1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Driver for Xilinx TMR Inject IP. |
4 | * |
5 | * Copyright (C) 2022 Advanced Micro Devices, Inc. |
6 | * |
7 | * Description: |
8 | * This driver is developed for TMR Inject IP,The Triple Modular Redundancy(TMR) |
9 | * Inject provides fault injection. |
10 | */ |
11 | |
12 | #include <asm/xilinx_mb_manager.h> |
13 | #include <linux/module.h> |
14 | #include <linux/of.h> |
15 | #include <linux/platform_device.h> |
16 | #include <linux/fault-inject.h> |
17 | |
18 | /* TMR Inject Register offsets */ |
19 | #define XTMR_INJECT_CR_OFFSET 0x0 |
20 | #define XTMR_INJECT_AIR_OFFSET 0x4 |
21 | #define XTMR_INJECT_IIR_OFFSET 0xC |
22 | #define XTMR_INJECT_EAIR_OFFSET 0x10 |
23 | #define XTMR_INJECT_ERR_OFFSET 0x204 |
24 | |
25 | /* Register Bitmasks/shifts */ |
26 | #define XTMR_INJECT_CR_CPUID_SHIFT 8 |
27 | #define XTMR_INJECT_CR_IE_SHIFT 10 |
28 | #define XTMR_INJECT_IIR_ADDR_MASK GENMASK(31, 16) |
29 | |
30 | #define XTMR_INJECT_MAGIC_MAX_VAL 255 |
31 | |
32 | /** |
33 | * struct xtmr_inject_dev - Driver data for TMR Inject |
34 | * @regs: device physical base address |
35 | * @magic: Magic hardware configuration value |
36 | */ |
37 | struct xtmr_inject_dev { |
38 | void __iomem *regs; |
39 | u32 magic; |
40 | }; |
41 | |
42 | static DECLARE_FAULT_ATTR(inject_fault); |
43 | static char *inject_request; |
44 | module_param(inject_request, charp, 0); |
45 | MODULE_PARM_DESC(inject_request, "default fault injection attributes" ); |
46 | static struct dentry *dbgfs_root; |
47 | |
48 | /* IO accessors */ |
49 | static inline void xtmr_inject_write(struct xtmr_inject_dev *xtmr_inject, |
50 | u32 addr, u32 value) |
51 | { |
52 | iowrite32(value, xtmr_inject->regs + addr); |
53 | } |
54 | |
55 | static inline u32 xtmr_inject_read(struct xtmr_inject_dev *xtmr_inject, |
56 | u32 addr) |
57 | { |
58 | return ioread32(xtmr_inject->regs + addr); |
59 | } |
60 | |
61 | static int xtmr_inject_set(void *data, u64 val) |
62 | { |
63 | if (val != 1) |
64 | return -EINVAL; |
65 | |
66 | xmb_inject_err(); |
67 | return 0; |
68 | } |
69 | DEFINE_DEBUGFS_ATTRIBUTE(xtmr_inject_fops, NULL, xtmr_inject_set, "%llu\n" ); |
70 | |
71 | static void xtmr_init_debugfs(struct xtmr_inject_dev *xtmr_inject) |
72 | { |
73 | struct dentry *dir; |
74 | |
75 | dbgfs_root = debugfs_create_dir(name: "xtmr_inject" , NULL); |
76 | dir = fault_create_debugfs_attr(name: "inject_fault" , parent: dbgfs_root, |
77 | attr: &inject_fault); |
78 | debugfs_create_file(name: "inject_fault" , mode: 0200, parent: dir, NULL, |
79 | fops: &xtmr_inject_fops); |
80 | } |
81 | |
82 | static void xtmr_inject_init(struct xtmr_inject_dev *xtmr_inject) |
83 | { |
84 | u32 cr_val; |
85 | |
86 | if (inject_request) |
87 | setup_fault_attr(attr: &inject_fault, str: inject_request); |
88 | /* Allow fault injection */ |
89 | cr_val = xtmr_inject->magic | |
90 | (1 << XTMR_INJECT_CR_IE_SHIFT) | |
91 | (1 << XTMR_INJECT_CR_CPUID_SHIFT); |
92 | xtmr_inject_write(xtmr_inject, XTMR_INJECT_CR_OFFSET, |
93 | value: cr_val); |
94 | /* Initialize the address inject and instruction inject registers */ |
95 | xtmr_inject_write(xtmr_inject, XTMR_INJECT_AIR_OFFSET, |
96 | value: XMB_INJECT_ERR_OFFSET); |
97 | xtmr_inject_write(xtmr_inject, XTMR_INJECT_IIR_OFFSET, |
98 | value: XMB_INJECT_ERR_OFFSET & XTMR_INJECT_IIR_ADDR_MASK); |
99 | } |
100 | |
101 | /** |
102 | * xtmr_inject_probe - Driver probe function |
103 | * @pdev: Pointer to the platform_device structure |
104 | * |
105 | * This is the driver probe routine. It does all the memory |
106 | * allocation for the device. |
107 | * |
108 | * Return: 0 on success and failure value on error |
109 | */ |
110 | static int xtmr_inject_probe(struct platform_device *pdev) |
111 | { |
112 | struct xtmr_inject_dev *xtmr_inject; |
113 | int err; |
114 | |
115 | xtmr_inject = devm_kzalloc(dev: &pdev->dev, size: sizeof(*xtmr_inject), |
116 | GFP_KERNEL); |
117 | if (!xtmr_inject) |
118 | return -ENOMEM; |
119 | |
120 | xtmr_inject->regs = devm_platform_ioremap_resource(pdev, index: 0); |
121 | if (IS_ERR(ptr: xtmr_inject->regs)) |
122 | return PTR_ERR(ptr: xtmr_inject->regs); |
123 | |
124 | err = of_property_read_u32(np: pdev->dev.of_node, propname: "xlnx,magic" , |
125 | out_value: &xtmr_inject->magic); |
126 | if (err < 0) { |
127 | dev_err(&pdev->dev, "unable to read xlnx,magic property" ); |
128 | return err; |
129 | } |
130 | |
131 | if (xtmr_inject->magic > XTMR_INJECT_MAGIC_MAX_VAL) { |
132 | dev_err(&pdev->dev, "invalid xlnx,magic property value" ); |
133 | return -EINVAL; |
134 | } |
135 | |
136 | /* Initialize TMR Inject */ |
137 | xtmr_inject_init(xtmr_inject); |
138 | |
139 | xtmr_init_debugfs(xtmr_inject); |
140 | |
141 | platform_set_drvdata(pdev, data: xtmr_inject); |
142 | |
143 | return 0; |
144 | } |
145 | |
146 | static void xtmr_inject_remove(struct platform_device *pdev) |
147 | { |
148 | debugfs_remove_recursive(dentry: dbgfs_root); |
149 | dbgfs_root = NULL; |
150 | } |
151 | |
152 | static const struct of_device_id xtmr_inject_of_match[] = { |
153 | { |
154 | .compatible = "xlnx,tmr-inject-1.0" , |
155 | }, |
156 | { /* end of table */ } |
157 | }; |
158 | MODULE_DEVICE_TABLE(of, xtmr_inject_of_match); |
159 | |
160 | static struct platform_driver xtmr_inject_driver = { |
161 | .driver = { |
162 | .name = "xilinx-tmr_inject" , |
163 | .of_match_table = xtmr_inject_of_match, |
164 | }, |
165 | .probe = xtmr_inject_probe, |
166 | .remove_new = xtmr_inject_remove, |
167 | }; |
168 | module_platform_driver(xtmr_inject_driver); |
169 | MODULE_AUTHOR("Advanced Micro Devices, Inc" ); |
170 | MODULE_DESCRIPTION("Xilinx TMR Inject Driver" ); |
171 | MODULE_LICENSE("GPL" ); |
172 | |