1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * Copyright (C) 2005 IBM Corporation |
4 | * |
5 | * Authors: |
6 | * Kylene Hall <kjhall@us.ibm.com> |
7 | * |
8 | * Maintained by: <tpmdd-devel@lists.sourceforge.net> |
9 | * |
10 | * Device driver for TCG/TCPA TPM (trusted platform module). |
11 | * Specifications at www.trustedcomputinggroup.org |
12 | * |
13 | * These difference are required on power because the device must be |
14 | * discovered through the device tree and iomap must be used to get |
15 | * around the need for holes in the io_page_mask. This does not happen |
16 | * automatically because the tpm is not a normal pci device and lives |
17 | * under the root node. |
18 | */ |
19 | |
20 | struct tpm_atmel_priv { |
21 | int region_size; |
22 | int have_region; |
23 | unsigned long base; |
24 | void __iomem *iobase; |
25 | }; |
26 | |
27 | #ifdef CONFIG_PPC64 |
28 | |
29 | #include <linux/of.h> |
30 | |
31 | #define atmel_getb(priv, offset) readb(priv->iobase + offset) |
32 | #define atmel_putb(val, priv, offset) writeb(val, priv->iobase + offset) |
33 | #define atmel_request_region request_mem_region |
34 | #define atmel_release_region release_mem_region |
35 | |
36 | static inline void atmel_put_base_addr(void __iomem *iobase) |
37 | { |
38 | iounmap(iobase); |
39 | } |
40 | |
41 | static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size) |
42 | { |
43 | struct device_node *dn; |
44 | unsigned long address, size; |
45 | const unsigned int *reg; |
46 | int reglen; |
47 | int naddrc; |
48 | int nsizec; |
49 | |
50 | dn = of_find_node_by_name(NULL, "tpm" ); |
51 | |
52 | if (!dn) |
53 | return NULL; |
54 | |
55 | if (!of_device_is_compatible(dn, "AT97SC3201" )) { |
56 | of_node_put(dn); |
57 | return NULL; |
58 | } |
59 | |
60 | reg = of_get_property(dn, "reg" , ®len); |
61 | naddrc = of_n_addr_cells(dn); |
62 | nsizec = of_n_size_cells(dn); |
63 | |
64 | of_node_put(dn); |
65 | |
66 | |
67 | if (naddrc == 2) |
68 | address = ((unsigned long) reg[0] << 32) | reg[1]; |
69 | else |
70 | address = reg[0]; |
71 | |
72 | if (nsizec == 2) |
73 | size = |
74 | ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1]; |
75 | else |
76 | size = reg[naddrc]; |
77 | |
78 | *base = address; |
79 | *region_size = size; |
80 | return ioremap(*base, *region_size); |
81 | } |
82 | #else |
83 | #define atmel_getb(chip, offset) inb(atmel_get_priv(chip)->base + offset) |
84 | #define atmel_putb(val, chip, offset) \ |
85 | outb(val, atmel_get_priv(chip)->base + offset) |
86 | #define atmel_request_region request_region |
87 | #define atmel_release_region release_region |
88 | /* Atmel definitions */ |
89 | enum tpm_atmel_addr { |
90 | TPM_ATMEL_BASE_ADDR_LO = 0x08, |
91 | TPM_ATMEL_BASE_ADDR_HI = 0x09 |
92 | }; |
93 | |
94 | static inline int tpm_read_index(int base, int index) |
95 | { |
96 | outb(value: index, port: base); |
97 | return inb(port: base+1) & 0xFF; |
98 | } |
99 | |
100 | /* Verify this is a 1.1 Atmel TPM */ |
101 | static int atmel_verify_tpm11(void) |
102 | { |
103 | |
104 | /* verify that it is an Atmel part */ |
105 | if (tpm_read_index(base: TPM_ADDR, index: 4) != 'A' || |
106 | tpm_read_index(base: TPM_ADDR, index: 5) != 'T' || |
107 | tpm_read_index(base: TPM_ADDR, index: 6) != 'M' || |
108 | tpm_read_index(base: TPM_ADDR, index: 7) != 'L') |
109 | return 1; |
110 | |
111 | /* query chip for its version number */ |
112 | if (tpm_read_index(base: TPM_ADDR, index: 0x00) != 1 || |
113 | tpm_read_index(base: TPM_ADDR, index: 0x01) != 1) |
114 | return 1; |
115 | |
116 | /* This is an atmel supported part */ |
117 | return 0; |
118 | } |
119 | |
120 | static inline void atmel_put_base_addr(void __iomem *iobase) |
121 | { |
122 | } |
123 | |
124 | /* Determine where to talk to device */ |
125 | static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size) |
126 | { |
127 | int lo, hi; |
128 | |
129 | if (atmel_verify_tpm11() != 0) |
130 | return NULL; |
131 | |
132 | lo = tpm_read_index(base: TPM_ADDR, index: TPM_ATMEL_BASE_ADDR_LO); |
133 | hi = tpm_read_index(base: TPM_ADDR, index: TPM_ATMEL_BASE_ADDR_HI); |
134 | |
135 | *base = (hi << 8) | lo; |
136 | *region_size = 2; |
137 | |
138 | return ioport_map(port: *base, nr: *region_size); |
139 | } |
140 | #endif |
141 | |