summaryrefslogtreecommitdiff
path: root/drivers/power/reset/ocelot-reset.c
blob: f74e1dbb4ba3677436a2529996ae0a508f30e7ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
 * Microsemi MIPS SoC reset driver
 *
 * License: Dual MIT/GPL
 * Copyright (c) 2017 Microsemi Corporation
 */
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/notifier.h>
#include <linux/mfd/syscon.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/regmap.h>

struct reset_props {
	const char *syscon;
	u32 protect_reg;
	u32 vcore_protect;
	u32 if_si_owner_bit;
};

struct ocelot_reset_context {
	void __iomem *base;
	struct regmap *cpu_ctrl;
	const struct reset_props *props;
	struct notifier_block restart_handler;
};

#define SOFT_CHIP_RST BIT(0)

#define ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL	0x24
#define IF_SI_OWNER_MASK			GENMASK(1, 0)
#define IF_SI_OWNER_SISL			0
#define IF_SI_OWNER_SIBM			1
#define IF_SI_OWNER_SIMC			2

static int ocelot_restart_handle(struct notifier_block *this,
				 unsigned long mode, void *cmd)
{
	struct ocelot_reset_context *ctx = container_of(this, struct
							ocelot_reset_context,
							restart_handler);
	u32 if_si_owner_bit = ctx->props->if_si_owner_bit;

	/* Make sure the core is not protected from reset */
	regmap_update_bits(ctx->cpu_ctrl, ctx->props->protect_reg,
			   ctx->props->vcore_protect, 0);

	/* Make the SI back to boot mode */
	regmap_update_bits(ctx->cpu_ctrl, ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL,
			   IF_SI_OWNER_MASK << if_si_owner_bit,
			   IF_SI_OWNER_SIBM << if_si_owner_bit);

	pr_emerg("Resetting SoC\n");

	writel(SOFT_CHIP_RST, ctx->base);

	pr_emerg("Unable to restart system\n");
	return NOTIFY_DONE;
}

static int ocelot_reset_probe(struct platform_device *pdev)
{
	struct ocelot_reset_context *ctx;
	struct resource *res;

	struct device *dev = &pdev->dev;
	int err;

	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	ctx->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(ctx->base))
		return PTR_ERR(ctx->base);

	ctx->props = device_get_match_data(dev);

	ctx->cpu_ctrl = syscon_regmap_lookup_by_compatible(ctx->props->syscon);
	if (IS_ERR(ctx->cpu_ctrl)) {
		dev_err(dev, "No syscon map: %s\n", ctx->props->syscon);
		return PTR_ERR(ctx->cpu_ctrl);
	}

	ctx->restart_handler.notifier_call = ocelot_restart_handle;
	ctx->restart_handler.priority = 192;
	err = register_restart_handler(&ctx->restart_handler);
	if (err)
		dev_err(dev, "can't register restart notifier (err=%d)\n", err);

	return err;
}

static const struct reset_props reset_props_ocelot = {
	.syscon		 = "mscc,ocelot-cpu-syscon",
	.protect_reg     = 0x20,
	.vcore_protect   = BIT(2),
	.if_si_owner_bit = 4,
};

static const struct reset_props reset_props_sparx5 = {
	.syscon		 = "microchip,sparx5-cpu-syscon",
	.protect_reg     = 0x84,
	.vcore_protect   = BIT(10),
	.if_si_owner_bit = 6,
};

static const struct of_device_id ocelot_reset_of_match[] = {
	{
		.compatible = "mscc,ocelot-chip-reset",
		.data = &reset_props_ocelot
	}, {
		.compatible = "microchip,sparx5-chip-reset",
		.data = &reset_props_sparx5
	},
	{ /*sentinel*/ }
};

static struct platform_driver ocelot_reset_driver = {
	.probe = ocelot_reset_probe,
	.driver = {
		.name = "ocelot-chip-reset",
		.of_match_table = ocelot_reset_of_match,
	},
};
builtin_platform_driver(ocelot_reset_driver);