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 /*

  * Copyright © 2000 SuSE, Inc.

  * Copyright © 2007 Red Hat, Inc.

  *

  * Permission to use, copy, modify, distribute, and sell this software and its

  * documentation for any purpose is hereby granted without fee, provided that

  * the above copyright notice appear in all copies and that both that

  * copyright notice and this permission notice appear in supporting

  * documentation, and that the name of SuSE not be used in advertising or

  * publicity pertaining to distribution of the software without specific,

  * written prior permission.  SuSE makes no representations about the

  * suitability of this software for any purpose.  It is provided "as is"

  * without express or implied warranty.

  *

  * SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE

  * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION

  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN

  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

  */

 #ifdef HAVE_CONFIG_H

 #include <config.h>

 #endif

 #include "pixman-private.h"

 typedef enum

 {

     ARM_V7		= (1 << 0),

     ARM_V6		= (1 << 1),

     ARM_VFP		= (1 << 2),

     ARM_NEON		= (1 << 3),

     ARM_IWMMXT		= (1 << 4)

 } arm_cpu_features_t;

 #if defined(USE_ARM_SIMD) || defined(USE_ARM_NEON) || defined(USE_ARM_IWMMXT)

 #if defined(_MSC_VER)

 /* Needed for EXCEPTION_ILLEGAL_INSTRUCTION */

 #include <windows.h>

 extern int pixman_msvc_try_arm_neon_op ();

 extern int pixman_msvc_try_arm_simd_op ();

 static arm_cpu_features_t

 detect_cpu_features (void)

 {

     arm_cpu_features_t features = 0;

     __try

     {

 	pixman_msvc_try_arm_simd_op ();

 	features |= ARM_V6;

     }

     __except (GetExceptionCode () == EXCEPTION_ILLEGAL_INSTRUCTION)

     {

     }

     __try

     {

 	pixman_msvc_try_arm_neon_op ();

 	features |= ARM_NEON;

     }

     __except (GetExceptionCode () == EXCEPTION_ILLEGAL_INSTRUCTION)

     {

     }

     return features;

 }

 #elif defined(__APPLE__) && defined(TARGET_OS_IPHONE) /* iOS */

 #include "TargetConditionals.h"

 static arm_cpu_features_t

 detect_cpu_features (void)

 {

     arm_cpu_features_t features = 0;

     features |= ARM_V6;

     /* Detection of ARM NEON on iOS is fairly simple because iOS binaries

      * contain separate executable images for each processor architecture.

      * So all we have to do is detect the armv7 architecture build. The

      * operating system automatically runs the armv7 binary for armv7 devices

      * and the armv6 binary for armv6 devices.

      */

 #if defined(__ARM_NEON__)

     features |= ARM_NEON;

 #endif

     return features;

 }

 #elif defined(__ANDROID__) || defined(ANDROID) /* Android */

 static arm_cpu_features_t

 detect_cpu_features (void)

 {

     arm_cpu_features_t features = 0;

     char buf[1024];

     char* pos;

     const char* ver_token = "CPU architecture: ";

     FILE* f = fopen("/proc/cpuinfo", "r");

     if (!f) {

 	return features;

     }

     fread(buf, sizeof(char), sizeof(buf), f);

     fclose(f);

     pos = strstr(buf, ver_token);

     if (pos) {

 	char vchar = *(pos + strlen(ver_token));

 	if (vchar >= '0' && vchar <= '9') {

 	    int ver = vchar - '0';

 	    if (ver >= 7)

 		features |= ARM_V7;

 	}

     }

     if (strstr(buf, "neon") != NULL)

 	features |= ARM_NEON;

     if (strstr(buf, "vfp") != NULL)

 	features |= ARM_VFP;

     return features;

 }

 #elif defined (__linux__) /* linux ELF */

 #include <unistd.h>

 #include <sys/types.h>

 #include <sys/stat.h>

 #include <sys/mman.h>

 #include <fcntl.h>

 #include <string.h>

 #include <elf.h>

 static arm_cpu_features_t

 detect_cpu_features (void)

 {

     arm_cpu_features_t features = 0;

     Elf32_auxv_t aux;

     int fd;

     fd = open ("/proc/self/auxv", O_RDONLY);

     if (fd >= 0)

     {

 	while (read (fd, &aux, sizeof(Elf32_auxv_t)) == sizeof(Elf32_auxv_t))

 	{

 	    if (aux.a_type == AT_HWCAP)

 	    {

 		uint32_t hwcap = aux.a_un.a_val;

 		/* hardcode these values to avoid depending on specific

 		 * versions of the hwcap header, e.g. HWCAP_NEON

 		 */

 		if ((hwcap & 64) != 0)

 		    features |= ARM_VFP;

 		if ((hwcap & 512) != 0)

 		    features |= ARM_IWMMXT;

 		/* this flag is only present on kernel 2.6.29 */

 		if ((hwcap & 4096) != 0)

 		    features |= ARM_NEON;

 	    }

 	    else if (aux.a_type == AT_PLATFORM)

 	    {

 		const char *plat = (const char*) aux.a_un.a_val;

 		if (strncmp (plat, "v7l", 3) == 0)

 		    features |= (ARM_V7 | ARM_V6);

 		else if (strncmp (plat, "v6l", 3) == 0)

 		    features |= ARM_V6;

 	    }

 	}

 	close (fd);

     }

     return features;

 }

 #else /* Unknown */

 static arm_cpu_features_t

 detect_cpu_features (void)

 {

     return 0;

 }

 #endif /* Linux elf */

 static pixman_bool_t

 have_feature (arm_cpu_features_t feature)

 {

     static pixman_bool_t initialized;

     static arm_cpu_features_t features;

     if (!initialized)

     {

 	features = detect_cpu_features();

 	initialized = TRUE;

     }

     return (features & feature) == feature;

 }

 #endif /* USE_ARM_SIMD || USE_ARM_NEON || USE_ARM_IWMMXT */

 pixman_implementation_t *

 _pixman_arm_get_implementations (pixman_implementation_t *imp)

 {

 #ifdef USE_ARM_SIMD

     if (!_pixman_disabled ("arm-simd") && have_feature (ARM_V6))

 	imp = _pixman_implementation_create_arm_simd (imp);

 #endif

 #ifdef USE_ARM_IWMMXT

     if (!_pixman_disabled ("arm-iwmmxt") && have_feature (ARM_IWMMXT))

 	imp = _pixman_implementation_create_mmx (imp);

 #endif

 #ifdef USE_ARM_NEON

     if (!_pixman_disabled ("arm-neon") && have_feature (ARM_NEON))

 	imp = _pixman_implementation_create_arm_neon (imp);

 #endif

     return imp;

 }