[PATCH v2] lib/eal/ppc fix compilation for musl

[Duncan Bellamy]

musl lacks __ppc_get_timebase() but has __builtin_ppc_get_timebase()

the __ppc_get_timebase_freq() is taken from:
https://git.alpinelinux.org/aports/commit/?id=06b03f70fb94972286c0c9f6278df89e53903833

Signed-off-by: Duncan Bellamy <d...@denkimushi.com>
---
 lib/eal/ppc/include/rte_cycles.h |  6 ++++++
 lib/eal/ppc/rte_cycles.c         | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/lib/eal/ppc/include/rte_cycles.h b/lib/eal/ppc/include/rte_cycles.h
index 5585f9273c..98ffbd2592 100644
--- a/lib/eal/ppc/include/rte_cycles.h
+++ b/lib/eal/ppc/include/rte_cycles.h
@@ -10,7 +10,9 @@
 extern "C" {
 #endif
 
+#if defined(__GLIBC__)
 #include <sys/platform/ppc.h>
+#endif
 
 #include "generic/rte_cycles.h"
 
@@ -26,7 +28,11 @@ extern "C" {
 static inline uint64_t
 rte_rdtsc(void)
 {
+#if defined(__GLIBC__)
        return __ppc_get_timebase();
+#else
+       return __builtin_ppc_get_timebase();
+#endif
 }
 
 static inline uint64_t
diff --git a/lib/eal/ppc/rte_cycles.c b/lib/eal/ppc/rte_cycles.c
index 3180adb0ff..154eba722c 100644
--- a/lib/eal/ppc/rte_cycles.c
+++ b/lib/eal/ppc/rte_cycles.c
@@ -2,12 +2,44 @@
  * Copyright (C) IBM Corporation 2019.
  */
 
+#if defined(__GLIBC__)
 #include <sys/platform/ppc.h>
+#else
+#include <string.h>
+#include <stdio.h>
+#endif
 
 #include "eal_private.h"
 
 uint64_t
 get_tsc_freq_arch(void)
 {
+#if defined(__GLIBC__)
        return __ppc_get_timebase_freq();
+#else
+       static uint64_t base;
+       if (!base) {
+               FILE *f = fopen("/proc/cpuinfo", "rb");
+               if (f) {
+                       ssize_t nr;
+                       /* virtually always big enough to hold the line */
+                       char buf[512];
+                       while (fgets(buf, sizeof(buf), f)) {
+                               char *ret = strstr(buf, "timebase");
+                               if (!ret) {
+                                       continue;
+                               }
+                               ret += sizeof("timebase") - 1;
+                               ret = strchr(ret, ':');
+                               if (!ret) {
+                                       continue;
+                               }
+                               base = strtoul(ret + 1, 0, 10);
+                               break;
+                       }
+                       fclose(f);
+               }
+       }
+       return base;;
+#endif
 }
-- 
2.32.0