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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * Copyright (C) 2005 IBM Corporation4 *5 * Authors:6 * Kylene Hall <kjhall@us.ibm.com>7 *8 * Maintained by: <tpmdd-devel@lists.sourceforge.net>9 *10 * Device driver for TCG/TCPA TPM (trusted platform module).11 * Specifications at www.trustedcomputinggroup.org12 *13 * These difference are required on power because the device must be14 * discovered through the device tree and iomap must be used to get15 * around the need for holes in the io_page_mask. This does not happen16 * automatically because the tpm is not a normal pci device and lives17 * under the root node.18 */19 20struct tpm_atmel_priv {21 int region_size;22 int have_region;23 unsigned long base;24 void __iomem *iobase;25};26 27#ifdef CONFIG_PPC6428 29#include <linux/of.h>30 31#define atmel_getb(priv, offset) readb(priv->iobase + offset)32#define atmel_putb(val, priv, offset) writeb(val, priv->iobase + offset)33#define atmel_request_region request_mem_region34#define atmel_release_region release_mem_region35 36static inline void atmel_put_base_addr(void __iomem *iobase)37{38 iounmap(iobase);39}40 41static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)42{43 struct device_node *dn;44 unsigned long address, size;45 const unsigned int *reg;46 int reglen;47 int naddrc;48 int nsizec;49 50 dn = of_find_node_by_name(NULL, "tpm");51 52 if (!dn)53 return NULL;54 55 if (!of_device_is_compatible(dn, "AT97SC3201")) {56 of_node_put(dn);57 return NULL;58 }59 60 reg = of_get_property(dn, "reg", ®len);61 naddrc = of_n_addr_cells(dn);62 nsizec = of_n_size_cells(dn);63 64 of_node_put(dn);65 66 67 if (naddrc == 2)68 address = ((unsigned long) reg[0] << 32) | reg[1];69 else70 address = reg[0];71 72 if (nsizec == 2)73 size =74 ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1];75 else76 size = reg[naddrc];77 78 *base = address;79 *region_size = size;80 return ioremap(*base, *region_size);81}82#else83#define atmel_getb(chip, offset) inb(atmel_get_priv(chip)->base + offset)84#define atmel_putb(val, chip, offset) \85 outb(val, atmel_get_priv(chip)->base + offset)86#define atmel_request_region request_region87#define atmel_release_region release_region88/* Atmel definitions */89enum tpm_atmel_addr {90 TPM_ATMEL_BASE_ADDR_LO = 0x08,91 TPM_ATMEL_BASE_ADDR_HI = 0x0992};93 94static inline int tpm_read_index(int base, int index)95{96 outb(index, base);97 return inb(base+1) & 0xFF;98}99 100/* Verify this is a 1.1 Atmel TPM */101static int atmel_verify_tpm11(void)102{103 104 /* verify that it is an Atmel part */105 if (tpm_read_index(TPM_ADDR, 4) != 'A' ||106 tpm_read_index(TPM_ADDR, 5) != 'T' ||107 tpm_read_index(TPM_ADDR, 6) != 'M' ||108 tpm_read_index(TPM_ADDR, 7) != 'L')109 return 1;110 111 /* query chip for its version number */112 if (tpm_read_index(TPM_ADDR, 0x00) != 1 ||113 tpm_read_index(TPM_ADDR, 0x01) != 1)114 return 1;115 116 /* This is an atmel supported part */117 return 0;118}119 120static inline void atmel_put_base_addr(void __iomem *iobase)121{122}123 124/* Determine where to talk to device */125static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)126{127 int lo, hi;128 129 if (atmel_verify_tpm11() != 0)130 return NULL;131 132 lo = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_LO);133 hi = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_HI);134 135 *base = (hi << 8) | lo;136 *region_size = 2;137 138 return ioport_map(*base, *region_size);139}140#endif141