LXR linux/arch/arm/mach-davinci/psc.c

   1/*
   2 * TI DaVinci Power and Sleep Controller (PSC)
   3 *
   4 * Copyright (C) 2006 Texas Instruments.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, write to the Free Software
  18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 *
  20 */
  21#include <linux/kernel.h>
  22#include <linux/init.h>
  23#include <linux/io.h>
  24
  25#include <mach/cputype.h>
  26#include <mach/psc.h>
  27
  28#include "clock.h"
  29
  30/* Return nonzero iff the domain's clock is active */
  31int __init davinci_psc_is_clk_active(unsigned int ctlr, unsigned int id)
  32{
  33        void __iomem *psc_base;
  34        u32 mdstat;
  35        struct davinci_soc_info *soc_info = &davinci_soc_info;
  36
  37        if (!soc_info->psc_bases || (ctlr >= soc_info->psc_bases_num)) {
  38                pr_warning("PSC: Bad psc data: 0x%x[%d]\n",
  39                                (int)soc_info->psc_bases, ctlr);
  40                return 0;
  41        }
  42
  43        psc_base = ioremap(soc_info->psc_bases[ctlr], SZ_4K);
  44        mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
  45        iounmap(psc_base);
  46
  47        /* if clocked, state can be "Enable" or "SyncReset" */
  48        return mdstat & BIT(12);
  49}
  50
  51/* Enable or disable a PSC domain */
  52void davinci_psc_config(unsigned int domain, unsigned int ctlr,
  53                unsigned int id, bool enable, u32 flags)
  54{
  55        u32 epcpr, ptcmd, ptstat, pdstat, pdctl, mdstat, mdctl;
  56        void __iomem *psc_base;
  57        struct davinci_soc_info *soc_info = &davinci_soc_info;
  58        u32 next_state = PSC_STATE_ENABLE;
  59
  60        if (!soc_info->psc_bases || (ctlr >= soc_info->psc_bases_num)) {
  61                pr_warning("PSC: Bad psc data: 0x%x[%d]\n",
  62                                (int)soc_info->psc_bases, ctlr);
  63                return;
  64        }
  65
  66        psc_base = ioremap(soc_info->psc_bases[ctlr], SZ_4K);
  67
  68        if (!enable) {
  69                if (flags & PSC_SWRSTDISABLE)
  70                        next_state = PSC_STATE_SWRSTDISABLE;
  71                else
  72                        next_state = PSC_STATE_DISABLE;
  73        }
  74
  75        mdctl = __raw_readl(psc_base + MDCTL + 4 * id);
  76        mdctl &= ~MDSTAT_STATE_MASK;
  77        mdctl |= next_state;
  78        if (flags & PSC_FORCE)
  79                mdctl |= MDCTL_FORCE;
  80        __raw_writel(mdctl, psc_base + MDCTL + 4 * id);
  81
  82        pdstat = __raw_readl(psc_base + PDSTAT + 4 * domain);
  83        if ((pdstat & PDSTAT_STATE_MASK) == 0) {
  84                pdctl = __raw_readl(psc_base + PDCTL + 4 * domain);
  85                pdctl |= PDCTL_NEXT;
  86                __raw_writel(pdctl, psc_base + PDCTL + 4 * domain);
  87
  88                ptcmd = 1 << domain;
  89                __raw_writel(ptcmd, psc_base + PTCMD);
  90
  91                do {
  92                        epcpr = __raw_readl(psc_base + EPCPR);
  93                } while ((((epcpr >> domain) & 1) == 0));
  94
  95                pdctl = __raw_readl(psc_base + PDCTL + 4 * domain);
  96                pdctl |= PDCTL_EPCGOOD;
  97                __raw_writel(pdctl, psc_base + PDCTL + 4 * domain);
  98        } else {
  99                ptcmd = 1 << domain;
 100                __raw_writel(ptcmd, psc_base + PTCMD);
 101        }
 102
 103        do {
 104                ptstat = __raw_readl(psc_base + PTSTAT);
 105        } while (!(((ptstat >> domain) & 1) == 0));
 106
 107        do {
 108                mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
 109        } while (!((mdstat & MDSTAT_STATE_MASK) == next_state));
 110
 111        iounmap(psc_base);
 112}
 113