1 /*
2  * System controller support for Armada 370, 375 and XP platforms.
3  *
4  * Copyright (C) 2012 Marvell
5  *
6  * Lior Amsalem <alior@marvell.com>
7  * Gregory CLEMENT <gregory.clement@free-electrons.com>
8  * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
9  *
10  * This file is licensed under the terms of the GNU General Public
11  * License version 2.  This program is licensed "as is" without any
12  * warranty of any kind, whether express or implied.
13  *
14  * The Armada 370, 375 and Armada XP SoCs have a range of
15  * miscellaneous registers, that do not belong to a particular device,
16  * but rather provide system-level features. This basic
17  * system-controller driver provides a device tree binding for those
18  * registers, and implements utility functions offering various
19  * features related to those registers.
20  *
21  * For now, the feature set is limited to restarting the platform by a
22  * soft-reset, but it might be extended in the future.
23  */
24 
25 #include <linux/kernel.h>
26 #include <linux/init.h>
27 #include <linux/of_address.h>
28 #include <linux/io.h>
29 #include <linux/reboot.h>
30 #include "common.h"
31 #include "mvebu-soc-id.h"
32 #include "pmsu.h"
33 
34 #define ARMADA_375_CRYPT0_ENG_TARGET 41
35 #define ARMADA_375_CRYPT0_ENG_ATTR    1
36 
37 static void __iomem *system_controller_base;
38 static phys_addr_t system_controller_phys_base;
39 
40 struct mvebu_system_controller {
41 	u32 rstoutn_mask_offset;
42 	u32 system_soft_reset_offset;
43 
44 	u32 rstoutn_mask_reset_out_en;
45 	u32 system_soft_reset;
46 
47 	u32 resume_boot_addr;
48 
49 	u32 dev_id;
50 	u32 rev_id;
51 };
52 static struct mvebu_system_controller *mvebu_sc;
53 
54 static const struct mvebu_system_controller armada_370_xp_system_controller = {
55 	.rstoutn_mask_offset = 0x60,
56 	.system_soft_reset_offset = 0x64,
57 	.rstoutn_mask_reset_out_en = 0x1,
58 	.system_soft_reset = 0x1,
59 	.dev_id = 0x38,
60 	.rev_id = 0x3c,
61 };
62 
63 static const struct mvebu_system_controller armada_375_system_controller = {
64 	.rstoutn_mask_offset = 0x54,
65 	.system_soft_reset_offset = 0x58,
66 	.rstoutn_mask_reset_out_en = 0x1,
67 	.system_soft_reset = 0x1,
68 	.resume_boot_addr = 0xd4,
69 	.dev_id = 0x38,
70 	.rev_id = 0x3c,
71 };
72 
73 static const struct mvebu_system_controller orion_system_controller = {
74 	.rstoutn_mask_offset = 0x108,
75 	.system_soft_reset_offset = 0x10c,
76 	.rstoutn_mask_reset_out_en = 0x4,
77 	.system_soft_reset = 0x1,
78 };
79 
80 static const struct of_device_id of_system_controller_table[] = {
81 	{
82 		.compatible = "marvell,orion-system-controller",
83 		.data = (void *) &orion_system_controller,
84 	}, {
85 		.compatible = "marvell,armada-370-xp-system-controller",
86 		.data = (void *) &armada_370_xp_system_controller,
87 	}, {
88 		.compatible = "marvell,armada-375-system-controller",
89 		.data = (void *) &armada_375_system_controller,
90 	},
91 	{ /* end of list */ },
92 };
93 
94 void mvebu_restart(enum reboot_mode mode, const char *cmd)
95 {
96 	if (!system_controller_base) {
97 		pr_err("Cannot restart, system-controller not available: check the device tree\n");
98 	} else {
99 		/*
100 		 * Enable soft reset to assert RSTOUTn.
101 		 */
102 		writel(mvebu_sc->rstoutn_mask_reset_out_en,
103 			system_controller_base +
104 			mvebu_sc->rstoutn_mask_offset);
105 		/*
106 		 * Assert soft reset.
107 		 */
108 		writel(mvebu_sc->system_soft_reset,
109 			system_controller_base +
110 			mvebu_sc->system_soft_reset_offset);
111 	}
112 
113 	while (1)
114 		;
115 }
116 
117 int mvebu_system_controller_get_soc_id(u32 *dev, u32 *rev)
118 {
119 	if (of_machine_is_compatible("marvell,armada380") &&
120 		system_controller_base) {
121 		*dev = readl(system_controller_base + mvebu_sc->dev_id) >> 16;
122 		*rev = (readl(system_controller_base + mvebu_sc->rev_id) >> 8)
123 			& 0xF;
124 		return 0;
125 	} else
126 		return -ENODEV;
127 }
128 
129 #if defined(CONFIG_SMP) && defined(CONFIG_MACH_MVEBU_V7)
130 static void mvebu_armada375_smp_wa_init(void)
131 {
132 	u32 dev, rev;
133 	phys_addr_t resume_addr_reg;
134 
135 	if (mvebu_get_soc_id(&dev, &rev) != 0)
136 		return;
137 
138 	if (rev != ARMADA_375_Z1_REV)
139 		return;
140 
141 	resume_addr_reg = system_controller_phys_base +
142 		mvebu_sc->resume_boot_addr;
143 	mvebu_setup_boot_addr_wa(ARMADA_375_CRYPT0_ENG_TARGET,
144 				 ARMADA_375_CRYPT0_ENG_ATTR,
145 				 resume_addr_reg);
146 }
147 
148 void mvebu_system_controller_set_cpu_boot_addr(void *boot_addr)
149 {
150 	BUG_ON(system_controller_base == NULL);
151 	BUG_ON(mvebu_sc->resume_boot_addr == 0);
152 
153 	if (of_machine_is_compatible("marvell,armada375"))
154 		mvebu_armada375_smp_wa_init();
155 
156 	writel(__pa_symbol(boot_addr), system_controller_base +
157 	       mvebu_sc->resume_boot_addr);
158 }
159 #endif
160 
161 static int __init mvebu_system_controller_init(void)
162 {
163 	const struct of_device_id *match;
164 	struct device_node *np;
165 
166 	np = of_find_matching_node_and_match(NULL, of_system_controller_table,
167 					     &match);
168 	if (np) {
169 		struct resource res;
170 		system_controller_base = of_iomap(np, 0);
171 		of_address_to_resource(np, 0, &res);
172 		system_controller_phys_base = res.start;
173 		mvebu_sc = (struct mvebu_system_controller *)match->data;
174 		of_node_put(np);
175 	}
176 
177 	return 0;
178 }
179 
180 early_initcall(mvebu_system_controller_init);
181