/*
   * OMAP2xxx PRM module functions
   *
   * Copyright (C) 2010-2012 Texas Instruments, Inc.
   * Copyright (C) 2010 Nokia Corporation
   * Benoît Cousson
   * Paul Walmsley
   * Rajendra Nayak <rnayak@ti.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/err.h>
  #include <linux/io.h>
  #include <linux/irq.h>
  
  #include "soc.h"
  #include "common.h"
  #include "vp.h"
  #include "powerdomain.h"
  #include "clockdomain.h"
  #include "prm2xxx.h"
  #include "cm2xxx_3xxx.h"
  #include "prm-regbits-24xx.h"
  
  /*
   * OMAP24xx PM_PWSTCTRL_*.POWERSTATE and PM_PWSTST_*.LASTSTATEENTERED bits -
   * these are reversed from the bits used on OMAP3+
   */
  #define OMAP24XX_PWRDM_POWER_ON			0x0
  #define OMAP24XX_PWRDM_POWER_RET		0x1
  #define OMAP24XX_PWRDM_POWER_OFF		0x3
  
  /*
   * omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
   *   hardware register (which are specific to the OMAP2xxx SoCs) to
   *   reset source ID bit shifts (which is an OMAP SoC-independent
   *   enumeration)
   */
  static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
  	{ OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
  	{ OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
  	{ OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
  	{ OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
  	{ OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
  	{ OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
  	{ -1, -1 },
  };
  
  /**
   * omap2xxx_prm_read_reset_sources - return the last SoC reset source
   *
   * Return a u32 representing the last reset sources of the SoC.  The
   * returned reset source bits are standardized across OMAP SoCs.
   */
  static u32 omap2xxx_prm_read_reset_sources(void)
  {
  	struct prm_reset_src_map *p;
  	u32 r = 0;
  	u32 v;
  
  	v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
  
  	p = omap2xxx_prm_reset_src_map;
  	while (p->reg_shift >= 0 && p->std_shift >= 0) {
  		if (v & (1 << p->reg_shift))
  			r |= 1 << p->std_shift;
  		p++;
  	}
  
  	return r;
  }
  
  /**
   * omap2xxx_pwrst_to_common_pwrst - convert OMAP2xxx pwrst to common pwrst
   * @omap2xxx_pwrst: OMAP2xxx hardware power state to convert
   *
   * Return the common power state bits corresponding to the OMAP2xxx
   * hardware power state bits @omap2xxx_pwrst, or -EINVAL upon error.
   */
  static int omap2xxx_pwrst_to_common_pwrst(u8 omap2xxx_pwrst)
  {
  	u8 pwrst;
  
  	switch (omap2xxx_pwrst) {
  	case OMAP24XX_PWRDM_POWER_OFF:
  		pwrst = PWRDM_POWER_OFF;
  		break;
  	case OMAP24XX_PWRDM_POWER_RET:
  		pwrst = PWRDM_POWER_RET;
  		break;
  	case OMAP24XX_PWRDM_POWER_ON:
  		pwrst = PWRDM_POWER_ON;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	return pwrst;
  }
  
  /**
   * omap2xxx_prm_dpll_reset - use DPLL reset to reboot the OMAP SoC
   *
   * Set the DPLL reset bit, which should reboot the SoC.  This is the
   * recommended way to restart the SoC.  No return value.
   */
  void omap2xxx_prm_dpll_reset(void)
  {
  	omap2_prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, WKUP_MOD,
  				   OMAP2_RM_RSTCTRL);
  	/* OCP barrier */
  	omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTCTRL);
  }
  
  int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
  {
  	omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
  				   clkdm->pwrdm.ptr->prcm_offs,
  				   OMAP2_PM_PWSTCTRL);
  	return 0;
  }
  
  int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
  {
  	omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
  				     clkdm->pwrdm.ptr->prcm_offs,
  				     OMAP2_PM_PWSTCTRL);
  	return 0;
  }
  
  static int omap2xxx_pwrdm_set_next_pwrst(struct powerdomain *pwrdm, u8 pwrst)
  {
  	u8 omap24xx_pwrst;
  
  	switch (pwrst) {
  	case PWRDM_POWER_OFF:
  		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_OFF;
  		break;
  	case PWRDM_POWER_RET:
  		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_RET;
  		break;
  	case PWRDM_POWER_ON:
  		omap24xx_pwrst = OMAP24XX_PWRDM_POWER_ON;
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	omap2_prm_rmw_mod_reg_bits(OMAP_POWERSTATE_MASK,
  				   (omap24xx_pwrst << OMAP_POWERSTATE_SHIFT),
  				   pwrdm->prcm_offs, OMAP2_PM_PWSTCTRL);
  	return 0;
  }
  
  static int omap2xxx_pwrdm_read_next_pwrst(struct powerdomain *pwrdm)
  {
  	u8 omap2xxx_pwrst;
  
  	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
  						       OMAP2_PM_PWSTCTRL,
  						       OMAP_POWERSTATE_MASK);
  
  	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
  }
  
  static int omap2xxx_pwrdm_read_pwrst(struct powerdomain *pwrdm)
  {
  	u8 omap2xxx_pwrst;
  
  	omap2xxx_pwrst = omap2_prm_read_mod_bits_shift(pwrdm->prcm_offs,
  						       OMAP2_PM_PWSTST,
  						       OMAP_POWERSTATEST_MASK);
  
  	return omap2xxx_pwrst_to_common_pwrst(omap2xxx_pwrst);
  }
  
  struct pwrdm_ops omap2_pwrdm_operations = {
  	.pwrdm_set_next_pwrst	= omap2xxx_pwrdm_set_next_pwrst,
  	.pwrdm_read_next_pwrst	= omap2xxx_pwrdm_read_next_pwrst,
  	.pwrdm_read_pwrst	= omap2xxx_pwrdm_read_pwrst,
  	.pwrdm_set_logic_retst	= omap2_pwrdm_set_logic_retst,
  	.pwrdm_set_mem_onst	= omap2_pwrdm_set_mem_onst,
  	.pwrdm_set_mem_retst	= omap2_pwrdm_set_mem_retst,
  	.pwrdm_read_mem_pwrst	= omap2_pwrdm_read_mem_pwrst,
  	.pwrdm_read_mem_retst	= omap2_pwrdm_read_mem_retst,
  	.pwrdm_wait_transition	= omap2_pwrdm_wait_transition,
  };
  
  /*
   *
   */
  
  static struct prm_ll_data omap2xxx_prm_ll_data = {
  	.read_reset_sources = &omap2xxx_prm_read_reset_sources,
  };
  
  int __init omap2xxx_prm_init(void)
  {
  	if (!cpu_is_omap24xx())
  		return 0;
  
  	return prm_register(&omap2xxx_prm_ll_data);
  }
  
  static void __exit omap2xxx_prm_exit(void)
  {
  	if (!cpu_is_omap24xx())
  		return;
  
  	/* Should never happen */
  	WARN(prm_unregister(&omap2xxx_prm_ll_data),
  	     "%s: prm_ll_data function pointer mismatch
  ", __func__);
  }
  __exitcall(omap2xxx_prm_exit);