1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // |
3 | // Copyright (C) 2013 Samsung Electronics Co., Ltd. |
4 | // Tomasz Figa <t.figa@samsung.com> |
5 | // Copyright (C) 2008 Openmoko, Inc. |
6 | // Copyright (C) 2004-2008 Simtec Electronics |
7 | // Ben Dooks <ben@simtec.co.uk> |
8 | // http://armlinux.simtec.co.uk/ |
9 | // |
10 | // Samsung common power management helper functions. |
11 | |
12 | #include <linux/io.h> |
13 | #include <linux/kernel.h> |
14 | |
15 | #include "pm-common.h" |
16 | |
17 | /* helper functions to save and restore register state */ |
18 | |
19 | /** |
20 | * s3c_pm_do_save() - save a set of registers for restoration on resume. |
21 | * @ptr: Pointer to an array of registers. |
22 | * @count: Size of the ptr array. |
23 | * |
24 | * Run through the list of registers given, saving their contents in the |
25 | * array for later restoration when we wakeup. |
26 | */ |
27 | void s3c_pm_do_save(struct sleep_save *ptr, int count) |
28 | { |
29 | for (; count > 0; count--, ptr++) { |
30 | ptr->val = readl_relaxed(ptr->reg); |
31 | S3C_PMDBG("saved %p value %08lx\n" , ptr->reg, ptr->val); |
32 | } |
33 | } |
34 | |
35 | /** |
36 | * s3c_pm_do_restore() - restore register values from the save list. |
37 | * @ptr: Pointer to an array of registers. |
38 | * @count: Size of the ptr array. |
39 | * |
40 | * Restore the register values saved from s3c_pm_do_save(). |
41 | * |
42 | * Note, we do not use S3C_PMDBG() in here, as the system may not have |
43 | * restore the UARTs state yet |
44 | */ |
45 | |
46 | void s3c_pm_do_restore(const struct sleep_save *ptr, int count) |
47 | { |
48 | for (; count > 0; count--, ptr++) { |
49 | pr_debug("restore %p (restore %08lx, was %08x)\n" , |
50 | ptr->reg, ptr->val, readl_relaxed(ptr->reg)); |
51 | |
52 | writel_relaxed(ptr->val, ptr->reg); |
53 | } |
54 | } |
55 | |
56 | /** |
57 | * s3c_pm_do_restore_core() - early restore register values from save list. |
58 | * @ptr: Pointer to an array of registers. |
59 | * @count: Size of the ptr array. |
60 | * |
61 | * This is similar to s3c_pm_do_restore() except we try and minimise the |
62 | * side effects of the function in case registers that hardware might need |
63 | * to work has been restored. |
64 | * |
65 | * WARNING: Do not put any debug in here that may effect memory or use |
66 | * peripherals, as things may be changing! |
67 | */ |
68 | |
69 | void s3c_pm_do_restore_core(const struct sleep_save *ptr, int count) |
70 | { |
71 | for (; count > 0; count--, ptr++) |
72 | writel_relaxed(ptr->val, ptr->reg); |
73 | } |
74 | |