1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2014 MundoReader S.L.
4 * Author: Heiko Stuebner <heiko@sntech.de>
5 */
6
7 #include <linux/slab.h>
8 #include <linux/io.h>
9 #include <linux/reset-controller.h>
10 #include <linux/spinlock.h>
11 #include "clk.h"
12
13 struct rockchip_softrst {
14 struct reset_controller_dev rcdev;
15 void __iomem *reg_base;
16 int num_regs;
17 int num_per_reg;
18 u8 flags;
19 spinlock_t lock;
20 };
21
rockchip_softrst_assert(struct reset_controller_dev * rcdev,unsigned long id)22 static int rockchip_softrst_assert(struct reset_controller_dev *rcdev,
23 unsigned long id)
24 {
25 struct rockchip_softrst *softrst = container_of(rcdev,
26 struct rockchip_softrst,
27 rcdev);
28 int bank = id / softrst->num_per_reg;
29 int offset = id % softrst->num_per_reg;
30
31 if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
32 writel(BIT(offset) | (BIT(offset) << 16),
33 softrst->reg_base + (bank * 4));
34 } else {
35 unsigned long flags;
36 u32 reg;
37
38 spin_lock_irqsave(&softrst->lock, flags);
39
40 reg = readl(softrst->reg_base + (bank * 4));
41 writel(reg | BIT(offset), softrst->reg_base + (bank * 4));
42
43 spin_unlock_irqrestore(&softrst->lock, flags);
44 }
45
46 return 0;
47 }
48
rockchip_softrst_deassert(struct reset_controller_dev * rcdev,unsigned long id)49 static int rockchip_softrst_deassert(struct reset_controller_dev *rcdev,
50 unsigned long id)
51 {
52 struct rockchip_softrst *softrst = container_of(rcdev,
53 struct rockchip_softrst,
54 rcdev);
55 int bank = id / softrst->num_per_reg;
56 int offset = id % softrst->num_per_reg;
57
58 if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
59 writel((BIT(offset) << 16), softrst->reg_base + (bank * 4));
60 } else {
61 unsigned long flags;
62 u32 reg;
63
64 spin_lock_irqsave(&softrst->lock, flags);
65
66 reg = readl(softrst->reg_base + (bank * 4));
67 writel(reg & ~BIT(offset), softrst->reg_base + (bank * 4));
68
69 spin_unlock_irqrestore(&softrst->lock, flags);
70 }
71
72 return 0;
73 }
74
75 static const struct reset_control_ops rockchip_softrst_ops = {
76 .assert = rockchip_softrst_assert,
77 .deassert = rockchip_softrst_deassert,
78 };
79
rockchip_register_softrst(struct device_node * np,unsigned int num_regs,void __iomem * base,u8 flags)80 void rockchip_register_softrst(struct device_node *np,
81 unsigned int num_regs,
82 void __iomem *base, u8 flags)
83 {
84 struct rockchip_softrst *softrst;
85 int ret;
86
87 softrst = kzalloc(sizeof(*softrst), GFP_KERNEL);
88 if (!softrst)
89 return;
90
91 spin_lock_init(&softrst->lock);
92
93 softrst->reg_base = base;
94 softrst->flags = flags;
95 softrst->num_regs = num_regs;
96 softrst->num_per_reg = (flags & ROCKCHIP_SOFTRST_HIWORD_MASK) ? 16
97 : 32;
98
99 softrst->rcdev.owner = THIS_MODULE;
100 softrst->rcdev.nr_resets = num_regs * softrst->num_per_reg;
101 softrst->rcdev.ops = &rockchip_softrst_ops;
102 softrst->rcdev.of_node = np;
103 ret = reset_controller_register(&softrst->rcdev);
104 if (ret) {
105 pr_err("%s: could not register reset controller, %d\n",
106 __func__, ret);
107 kfree(softrst);
108 }
109 };
110 EXPORT_SYMBOL_GPL(rockchip_register_softrst);
111