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