1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2020 Linaro Ltd.
4 *
5 * This device driver implements MMIO TPM on SynQuacer Platform.
6 */
7 #include <linux/acpi.h>
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/slab.h>
11 #include <linux/of.h>
12 #include <linux/of_device.h>
13 #include <linux/kernel.h>
14 #include "tpm.h"
15 #include "tpm_tis_core.h"
16
17 /*
18 * irq > 0 means: use irq $irq;
19 * irq = 0 means: autoprobe for an irq;
20 * irq = -1 means: no irq support
21 */
22 struct tpm_tis_synquacer_info {
23 struct resource res;
24 int irq;
25 };
26
27 struct tpm_tis_synquacer_phy {
28 struct tpm_tis_data priv;
29 void __iomem *iobase;
30 };
31
to_tpm_tis_tcg_phy(struct tpm_tis_data * data)32 static inline struct tpm_tis_synquacer_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
33 {
34 return container_of(data, struct tpm_tis_synquacer_phy, priv);
35 }
36
tpm_tis_synquacer_read_bytes(struct tpm_tis_data * data,u32 addr,u16 len,u8 * result,enum tpm_tis_io_mode io_mode)37 static int tpm_tis_synquacer_read_bytes(struct tpm_tis_data *data, u32 addr,
38 u16 len, u8 *result,
39 enum tpm_tis_io_mode io_mode)
40 {
41 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
42 switch (io_mode) {
43 case TPM_TIS_PHYS_8:
44 while (len--)
45 *result++ = ioread8(phy->iobase + addr);
46 break;
47 case TPM_TIS_PHYS_16:
48 result[1] = ioread8(phy->iobase + addr + 1);
49 result[0] = ioread8(phy->iobase + addr);
50 break;
51 case TPM_TIS_PHYS_32:
52 result[3] = ioread8(phy->iobase + addr + 3);
53 result[2] = ioread8(phy->iobase + addr + 2);
54 result[1] = ioread8(phy->iobase + addr + 1);
55 result[0] = ioread8(phy->iobase + addr);
56 break;
57 }
58
59 return 0;
60 }
61
tpm_tis_synquacer_write_bytes(struct tpm_tis_data * data,u32 addr,u16 len,const u8 * value,enum tpm_tis_io_mode io_mode)62 static int tpm_tis_synquacer_write_bytes(struct tpm_tis_data *data, u32 addr,
63 u16 len, const u8 *value,
64 enum tpm_tis_io_mode io_mode)
65 {
66 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
67 switch (io_mode) {
68 case TPM_TIS_PHYS_8:
69 while (len--)
70 iowrite8(*value++, phy->iobase + addr);
71 break;
72 case TPM_TIS_PHYS_16:
73 return -EINVAL;
74 case TPM_TIS_PHYS_32:
75 /*
76 * Due to the limitation of SPI controller on SynQuacer,
77 * 16/32 bits access must be done in byte-wise and descending order.
78 */
79 iowrite8(value[3], phy->iobase + addr + 3);
80 iowrite8(value[2], phy->iobase + addr + 2);
81 iowrite8(value[1], phy->iobase + addr + 1);
82 iowrite8(value[0], phy->iobase + addr);
83 break;
84 }
85
86 return 0;
87 }
88
89 static const struct tpm_tis_phy_ops tpm_tcg_bw = {
90 .read_bytes = tpm_tis_synquacer_read_bytes,
91 .write_bytes = tpm_tis_synquacer_write_bytes,
92 };
93
tpm_tis_synquacer_init(struct device * dev,struct tpm_tis_synquacer_info * tpm_info)94 static int tpm_tis_synquacer_init(struct device *dev,
95 struct tpm_tis_synquacer_info *tpm_info)
96 {
97 struct tpm_tis_synquacer_phy *phy;
98
99 phy = devm_kzalloc(dev, sizeof(struct tpm_tis_synquacer_phy), GFP_KERNEL);
100 if (phy == NULL)
101 return -ENOMEM;
102
103 phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
104 if (IS_ERR(phy->iobase))
105 return PTR_ERR(phy->iobase);
106
107 return tpm_tis_core_init(dev, &phy->priv, tpm_info->irq, &tpm_tcg_bw,
108 ACPI_HANDLE(dev));
109 }
110
111 static SIMPLE_DEV_PM_OPS(tpm_tis_synquacer_pm, tpm_pm_suspend, tpm_tis_resume);
112
tpm_tis_synquacer_probe(struct platform_device * pdev)113 static int tpm_tis_synquacer_probe(struct platform_device *pdev)
114 {
115 struct tpm_tis_synquacer_info tpm_info = {};
116 struct resource *res;
117
118 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
119 if (res == NULL) {
120 dev_err(&pdev->dev, "no memory resource defined\n");
121 return -ENODEV;
122 }
123 tpm_info.res = *res;
124
125 tpm_info.irq = -1;
126
127 return tpm_tis_synquacer_init(&pdev->dev, &tpm_info);
128 }
129
tpm_tis_synquacer_remove(struct platform_device * pdev)130 static int tpm_tis_synquacer_remove(struct platform_device *pdev)
131 {
132 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
133
134 tpm_chip_unregister(chip);
135 tpm_tis_remove(chip);
136
137 return 0;
138 }
139
140 #ifdef CONFIG_OF
141 static const struct of_device_id tis_synquacer_of_platform_match[] = {
142 {.compatible = "socionext,synquacer-tpm-mmio"},
143 {},
144 };
145 MODULE_DEVICE_TABLE(of, tis_synquacer_of_platform_match);
146 #endif
147
148 #ifdef CONFIG_ACPI
149 static const struct acpi_device_id tpm_synquacer_acpi_tbl[] = {
150 { "SCX0009" },
151 {},
152 };
153 MODULE_DEVICE_TABLE(acpi, tpm_synquacer_acpi_tbl);
154 #endif
155
156 static struct platform_driver tis_synquacer_drv = {
157 .probe = tpm_tis_synquacer_probe,
158 .remove = tpm_tis_synquacer_remove,
159 .driver = {
160 .name = "tpm_tis_synquacer",
161 .pm = &tpm_tis_synquacer_pm,
162 .of_match_table = of_match_ptr(tis_synquacer_of_platform_match),
163 .acpi_match_table = ACPI_PTR(tpm_synquacer_acpi_tbl),
164 },
165 };
166
tpm_tis_synquacer_module_init(void)167 static int __init tpm_tis_synquacer_module_init(void)
168 {
169 int rc;
170
171 rc = platform_driver_register(&tis_synquacer_drv);
172 if (rc)
173 return rc;
174
175 return 0;
176 }
177
tpm_tis_synquacer_module_exit(void)178 static void __exit tpm_tis_synquacer_module_exit(void)
179 {
180 platform_driver_unregister(&tis_synquacer_drv);
181 }
182
183 module_init(tpm_tis_synquacer_module_init);
184 module_exit(tpm_tis_synquacer_module_exit);
185 MODULE_DESCRIPTION("TPM MMIO Driver for Socionext SynQuacer platform");
186 MODULE_LICENSE("GPL");
187