From 1bc770c3dc308b91184e8cab52f6f4cabdda99fc Mon Sep 17 00:00:00 2001
From: Jeff Epler <jepler@gmail.com>
Date: Tue, 17 Nov 2020 17:31:54 -0600
Subject: esp32s2: PulseIn: Fix supervisor tick enabling

Before, there were two problems:
 * Even if a pulsein was never constructed, supervisor_disable_tick
   would occur during restart.  This could cancel out a supervisor_enable_tick
   from someplace else, with unexpected results.
 * If two or more pulseins were constructed, each one would enable ticks,
   but only the last one deinited (or the reset routine) would disable,
   leaving ticks running indefinitely.

In my testing, it seemed that this led to the board sometimes stopping when
it should have auto-reloaded.
---
 ports/esp32s2/common-hal/pulseio/PulseIn.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/ports/esp32s2/common-hal/pulseio/PulseIn.c b/ports/esp32s2/common-hal/pulseio/PulseIn.c
index f7429ec12..9feeea147 100644
--- a/ports/esp32s2/common-hal/pulseio/PulseIn.c
+++ b/ports/esp32s2/common-hal/pulseio/PulseIn.c
@@ -77,7 +77,9 @@ void pulsein_reset(void) {
     for (size_t i = 0; i < RMT_CHANNEL_MAX; i++) {
         handles[i] = NULL;
     }
-    supervisor_disable_tick();
+    if (refcount != 0) {
+        supervisor_disable_tick();
+    }
     refcount = 0;
 }
 
@@ -122,8 +124,10 @@ void common_hal_pulseio_pulsein_construct(pulseio_pulsein_obj_t* self, const mcu
 
     // start RMT RX, and enable ticks so the core doesn't turn off.
     rmt_rx_start(channel, true);
-    supervisor_enable_tick();
     refcount++;
+    if (refcount == 1) {
+        supervisor_enable_tick();
+    }
 }
 
 bool common_hal_pulseio_pulsein_deinited(pulseio_pulsein_obj_t* self) {
-- 
cgit v1.2.3


From 9206925bf8d2e3d8220b59200ee50c3e4c8a64d2 Mon Sep 17 00:00:00 2001
From: Jeff Epler <jepler@gmail.com>
Date: Tue, 17 Nov 2020 17:45:12 -0600
Subject: esp32s2: port_get_raw_ticks: Use a more efficient, monotonic routine

While trying to debug #3572, I noticed that I would frequently break in
the midst of gettimeofday and that the routine get_adjusted_boot_time
had to take and release locks.  Furthermore, we don't want "adjusted"
boot time, which could go forwards or backwards depending on the
adjustment (such as setting the clock used by gettimeofday() to the network
time)
---
 ports/esp32s2/supervisor/port.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/ports/esp32s2/supervisor/port.c b/ports/esp32s2/supervisor/port.c
index 47d0c7f46..876ad739d 100644
--- a/ports/esp32s2/supervisor/port.c
+++ b/ports/esp32s2/supervisor/port.c
@@ -191,14 +191,14 @@ uint32_t port_get_saved_word(void) {
 }
 
 uint64_t port_get_raw_ticks(uint8_t* subticks) {
-    struct timeval tv_now;
-    gettimeofday(&tv_now, NULL);
-    // convert usec back to ticks
-    uint64_t all_subticks = (uint64_t)(tv_now.tv_usec * 2) / 71;
+    // Convert microseconds to subticks of 1/32768 seconds
+    // 32768/1000000 = 64/15625 in lowest terms
+    // this arithmetic overflows after 570 years
+    int64_t all_subticks = esp_timer_get_time() * 512 / 15625;
     if (subticks != NULL) {
         *subticks = all_subticks % 32;
     }
-    return (uint64_t)tv_now.tv_sec * 1024L + all_subticks / 32;
+    return all_subticks / 32;
 }
 
 // Enable 1/1024 second tick.
-- 
cgit v1.2.3