1/*
2 * Copyright (C) 2005 IBM Corporation
3 *
4 * Authors:
5 * Kylene Hall <kjhall@us.ibm.com>
6 *
7 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
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
34static inline void atmel_put_base_addr(void __iomem *iobase)
35{
36	iounmap(iobase);
37}
38
39static 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 */
86enum tpm_atmel_addr {
87	TPM_ATMEL_BASE_ADDR_LO = 0x08,
88	TPM_ATMEL_BASE_ADDR_HI = 0x09
89};
90
91/* Verify this is a 1.1 Atmel TPM */
92static 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
111static inline void atmel_put_base_addr(void __iomem *iobase)
112{
113}
114
115/* Determine where to talk to device */
116static 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
132