PeerStreamer

/*

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

/**

 * @file

 * Check for AltiVec presence.

 */

#ifdef __APPLE__

#undef _POSIX_C_SOURCE

#include <sys/sysctl.h>

#elif defined(__OpenBSD__)

#include <sys/param.h>

#include <sys/sysctl.h>

#include <machine/cpu.h>

#elif defined(__AMIGAOS4__)

#include <exec/exec.h>

#include <interfaces/exec.h>

#include <proto/exec.h>

#endif /* __APPLE__ */

#include "config.h"

#include "dsputil_altivec.h"

/**

 * This function MAY rely on signal() or fork() in order to make sure AltiVec

 * is present.

 */

int mm_support(void)

{

#if HAVE_ALTIVEC

#ifdef __AMIGAOS4__

    ULONG result = 0;

    extern struct ExecIFace *IExec;

    IExec->GetCPUInfoTags(GCIT_VectorUnit, &result, TAG_DONE);

    if (result == VECTORTYPE_ALTIVEC)

        return AV_CPU_FLAG_ALTIVEC;

    return 0;

#elif defined(__APPLE__) || defined(__OpenBSD__)

#ifdef __OpenBSD__

    int sels[2] = {CTL_MACHDEP, CPU_ALTIVEC};

#else

    int sels[2] = {CTL_HW, HW_VECTORUNIT};

#endif

    int has_vu = 0;

    size_t len = sizeof(has_vu);

    int err;

    err = sysctl(sels, 2, &has_vu, &len, NULL, 0);

    if (err == 0)

        return has_vu ? AV_CPU_FLAG_ALTIVEC : 0;

    return 0;

#elif CONFIG_RUNTIME_CPUDETECT

    int proc_ver;

    // Support of mfspr PVR emulation added in Linux 2.6.17.

    __asm__ volatile("mfspr %0, 287" : "=r" (proc_ver));

    proc_ver >>= 16;

    if (proc_ver  & 0x8000 ||

        proc_ver == 0x000c ||

        proc_ver == 0x0039 || proc_ver == 0x003c ||

        proc_ver == 0x0044 || proc_ver == 0x0045 ||

        proc_ver == 0x0070)

        return AV_CPU_FLAG_ALTIVEC;

    return 0;

#else

    // Since we were compiled for AltiVec, just assume we have it

    // until someone comes up with a proper way (not involving signal hacks).

    return AV_CPU_FLAG_ALTIVEC;

#endif /* __AMIGAOS4__ */

#endif /* HAVE_ALTIVEC */

    return 0;

}