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
  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 */
  86 enum 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 */
  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