diff --git a/src-cg/libprof.c b/src-cg/libprof.c
index a0b116e..f71da75 100644
--- a/src-cg/libprof.c
+++ b/src-cg/libprof.c
@@ -1,13 +1,30 @@
 #include "libprof.h"
 
+#define CPG_FRQCRA (*(volatile uint32_t *)0xa4150000)
+#define CPG_FLLFRQ (*(volatile uint32_t *)0xa4150050)
+#define CPG_PLLCR  (*(volatile uint32_t *)0xa4150024)
+
+/* Current frequency of Pphi */
+static int Pphi;
+
 /* prof_init(): Initialize the profiler's timer */
 int prof_init(void)
 {
 	*TMU0_TCOR = 0xffffffff;
 	*TMU0_TCNT = 0xffffffff;
 	*TMU0_TCR = 0x0000; /* UNIE=0 Pphi/4 */
-
 	*TMU_TSTR |= 1;
+
+	/* Determine the Pphi frequency based on the CPG configuration */
+	int pll = CPG_PLLCR & 0x4000 /* if PLLE: STC+1 */
+		? ((CPG_FRQCRA & 0x3f000000) >> 24) + 1
+		: 1;
+	int fll = CPG_PLLCR & 0x1000 /* if FLLE: FLF >> (SELXM != 0) */
+		? (CPG_FLLFRQ & 0x07ff) >> ((CPG_FLLFRQ & 0xc000) != 0)
+		: 1;
+	/* Shift by P1FC+1 places */
+	Pphi = (32768 * fll * pll) >> ((CPG_FRQCRA & 0x0000000f) + 1);
+
 	return 0;
 }
 
@@ -20,7 +37,5 @@ void prof_quit(void)
 /* prof_time(): Time spent in a given context, in microseconds */
 uint32_t prof_time(prof_t prof)
 {
-	/* Hardcoded for the default overclock settings */
-	int Pphi = 29491200;
 	return ((uint64_t)prof.elapsed * 4 * 1000000) / Pphi;
 }