[sample] A sample program for MRS emulation

[Suzuki K Poulose]

Here is a sample program which demonstrates how to use mrs
emulation to fetch the ID registers.

----8>----
/*
 * Sample program to demonstrate the MRS emulation
 * ABI.
 * Copyright (C) 2015-2016, ARM Ltd
 *
 * Author: Suzuki K Poulose <suzuki.poul...@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <stdio.h>

#define get_cpu_ftr(id) ({                                      \
                unsigned long long __val;                       \
                asm("mrs %0, "#id : "=r" (__val));              \
                printf("%-20s: 0x%016lx\n", #id, __val);        \
        })

int main()
{

        get_cpu_ftr(ID_AA64ISAR0_EL1);
        get_cpu_ftr(ID_AA64ISAR1_EL1);
        get_cpu_ftr(ID_AA64MMFR0_EL1);
        get_cpu_ftr(ID_AA64MMFR1_EL1);
        get_cpu_ftr(ID_AA64PFR0_EL1);
        get_cpu_ftr(ID_AA64PFR1_EL1);
        get_cpu_ftr(ID_AA64DFR0_EL1);
        get_cpu_ftr(ID_AA64DFR1_EL1);

        get_cpu_ftr(MIDR_EL1);
        get_cpu_ftr(MPIDR_EL1);
        get_cpu_ftr(REVIDR_EL1);
        return 0;
}