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(void __iomem *iobase)
  32 {
  33         iounmap(iobase);
  34 }
  35
  36 static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)
  37 {
  38         struct device_node *dn;
  39         unsigned long address, size;
  40         const unsigned int *reg;
  41         int reglen;
  42         int naddrc;
  43         int nsizec;
  44
  45         dn = of_find_node_by_name(NULL, "tpm");
  46
  47         if (!dn)
  48                 return NULL;
  49
  50         if (!of_device_is_compatible(dn, "AT97SC3201")) {
  51                 of_node_put(dn);
  52                 return NULL;
  53         }
  54
  55         reg = of_get_property(dn, "reg", &reglen);
  56         naddrc = of_n_addr_cells(dn);
  57         nsizec = of_n_size_cells(dn);
  58
  59         of_node_put(dn);
  60
  61
  62         if (naddrc == 2)
  63                 address = ((unsigned long) reg[0] << 32) | reg[1];
  64         else
  65                 address = reg[0];
  66
  67         if (nsizec == 2)
  68                 size =
  69                     ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1];
  70         else
  71                 size = reg[naddrc];
  72
  73         *base = address;
  74         *region_size = size;
  75         return ioremap(*base, *region_size);
  76 }
  77 #else
  78 #define atmel_getb(chip, offset) inb(chip->vendor->base + offset)
  79 #define atmel_putb(val, chip, offset) outb(val, chip->vendor->base + offset)
  80 #define atmel_request_region request_region
  81 #define atmel_release_region release_region
  82 /* Atmel definitions */
  83 enum tpm_atmel_addr {
  84         TPM_ATMEL_BASE_ADDR_LO = 0x08,
  85         TPM_ATMEL_BASE_ADDR_HI = 0x09
  86 };
  87
  88 /* Verify this is a 1.1 Atmel TPM */
  89 static int atmel_verify_tpm11(void)
  90 {
  91
  92         /* verify that it is an Atmel part */
  93         if (tpm_read_index(TPM_ADDR, 4) != 'A' ||
  94             tpm_read_index(TPM_ADDR, 5) != 'T' ||
  95             tpm_read_index(TPM_ADDR, 6) != 'M' ||
  96             tpm_read_index(TPM_ADDR, 7) != 'L')
  97                 return 1;
  98
  99         /* query chip for its version number */
 100         if (tpm_read_index(TPM_ADDR, 0x00) != 1 ||
 101             tpm_read_index(TPM_ADDR, 0x01) != 1)
 102                 return 1;
 103
 104         /* This is an atmel supported part */
 105         return 0;
 106 }
 107
 108 static inline void atmel_put_base_addr(void __iomem *iobase)
 109 {
 110 }
 111
 112 /* Determine where to talk to device */
 113 static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)
 114 {
 115         int lo, hi;
 116
 117         if (atmel_verify_tpm11() != 0)
 118                 return NULL;
 119
 120         lo = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_LO);
 121         hi = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_HI);
 122
 123         *base = (hi << 8) | lo;
 124         *region_size = 2;
 125
 126         return ioport_map(*base, *region_size);
 127 }
 128 #endif