arch/arm/mach-omap2/powerdomain33xx.c

   1 /*
   2  * AM33XX Powerdomain control
   3  *
   4  * Copyright (C) 2011 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/io.h>
  17 #include <linux/errno.h>
  18 #include <linux/delay.h>
  19
  20 #include <plat/prcm.h>
  21
  22 #include "powerdomain.h"
  23 #include "prm33xx.h"
  24 #include "prm-regbits-33xx.h"
  25 #include "prminst33xx.h"
  26
  27
  28 static int am33xx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
  29 {
  30         am33xx_prminst_rmw_inst_reg_bits(OMAP_POWERSTATE_MASK,
  31                                         (pwrst << OMAP_POWERSTATE_SHIFT),
  32                                         pwrdm->prcm_offs, AM33XX_PM_PWSTCTRL);
  33         return 0;
  34 }
  35
  36 static int am33xx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
  37 {
  38         u32 v;
  39
  40         v = am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTCTRL);
  41         v &= OMAP_POWERSTATE_MASK;
  42         v >>= OMAP_POWERSTATE_SHIFT;
  43
  44         return v;
  45 }
  46
  47 static int am33xx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
  48 {
  49         u32 v;
  50
  51         v = am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTST);
  52         v &= OMAP_POWERSTATEST_MASK;
  53         v >>= OMAP_POWERSTATEST_SHIFT;
  54
  55         return v;
  56 }
  57
  58 static int am33xx_pwrdm_read_prev_pwrst(struct powerdomain *pwrdm)
  59 {
  60         u32 v;
  61
  62         v = am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTST);
  63         v &= AM33XX_LASTPOWERSTATEENTERED_MASK;
  64         v >>= AM33XX_LASTPOWERSTATEENTERED_SHIFT;
  65
  66         return v;
  67 }
  68
  69 static int am33xx_pwrdm_set_lowpwrstchange(struct powerdomain *pwrdm)
  70 {
  71         am33xx_prminst_rmw_inst_reg_bits(AM33XX_LOWPOWERSTATECHANGE_MASK,
  72                         (1 << AM33XX_LOWPOWERSTATECHANGE_SHIFT),
  73                         pwrdm->prcm_offs, AM33XX_PM_PWSTCTRL);
  74         return 0;
  75 }
  76
  77 static int am33xx_pwrdm_clear_all_prev_pwrst(struct powerdomain *pwrdm)
  78 {
  79         am33xx_prminst_rmw_inst_reg_bits(AM33XX_LASTPOWERSTATEENTERED_MASK,
  80                         AM33XX_LASTPOWERSTATEENTERED_MASK,
  81                         pwrdm->prcm_offs, AM33XX_PM_PWSTST);
  82         return 0;
  83 }
  84
  85 static int am33xx_pwrdm_set_logic_retst(struct powerdomain *pwrdm, u8 pwrst)
  86 {
  87         u32 v;
  88
  89         v = pwrst << __ffs(AM33XX_LOGICRETSTATE_MASK);
  90         am33xx_prminst_rmw_inst_reg_bits(AM33XX_LOGICRETSTATE_MASK, v,
  91                         pwrdm->prcm_offs, AM33XX_PM_PWSTCTRL);
  92
  93         return 0;
  94 }
  95
  96 static int am33xx_pwrdm_read_logic_pwrst(struct powerdomain *pwrdm)
  97 {
  98         u32 v;
  99
 100         v = am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTST);
 101         v &= AM33XX_LOGICSTATEST_MASK;
 102         v >>= AM33XX_LOGICSTATEST_SHIFT;
 103
 104         return v;
 105 }
 106
 107 static int am33xx_pwrdm_read_logic_retst(struct powerdomain *pwrdm)
 108 {
 109         u32 v;
 110
 111         v = am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTCTRL);
 112         v &= AM33XX_LOGICRETSTATE_MASK;
 113         v >>= AM33XX_LOGICRETSTATE_SHIFT;
 114
 115         return v;
 116 }
 117
 118 static int am33xx_pwrdm_wait_transition(struct powerdomain *pwrdm)
 119 {
 120         u32 c = 0;
 121
 122         /*
 123          * REVISIT: pwrdm_wait_transition() may be better implemented
 124          * via a callback and a periodic timer check -- how long do we expect
 125          * powerdomain transitions to take?
 126          */
 127
 128         /* XXX Is this udelay() value meaningful? */
 129         while ((am33xx_prminst_read_inst_reg(pwrdm->prcm_offs, AM33XX_PM_PWSTST)
 130                 & OMAP_INTRANSITION_MASK) && (c++ < PWRDM_TRANSITION_BAILOUT))
 131                 udelay(1);
 132
 133         if (c > PWRDM_TRANSITION_BAILOUT) {
 134                 printk(KERN_ERR "powerdomain: waited too long for "
 135                         "powerdomain %s to complete transition\n", pwrdm->name);
 136                 return -EAGAIN;
 137         }
 138
 139         pr_debug("powerdomain: completed transition in %d loops\n", c);
 140
 141         return 0;
 142 }
 143
 144 struct pwrdm_ops am33xx_pwrdm_operations = {
 145         .pwrdm_set_next_pwrst           = am33xx_pwrdm_set_next_pwrst,
 146         .pwrdm_read_next_pwrst          = am33xx_pwrdm_read_next_pwrst,
 147         .pwrdm_read_pwrst               = am33xx_pwrdm_read_pwrst,
 148         .pwrdm_read_prev_pwrst          = am33xx_pwrdm_read_prev_pwrst,
 149         .pwrdm_set_logic_retst          = am33xx_pwrdm_set_logic_retst,
 150         .pwrdm_read_logic_pwrst         = am33xx_pwrdm_read_logic_pwrst,
 151         .pwrdm_read_logic_retst         = am33xx_pwrdm_read_logic_retst,
 152         .pwrdm_clear_all_prev_pwrst     = am33xx_pwrdm_clear_all_prev_pwrst,
 153         .pwrdm_set_lowpwrstchange       = am33xx_pwrdm_set_lowpwrstchange,
 154         .pwrdm_wait_transition          = am33xx_pwrdm_wait_transition,
 155 };