tpm_atmel.h

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/*
 * Copyright (C) 2005 IBM Corporation
 *
 * Authors:
 * Kylene Hall <kjhall@us.ibm.com>
 *
 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
 *
 * Device driver for TCG/TCPA TPM (trusted platform module).
 * Specifications at www.trustedcomputinggroup.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 *
 * These difference are required on power because the device must be
 * discovered through the device tree and iomap must be used to get
 * around the need for holes in the io_page_mask.  This does not happen
 * automatically because the tpm is not a normal pci device and lives
 * under the root node.
 *
 */

#ifdef CONFIG_PPC64

#include <asm/prom.h>

#define atmel_getb(chip, offset) readb(chip->vendor->iobase + offset);
#define atmel_putb(val, chip, offset) writeb(val, chip->vendor->iobase + offset)
#define atmel_request_region request_mem_region
#define atmel_release_region release_mem_region

static inline void atmel_put_base_addr(void __iomem *iobase)
{
    iounmap(iobase);
}

static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)
{
    struct device_node *dn;
    unsigned long address, size;
    const unsigned int *reg;
    int reglen;
    int naddrc;
    int nsizec;

    dn = of_find_node_by_name(NULL, "tpm");

    if (!dn)
        return NULL;

    if (!of_device_is_compatible(dn, "AT97SC3201")) {
        of_node_put(dn);
        return NULL;
    }

    reg = of_get_property(dn, "reg", &reglen);
    naddrc = of_n_addr_cells(dn);
    nsizec = of_n_size_cells(dn);

    of_node_put(dn);


    if (naddrc == 2)
        address = ((unsigned long) reg[0] << 32) | reg[1];
    else
        address = reg[0];

    if (nsizec == 2)
        size =
            ((unsigned long) reg[naddrc] << 32) | reg[naddrc + 1];
    else
        size = reg[naddrc];

    *base = address;
    *region_size = size;
    return ioremap(*base, *region_size);
}
#else
#define atmel_getb(chip, offset) inb(chip->vendor->base + offset)
#define atmel_putb(val, chip, offset) outb(val, chip->vendor->base + offset)
#define atmel_request_region request_region
#define atmel_release_region release_region
/* Atmel definitions */
enum tpm_atmel_addr {
    TPM_ATMEL_BASE_ADDR_LO = 0x08,
    TPM_ATMEL_BASE_ADDR_HI = 0x09
};

/* Verify this is a 1.1 Atmel TPM */
static int atmel_verify_tpm11(void)
{

    /* verify that it is an Atmel part */
    if (tpm_read_index(TPM_ADDR, 4) != 'A' ||
        tpm_read_index(TPM_ADDR, 5) != 'T' ||
        tpm_read_index(TPM_ADDR, 6) != 'M' ||
        tpm_read_index(TPM_ADDR, 7) != 'L')
        return 1;

    /* query chip for its version number */
    if (tpm_read_index(TPM_ADDR, 0x00) != 1 ||
        tpm_read_index(TPM_ADDR, 0x01) != 1)
        return 1;

    /* This is an atmel supported part */
    return 0;
}

static inline void atmel_put_base_addr(void __iomem *iobase)
{
}

/* Determine where to talk to device */
static void __iomem * atmel_get_base_addr(unsigned long *base, int *region_size)
{
    int lo, hi;

    if (atmel_verify_tpm11() != 0)
        return NULL;

    lo = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_LO);
    hi = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_HI);

    *base = (hi << 8) | lo;
    *region_size = 2;

    return ioport_map(*base, *region_size);
}
#endif