[src/trunk]: src/sys/arch/arm/cortex Fix some bugs.

[matt <matt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c4ada7fdda08
branches:  trunk
changeset: 789756:c4ada7fdda08
user:      matt <matt%NetBSD.org@localhost>
date:      Sat Sep 07 01:42:44 2013 +0000

description:
Fix some bugs.

diffstat:

 sys/arch/arm/cortex/gtmr.c |  71 +++++++++++++++++++++++++++++----------------
 1 files changed, 46 insertions(+), 25 deletions(-)

diffs (126 lines):

diff -r b915601790fe -r c4ada7fdda08 sys/arch/arm/cortex/gtmr.c
--- a/sys/arch/arm/cortex/gtmr.c        Sat Sep 07 00:35:52 2013 +0000
+++ b/sys/arch/arm/cortex/gtmr.c        Sat Sep 07 01:42:44 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: gtmr.c,v 1.2 2013/06/20 05:30:21 matt Exp $    */
+/*     $NetBSD: gtmr.c,v 1.3 2013/09/07 01:42:44 matt Exp $    */
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: gtmr.c,v 1.2 2013/06/20 05:30:21 matt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: gtmr.c,v 1.3 2013/09/07 01:42:44 matt Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -128,37 +128,50 @@
 gtmr_init_cpu_clock(struct cpu_info *ci)
 {
        struct gtmr_softc * const sc = &gtmr_sc;
-       uint64_t now = armreg_cntv_ct_read();
 
        KASSERT(ci == curcpu());
 
-       ci->ci_lastintr = now;
-
-       /*
-        * Schedule the next interrupt.
-        */
-       now += sc->sc_autoinc;
-       armreg_cntv_tval_write(sc->sc_autoinc);
-
+       int s = splsched();
        /*
         * enable timer and stop masking the timer.
         */
        armreg_cntv_ctl_write(ARM_CNTCTL_ENABLE);
+
+       /*
+        * Get now and update the compare timer.
+        */
+       ci->ci_lastintr = armreg_cntv_ct_read();
+       armreg_cntv_tval_write(sc->sc_autoinc);
+#if 0
+       printf("%s: %s: delta cval = %"PRIu64"\n",
+           __func__, ci->ci_data.cpu_name,
+           armreg_cntv_cval_read() - ci->ci_lastintr);
+#endif
+       splx(s);
 #if 0
        printf("%s: %s: ctl %#x cmp %#"PRIx64" now %#"PRIx64"\n",
            __func__, ci->ci_data.cpu_name, armreg_cntv_ctl_read(),
            armreg_cntv_cval_read(), armreg_cntv_ct_read());
 
-       int s = splsched();
-       uint64_t when = now;
-       u_int n = 0;
-       while ((now = armreg_cntv_ct_read()) < when) {
-               /* spin */
-               n++;
-               KASSERTMSG(n <= sc->sc_autoinc,
-                   "spun %u times but only %"PRIu64" has passed",
-                   n, when - now);
-       }
+       s = splsched();
+
+       uint64_t now64;
+       uint64_t start64 = armreg_cntv_ct_read();
+       do {
+               now64 = armreg_cntv_ct_read();
+       } while (start64 == now64);
+       start64 = now64;
+       uint64_t end64 = start64 + 64;
+       uint32_t start32 = armreg_pmccntr_read();
+       do {
+               now64 = armreg_cntv_ct_read();
+       } while (end64 != now64);
+       uint32_t end32 = armreg_pmccntr_read();
+
+       uint32_t diff32 = end64 - start64;
+       printf("%s: %s: %u cycles per tick\n", 
+           __func__, ci->ci_data.cpu_name, (end32 - start32) / diff32);
+
        printf("%s: %s: status %#x cmp %#"PRIx64" now %#"PRIx64"\n",
            __func__, ci->ci_data.cpu_name, armreg_cntv_ctl_read(),
            armreg_cntv_cval_read(), armreg_cntv_ct_read());
@@ -226,25 +239,33 @@
        const uint64_t now = armreg_cntv_ct_read();
        uint64_t delta = now - ci->ci_lastintr;
 
+#ifdef DIAGNOSTIC
+       const uint64_t then = armreg_cntv_cval_read();
+       KASSERTMSG(then <= now, "%"PRId64, now - then);
+       KASSERTMSG(then - ci->ci_lastintr >= sc->sc_autoinc, "%"PRId64,
+           then - ci->ci_lastintr - sc->sc_autoinc);
+#endif
+
 #if 0
        printf("%s(%p): %s: now %#"PRIx64" delta %"PRIu64"\n", 
             __func__, cf, ci->ci_data.cpu_name, now, delta);
 #endif
        KASSERTMSG(delta > sc->sc_autoinc / 100,
-           "%s: interrupting too quickly (delta=%"PRIu64")",
-           ci->ci_data.cpu_name, delta);
+           "%s: interrupting too quickly (delta=%"PRIu64") autoinc=%lu",
+           ci->ci_data.cpu_name, delta, sc->sc_autoinc);
 
        /*
         * If we got interrutped too soon (delta < sc->sc_autoinc) or
         * we missed a tick (delta >= 2 * sc->sc_autoinc), don't try to
         * adjust for jitter.
         */
-       if (delta < sc->sc_autoinc || delta >= 2 * sc->sc_autoinc) {
+       delta -= sc->sc_autoinc;
+       if (delta < 0 || delta >= sc->sc_autoinc) {
                delta = 0;
        }
        armreg_cntv_tval_write(sc->sc_autoinc - delta);
 
-       ci->ci_lastintr = now;
+       ci->ci_lastintr = now - delta;
 
        hardclock(cf);