blob: 68423e26399d9ae8e618d506cdbb3c21cbbf0014 [file] [log] [blame]
Paul Walmsley2f334a32012-10-29 20:56:07 -06001/*
2 * omap2-restart.c - code common to all OMAP2xxx machines.
3 *
4 * Copyright (C) 2012 Texas Instruments
5 * Paul Walmsley
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/clk.h>
14#include <linux/io.h>
15
Tony Lindgrenb76c8b12013-01-11 11:24:18 -080016#include "soc.h"
Paul Walmsley2f334a32012-10-29 20:56:07 -060017#include "common.h"
18#include "prm2xxx.h"
19
20/*
21 * reset_virt_prcm_set_ck, reset_sys_ck: pointers to the virt_prcm_set
22 * clock and the sys_ck. Used during the reset process
23 */
24static struct clk *reset_virt_prcm_set_ck, *reset_sys_ck;
25
26/* Reboot handling */
27
28/**
29 * omap2xxx_restart - Set DPLL to bypass mode for reboot to work
30 *
31 * Set the DPLL to bypass so that reboot completes successfully. No
32 * return value.
33 */
Robin Holt7b6d8642013-07-08 16:01:40 -070034void omap2xxx_restart(enum reboot_mode mode, const char *cmd)
Paul Walmsley2f334a32012-10-29 20:56:07 -060035{
36 u32 rate;
37
38 rate = clk_get_rate(reset_sys_ck);
39 clk_set_rate(reset_virt_prcm_set_ck, rate);
40
41 /* XXX Should save the cmd argument for use after the reboot */
42
43 omap2xxx_prm_dpll_reset(); /* never returns */
44 while (1);
45}
46
47/**
48 * omap2xxx_common_look_up_clks_for_reset - look up clocks needed for restart
49 *
50 * Some clocks need to be looked up in advance for the SoC restart
51 * operation to work - see omap2xxx_restart(). Returns -EINVAL upon
52 * error or 0 upon success.
53 */
54static int __init omap2xxx_common_look_up_clks_for_reset(void)
55{
56 reset_virt_prcm_set_ck = clk_get(NULL, "virt_prcm_set");
57 if (IS_ERR(reset_virt_prcm_set_ck))
58 return -EINVAL;
59
60 reset_sys_ck = clk_get(NULL, "sys_ck");
61 if (IS_ERR(reset_sys_ck))
62 return -EINVAL;
63
64 return 0;
65}
Tony Lindgrenb76c8b12013-01-11 11:24:18 -080066omap_core_initcall(omap2xxx_common_look_up_clks_for_reset);