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4 commits

Author SHA1 Message Date
Andy Ross 7832738ae9 kernel/timeout: Make timeout arguments an opaque type
Add a k_timeout_t type, and use it everywhere that kernel API
functions were accepting a millisecond timeout argument.  Instead of
forcing milliseconds everywhere (which are often not integrally
representable as system ticks), do the conversion to ticks at the
point where the timeout is created.  This avoids an extra unit
conversion in some application code, and allows us to express the
timeout in units other than milliseconds to achieve greater precision.

The existing K_MSEC() et. al. macros now return initializers for a
k_timeout_t.

The K_NO_WAIT and K_FOREVER constants have now become k_timeout_t
values, which means they cannot be operated on as integers.
Applications which have their own APIs that need to inspect these
vs. user-provided timeouts can now use a K_TIMEOUT_EQ() predicate to
test for equality.

Timer drivers, which receive an integer tick count in ther
z_clock_set_timeout() functions, now use the integer-valued
K_TICKS_FOREVER constant instead of K_FOREVER.

For the initial release, to preserve source compatibility, a
CONFIG_LEGACY_TIMEOUT_API kconfig is provided.  When true, the
k_timeout_t will remain a compatible 32 bit value that will work with
any legacy Zephyr application.

Some subsystems present timeout (or timeout-like) values to their own
users as APIs that would re-use the kernel's own constants and
conventions.  These will require some minor design work to adapt to
the new scheme (in most cases just using k_timeout_t directly in their
own API), and they have not been changed in this patch, instead
selecting CONFIG_LEGACY_TIMEOUT_API via kconfig.  These subsystems
include: CAN Bus, the Microbit display driver, I2S, LoRa modem
drivers, the UART Async API, Video hardware drivers, the console
subsystem, and the network buffer abstraction.

k_sleep() now takes a k_timeout_t argument, with a k_msleep() variant
provided that works identically to the original API.

Most of the changes here are just type/configuration management and
documentation, but there are logic changes in mempool, where a loop
that used a timeout numerically has been reworked using a new
z_timeout_end_calc() predicate.  Also in queue.c, a (when POLL was
enabled) a similar loop was needlessly used to try to retry the
k_poll() call after a spurious failure.  But k_poll() does not fail
spuriously, so the loop was removed.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-03-31 19:40:47 -04:00
Kumar Gala e7df99d4ee drivers: cc13xx_cc26xx: Convert drivers to new DT_INST macros
Convert older DT_INST_ macro use in cc13xx_cc26xx drivers to the new
include/devicetree.h DT_INST macro APIs.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2020-03-26 05:20:19 -05:00
Andy Ross 5f63c9d907 drivers/timer: Clamp after tick adjustment, not before
Some early tickless drivers had a common pattern where they would
compute a tick maximum for the request (i.e. the maximum the hardware
counter can handle) but apply it only on the input tick value and not
on the adjusted final value, opening up the overflow condition it was
supposed to have prevented.

Fixes #20939 (Strictly it fixes the specific pattern that was
discovered in that bug.  It's not impossible that other drivers with
alternative implementations have a similar issue, though they look OK
to me via a quick audit).

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-11-27 18:43:53 +01:00
Vincent Wan aeb8d017b5 drivers: timer: add RTC support as system clock for CC13X2/CC26X2
Add RTC timer driver for CC13X2/CC26X2, and use it instead of systick
as system clock. It is necessary to use this timer for power
management support, so that the system can exit from deep sleep upon
expiry of timeouts.

Signed-off-by: Vincent Wan <vincent.wan@linaro.org>
2019-09-19 13:43:10 -05:00