LXR linux/arch/arm/mach-msm/idle.c

   1/* arch/arm/mach-msm/idle.c
   2 *
   3 * Idle processing for MSM7K - work around bugs with SWFI.
   4 *
   5 * Copyright (c) 2007 QUALCOMM Incorporated.
   6 * Copyright (C) 2007 Google, Inc.
   7 *
   8 * This software is licensed under the terms of the GNU General Public
   9 * License version 2, as published by the Free Software Foundation, and
  10 * may be copied, distributed, and modified under those terms.
  11 *
  12 * This program is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 * GNU General Public License for more details.
  16 *
  17 */
  18
  19#include <linux/init.h>
  20#include <asm/system.h>
  21
  22static void msm_idle(void)
  23{
  24#ifdef CONFIG_MSM7X00A_IDLE
  25        asm volatile (
  26
  27        "mrc     p15, 0, r1, c1, c0, 0    /* read current CR    */ \n\t"
  28        "bic     r0, r1, #(1 << 2)        /* clear dcache bit   */ \n\t"
  29        "bic     r0, r0, #(1 << 12)       /* clear icache bit   */ \n\t"
  30        "mcr     p15, 0, r0, c1, c0, 0    /* disable d/i cache  */ \n\t"
  31
  32        "mov     r0, #0                   /* prepare wfi value  */ \n\t"
  33        "mcr     p15, 0, r0, c7, c10, 0   /* flush the cache    */ \n\t"
  34        "mcr     p15, 0, r0, c7, c10, 4   /* memory barrier     */ \n\t"
  35        "mcr     p15, 0, r0, c7, c0, 4    /* wait for interrupt */ \n\t"
  36
  37        "mcr     p15, 0, r1, c1, c0, 0    /* restore d/i cache  */ \n\t"
  38
  39        : : : "r0","r1" );
  40#endif
  41}
  42
  43static int __init msm_idle_init(void)
  44{
  45        arm_pm_idle = msm_idle;
  46        return 0;
  47}
  48
  49arch_initcall(msm_idle_init);
  50