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| author | Bryan O'Donoghue <bryan.odonoghue@linaro.org> | 2016-06-10 16:10:12 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@google.com> | 2016-06-10 16:26:31 -0700 |
| commit | 4c2f8a48e989c323e4fb378f95ceaa8091760832 (patch) | |
| tree | 9317087426feaffdd03152c494ffea8679ac3f2c /drivers/staging/greybus/timesync.c | |
| parent | 6db9cc68d7f9cea440293af4225a7b7f22d1d86d (diff) | |
| download | op-kernel-dev-4c2f8a48e989c323e4fb378f95ceaa8091760832.zip op-kernel-dev-4c2f8a48e989c323e4fb378f95ceaa8091760832.tar.gz | |
greybus: timesync: Do 64 bit divisions in a 32 friendly way
We need to use 'do_div()' when doing 64 bit division or modulo division
since the kernel will not pull in the gcc builtins __aeabi_ldivmod and
__aeabi_uldivmod on 32 bit builds.
Reported-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Diffstat (limited to 'drivers/staging/greybus/timesync.c')
| -rw-r--r-- | drivers/staging/greybus/timesync.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/drivers/staging/greybus/timesync.c b/drivers/staging/greybus/timesync.c index 87cbe10..a029fa0 100644 --- a/drivers/staging/greybus/timesync.c +++ b/drivers/staging/greybus/timesync.c @@ -502,8 +502,7 @@ static int gb_timesync_to_timespec(struct gb_timesync_svc *timesync_svc, u64 frame_time, struct timespec *ts) { unsigned long flags; - u64 delta_fs, counts; - u32 sec, nsec; + u64 delta_fs, counts, sec, nsec; bool add; int ret = 0; @@ -532,8 +531,15 @@ static int gb_timesync_to_timespec(struct gb_timesync_svc *timesync_svc, /* Determine the time difference in femtoseconds */ delta_fs = counts * gb_timesync_fs_per_clock; - sec = delta_fs / FSEC_PER_SEC; - nsec = (delta_fs % FSEC_PER_SEC) / 1000000UL; + + /* Convert to seconds */ + sec = delta_fs; + do_div(sec, NSEC_PER_SEC); + do_div(sec, 1000000UL); + + /* Get the nanosecond remainder */ + nsec = do_div(delta_fs, sec); + do_div(nsec, 1000000UL); if (add) { /* Add the calculated offset - overflow nanoseconds upwards */ @@ -548,7 +554,7 @@ static int gb_timesync_to_timespec(struct gb_timesync_svc *timesync_svc, if (nsec > timesync_svc->ktime_data.ts.tv_nsec) { sec++; nsec = nsec + timesync_svc->ktime_data.ts.tv_nsec; - nsec %= NSEC_PER_SEC; + nsec = do_div(nsec, NSEC_PER_SEC); } else { nsec = timesync_svc->ktime_data.ts.tv_nsec - nsec; } @@ -1318,8 +1324,10 @@ int __init gb_timesync_init(void) gb_timesync_clock_rate = gb_timesync_platform_get_clock_rate(); /* Calculate nanoseconds and femtoseconds per clock */ - gb_timesync_fs_per_clock = FSEC_PER_SEC / gb_timesync_clock_rate; - gb_timesync_ns_per_clock = NSEC_PER_SEC / gb_timesync_clock_rate; + gb_timesync_fs_per_clock = FSEC_PER_SEC; + do_div(gb_timesync_fs_per_clock, gb_timesync_clock_rate); + gb_timesync_ns_per_clock = NSEC_PER_SEC; + do_div(gb_timesync_ns_per_clock, gb_timesync_clock_rate); /* Calculate the maximum number of clocks we will convert to ktime */ gb_timesync_max_ktime_diff = |
