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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2018-2019, Intel Corporation.
4 * Copyright (C) 2012 Freescale Semiconductor, Inc.
5 * Copyright (C) 2012 Linaro Ltd.
6 *
7 * Based on syscon driver.
8 */
9
10#include <linux/arm-smccc.h>
11#include <linux/err.h>
12#include <linux/io.h>
13#include <linux/mfd/altera-sysmgr.h>
14#include <linux/mfd/syscon.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_platform.h>
19#include <linux/regmap.h>
20#include <linux/slab.h>
21
22/**
23 * struct altr_sysmgr - Altera SOCFPGA System Manager
24 * @regmap: the regmap used for System Manager accesses.
25 */
26struct altr_sysmgr {
27 struct regmap *regmap;
28};
29
30static struct platform_driver altr_sysmgr_driver;
31
32/**
33 * s10_protected_reg_write
34 * Write to a protected SMC register.
35 * @base: Base address of System Manager
36 * @reg: Address offset of register
37 * @val: Value to write
38 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success
39 * INTEL_SIP_SMC_REG_ERROR on error
40 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported
41 */
42static int s10_protected_reg_write(void *base,
43 unsigned int reg, unsigned int val)
44{
45 struct arm_smccc_res result;
46 unsigned long sysmgr_base = (unsigned long)base;
47
48 arm_smccc_smc(INTEL_SIP_SMC_REG_WRITE, sysmgr_base + reg,
49 val, 0, 0, 0, 0, 0, &result);
50
51 return (int)result.a0;
52}
53
54/**
55 * s10_protected_reg_read
56 * Read the status of a protected SMC register
57 * @base: Base address of System Manager.
58 * @reg: Address of register
59 * @val: Value read.
60 * Return: INTEL_SIP_SMC_STATUS_OK (0) on success
61 * INTEL_SIP_SMC_REG_ERROR on error
62 * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported
63 */
64static int s10_protected_reg_read(void *base,
65 unsigned int reg, unsigned int *val)
66{
67 struct arm_smccc_res result;
68 unsigned long sysmgr_base = (unsigned long)base;
69
70 arm_smccc_smc(INTEL_SIP_SMC_REG_READ, sysmgr_base + reg,
71 0, 0, 0, 0, 0, 0, &result);
72
73 *val = (unsigned int)result.a1;
74
75 return (int)result.a0;
76}
77
78static struct regmap_config altr_sysmgr_regmap_cfg = {
79 .name = "altr_sysmgr",
80 .reg_bits = 32,
81 .reg_stride = 4,
82 .val_bits = 32,
83 .fast_io = true,
84 .use_single_read = true,
85 .use_single_write = true,
86};
87
88/**
89 * altr_sysmgr_regmap_lookup_by_phandle
90 * Find the sysmgr previous configured in probe() and return regmap property.
91 * Return: regmap if found or error if not found.
92 *
93 * @np: Pointer to device's Device Tree node
94 * @property: Device Tree property name which references the sysmgr
95 */
96struct regmap *altr_sysmgr_regmap_lookup_by_phandle(struct device_node *np,
97 const char *property)
98{
99 struct device *dev;
100 struct altr_sysmgr *sysmgr;
101 struct device_node *sysmgr_np;
102
103 if (property)
104 sysmgr_np = of_parse_phandle(np, property, 0);
105 else
106 sysmgr_np = np;
107
108 if (!sysmgr_np)
109 return ERR_PTR(-ENODEV);
110
111 dev = driver_find_device_by_of_node(&altr_sysmgr_driver.driver,
112 (void *)sysmgr_np);
113 of_node_put(sysmgr_np);
114 if (!dev)
115 return ERR_PTR(-EPROBE_DEFER);
116
117 sysmgr = dev_get_drvdata(dev);
118
119 return sysmgr->regmap;
120}
121EXPORT_SYMBOL_GPL(altr_sysmgr_regmap_lookup_by_phandle);
122
123static int sysmgr_probe(struct platform_device *pdev)
124{
125 struct altr_sysmgr *sysmgr;
126 struct regmap *regmap;
127 struct resource *res;
128 struct regmap_config sysmgr_config = altr_sysmgr_regmap_cfg;
129 struct device *dev = &pdev->dev;
130 struct device_node *np = dev->of_node;
131 void __iomem *base;
132
133 sysmgr = devm_kzalloc(dev, sizeof(*sysmgr), GFP_KERNEL);
134 if (!sysmgr)
135 return -ENOMEM;
136
137 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
138 if (!res)
139 return -ENOENT;
140
141 sysmgr_config.max_register = resource_size(res) -
142 sysmgr_config.reg_stride;
143 if (of_device_is_compatible(np, "altr,sys-mgr-s10")) {
144 sysmgr_config.reg_read = s10_protected_reg_read;
145 sysmgr_config.reg_write = s10_protected_reg_write;
146
147 /* Need physical address for SMCC call */
148 regmap = devm_regmap_init(dev, NULL, (void *)res->start,
149 &sysmgr_config);
150 } else {
151 base = devm_ioremap(dev, res->start, resource_size(res));
152 if (!base)
153 return -ENOMEM;
154
155 sysmgr_config.max_register = res->end - res->start - 3;
156 regmap = devm_regmap_init_mmio(dev, base, &sysmgr_config);
157 }
158
159 if (IS_ERR(regmap)) {
160 pr_err("regmap init failed\n");
161 return PTR_ERR(regmap);
162 }
163
164 sysmgr->regmap = regmap;
165
166 platform_set_drvdata(pdev, sysmgr);
167
168 return 0;
169}
170
171static const struct of_device_id altr_sysmgr_of_match[] = {
172 { .compatible = "altr,sys-mgr" },
173 { .compatible = "altr,sys-mgr-s10" },
174 {},
175};
176MODULE_DEVICE_TABLE(of, altr_sysmgr_of_match);
177
178static struct platform_driver altr_sysmgr_driver = {
179 .probe = sysmgr_probe,
180 .driver = {
181 .name = "altr,system_manager",
182 .of_match_table = altr_sysmgr_of_match,
183 },
184};
185
186static int __init altr_sysmgr_init(void)
187{
188 return platform_driver_register(&altr_sysmgr_driver);
189}
190core_initcall(altr_sysmgr_init);
191
192static void __exit altr_sysmgr_exit(void)
193{
194 platform_driver_unregister(&altr_sysmgr_driver);
195}
196module_exit(altr_sysmgr_exit);
197
198MODULE_AUTHOR("Thor Thayer <>");
199MODULE_DESCRIPTION("SOCFPGA System Manager driver");
200MODULE_LICENSE("GPL v2");