Whole elapsed seconds are added to secs first, so only the remaining subsecond
ticks should then be subtracted from second_countdown in order to decide whether
secs should be incremented again.
Otherwise, secs is not correctly updated in some cases, typically if the bit 7
of ticks is 1. E.g., with ticks = 128 (i.e. exactly 1 s elapsed) and
second_countdown = 128, secs was first incremented as expected, then 128 was
subtracted from second_countdown, giving 0 and triggering an unwanted second
increment of secs. Or with ticks = 129 (i.e. 1 s + 1 tick) and
second_countdown = 1, secs was first incremented as expected, then 129 was
subtracted from second_countdown, giving 128 and missing a second increment of
secs that should have occurred because second_countdown wrapped around.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
During PM1+, the hardware timer used to implement the Contiki clock is frozen,
so clock_adjust() needs to be called when exiting those modes in order to
compensate for the clock ticks missed while the timer was frozen. Doing so
changes the Contiki clock time, so etimer_request_poll() needs to be called in
order to inform the etimer library that an etimer might have expired.
Note that waiting for the next clock ISR to call etimer_request_poll() is
unreliable because the system might go back to sleep beforehand.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
When returning from PM1/2, the sleep timer value (used by RTIMER_NOW()) is not
up-to-date until a positive edge on the 32-kHz clock has been detected after the
system clock restarted. To ensure an updated value is read, wait for a positive
transition on the 32-kHz clock by polling the SYS_CTRL_CLOCK_STA.SYNC_32K bit,
before reading the sleep timer value.
Because of this RTIMER_NOW() fixup, lpm_exit() has to be called at the very
beginning of ISRs waking up the SoC. This also ensures that all clocks and
timers are enabled at the correct frequency and updated before using them
following wake-up.
Without this fix, etimers could sometimes (randomly, depending on timings)
become ultra slow (observed from 10x to 40x slower than normal) if the system
exited PM1/2 very often. This issue occurred more often with PM1.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
As recommended by the CC2538 User's Guide, set SYS_CTRL_CLOCK_CTRL.OSC_PD to 0
before asserting WFI, and set it to 1 after the system clock is sourced from the
32-MHz XOSC following wake-up. This allows to automatically start both
oscillators upon wake-up in order to partially hide the 32-MHz XOSC startup time
by the 16-MHz RCOSC startup time.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
As a matter of precaution, always make sure that pending system clock
transitions are complete before requesting a new change of the system clock
source.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
In one of the abort cases in lpm_enter(), the energest context has previously
been set to LPM, so the abort code needs to set it back to CPU.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Create a dedicated header file with all the definitions for the flash lock bit
page and customer configuration area. This avoids duplicating those definitions
in the startup-gcc.c files of all CC2538-based platforms, and this also allows
to easily manipulate the CCA from outside startup-gcc.c (e.g. for on-the-air
firmware update).
The definitions are now complete contrary to what was in startup-gcc.c:
- Definitions have been added to select the bootloader backdoor pin and active
level if enabled.
- Definitions have been added to access the page and debug lock bits. The debug
lock bit can be used to prevent someone from reading back a programmed
firmware through JTAG if the firmware binary image has to be confidential,
which should be combined with a disabled bootloader backdoor.
- The application entry point is now tied to the beginning of the .text section
instead of to the beginning of the flash. This allows projects using custom
linker scripts to place the application entry point anywhere in the flash,
which can be useful e.g. for on-the-air firmware update.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
SYS_CTRL_EMUOVR is already defined in sys-ctrl.h, so #include this header file
instead of redefining SYS_CTRL_EMUOVR in startup-gcc.c.
Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
It cannot be ruled out that access to the address register triggers
an address auto-increment. Therefore a temporary address register
shadow is introduced to replace the access to the address regsiter.
Additionally there are several minor beautifications.
This patch adds the eeprom driver needed to access M24C64
eeprom which is on some mbxxx boards.
Signed-off-by: Maria Laura Stefanizzi <laura28582@gmail.com>
This patch add the I2C driver for mbxxx platform to communicate with
devices connected to the SC2 I2C bus.
Signed-off-by: Maria Laura Stefanizzi <laura28582@gmail.com>
