[src/trunk]: src/sys/arch/evbarm/dev Don't write FBRD/IBRD if ref clk frequen...

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

details:   https://anonhg.NetBSD.org/src/rev/496bdb6b2f80
branches:  trunk
changeset: 836351:496bdb6b2f80
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Fri Oct 12 23:57:00 2018 +0000

description:
Don't write FBRD/IBRD if ref clk frequency is unknown

diffstat:

 sys/arch/evbarm/dev/plcom.c |  16 ++++++++++------
 1 files changed, 10 insertions(+), 6 deletions(-)

diffs (44 lines):

diff -r 8384c084be97 -r 496bdb6b2f80 sys/arch/evbarm/dev/plcom.c
--- a/sys/arch/evbarm/dev/plcom.c       Fri Oct 12 23:26:41 2018 +0000
+++ b/sys/arch/evbarm/dev/plcom.c       Fri Oct 12 23:57:00 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: plcom.c,v 1.54 2018/10/12 22:18:38 jmcneill Exp $      */
+/*     $NetBSD: plcom.c,v 1.55 2018/10/12 23:57:00 jmcneill Exp $      */
 
 /*-
  * Copyright (c) 2001 ARM Ltd
@@ -94,7 +94,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: plcom.c,v 1.54 2018/10/12 22:18:38 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: plcom.c,v 1.55 2018/10/12 23:57:00 jmcneill Exp $");
 
 #include "opt_plcom.h"
 #include "opt_ddb.h"
@@ -1537,8 +1537,10 @@
        switch (pi->pi_type) {
        case PLCOM_TYPE_PL010:
                PWRITE1(pi, PL010COM_CR, 0);
-               PWRITE1(pi, PL010COM_DLBL, sc->sc_ratel);
-               PWRITE1(pi, PL010COM_DLBH, sc->sc_rateh);
+               if (sc->sc_frequency != 0) {
+                       PWRITE1(pi, PL010COM_DLBL, sc->sc_ratel);
+                       PWRITE1(pi, PL010COM_DLBH, sc->sc_rateh);
+               }
                PWRITE1(pi, PL010COM_LCR, sc->sc_lcr);
 
                /* XXX device_unit() abuse */
@@ -1552,8 +1554,10 @@
 
        case PLCOM_TYPE_PL011:
                PWRITE4(pi, PL011COM_CR, 0);
-               PWRITE1(pi, PL011COM_FBRD, sc->sc_ratel);
-               PWRITE4(pi, PL011COM_IBRD, sc->sc_rateh);
+               if (sc->sc_frequency != 0) {
+                       PWRITE1(pi, PL011COM_FBRD, sc->sc_ratel);
+                       PWRITE4(pi, PL011COM_IBRD, sc->sc_rateh);
+               }
                PWRITE1(pi, PL011COM_LCRH, sc->sc_lcr);
                sc->sc_mcr_active = sc->sc_mcr;
                CLR(sc->sc_cr, PL011_MCR(PL01X_MCR_RTS | PL01X_MCR_DTR));