arch/mips/alchemy/common/power.c

   1 /*
   2  * BRIEF MODULE DESCRIPTION
   3  *      Au1xx0 Power Management routines.
   4  *
   5  * Copyright 2001, 2008 MontaVista Software Inc.
   6  * Author: MontaVista Software, Inc. <source@mvista.com>
   7  *
   8  *  Some of the routines are right out of init/main.c, whose
   9  *  copyrights apply here.
  10  *
  11  *  This program is free software; you can redistribute  it and/or modify it
  12  *  under  the terms of  the GNU General  Public License as published by the
  13  *  Free Software Foundation;  either version 2 of the  License, or (at your
  14  *  option) any later version.
  15  *
  16  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
  17  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
  18  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
  19  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
  20  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
  22  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  23  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
  24  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  *
  27  *  You should have received a copy of the  GNU General Public License along
  28  *  with this program; if not, write  to the Free Software Foundation, Inc.,
  29  *  675 Mass Ave, Cambridge, MA 02139, USA.
  30  */
  31
  32 #include <linux/init.h>
  33 #include <linux/pm.h>
  34 #include <linux/sysctl.h>
  35 #include <linux/jiffies.h>
  36
  37 #include <asm/uaccess.h>
  38 #include <asm/mach-au1x00/au1000.h>
  39
  40 /*
  41  * We need to save/restore a bunch of core registers that are
  42  * either volatile or reset to some state across a processor sleep.
  43  * If reading a register doesn't provide a proper result for a
  44  * later restore, we have to provide a function for loading that
  45  * register and save a copy.
  46  *
  47  * We only have to save/restore registers that aren't otherwise
  48  * done as part of a driver pm_* function.
  49  */
  50 static unsigned int sleep_sys_clocks[5];
  51 static unsigned int sleep_sys_pinfunc;
  52 static unsigned int sleep_static_memctlr[4][3];
  53
  54
  55 static void save_core_regs(void)
  56 {
  57         /* Clocks and PLLs. */
  58         sleep_sys_clocks[0] = au_readl(SYS_FREQCTRL0);
  59         sleep_sys_clocks[1] = au_readl(SYS_FREQCTRL1);
  60         sleep_sys_clocks[2] = au_readl(SYS_CLKSRC);
  61         sleep_sys_clocks[3] = au_readl(SYS_CPUPLL);
  62         sleep_sys_clocks[4] = au_readl(SYS_AUXPLL);
  63
  64         /* pin mux config */
  65         sleep_sys_pinfunc = au_readl(SYS_PINFUNC);
  66
  67         /* Save the static memory controller configuration. */
  68         sleep_static_memctlr[0][0] = au_readl(MEM_STCFG0);
  69         sleep_static_memctlr[0][1] = au_readl(MEM_STTIME0);
  70         sleep_static_memctlr[0][2] = au_readl(MEM_STADDR0);
  71         sleep_static_memctlr[1][0] = au_readl(MEM_STCFG1);
  72         sleep_static_memctlr[1][1] = au_readl(MEM_STTIME1);
  73         sleep_static_memctlr[1][2] = au_readl(MEM_STADDR1);
  74         sleep_static_memctlr[2][0] = au_readl(MEM_STCFG2);
  75         sleep_static_memctlr[2][1] = au_readl(MEM_STTIME2);
  76         sleep_static_memctlr[2][2] = au_readl(MEM_STADDR2);
  77         sleep_static_memctlr[3][0] = au_readl(MEM_STCFG3);
  78         sleep_static_memctlr[3][1] = au_readl(MEM_STTIME3);
  79         sleep_static_memctlr[3][2] = au_readl(MEM_STADDR3);
  80 }
  81
  82 static void restore_core_regs(void)
  83 {
  84         /* restore clock configuration.  Writing CPUPLL last will
  85          * stall a bit and stabilize other clocks (unless this is
  86          * one of those Au1000 with a write-only PLL, where we dont
  87          * have a valid value)
  88          */
  89         au_writel(sleep_sys_clocks[0], SYS_FREQCTRL0);
  90         au_writel(sleep_sys_clocks[1], SYS_FREQCTRL1);
  91         au_writel(sleep_sys_clocks[2], SYS_CLKSRC);
  92         au_writel(sleep_sys_clocks[4], SYS_AUXPLL);
  93         if (!au1xxx_cpu_has_pll_wo())
  94                 au_writel(sleep_sys_clocks[3], SYS_CPUPLL);
  95         au_sync();
  96
  97         au_writel(sleep_sys_pinfunc, SYS_PINFUNC);
  98         au_sync();
  99
 100         /* Restore the static memory controller configuration. */
 101         au_writel(sleep_static_memctlr[0][0], MEM_STCFG0);
 102         au_writel(sleep_static_memctlr[0][1], MEM_STTIME0);
 103         au_writel(sleep_static_memctlr[0][2], MEM_STADDR0);
 104         au_writel(sleep_static_memctlr[1][0], MEM_STCFG1);
 105         au_writel(sleep_static_memctlr[1][1], MEM_STTIME1);
 106         au_writel(sleep_static_memctlr[1][2], MEM_STADDR1);
 107         au_writel(sleep_static_memctlr[2][0], MEM_STCFG2);
 108         au_writel(sleep_static_memctlr[2][1], MEM_STTIME2);
 109         au_writel(sleep_static_memctlr[2][2], MEM_STADDR2);
 110         au_writel(sleep_static_memctlr[3][0], MEM_STCFG3);
 111         au_writel(sleep_static_memctlr[3][1], MEM_STTIME3);
 112         au_writel(sleep_static_memctlr[3][2], MEM_STADDR3);
 113 }
 114
 115 void au_sleep(void)
 116 {
 117         save_core_regs();
 118
 119         switch (alchemy_get_cputype()) {
 120         case ALCHEMY_CPU_AU1000:
 121         case ALCHEMY_CPU_AU1500:
 122         case ALCHEMY_CPU_AU1100:
 123                 alchemy_sleep_au1000();
 124                 break;
 125         case ALCHEMY_CPU_AU1550:
 126         case ALCHEMY_CPU_AU1200:
 127                 alchemy_sleep_au1550();
 128                 break;
 129         }
 130
 131         restore_core_regs();
 132 }