altos: Start work on stm32f1 support

[fw/altos] / src / stm32f1 / ao_timer.c

diff --git a/src/stm32f1/ao_timer.c b/src/stm32f1/ao_timer.c
new file mode 100644 (file)
index 0000000..116d33a
--- /dev/null
+++ b/src/stm32f1/ao_timer.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright © 2023 Keith Packard <keithp@keithp.com>
+ *
+ * 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; 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
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ao.h"
+#include <ao_task.h>
+
+#ifndef HAS_TICK
+#define HAS_TICK 1
+#endif
+
+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        val;
+
+       do {
+               before = ao_tick_count;
+               val = stm_systick.val;
+               after = ao_tick_count;
+       } while (before != after);
+
+       return (uint64_t) after * (1000000000ULL / AO_HERTZ) +
+               (uint64_t) val * (1000000000ULL / AO_SYSTICK);
+}
+
+void stm_systick_isr(void)
+{
+       if (stm_systick.ctrl & (1 << STM_SYSTICK_CTRL_COUNTFLAG)) {
+               ++ao_tick_count;
+//             ao_task_check_alarm();
+#ifdef AO_TIMER_HOOK
+               AO_TIMER_HOOK;
+#endif
+       }
+}
+
+#define SYSTICK_RELOAD (AO_SYSTICK / 100 - 1)
+
+void
+ao_timer_init(void)
+{
+       stm_systick.load = SYSTICK_RELOAD;
+       stm_systick.val = 0;
+       stm_systick.ctrl = ((1 << STM_SYSTICK_CTRL_ENABLE) |
+                           (1 << STM_SYSTICK_CTRL_TICKINT) |
+                           (STM_SYSTICK_CTRL_CLKSOURCE_HCLK_8 << STM_SYSTICK_CTRL_CLKSOURCE));
+//     stm_nvic.shpr15_12 |= (uint32_t) AO_STM_NVIC_CLOCK_PRIORITY << 24;
+}