This patchseries makes some changes to the clock API: * Remove clock_get_ns() * Add clock_ticks_to_ns() to return number of nanoseconds it will take the clock to tick N times * clock_display_freq() to return prettily-formatted string for showing humans the approximate clock frequency
This is based on discussions we had about these APIs a little while back. The core driver here is that the clock objects internally store the period in units of 2^-32 ns, so both clock_get_ns() and clock_get_hz() are inherently returning a rounded-off result, which can be badly inaccurate for fast clocks or if you want to multiply it by a large tick count. Ideally I'd like to get rid of clock_get_hz() as well, but that looks trickier than handling clock_get_ns(). Patch 4 borrows a lot of the concept from one of Philippe's that he sent out previously. NB: tested with 'make check' and 'make check-acceptance' only. Changes v1->v2: * In patch 1, saturate return value to INT64_MAX (and update docs to explain this and why) Patches 2-4 have been reviewed, only patch 1 needs review. thanks -- PMM Peter Maydell (4): clock: Introduce clock_ticks_to_ns() target/mips: Don't use clock_get_ns() in clock period calculation clock: Remove clock_get_ns() clock: Define and use new clock_display_freq() docs/devel/clocks.rst | 51 ++++++++++++++++++++++++++++++++++++---- include/hw/clock.h | 53 +++++++++++++++++++++++++++++++++++++++--- hw/core/clock.c | 6 +++++ softmmu/qdev-monitor.c | 6 ++--- target/mips/cpu.c | 4 ++-- 5 files changed, 108 insertions(+), 12 deletions(-) -- 2.20.1
