[Pixman] [PATCH 7/8] MIPS: runtime detection extended

[Nemanja Lukic]

This patch extend runtime detection in way that for kernel version
newer than 3.7, searches for strings in added fields to file
/proc/cpuinfo: "isa" and "ASEs implemented". Check for the exact MIPS
core types is used for older kernel versions.
---
 pixman/pixman-mips.c |   46 +++++++++++++++++++++++++++++++++++++---------
 1 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/pixman/pixman-mips.c b/pixman/pixman-mips.c
index eadf912..53c1023 100644
--- a/pixman/pixman-mips.c
+++ b/pixman/pixman-mips.c
@@ -53,7 +53,7 @@ static const char *mips_loongson_cores[] = {"Loongson", NULL};
     defined(USE_MIPS32R2) || defined(USE_LOONGSON_MMI)
 
 static pixman_bool_t
-have_feature (const char **cores)
+have_feature (const char **cores, const char *search_string)
 {
 #if defined (__linux__) /* linux ELF */
     /* Simple detection of MIPS features at runtime for Linux.
@@ -62,18 +62,46 @@ have_feature (const char **cores)
      * facility is universally available on the MIPS architectures, so it's up
      * to individual OSes to provide such.
      */
-    const char *file_name = "/proc/cpuinfo";
-    char cpuinfo_line[256];
+    const char *file_name = "/proc/version";
+    char line[256];
+    int v0 = 0, v1 = 0;
     FILE *f = NULL;
 
+    if ((f = fopen (file_name, "r")) != NULL)
+    {
+        if (fgets (line, sizeof (line), f) != NULL)
+        {
+            sscanf (line, "%*s%*s%d%*c%d", &v0, &v1);
+        }
+        fclose (f);
+    }
+
+    file_name = "/proc/cpuinfo";
+
     if ((f = fopen (file_name, "r")) == NULL)
         return FALSE;
 
+    if ((v0 >= 3) && (v1 >= 7))
+    {
+        /* isa filed (mips32r2) is available from kernel version 3.9
+         * ASEs implemented field (dsp, dsp2) is available from 3.7
+         */
+        while (fgets (line, sizeof (line), f) != NULL)
+        {
+            if (strstr (line, search_string) != NULL)
+            {
+                fclose (f);
+                return TRUE;
+            }
+        }
+        rewind(f);
+    }
+
     while (*cores)
     {
-        while (fgets (cpuinfo_line, sizeof (cpuinfo_line), f) != NULL)
+        while (fgets (line, sizeof (line), f) != NULL)
         {
-            if (strstr (cpuinfo_line, *cores) != NULL)
+            if (strstr (line, *cores) != NULL)
             {
                 fclose (f);
                 return TRUE;
@@ -100,7 +128,7 @@ _pixman_mips_get_implementations (pixman_implementation_t *imp)
 #ifdef USE_LOONGSON_MMI
     /* I really don't know if some Loongson CPUs don't have MMI. */
     if (!_pixman_disabled ("loongson-mmi") &&
-        have_feature (mips_loongson_cores))
+        have_feature (mips_loongson_cores, "Loongson"))
 	imp = _pixman_implementation_create_mmx (imp);
 #endif
 
@@ -117,7 +145,7 @@ _pixman_mips_get_implementations (pixman_implementation_t *imp)
         already_compiling_everything_for_mips32r2 = 1;
 #endif
         if (already_compiling_everything_for_mips32r2 ||
-            have_feature (mips32r2_cores))
+            have_feature (mips32r2_cores, " mips32r2"))
         {
             imp = _pixman_implementation_create_mips32r2 (imp);
         }
@@ -132,7 +160,7 @@ _pixman_mips_get_implementations (pixman_implementation_t *imp)
         already_compiling_everything_for_dspr1 = 1;
 #endif
         if (already_compiling_everything_for_dspr1 ||
-            have_feature (mips_dspr1_cores))
+            have_feature (mips_dspr1_cores, " dsp"))
         {
             imp = _pixman_implementation_create_mips_dspr1 (imp);
         }
@@ -147,7 +175,7 @@ _pixman_mips_get_implementations (pixman_implementation_t *imp)
 	already_compiling_everything_for_dspr2 = 1;
 #endif
 	if (already_compiling_everything_for_dspr2 ||
-	    have_feature (mips_dspr2_cores))
+	    have_feature (mips_dspr2_cores, " dsp2"))
 	{
 	    imp = _pixman_implementation_create_mips_dspr2 (imp);
 	}
-- 
1.7.3