drivers/char/tpm/tpm_atmel.h

   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 #define atmel_getb(chip, offset) readb(chip->vendor->iobase + offset);
  27 #define atmel_putb(val, chip, offset) writeb(val, chip->vendor->iobase + offset)
  28 #define atmel_request_region request_mem_region
  29 #define atmel_release_region release_mem_region
  30
  31 static inline void atmel_put_base_addr(struct tpm_vendor_specific
  32                                          *vendor)
  33 {
  34         iounmap(vendor->iobase);
  35 }
  36
  37 static void __iomem * atmel_get_base_addr(struct tpm_vendor_specific *vendor)
  38 {
  39         struct device_node *dn;
  40         unsigned long address, size;
  41         unsigned int *reg;
  42         int reglen;
  43         int naddrc;
  44         int nsizec;
  45
  46         dn = of_find_node_by_name(NULL, "tpm");
  47
  48         if (!dn)
  49                 return NULL;
  50
  51         if (!device_is_compatible(dn, "AT97SC3201")) {
  52                 of_node_put(dn);
  53                 return NULL;
  54         }
  55
  56         reg = (unsigned int *) get_property(dn, "reg", &reglen);
  57         naddrc = prom_n_addr_cells(dn);
  58         nsizec = prom_n_size_cells(dn);
  59
  60         of_node_put(dn);
  61
  62
  63         if (naddrc == 2)
  64                 address = ((unsigned long) reg[0] << 32) | reg[1];
  65         else
  66                 address = reg[0];
  67
  68         if (nsizec == 2)
  69                 size =
  70                     ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1];
  71         else
  72                 size = reg[naddrc];
  73
  74         vendor->base = address;
  75         vendor->region_size = size;
  76         return ioremap(vendor->base, vendor->region_size);
  77 }
  78 #else
  79 #define atmel_getb(chip, offset) inb(chip->vendor->base + offset)
  80 #define atmel_putb(val, chip, offset) outb(val, chip->vendor->base + offset)
  81 #define atmel_request_region request_region
  82 #define atmel_release_region release_region
  83 /* Atmel definitions */
  84 enum tpm_atmel_addr {
  85         TPM_ATMEL_BASE_ADDR_LO = 0x08,
  86         TPM_ATMEL_BASE_ADDR_HI = 0x09
  87 };
  88
  89 /* Verify this is a 1.1 Atmel TPM */
  90 static int atmel_verify_tpm11(void)
  91 {
  92
  93         /* verify that it is an Atmel part */
  94         if (tpm_read_index(TPM_ADDR, 4) != 'A' ||
  95             tpm_read_index(TPM_ADDR, 5) != 'T' ||
  96             tpm_read_index(TPM_ADDR, 6) != 'M' ||
  97             tpm_read_index(TPM_ADDR, 7) != 'L')
  98                 return 1;
  99
 100         /* query chip for its version number */
 101         if (tpm_read_index(TPM_ADDR, 0x00) != 1 ||
 102             tpm_read_index(TPM_ADDR, 0x01) != 1)
 103                 return 1;
 104
 105         /* This is an atmel supported part */
 106         return 0;
 107 }
 108
 109 static inline void atmel_put_base_addr(struct tpm_vendor_specific
 110                                          *vendor)
 111 {
 112 }
 113
 114 /* Determine where to talk to device */
 115 static void __iomem * atmel_get_base_addr(struct tpm_vendor_specific
 116                                          *vendor)
 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         vendor->base = (hi << 8) | lo;
 127         vendor->region_size = 2;
 128
 129         return ioport_map(vendor->base, vendor->region_size);
 130 }
 131 #endif