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 struct tpm_atmel_priv { 26 int region_size; 27 int have_region; 28 unsigned long base; 29 void __iomem *iobase; 30 }; 31 32 #ifdef CONFIG_PPC64 33 34 #include <asm/prom.h> 35 36 #define atmel_getb(priv, offset) readb(priv->iobase + offset) 37 #define atmel_putb(val, priv, offset) writeb(val, priv->iobase + offset) 38 #define atmel_request_region request_mem_region 39 #define atmel_release_region release_mem_region 40 41 static inline void atmel_put_base_addr(void __iomem *iobase) 42 { 43 iounmap(iobase); 44 } 45 46 static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size) 47 { 48 struct device_node *dn; 49 unsigned long address, size; 50 const unsigned int *reg; 51 int reglen; 52 int naddrc; 53 int nsizec; 54 55 dn = of_find_node_by_name(NULL, "tpm"); 56 57 if (!dn) 58 return NULL; 59 60 if (!of_device_is_compatible(dn, "AT97SC3201")) { 61 of_node_put(dn); 62 return NULL; 63 } 64 65 reg = of_get_property(dn, "reg", ®len); 66 naddrc = of_n_addr_cells(dn); 67 nsizec = of_n_size_cells(dn); 68 69 of_node_put(dn); 70 71 72 if (naddrc == 2) 73 address = ((unsigned long) reg[0] << 32) | reg[1]; 74 else 75 address = reg[0]; 76 77 if (nsizec == 2) 78 size = 79 ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1]; 80 else 81 size = reg[naddrc]; 82 83 *base = address; 84 *region_size = size; 85 return ioremap(*base, *region_size); 86 } 87 #else 88 #define atmel_getb(chip, offset) inb(atmel_get_priv(chip)->base + offset) 89 #define atmel_putb(val, chip, offset) \ 90 outb(val, atmel_get_priv(chip)->base + offset) 91 #define atmel_request_region request_region 92 #define atmel_release_region release_region 93 /* Atmel definitions */ 94 enum tpm_atmel_addr { 95 TPM_ATMEL_BASE_ADDR_LO = 0x08, 96 TPM_ATMEL_BASE_ADDR_HI = 0x09 97 }; 98 99 static inline int tpm_read_index(int base, int index) 100 { 101 outb(index, base); 102 return inb(base+1) & 0xFF; 103 } 104 105 /* Verify this is a 1.1 Atmel TPM */ 106 static int atmel_verify_tpm11(void) 107 { 108 109 /* verify that it is an Atmel part */ 110 if (tpm_read_index(TPM_ADDR, 4) != 'A' || 111 tpm_read_index(TPM_ADDR, 5) != 'T' || 112 tpm_read_index(TPM_ADDR, 6) != 'M' || 113 tpm_read_index(TPM_ADDR, 7) != 'L') 114 return 1; 115 116 /* query chip for its version number */ 117 if (tpm_read_index(TPM_ADDR, 0x00) != 1 || 118 tpm_read_index(TPM_ADDR, 0x01) != 1) 119 return 1; 120 121 /* This is an atmel supported part */ 122 return 0; 123 } 124 125 static inline void atmel_put_base_addr(void __iomem *iobase) 126 { 127 } 128 129 /* Determine where to talk to device */ 130 static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size) 131 { 132 int lo, hi; 133 134 if (atmel_verify_tpm11() != 0) 135 return NULL; 136 137 lo = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_LO); 138 hi = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_HI); 139 140 *base = (hi << 8) | lo; 141 *region_size = 2; 142 143 return ioport_map(*base, *region_size); 144 } 145 #endif 146