xref: /OK3568_Linux_fs/kernel/drivers/clk/rockchip/softrst.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (c) 2014 MundoReader S.L.
4*4882a593Smuzhiyun  * Author: Heiko Stuebner <heiko@sntech.de>
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <linux/slab.h>
8*4882a593Smuzhiyun #include <linux/io.h>
9*4882a593Smuzhiyun #include <linux/reset-controller.h>
10*4882a593Smuzhiyun #include <linux/spinlock.h>
11*4882a593Smuzhiyun #include "clk.h"
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun struct rockchip_softrst {
14*4882a593Smuzhiyun 	struct reset_controller_dev	rcdev;
15*4882a593Smuzhiyun 	void __iomem			*reg_base;
16*4882a593Smuzhiyun 	int				num_regs;
17*4882a593Smuzhiyun 	int				num_per_reg;
18*4882a593Smuzhiyun 	u8				flags;
19*4882a593Smuzhiyun 	spinlock_t			lock;
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun 
rockchip_softrst_assert(struct reset_controller_dev * rcdev,unsigned long id)22*4882a593Smuzhiyun static int rockchip_softrst_assert(struct reset_controller_dev *rcdev,
23*4882a593Smuzhiyun 			      unsigned long id)
24*4882a593Smuzhiyun {
25*4882a593Smuzhiyun 	struct rockchip_softrst *softrst = container_of(rcdev,
26*4882a593Smuzhiyun 						     struct rockchip_softrst,
27*4882a593Smuzhiyun 						     rcdev);
28*4882a593Smuzhiyun 	int bank = id / softrst->num_per_reg;
29*4882a593Smuzhiyun 	int offset = id % softrst->num_per_reg;
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun 	if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
32*4882a593Smuzhiyun 		writel(BIT(offset) | (BIT(offset) << 16),
33*4882a593Smuzhiyun 		       softrst->reg_base + (bank * 4));
34*4882a593Smuzhiyun 	} else {
35*4882a593Smuzhiyun 		unsigned long flags;
36*4882a593Smuzhiyun 		u32 reg;
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun 		spin_lock_irqsave(&softrst->lock, flags);
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun 		reg = readl(softrst->reg_base + (bank * 4));
41*4882a593Smuzhiyun 		writel(reg | BIT(offset), softrst->reg_base + (bank * 4));
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun 		spin_unlock_irqrestore(&softrst->lock, flags);
44*4882a593Smuzhiyun 	}
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	return 0;
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun 
rockchip_softrst_deassert(struct reset_controller_dev * rcdev,unsigned long id)49*4882a593Smuzhiyun static int rockchip_softrst_deassert(struct reset_controller_dev *rcdev,
50*4882a593Smuzhiyun 				unsigned long id)
51*4882a593Smuzhiyun {
52*4882a593Smuzhiyun 	struct rockchip_softrst *softrst = container_of(rcdev,
53*4882a593Smuzhiyun 						     struct rockchip_softrst,
54*4882a593Smuzhiyun 						     rcdev);
55*4882a593Smuzhiyun 	int bank = id / softrst->num_per_reg;
56*4882a593Smuzhiyun 	int offset = id % softrst->num_per_reg;
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 	if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
59*4882a593Smuzhiyun 		writel((BIT(offset) << 16), softrst->reg_base + (bank * 4));
60*4882a593Smuzhiyun 	} else {
61*4882a593Smuzhiyun 		unsigned long flags;
62*4882a593Smuzhiyun 		u32 reg;
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 		spin_lock_irqsave(&softrst->lock, flags);
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 		reg = readl(softrst->reg_base + (bank * 4));
67*4882a593Smuzhiyun 		writel(reg & ~BIT(offset), softrst->reg_base + (bank * 4));
68*4882a593Smuzhiyun 
69*4882a593Smuzhiyun 		spin_unlock_irqrestore(&softrst->lock, flags);
70*4882a593Smuzhiyun 	}
71*4882a593Smuzhiyun 
72*4882a593Smuzhiyun 	return 0;
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun 
75*4882a593Smuzhiyun static const struct reset_control_ops rockchip_softrst_ops = {
76*4882a593Smuzhiyun 	.assert		= rockchip_softrst_assert,
77*4882a593Smuzhiyun 	.deassert	= rockchip_softrst_deassert,
78*4882a593Smuzhiyun };
79*4882a593Smuzhiyun 
rockchip_register_softrst(struct device_node * np,unsigned int num_regs,void __iomem * base,u8 flags)80*4882a593Smuzhiyun void rockchip_register_softrst(struct device_node *np,
81*4882a593Smuzhiyun 			       unsigned int num_regs,
82*4882a593Smuzhiyun 			       void __iomem *base, u8 flags)
83*4882a593Smuzhiyun {
84*4882a593Smuzhiyun 	struct rockchip_softrst *softrst;
85*4882a593Smuzhiyun 	int ret;
86*4882a593Smuzhiyun 
87*4882a593Smuzhiyun 	softrst = kzalloc(sizeof(*softrst), GFP_KERNEL);
88*4882a593Smuzhiyun 	if (!softrst)
89*4882a593Smuzhiyun 		return;
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun 	spin_lock_init(&softrst->lock);
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun 	softrst->reg_base = base;
94*4882a593Smuzhiyun 	softrst->flags = flags;
95*4882a593Smuzhiyun 	softrst->num_regs = num_regs;
96*4882a593Smuzhiyun 	softrst->num_per_reg = (flags & ROCKCHIP_SOFTRST_HIWORD_MASK) ? 16
97*4882a593Smuzhiyun 								      : 32;
98*4882a593Smuzhiyun 
99*4882a593Smuzhiyun 	softrst->rcdev.owner = THIS_MODULE;
100*4882a593Smuzhiyun 	softrst->rcdev.nr_resets =  num_regs * softrst->num_per_reg;
101*4882a593Smuzhiyun 	softrst->rcdev.ops = &rockchip_softrst_ops;
102*4882a593Smuzhiyun 	softrst->rcdev.of_node = np;
103*4882a593Smuzhiyun 	ret = reset_controller_register(&softrst->rcdev);
104*4882a593Smuzhiyun 	if (ret) {
105*4882a593Smuzhiyun 		pr_err("%s: could not register reset controller, %d\n",
106*4882a593Smuzhiyun 		       __func__, ret);
107*4882a593Smuzhiyun 		kfree(softrst);
108*4882a593Smuzhiyun 	}
109*4882a593Smuzhiyun };
110*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(rockchip_register_softrst);
111