From b2b18de0ec69c96d4500daf4db95ecebde410e12 Mon Sep 17 00:00:00 2001
From: Mark Pizzolato <mark@infocomm.com>
Date: Thu, 3 Aug 2017 18:51:55 -0700
Subject: [PATCH] TIMER: Use standard calibration techniques while throttling

Part of a previous change introduced logice which used the throttling
execution rate calibrated value to determine clock calibration when
throttling is enabled.  This provides significantly worse results than the
normal self correcting calibration process.  This commit reverses that
part of the previous change.
---
 sim_timer.c | 29 ++++++-----------------------
 1 file changed, 6 insertions(+), 23 deletions(-)

diff --git a/sim_timer.c b/sim_timer.c
index 19d35f77..25298a41 100644
--- a/sim_timer.c
+++ b/sim_timer.c
@@ -888,10 +888,7 @@ if (rtc_hz[tmr] != ticksper) {                          /* changing tick rate? *
     _rtcn_configure_calibrated_clock (tmr);
     if (ticksper != 0) {
         rtc_clock_tick_size[tmr] = 1.0 / ticksper;
-        if (sim_throt_type != SIM_THROT_NONE)
-            rtc_currd[tmr] = (int32)(sim_throt_cps / ticksper);
-        else
-            rtc_currd[tmr] = (int32)(sim_timer_inst_per_sec () / ticksper);
+        rtc_currd[tmr] = (int32)(sim_timer_inst_per_sec () / ticksper);
         }
     }
 if (ticksper == 0)                                      /* running? */
@@ -909,18 +906,11 @@ if (rtc_ticks[tmr] < ticksper)                          /* 1 sec yet? */
     return rtc_currd[tmr];
 rtc_ticks[tmr] = 0;                                     /* reset ticks */
 rtc_elapsed[tmr] = rtc_elapsed[tmr] + 1;                /* count sec */
-if (sim_throt_type != SIM_THROT_NONE) {
-    rtc_gtime[tmr] = sim_gtime();                       /* save instruction time */
-    rtc_currd[tmr] = (int32)(sim_throt_cps / ticksper); /* use throttle calibration */
-    ++rtc_calibrations[tmr];                            /* count calibrations */
-    sim_debug (DBG_CAL, &sim_timer_dev, "using throttle calibrated value - result: %d\n", rtc_currd[tmr]);
-    return rtc_currd[tmr];
-    }
 if (!rtc_avail)                                         /* no timer? */
     return rtc_currd[tmr];
 if (sim_calb_tmr != tmr) {
     rtc_currd[tmr] = (int32)(sim_timer_inst_per_sec()/ticksper);
-    sim_debug (DBG_CAL, &sim_timer_dev, "calibrated calibrated tmr=%d against system tmr=%d, tickper=%d (result: %d)\n", tmr, sim_calb_tmr, ticksper, rtc_currd[tmr]);
+    sim_debug (DBG_CAL, &sim_timer_dev, "calibrated calibrated tmr=%d against internal system tmr=%d, tickper=%d (result: %d)\n", tmr, sim_calb_tmr, ticksper, rtc_currd[tmr]);
     return rtc_currd[tmr];
     }
 new_rtime = sim_os_msec ();                             /* wall time */
@@ -1396,16 +1386,13 @@ DEVICE sim_timer_dev = {
     SIM_NTIMERS+1, 0, 0, 0, 0, 0, 
     NULL, NULL, &sim_timer_clock_reset, NULL, NULL, NULL, 
     NULL, DEV_DEBUG | DEV_NOSAVE, 0, 
-    sim_timer_debug, NULL, NULL, NULL, NULL, NULL,
-    sim_timer_description};
+    sim_timer_debug};
 
 DEVICE sim_int_timer_dev = {
     "INT-TIMER", &sim_internal_timer_unit, NULL, NULL, 
     1, 0, 0, 0, 0, 0, 
     NULL, NULL, NULL, NULL, NULL, NULL, 
-    NULL, DEV_NOSAVE, 0,
-    NULL, NULL, NULL, NULL, NULL, NULL,
-    sim_int_timer_description};
+    NULL, DEV_NOSAVE};
 
 DEVICE sim_stop_dev = {
     "INT-STOP", &sim_stop_unit, NULL, NULL, 
@@ -1416,12 +1403,7 @@ DEVICE sim_stop_dev = {
     sim_int_stop_description};
 
 DEVICE sim_throttle_dev = {
-    "INT-THROTTLE", &sim_throttle_unit, sim_throttle_reg, NULL, 1,
-    0, 0, 0, 0, 0, 
-    NULL, NULL, NULL, NULL, NULL, NULL, 
-    NULL, 0, 0, 
-    NULL, NULL, NULL, NULL, NULL, NULL,
-    sim_throttle_description};
+    "INT-THROTTLE", &sim_throttle_unit, sim_throttle_reg, NULL, 1};
 
 
 /* SET CLOCK command */
@@ -2257,6 +2239,7 @@ _rtcn_configure_calibrated_clock (sim_calb_tmr);
 sim_timer_dev.description = &sim_timer_description;
 sim_throttle_dev.description = &sim_throttle_description;
 sim_int_timer_dev.description = &sim_int_timer_description;
+sim_stop_dev.description = &sim_int_stop_description;
 if (sim_switches & SWMASK ('P')) {
     sim_cancel (&SIM_INTERNAL_UNIT);
     sim_calb_tmr = -1;