diff options
| author | James Hogan <james.hogan@imgtec.com> | 2016-04-22 18:19:14 +0100 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2016-05-13 15:30:25 +0200 |
| commit | aab4673b599d8037c713afce40fabae398ca96c4 (patch) | |
| tree | e87f94a86ebe3ac3cca6ad7e444d439e08bf6776 /arch/mips | |
| parent | 6b8322576e9d325b65c54fbef64e4e8690ad70ce (diff) | |
| download | linux-aab4673b599d8037c713afce40fabae398ca96c4.tar.bz2 | |
MIPS: malta-time: Start GIC count before syncing to RTC
The sampling of the GIC counter on Malta after observing a rising edge
of the RTC update flag differs slightly between the first and second
sample, with the first sample also calling gic_start_count(). The two
samples should really be taken as similarly as possible to get the most
accurate figure, so move the gic_start_count() call before detecting the
rising edge.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13173/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips')
| -rw-r--r-- | arch/mips/mti-malta/malta-time.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c index b7bf721eabf5..2539687b77f6 100644 --- a/arch/mips/mti-malta/malta-time.c +++ b/arch/mips/mti-malta/malta-time.c @@ -81,16 +81,16 @@ static void __init estimate_frequencies(void) local_irq_save(flags); - /* Start counter exactly on falling edge of update flag. */ + if (gic_present) + gic_start_count(); + + /* Read counter exactly on falling edge of update flag. */ while (CMOS_READ(RTC_REG_A) & RTC_UIP); while (!(CMOS_READ(RTC_REG_A) & RTC_UIP)); - /* Initialize counters. */ start = read_c0_count(); - if (gic_present) { - gic_start_count(); + if (gic_present) gicstart = gic_read_count(); - } /* Read counter exactly on falling edge of update flag. */ while (CMOS_READ(RTC_REG_A) & RTC_UIP); |