vdr/ac3dec/cpu_accel.c

/*****
*
* This file is part of the OMS program.
*
* 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; either version 2, or (at your option)
* any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING.  If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*****/

#include <inttypes.h>
#include "mm_accel.h"

//#ifdef __i386__
#if 0

#ifdef __PIC__
#define cpuid(op, eax, ebx, ecx, edx)		\
	__asm__ __volatile__ ("pushl %%ebx\n\t"	\
		  "cpuid\n\t"			\
		  "movl %%ebx, %%esi\n\t"	\
		  "popl %%ebx"			\
		: "=a" (eax),			\
		  "=S" (ebx),			\
		  "=c" (ecx),			\
		  "=d" (edx)			\
		: "a" (op)			\
		: "cc")
#else
#define cpuid(op, eax, ebx, ecx, edx)		\
	__asm__("cpuid"				\
		: "=a" (eax),			\
		  "=b" (ebx),			\
		  "=c" (ecx),			\
		  "=d" (edx)			\
		: "a" (op)			\
		: "cc")
#endif

static inline int has_cpuid ()
{
	return 1;
/*
	uint32_t eax, ebx;

	asm ("pushfl\n\t"
		  "popl %0\n\t"
		  "movl %0,%1\n\t"
		  "xorl $0x200000,%0\n\t"
		  "pushl %0\n\t"
		  "popfl\n\t"
		  "pushfl\n\t"
		  "popl %0"
		: "=a" (eax),
		  "=b" (ebx)
		:
		: "cc");

	return (eax != ebx);
*/
}


static uint32_t x86_accel (void)
{
	uint32_t eax, ebx, ecx, edx;
	int AMD;
	uint32_t caps;

	if (!has_cpuid ())		// no cpuid
		return 0;

	cpuid (0x00000000, eax, ebx, ecx, edx);
	if (!eax)			// vendor string only
		return 0;

	AMD = (ebx == 0x68747541) && (ecx == 0x444d4163) && (edx == 0x69746e65);

	cpuid (0x00000001, eax, ebx, ecx, edx);
	if (! (edx & 0x00800000))	// no MMX
		return 0;

	caps = OMS_ACCEL_X86_MMX;
	if (edx & 0x02000000)		// SSE - identical to AMD MMX extensions
		caps = OMS_ACCEL_X86_MMX | OMS_ACCEL_X86_MMXEXT;

	cpuid (0x80000000, eax, ebx, ecx, edx);
	if (eax < 0x80000001)		// no extended capabilities
		return caps;

	cpuid (0x80000001, eax, ebx, ecx, edx);

	if (edx & 0x80000000)
		caps |= OMS_ACCEL_X86_3DNOW;

	if (AMD && (edx & 0x00400000))	// AMD MMX extensions
		caps |= OMS_ACCEL_X86_MMXEXT;

	return caps;
}
#endif

uint32_t mm_accel (void)
{
//#ifdef __i386__
#if 0
    static int got_accel = 0;
    static uint32_t accel;

    if (!got_accel) {
	got_accel = 1;
	accel = x86_accel ();
    }

    return accel;
#else
    return 0;
#endif
}