm_ll_data am33xx_prm_ll_data = {
 375         .assert_hardreset               = am33xx_prm_assert_hardreset,
 376         .deassert_hardreset             = am33xx_prm_deassert_hardreset,
 377         .is_hardreset_asserted          = am33xx_prm_is_hardreset_asserted,
 378         .reset_system                   = am33xx_prm_global_warm_sw_reset,
 379 };
 380
 381 int __init am33xx_prm_init(const struct omap_prcm_init_data *data)
 382 {
 383         return prm_register(&am33xx_prm_ll_data);
 384 }
 385
 386 static void __exit am33xx_prm_exit(void)
 387 {
 388         prm_unregister(&am33xx_prm_ll_data);
 389 }
 390 __exitcall(am33xx_prm_exit);