OpenCloudOS-Kernel/arch/arm/mach-omap2/omap2-restart.c

66 lines
1.7 KiB
C

/*
* omap2-restart.c - code common to all OMAP2xxx machines.
*
* Copyright (C) 2012 Texas Instruments
* Paul Walmsley
*
* 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/init.h>
#include <linux/clk.h>
#include <linux/io.h>
#include "soc.h"
#include "common.h"
#include "prm.h"
/*
* reset_virt_prcm_set_ck, reset_sys_ck: pointers to the virt_prcm_set
* clock and the sys_ck. Used during the reset process
*/
static struct clk *reset_virt_prcm_set_ck, *reset_sys_ck;
/* Reboot handling */
/**
* omap2xxx_restart - Set DPLL to bypass mode for reboot to work
*
* Set the DPLL to bypass so that reboot completes successfully. No
* return value.
*/
void omap2xxx_restart(enum reboot_mode mode, const char *cmd)
{
u32 rate;
rate = clk_get_rate(reset_sys_ck);
clk_set_rate(reset_virt_prcm_set_ck, rate);
/* XXX Should save the cmd argument for use after the reboot */
omap_prm_reset_system();
}
/**
* omap2xxx_common_look_up_clks_for_reset - look up clocks needed for restart
*
* Some clocks need to be looked up in advance for the SoC restart
* operation to work - see omap2xxx_restart(). Returns -EINVAL upon
* error or 0 upon success.
*/
static int __init omap2xxx_common_look_up_clks_for_reset(void)
{
reset_virt_prcm_set_ck = clk_get(NULL, "virt_prcm_set");
if (IS_ERR(reset_virt_prcm_set_ck))
return -EINVAL;
reset_sys_ck = clk_get(NULL, "sys_ck");
if (IS_ERR(reset_sys_ck))
return -EINVAL;
return 0;
}
omap_postcore_initcall(omap2xxx_common_look_up_clks_for_reset);