X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2Fcc1111%2Fao_timer.c;h=2fbc6621dfdf43c9b989f5d1cbad0092b8498a9f;hb=5872bd10df14b47de0e541bff16d9220af0558aa;hp=54af9605b59bb997fa75b89508bb45e41f06e8d8;hpb=4e3955a5b0ac125bd807920c467f959618449fbc;p=fw%2Faltos

diff --git a/src/cc1111/ao_timer.c b/src/cc1111/ao_timer.c
index 54af9605..2fbc6621 100644
--- a/src/cc1111/ao_timer.c
+++ b/src/cc1111/ao_timer.c
@@ -83,18 +83,57 @@ ao_timer_init(void)
 	T1CTL = T1CTL_MODE_MODULO | T1CTL_DIV_8;
 }
 
+#ifndef NEEDS_CC1111_CLOCK_HACK
+#define NEEDS_CC1111_CLOCK_HACK		1
+#endif
+
+#if NEEDS_CC1111_CLOCK_HACK
+static void
+ao_clock_delay(void)
+{
+	uint16_t	i = 0;
+
+	while (--i)
+		ao_arch_nop();
+}
+#endif
+
 /*
  * AltOS always cranks the clock to the max frequency
  */
 void
 ao_clock_init(void)
 {
+#if NEEDS_CC1111_CLOCK_HACK
+	/* Power up both oscillators */
+	SLEEP &= ~(SLEEP_OSC_PD);
+
+	/* Switch to the HFRC oscillator */
+	CLKCON = (CLKCON & ~CLKCON_OSC_MASK) | (CLKCON_OSC_RC);
+
+	/* Wait for the HFRC oscillator to be stable */
+	while (!(SLEEP & SLEEP_HFRC_STB))
+		;
+
+	/* Delay for 'a while' waiting for the crystal to
+	 * stabilize -- the XOSC_STB bit isn't reliable
+	 *
+	 *  http://www.ti.com/lit/er/swrz022c/swrz022c.pdf
+	 */
+
+	ao_clock_delay();
+#endif
+
 	/* Switch system clock to crystal oscilator */
 	CLKCON = (CLKCON & ~CLKCON_OSC_MASK) | (CLKCON_OSC_XTAL);
 
+	/* Wait for the HFRC oscillator to be stable */
 	while (!(SLEEP & SLEEP_XOSC_STB))
 		;
 
+	/* Power down the unused HFRC oscillator */
+	SLEEP |= SLEEP_OSC_PD;
+
 	/* Crank up the timer tick and system clock speed */
 	CLKCON = ((CLKCON & ~(CLKCON_TICKSPD_MASK | CLKCON_CLKSPD_MASK)) |
 		  (CLKCON_TICKSPD_1 | CLKCON_CLKSPD_1));