[src/trunk]: src/sys/arch/alpha/alpha Don't use the PCC timecunter on emulate...

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

details:   https://anonhg.NetBSD.org/src/rev/d2d4696eedfe
branches:  trunk
changeset: 955391:d2d4696eedfe
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sun Sep 27 23:17:36 2020 +0000

description:
Don't use the PCC timecunter on emulated Qemu systems.

diffstat:

 sys/arch/alpha/alpha/clock.c |  15 +++++++++------
 1 files changed, 9 insertions(+), 6 deletions(-)

diffs (51 lines):

diff -r 735c1c8f6d7c -r d2d4696eedfe sys/arch/alpha/alpha/clock.c
--- a/sys/arch/alpha/alpha/clock.c      Sun Sep 27 23:16:10 2020 +0000
+++ b/sys/arch/alpha/alpha/clock.c      Sun Sep 27 23:17:36 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: clock.c,v 1.43 2020/09/04 03:41:49 thorpej Exp $ */
+/* $NetBSD: clock.c,v 1.44 2020/09/27 23:17:36 thorpej Exp $ */
 
 /*
  * Copyright (c) 1988 University of Utah.
@@ -39,7 +39,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.43 2020/09/04 03:41:49 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: clock.c,v 1.44 2020/09/27 23:17:36 thorpej Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -47,6 +47,7 @@
 #include <sys/device.h>
 #include <sys/lwp.h>
 
+#include <machine/alpha.h>
 #include <machine/autoconf.h>
 #include <machine/cpuconf.h>
 #include <machine/cpu_counter.h>
@@ -78,7 +79,6 @@
 void
 cpu_initclocks(void)
 {
-       uint64_t pcc_freq;
 
        if (clock_init == NULL)
                panic("cpu_initclocks: no clock attached");
@@ -99,10 +99,13 @@
        schedhz = 16;
 
        /*
-        * Initialize PCC timecounter.
+        * Initialize PCC timecounter, unless we're running in Qemu
+        * (we will use a different timecounter in that case).
         */
-       pcc_freq = cpu_frequency(curcpu());
-       cc_init(NULL, pcc_freq, "PCC", PCC_QUAL);
+       if (! alpha_is_qemu) {
+               const uint64_t pcc_freq = cpu_frequency(curcpu());
+               cc_init(NULL, pcc_freq, "PCC", PCC_QUAL);
+       }
 
        /*
         * Get the clock started.