xref: /linux/arch/arm/mach-imx/src.c (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2011 Freescale Semiconductor, Inc.
4  * Copyright 2011 Linaro Ltd.
5  */
6 
7 #include <linux/init.h>
8 #include <linux/io.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/reset-controller.h>
12 #include <linux/smp.h>
13 #include <asm/smp_plat.h>
14 #include "common.h"
15 
16 #define SRC_SCR				0x000
17 #define SRC_GPR1			0x020
18 #define BP_SRC_SCR_WARM_RESET_ENABLE	0
19 #define BP_SRC_SCR_SW_GPU_RST		1
20 #define BP_SRC_SCR_SW_VPU_RST		2
21 #define BP_SRC_SCR_SW_IPU1_RST		3
22 #define BP_SRC_SCR_SW_OPEN_VG_RST	4
23 #define BP_SRC_SCR_SW_IPU2_RST		12
24 #define BP_SRC_SCR_CORE1_RST		14
25 #define BP_SRC_SCR_CORE1_ENABLE		22
26 
27 static void __iomem *src_base;
28 static DEFINE_SPINLOCK(scr_lock);
29 
30 static const int sw_reset_bits[5] = {
31 	BP_SRC_SCR_SW_GPU_RST,
32 	BP_SRC_SCR_SW_VPU_RST,
33 	BP_SRC_SCR_SW_IPU1_RST,
34 	BP_SRC_SCR_SW_OPEN_VG_RST,
35 	BP_SRC_SCR_SW_IPU2_RST
36 };
37 
38 static int imx_src_reset_module(struct reset_controller_dev *rcdev,
39 		unsigned long sw_reset_idx)
40 {
41 	unsigned long timeout;
42 	unsigned long flags;
43 	int bit;
44 	u32 val;
45 
46 	if (sw_reset_idx >= ARRAY_SIZE(sw_reset_bits))
47 		return -EINVAL;
48 
49 	bit = 1 << sw_reset_bits[sw_reset_idx];
50 
51 	spin_lock_irqsave(&scr_lock, flags);
52 	val = readl_relaxed(src_base + SRC_SCR);
53 	val |= bit;
54 	writel_relaxed(val, src_base + SRC_SCR);
55 	spin_unlock_irqrestore(&scr_lock, flags);
56 
57 	timeout = jiffies + msecs_to_jiffies(1000);
58 	while (readl(src_base + SRC_SCR) & bit) {
59 		if (time_after(jiffies, timeout))
60 			return -ETIME;
61 		cpu_relax();
62 	}
63 
64 	return 0;
65 }
66 
67 static const struct reset_control_ops imx_src_ops = {
68 	.reset = imx_src_reset_module,
69 };
70 
71 static struct reset_controller_dev imx_reset_controller = {
72 	.ops = &imx_src_ops,
73 	.nr_resets = ARRAY_SIZE(sw_reset_bits),
74 };
75 
76 void imx_enable_cpu(int cpu, bool enable)
77 {
78 	u32 mask, val;
79 
80 	cpu = cpu_logical_map(cpu);
81 	mask = 1 << (BP_SRC_SCR_CORE1_ENABLE + cpu - 1);
82 	spin_lock(&scr_lock);
83 	val = readl_relaxed(src_base + SRC_SCR);
84 	val = enable ? val | mask : val & ~mask;
85 	val |= 1 << (BP_SRC_SCR_CORE1_RST + cpu - 1);
86 	writel_relaxed(val, src_base + SRC_SCR);
87 	spin_unlock(&scr_lock);
88 }
89 
90 void imx_set_cpu_jump(int cpu, void *jump_addr)
91 {
92 	cpu = cpu_logical_map(cpu);
93 	writel_relaxed(__pa_symbol(jump_addr),
94 		       src_base + SRC_GPR1 + cpu * 8);
95 }
96 
97 u32 imx_get_cpu_arg(int cpu)
98 {
99 	cpu = cpu_logical_map(cpu);
100 	return readl_relaxed(src_base + SRC_GPR1 + cpu * 8 + 4);
101 }
102 
103 void imx_set_cpu_arg(int cpu, u32 arg)
104 {
105 	cpu = cpu_logical_map(cpu);
106 	writel_relaxed(arg, src_base + SRC_GPR1 + cpu * 8 + 4);
107 }
108 
109 void __init imx_src_init(void)
110 {
111 	struct device_node *np;
112 	u32 val;
113 
114 	np = of_find_compatible_node(NULL, NULL, "fsl,imx51-src");
115 	if (!np)
116 		return;
117 	src_base = of_iomap(np, 0);
118 	WARN_ON(!src_base);
119 
120 	imx_reset_controller.of_node = np;
121 	if (IS_ENABLED(CONFIG_RESET_CONTROLLER))
122 		reset_controller_register(&imx_reset_controller);
123 
124 	/*
125 	 * force warm reset sources to generate cold reset
126 	 * for a more reliable restart
127 	 */
128 	spin_lock(&scr_lock);
129 	val = readl_relaxed(src_base + SRC_SCR);
130 	val &= ~(1 << BP_SRC_SCR_WARM_RESET_ENABLE);
131 	writel_relaxed(val, src_base + SRC_SCR);
132 	spin_unlock(&scr_lock);
133 }
134