kernel/arch/arm/mach-omap2/prm2xxx.c

   1 /*
   2  * OMAP2xxx PRM module functions
   3  *
   4  * Copyright (C) 2010-2012 Texas Instruments, Inc.
   5  * Copyright (C) 2010 Nokia Corporation
   6  * Benoît Cousson
   7  * Paul Walmsley
   8  * Rajendra Nayak <rnayak@ti.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/io.h>
  19 #include <linux/irq.h>
  20
  21 #include "powerdomain.h"
  22 #include "clockdomain.h"
  23 #include "prm2xxx.h"
  24 #include "cm2xxx_3xxx.h"
  25 #include "prm-regbits-24xx.h"
  26
  27 /*
  28  * OMAP24xx PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED bits -
  29  * these are reversed from the bits used on OMAP3+
  30  */
  31 #define OMAP24XX_PWRDM_POWER_ON                 0x0
  32 #define OMAP24XX_PWRDM_POWER_RET                0x1
  33 #define OMAP24XX_PWRDM_POWER_OFF                0x3
  34
  35 /*
  36  * omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
  37  *   hardware register (which are specific to the OMAP2xxx SoCs) to
  38  *   reset source ID bit shifts (which is an OMAP SoC-independent
  39  *   enumeration)
  40  */
  41 static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
  42         { OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
  43         { OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
  44         { OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
  45         { OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
  46         { OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
  47         { OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
  48         { -1, -1 },
  49 };
  50
  51 /**
  52  * omap2xxx_prm_read_reset_sources - return the last SoC reset source
  53  *
  54  * Return a u32 representing the last reset sources of the SoC.  The
  55  * returned reset source bits are standardized across OMAP SoCs.
  56  */
  57 static u32 omap2xxx_prm_read_reset_sources(void)
  58 {
  59         struct prm_reset_src_map *p;
  60         u32 r = 0;
  61         u32 v;
  62
  63         v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
  64
  65         p = omap2xxx_prm_reset_src_map;
  66         while (p->reg_shift >= 0 && p->std_shift >= 0) {
  67                 if (v & (1 << p->reg_shift))
  68                         r |= 1 << p->std_shift;
  69                 p++;
  70         }
  71
  72         return r;
  73 }
  74
  75 /**
  76  * omap2xxx_pwrst_to_common_pwrst - convert OMAP2xxx pwrst to common pwrst
  77  * @omap2xxx_pwrst: OMAP2xxx hardware power state to convert
  78  *
  79  * Return the common power state bits corresponding to the OMAP2xxx
  80  * hardware power state bits @omap2xxx_pwrst, or -EINVAL upon error.
  81  */
  82 static int omap2xxx_pwrst_to_common_pwrst(u8 omap2xxx_pwrst)
  83 {
  84         u8 pwrst;
  85
  86         switch (omap2xxx_pwrst) {
  87         case OMAP24XX_PWRDM_POWER_OFF:
  88                 pwrst = PWRDM_POWER_OFF;
  89                 break;
  90         case OMAP24XX_PWRDM_POWER_RET:
  91                 pwrst = PWRDM_POWER_RET;
  92                 break;
  93         case OMAP24XX_PWRDM_POWER_ON:
  94                 pwrst = PWRDM_POWER_ON;
  95                 break;
  96         default:
  97                 return -EINVAL;
  98         }
  99
 100         return pwrst;
 101 }
 102
 103 /**
 104  * omap2xxx_prm_dpll_reset - use DPLL reset to reboot the OMAP SoC
 105  *
 106  * Set the DPLL reset bit, which should reboot the SoC.  This is the
 107  * recommended way to restart the SoC.  No return value.
 108  */
 109 static void omap2xxx_prm_dpll_reset(void)
 110 {
 111         omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, WKUP_MOD,
 112                                    OMAP2_RM_RSTCTRL);
 113         /* OCP barrier */
 114         omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTCTRL);
 115 }
 116
 117 /**
 118  * omap2xxx_prm_clear_mod_irqs - clear wakeup status bits for a module
 119  * @module: PRM module to clear wakeups from
 120  * @regs: register offset to clear
 121  * @wkst_mask: wakeup status mask to clear
 122  *
 123  * Clears wakeup status bits for a given module, so that the device can
 124  * re-enter idle.
 125  */
 126 static int omap2xxx_prm_clear_mod_irqs(s16 module, u8 regs, u32 wkst_mask)
 127 {
 128         u32 wkst;
 129
 130         wkst = omap2_prm_read_mod_reg(module, regs);
 131         wkst &= wkst_mask;
 132         omap2_prm_write_mod_reg(wkst, module, regs);
 133         return 0;
 134 }
 135
 136 int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
 137 {
 138         omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
 139                                    clkdm->pwrdm.ptr->prcm_offs,
 140                                    OMAP2_PM_PWSTCTRL);
 141         return 0;
 142 }
 143
 144 int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
 145 {
 146         omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
 147                                      clkdm->pwrdm.ptr->prcm_offs,
 148                                      OMAP2_PM_PWSTCTRL);
 149         return 0;
 150 }
 151
 152 static int omap2xxx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
 153 {
 154         u8 omap24xx_pwrst;
 155
 156         switch (pwrst) {
 157         case PWRDM_POWER_OFF:
 158                 omap24xx_pwrst = OMAP24XX_PWRDM_POWER_OFF;
 159                 break;
 160         case PWRDM_POWER_RET:
 161                 omap24xx_pwrst = OMAP24XX_PWRDM_POWER_RET;
 162                 break;
 163         case PWRDM_POWER_ON:
 164                 omap24xx_pwrst = OMAP24XX_PWRDM_POWER_ON;
 165                 break;
 166         default:
 167                 return -EINVAL;
 168         }
 169
 170         omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
 171                                    (omap24xx_pwrst << OMAP_POWERSTATE_SHIFT),
 172                                    pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
 173         return 0;
 174 }
 175
 176 static int omap2xxx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
 177 {
 178         u8 omap2xxx_pwrst;
 179
 180         omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
 181                                                        OMAP2_PM_PWSTCTRL,
 182                                                        OMAP_POWERSTATE_MASK);
 183
 184         return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
 185 }
 186
 187 static int omap2xxx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
 188 {
 189         u8 omap2xxx_pwrst;
 190
 191         omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
 192                                                        OMAP2_PM_PWSTST,
 193                                                        OMAP_POWERSTATEST_MASK);
 194
 195         return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
 196 }
 197
 198 struct pwrdm_ops omap2_pwrdm_operations = {
 199         .pwrdm_set_next_pwrst   = omap2xxx_pwrdm_set_next_pwrst,
 200         .pwrdm_read_next_pwrst  = omap2xxx_pwrdm_read_next_pwrst,
 201         .pwrdm_read_pwrst       = omap2xxx_pwrdm_read_pwrst,
 202         .pwrdm_set_logic_retst  = omap2_pwrdm_set_logic_retst,
 203         .pwrdm_set_mem_onst     = omap2_pwrdm_set_mem_onst,
 204         .pwrdm_set_mem_retst    = omap2_pwrdm_set_mem_retst,
 205         .pwrdm_read_mem_pwrst   = omap2_pwrdm_read_mem_pwrst,
 206         .pwrdm_read_mem_retst   = omap2_pwrdm_read_mem_retst,
 207         .pwrdm_wait_transition  = omap2_pwrdm_wait_transition,
 208 };
 209
 210 /*
 211  *
 212  */
 213
 214 static struct prm_ll_data omap2xxx_prm_ll_data = {
 215         .read_reset_sources = &omap2xxx_prm_read_reset_sources,
 216         .assert_hardreset = &omap2_prm_assert_hardreset,
 217         .deassert_hardreset = &omap2_prm_deassert_hardreset,
 218         .is_hardreset_asserted = &omap2_prm_is_hardreset_asserted,
 219         .reset_system = &omap2xxx_prm_dpll_reset,
 220         .clear_mod_irqs = &omap2xxx_prm_clear_mod_irqs,
 221 };
 222
 223 int __init omap2xxx_prm_init(const struct omap_prcm_init_data *data)
 224 {
 225         return prm_register(&omap2xxx_prm_ll_data);
 226 }
 227
 228 static void __exit omap2xxx_prm_exit(void)
 229 {
 230         prm_unregister(&omap2xxx_prm_ll_data);
 231 }
 232 __exitcall(omap2xxx_prm_exit);