1 files changed, 22 insertions, 0 deletions
diff --git a/sys/arm/mv/discovery/discovery.c b/sys/arm/mv/discovery/discovery.c
index c245fa9..5d41b92 100644
--- a/sys/arm/mv/discovery/discovery.c
+++ b/sys/arm/mv/discovery/discovery.c
@@ -226,3 +226,25 @@ const struct decode_win idma_win_tbl[] = {
 };
 const struct decode_win *idma_wins = idma_win_tbl;
 int idma_wins_no = sizeof(idma_win_tbl) / sizeof(struct decode_win);
+
+uint32_t
+get_tclk(void)
+{
+	uint32_t sar;
+
+	/*
+	 * On Discovery TCLK is can be configured to 166 MHz or 200 MHz.
+	 * Current setting is read from Sample At Reset register.
+	 */
+	sar = bus_space_read_4(obio_tag, MV_MPP_BASE, SAMPLE_AT_RESET_HI);
+	sar = (sar & TCLK_MASK) >> TCLK_SHIFT;
+
+	switch (sar) {
+	case 0:
+		return (TCLK_166MHZ);
+	case 1:
+		return (TCLK_200MHZ);
+	default:
+		panic("Unknown TCLK settings!");
+	}
+}