altos: add ao_time_ns API

[fw/altos] / src / lpc / ao_timer_lpc.c

diff --git a/src/lpc/ao_timer_lpc.c b/src/lpc/ao_timer_lpc.c
index 623559ebe14c4c69127a62c381d8a1161085a945..62b16318107f74fc354783ab8520390ac54d524b 100644 (file)
--- a/src/lpc/ao_timer_lpc.c
+++ b/src/lpc/ao_timer_lpc.c
@@ -3,7 +3,8 @@
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License.
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -17,17 +18,35 @@
 
 #include <ao.h>
 
-volatile __data AO_TICK_TYPE ao_tick_count;
+#define AO_SYSTICK     (AO_LPC_SYSCLK / 2)
 
-uint16_t
+volatile AO_TICK_TYPE ao_tick_count;
+
+AO_TICK_TYPE
 ao_time(void)
 {
        return ao_tick_count;
 }
 
+uint64_t
+ao_time_ns(void)
+{
+       AO_TICK_TYPE    before, after;
+       uint32_t        cvr;
+
+       do {
+               before = ao_tick_count;
+               cvr = lpc_systick.cvr;
+               after = ao_tick_count;
+       } while (before != after);
+
+       return (uint64_t) after * (1000000000ULL / AO_HERTZ) +
+               (uint64_t) cvr * (1000000000ULL / AO_SYSTICK);
+}
+
 #if AO_DATA_ALL
-volatile __data uint8_t        ao_data_interval = 1;
-volatile __data uint8_t        ao_data_count;
+volatile uint8_t       ao_data_interval = 1;
+volatile uint8_t       ao_data_count;
 #endif
 
 void lpc_systick_isr(void)