1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * omap2-restart.c - code common to all OMAP2xxx machines.
4 *
5 * Copyright (C) 2012 Texas Instruments
6 * Paul Walmsley
7 */
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12
13 #include "soc.h"
14 #include "common.h"
15 #include "prm.h"
16
17 /*
18 * reset_virt_prcm_set_ck, reset_sys_ck: pointers to the virt_prcm_set
19 * clock and the sys_ck. Used during the reset process
20 */
21 static struct clk *reset_virt_prcm_set_ck, *reset_sys_ck;
22
23 /* Reboot handling */
24
25 /**
26 * omap2xxx_restart - Set DPLL to bypass mode for reboot to work
27 *
28 * Set the DPLL to bypass so that reboot completes successfully. No
29 * return value.
30 */
31 void omap2xxx_restart(enum reboot_mode mode, const char *cmd)
32 {
33 u32 rate;
34
35 rate = clk_get_rate(reset_sys_ck);
36 clk_set_rate(reset_virt_prcm_set_ck, rate);
37
38 /* XXX Should save the cmd argument for use after the reboot */
39
40 omap_prm_reset_system();
41 }
42
43 /**
44 * omap2xxx_common_look_up_clks_for_reset - look up clocks needed for restart
45 *
46 * Some clocks need to be looked up in advance for the SoC restart
47 * operation to work - see omap2xxx_restart(). Returns -EINVAL upon
48 * error or 0 upon success.
49 */
50 static int __init omap2xxx_common_look_up_clks_for_reset(void)
51 {
52 reset_virt_prcm_set_ck = clk_get(NULL, "virt_prcm_set");
53 if (IS_ERR(reset_virt_prcm_set_ck))
54 return -EINVAL;
55
56 reset_sys_ck = clk_get(NULL, "sys_ck");
57 if (IS_ERR(reset_sys_ck))
58 return -EINVAL;
59
60 return 0;
61 }
62 omap_postcore_initcall(omap2xxx_common_look_up_clks_for_reset);
63
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.