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path: root/src/via_memcpy.c
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/*
 * Copyright (C) 2004 Thomas Hellstrom, All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sub license,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE CODE SUPPLIER(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include "via_driver.h"
#include "via_memcpy.h"
#include "compiler.h"


#define BSIZ 2048 /* Size of /proc/cpuinfo buffer */
#define BSIZW 720 /* Typical Copy Width (YUV420) Copy. */
#define BSIZA 736 /* Multiple of 32 bytes */
#define BSIZH 576 /* Typical Copy Hight */

#define SSE_PREFETCH "  prefetchnta "
#define FENCE __asm__ __volatile__ ("sfence":::"memory");
#define FENCEMMS __asm__ __volatile__ ("\t"		\
				       "sfence\n\t"	\
				       "emms\n\t"	\
				       :::"memory");
#define FEMMS __asm__ __volatile__("femms":::"memory");
#define EMMS __asm__ __volatile__("emms":::"memory");

#define NOW_PREFETCH "  prefetch "


#define PREFETCH1(arch_prefetch,from)			\
    __asm__ __volatile__ (				\
			  "1:  " arch_prefetch "(%0)\n"	\
			  arch_prefetch "32(%0)\n"	\
			  arch_prefetch "64(%0)\n"	\
			  arch_prefetch "96(%0)\n"	\
			  arch_prefetch "128(%0)\n"	\
			  arch_prefetch "160(%0)\n"	\
			  arch_prefetch "192(%0)\n"	\
			  arch_prefetch "256(%0)\n"	\
			  arch_prefetch "288(%0)\n"	\
			  "2:\n"			\
			  : : "r" (from) );

#define PREFETCH2(arch_prefetch,from)			\
    __asm__ __volatile__ (				\
			  arch_prefetch "320(%0)\n"	\
			  : : "r" (from) );
#define PREFETCH3(arch_prefetch,from)			\
    __asm__ __volatile__ (				\
			  arch_prefetch "288(%0)\n"	\
			  : : "r" (from) );



#define small_memcpy(to,from,n)						\
    {									\
	__asm__ __volatile__(						\
			     "movl %2,%%ecx\n\t"			\
                             "sarl $2,%%ecx\n\t"			\
			     "rep ; movsl\n\t"				\
			     "testb $2,%b2\n\t"				\
			     "je 1f\n\t"				\
			     "movsw\n"					\
			     "1:\ttestb $1,%b2\n\t"			\
			     "je 2f\n\t"				\
			     "movsb\n"					\
			     "2:"					\
			     :"=&D" (to), "=&S" (from)			\
			     :"q" (n),"0" ((long) to),"1" ((long) from) \
			     : "%ecx","memory");			\
    }


#define SSE_CPY(prefetch,from,to,dummy,lcnt)				\
    if ((unsigned long) from & 15)			 {		\
	__asm__ __volatile__ (						\
			      "1:\n"					\
                              prefetch "320(%1)\n"			\
			      "  movups (%1), %%xmm0\n"			\
			      "  movups 16(%1), %%xmm1\n"		\
			      "  movntps %%xmm0, (%0)\n"		\
			      "  movntps %%xmm1, 16(%0)\n"		\
                              prefetch "352(%1)\n"			\
			      "  movups 32(%1), %%xmm2\n"		\
			      "  movups 48(%1), %%xmm3\n"		\
			      "  movntps %%xmm2, 32(%0)\n"		\
			      "  movntps %%xmm3, 48(%0)\n"		\
			      "  addl $64,%0\n"				\
			      "  addl $64,%1\n"				\
			      "  decl %2\n"				\
			      "  jne 1b\n"				\
			      :"=&D"(to), "=&S"(from), "=&r"(dummy)	\
			      :"0" (to), "1" (from), "2" (lcnt): "memory"); \
    } else {								\
	__asm__ __volatile__ (						\
			      "2:\n"					\
			      prefetch "320(%1)\n"			\
			      "  movaps (%1), %%xmm0\n"			\
			      "  movaps 16(%1), %%xmm1\n"		\
			      "  movntps %%xmm0, (%0)\n"		\
			      "  movntps %%xmm1, 16(%0)\n"		\
                              prefetch "352(%1)\n"			\
			      "  movaps 32(%1), %%xmm2\n"		\
			      "  movaps 48(%1), %%xmm3\n"		\
			      "  movntps %%xmm2, 32(%0)\n"		\
			      "  movntps %%xmm3, 48(%0)\n"		\
			      "  addl $64,%0\n"				\
			      "  addl $64,%1\n"				\
			      "  decl %2\n"				\
			      "  jne 2b\n"				\
			      :"=&D"(to), "=&S"(from), "=&r"(dummy)	\
			      :"0" (to), "1" (from), "2" (lcnt): "memory"); \
    }

#define MMX_CPY(prefetch,from,to,dummy,lcnt)				\
    __asm__ __volatile__ (						\
			  "1:\n"					\
			  prefetch "320(%1)\n"				\
			  "2:  movq (%1), %%mm0\n"			\
			  "  movq 8(%1), %%mm1\n"			\
			  "  movq 16(%1), %%mm2\n"			\
			  "  movq 24(%1), %%mm3\n"			\
			  "  movq %%mm0, (%0)\n"			\
			  "  movq %%mm1, 8(%0)\n"			\
			  "  movq %%mm2, 16(%0)\n"			\
			  "  movq %%mm3, 24(%0)\n"			\
			  prefetch "352(%1)\n"				\
			  "  movq 32(%1), %%mm0\n"			\
			  "  movq 40(%1), %%mm1\n"			\
			  "  movq 48(%1), %%mm2\n"			\
			  "  movq 56(%1), %%mm3\n"			\
			  "  movq %%mm0, 32(%0)\n"			\
			  "  movq %%mm1, 40(%0)\n"			\
			  "  movq %%mm2, 48(%0)\n"			\
			  "  movq %%mm3, 56(%0)\n"			\
			  "  addl $64,%0\n"				\
			  "  addl $64,%1\n"				\
			  "  decl %2\n"					\
			  "  jne 1b\n"					\
			  :"=&D"(to), "=&S"(from), "=&r"(dummy)		\
			  :"0" (to), "1" (from), "2" (lcnt) : "memory"); 

#define MMXEXT_CPY(prefetch,from,to,dummy,lcnt)				\
    __asm__ __volatile__ (						\
			  ".p2align 4,,7\n"				\
			  "1:\n"					\
			  prefetch "320(%1)\n"				\
			  "  movq (%1), %%mm0\n"			\
			  "  movq 8(%1), %%mm1\n"			\
			  "  movq 16(%1), %%mm2\n"			\
			  "  movq 24(%1), %%mm3\n"			\
			  "  movntq %%mm0, (%0)\n"			\
			  "  movntq %%mm1, 8(%0)\n"			\
			  "  movntq %%mm2, 16(%0)\n"			\
			  "  movntq %%mm3, 24(%0)\n"			\
			  prefetch "352(%1)\n"				\
			  "  movq 32(%1), %%mm0\n"			\
			  "  movq 40(%1), %%mm1\n"			\
			  "  movq 48(%1), %%mm2\n"			\
			  "  movq 56(%1), %%mm3\n"			\
			  "  movntq %%mm0, 32(%0)\n"			\
			  "  movntq %%mm1, 40(%0)\n"			\
			  "  movntq %%mm2, 48(%0)\n"			\
			  "  movntq %%mm3, 56(%0)\n"			\
			  "  addl $64,%0\n"				\
			  "  addl $64,%1\n"				\
			  "  decl %2\n"					\
			  "  jne 1b\n"					\
			  :"=&D"(to), "=&S"(from), "=&r"(dummy)		\
			  :"0" (to), "1" (from), "2" (lcnt) : "memory"); 


#define PREFETCH_FUNC(prefix,itype,ptype,begin,fence)			\
									\
    static void prefix##_YUV42X(unsigned char *to,			\
				const unsigned char *from,		\
				int dstPitch,				\
				int w,					\
				int h,					\
				int yuv422)				\
     									\
    {									\
	int								\
	    dadd,rest,count,hc,lcnt;					\
	register int dummy;						\
	PREFETCH1(ptype##_PREFETCH,from);				\
	begin;								\
	count = 2;							\
									\
	/*								\
	 * If destination pitch and width ar equal, do it all in one go. \
	 */								\
									\
	if ( yuv422 ) {							\
	    w <<= 1;							\
	    if (w == dstPitch) {					\
		w *= h;							\
		h = 1;							\
		dstPitch = w;						\
		count = 0;						\
	    } else {							\
		h -= 1;							\
		count = 1;						\
	    }								\
	} else if (w == dstPitch) {					\
	    w = h*(w + (w >> 1));					\
	    count = 0;							\
	    h = 1;							\
	    dstPitch = w;						\
	}								\
									\
	lcnt = w >> 6;							\
	rest = w & 63;							\
	while(count--) {						\
	    hc = h;							\
	    lcnt = w >> 6;						\
	    rest = w & 63;						\
	    dadd = dstPitch - w;					\
	    while(hc--) {						\
		if (lcnt) {						\
		    itype##_CPY(ptype##_PREFETCH,from,to,dummy,		\
				lcnt);					\
		}							\
		if (rest) {						\
		    PREFETCH2(ptype##_PREFETCH,from);			\
		    small_memcpy(to, from, rest);			\
		    PREFETCH3(ptype##_PREFETCH,from);			\
		}							\
		to += dadd;						\
	    }								\
	    w >>= 1;							\
	    dstPitch >>= 1;						\
	    h -= 1;							\
	}								\
	if (lcnt > 5) {							\
	    lcnt -= 5;							\
	    itype##_CPY(ptype##_PREFETCH,from,to,dummy,lcnt);		\
	    lcnt = 5;							\
	}								\
	if (lcnt) {							\
	    itype##_CPY("#",from,to,dummy,lcnt);			\
	}								\
	if (rest) small_memcpy(to, from, rest);				\
	fence;								\
    }

#define NOPREFETCH_FUNC(prefix,itype,begin,fence)			\
    static void prefix##_YUV42X(unsigned char *to,			\
				const unsigned char *from,		\
				int dstPitch,				\
				int w,					\
				int h,					\
				int yuv422)				\
						\
    {						\
	int					\
	    dadd,rest,count,hc,lcnt;		\
	register int dummy;			\
	begin;					\
	count = 2;				\
						\
	/*								\
	 * If destination pitch and width ar equal, do it all in one go. \
	 */								\
									\
	if ( yuv422 ) {							\
	    w <<= 1;							\
	    count = 1;							\
	    if (w == dstPitch) {					\
		w *= h;							\
		h = 1;							\
		dstPitch = w;						\
	    }								\
	} else if (w == dstPitch) {					\
	    w = h*(w + (w >> 1));					\
	    count = 1;							\
	    h = 1;							\
	    dstPitch = w;						\
	}								\
									\
	lcnt = w >> 6;							\
	rest = w & 63;							\
	while(count--) {						\
	    hc = h;							\
	    dadd = dstPitch - w;					\
	    lcnt = w >> 6;						\
	    rest = w & 63;						\
	    while(hc--) {						\
		if (lcnt) {						\
		    itype##_CPY("#",from,to,dummy,lcnt);		\
		}							\
		if (rest) small_memcpy(to, from, rest);			\
		to += dadd;						\
	    }								\
	    w >>= 1;							\
	    dstPitch >>= 1;						\
	}								\
	fence;								\
    }									\

#if !defined(__i386__) || (defined(linux) && defined(__i386__)) 

static void libc_YUV42X(unsigned char *dst,
			const unsigned char *src,
			int dstPitch,
			int w,
			int h, int yuv422) {
    if ( yuv422 ) w <<= 1;
    if (dstPitch == w) {
	int size = h*((yuv422) ? w : (w + (w >> 1)));
	xf86memcpy(dst, src, size);
	return;
    } else {
	int count;

	/* copy Y component to video memory */

	count = h;
	while(count--) {
	    xf86memcpy(dst, src, w);
	    src += w;
	    dst += dstPitch;
	}
	
	/* UV component is 1/2 of Y */

	if (! yuv422 ) {

	    w >>= 1;
	    dstPitch >>= 1;
	    
	    /* copy V(Cr),U(Cb) components to video memory */

	    count = h;
	    while(count--) {
		xf86memcpy(dst, src, w);
		src += w;
		dst += dstPitch;
	    }
	}
    }
}
#endif

#ifdef __i386__



/* linux kernel __memcpy */
static __inline void * __memcpy(void * to, const void * from, size_t n)
{
    int d1,d2,d3;

    __asm__ __volatile__(
			 "rep ; movsl\n\t"
			 "testb $2,%b4\n\t"
			 "je 1f\n\t"
			 "movsw\n"
			 "1:\ttestb $1,%b4\n\t"
			 "je 2f\n\t"
			 "movsb\n"
			 "2:"
			 : "=&c" (d1), "=&D" (d2), "=&S" (d3)	
			 :"0" (n >> 2), "q" (n),"1" ((long) to),"2" ((long) from)
			 : "memory");
  
    return (to);
}


static void kernel_YUV42X(unsigned char *dst,
			  const unsigned char *src,
			  int dstPitch,
			  int w,
			  int h, int yuv422) {

    if ( yuv422 ) w <<= 1;
    if (dstPitch == w) {
	int size = h*((yuv422) ? w : (w + (w >> 1)));
	__memcpy(dst, src, size);
	return;
    } else {
	int count;

	/* copy Y component to video memory */

	count = h;
	while(count--) {
	    __memcpy(dst, src, w);
	    src += w;
	    dst += dstPitch;
	}
	
	/* UV component is 1/2 of Y */

	if (! yuv422 ) {

	    w >>= 1;
	    dstPitch >>= 1;
	    
	    /* copy V(Cr),U(Cb) components to video memory */

	    count = h;
	    while(count--) {
		__memcpy(dst, src, w);
		src += w;
		dst += dstPitch;
	    }
	}
    }
}

#ifdef linux

PREFETCH_FUNC(sse,SSE,SSE,,FENCE) 
PREFETCH_FUNC(mmxext,MMXEXT,SSE,EMMS,FENCEMMS)
PREFETCH_FUNC(now,MMX,NOW,FEMMS,FEMMS)
NOPREFETCH_FUNC(mmx,MMX,EMMS,EMMS)


static void * kernel_memcpy(void * to, const void * from, size_t len) {
    return __memcpy(to, from, len);
}

static unsigned fastrdtsc(void)
{
    unsigned eax;
    __asm__ volatile ("\t"
		      "cpuid\n\t"
		      ".byte 0x0f, 0x31" 
		      : "=a" (eax)
		      : "0"(0)
		      : "ebx","ecx","edx","cc");     
    return eax; 
}



static unsigned time_function(vidCopyFunc mf,unsigned char *buf1, 
			      unsigned char *buf2) {
    unsigned t,t2;

    t = fastrdtsc();

    (*mf)(buf1,buf2,BSIZA,BSIZW,BSIZH,0);

    t2 = fastrdtsc(); 
    return ((t <  t2) ? t2 - t : 0xFFFFFFFFU - (t - t2 -1)); 
}

enum {libc=0,kernel,sse,mmx,now,mmxext,totNum};


typedef struct {
    vidCopyFunc mFunc;
    char *mName,**cpuFlag;
} McFuncData;

char *libc_cpuflags[] = {" ",0};
char *kernel_cpuflags[] = {" ",0};
char *sse_cpuflags[] = {" sse ",0};
char *mmx_cpuflags[] = {" mmx ",0};
char *now_cpuflags[] = {" 3dnow ",0};
char *mmx2_cpuflags[] = {" mmxext ", " sse ",0};

static McFuncData mcFunctions[totNum] = 
    {{libc_YUV42X,"libc",libc_cpuflags},
     {kernel_YUV42X,"kernel",kernel_cpuflags}, 
     {sse_YUV42X,"SSE",sse_cpuflags}, 
     {mmx_YUV42X,"MMX",mmx_cpuflags}, 
     {now_YUV42X,"3DNow!",now_cpuflags}, 
     {mmxext_YUV42X,"MMX2",mmx2_cpuflags}}; 


static int flagValid(const char *cpuinfo, char *flag) {

    const char *flagLoc,*nextProc;
    int located = 0;

    while ((cpuinfo = strstr(cpuinfo, "processor\t:"))) {
        located = 1;
        cpuinfo += 11;
	if ((flagLoc = strstr(cpuinfo,flag))) {
	    if ((nextProc = strstr(cpuinfo,"processor\t:"))) {
	        if (nextProc < flagLoc) return 0;
	    }
	} else {
	    return 0;
	}
    }
    return located;
}
      

static int cpuValid(const char *cpuinfo, char **flags) {


    for(; *flags != 0; flags++) {
        if (flagValid(cpuinfo, *flags)) return 1;
    }
    return 0;
}
#endif 


vidCopyFunc viaVidCopyInit( char *copyType, 
			    ScreenPtr pScreen ) {

    /*
     * Benchmark the video copy routines using a relevant benchmark
     * and choose the fastest.
     */ 

    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];  
#ifdef linux
    char buf[BSIZ];
    unsigned char *buf1,*buf2,*buf3;
    char *tmpBuf,*endBuf;
    int count,j,bestSoFar;
    unsigned best,tmp,testSize,alignSize,tmp2;
    VIAMem tmpFbBuffer;
    McFuncData *curData;
    FILE *cpuInfoFile;
    double cpuFreq;
    VIAPtr pVia = VIAPTR(pScrn);

    pScrn->pScreen = pScreen;
    if (NULL == (cpuInfoFile = fopen("/proc/cpuinfo","r"))) {
	return libc_YUV42X;
    }
    count = fread(buf,1,BSIZ,cpuInfoFile);
    if (ferror(cpuInfoFile)) {
	fclose(cpuInfoFile);
	return libc_YUV42X;
    }
    fclose(cpuInfoFile);
    if (BSIZ == count) {
	xf86DrvMsg(pScrn->scrnIndex, X_WARNING,
		   "\"/proc/cpuinfo\" file too long. "
		   "Using Linux kernel memcpy.\n");
	return libc_YUV42X;
    }
    buf[count] = 0;

    while(count--) 
	if ('\n' == buf[count]) buf[count] = ' '; 
    
    /*
     * Extract the cpu frequency.
     */ 
    
    cpuFreq = 0.;

    if (NULL != (tmpBuf = strstr(buf,"cpu MHz"))) {
	if (NULL != (tmpBuf = strstr(tmpBuf,":") + 1)) {
	    cpuFreq = strtod(tmpBuf,&endBuf);
	    if (endBuf == tmpBuf) tmpBuf = NULL;
	}
    }
	
    alignSize = BSIZH*(BSIZA + (BSIZA >> 1));
    testSize = BSIZH*(BSIZW + (BSIZW >> 1));
    tmpFbBuffer.pool = 0;

    /*
     * Allocate an area of offscreen FB memory, (buf1), a simulated video
     * player buffer (buf2) and a pool of uninitialized "video" data (buf3). 
     */ 

    if (VIAAllocLinear(&tmpFbBuffer, pScrn, alignSize + 31))
	return libc_YUV42X;
    if (NULL == (buf2 = (unsigned char *)xalloc(testSize))) {
	VIAFreeLinear(&tmpFbBuffer);
	return libc_YUV42X;
    }
    if (NULL == (buf3 = (unsigned char *)xalloc(testSize))) {
	xfree(buf2);
	VIAFreeLinear(&tmpFbBuffer);
	return libc_YUV42X;
    }
    buf1 = (unsigned char *)pVia->FBBase + tmpFbBuffer.base;

    /*
     * Align the frame buffer destination memory to a 32 byte boundary.
     */

    if ((unsigned long)buf1 & 31) 
	buf1 += (32 - ((unsigned long)buf1 & 31));
      
    bestSoFar = 0;
    best = 0xFFFFFFFFU;
  
    /*
     * Make probable buf1 and buf2 are not paged out by
     * referencing them.
     */ 

    libc_YUV42X(buf1,buf2,BSIZA,BSIZW,BSIZH,0);


    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
	       "Benchmarking %s copy. Less is better.\n",copyType);
    for (j=0; j<totNum; ++j) {
	curData = mcFunctions + j;   

	if (cpuValid(buf,curData->cpuFlag)) {

	    /*
	     * Simulate setup of the video buffer.
	     */ 

	    kernel_memcpy(buf2,buf3,testSize);

	    /*
	     * Copy the video buffer to frame-buffer memory.
	     */

	    tmp = time_function(curData->mFunc,buf1,buf2);

	    /*
	     * Do it again to avoid context switch effects.
	     */

	    kernel_memcpy(buf2,buf3,testSize);
	    tmp2 = time_function(curData->mFunc,buf1,buf2);
	    tmp = (tmp2 < tmp) ? tmp2 : tmp;

	    if (NULL == tmpBuf) {
		xf86DrvMsg(pScrn->scrnIndex, X_PROBED,
			   "Timed %6s YUV420 copy... %u.\n",curData->mName,tmp);
	    } else {
		xf86DrvMsg(pScrn->scrnIndex, X_PROBED,
			   "Timed %6s YUV420 copy... %u. "
			   "Throughput: %.1f MiB/s.\n",curData->mName,tmp,
			   cpuFreq * 1.e6 * (double)testSize / 
			   ((double)(tmp) * (double)(0x100000)));
	    }		
	    if (tmp < best) {
		best = tmp;
		bestSoFar = j;
	    }
	} else {
	    xf86DrvMsg(pScrn->scrnIndex, X_PROBED,
		       "Ditch %6s YUV420 copy... Not supported by CPU.\n",
		       curData->mName);

	} 
    }
    xfree(buf3);
    xfree(buf2);
    VIAFreeLinear(&tmpFbBuffer);
    xf86DrvMsg(pScrn->scrnIndex, X_PROBED,
	       "Using %s YUV42X copy for %s.\n",mcFunctions[bestSoFar].mName,
	       copyType);
    return mcFunctions[bestSoFar].mFunc;
#endif
    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
	       "Using copy of Linux kernel memcpy for video.\n");
    return kernel_YUV42X;
}

#else
 
vidCopyFunc viaVidCopyInit( char *copyType, 
			    ScreenPtr pScreen ) {
    ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];  
    xf86DrvMsg(pScrn->scrnIndex, X_INFO,
	       "Using default xfree86 memcpy for video.\n");
    return libc_YUV42X;
}

#endif