In rtos-less code, heap is defined by assuming one-region. Through weak-reference to
ARM_LIB_HEAP, heap definition is fixed if ARM_LIB_HEAP is defined.
Once a fatal error is in progress, it's not useful to trap RTX errors
or mutex problems, so short-circuit the checks.
This makes it more likely that we may be able to get the console
initialised if it is being written to for the first time by `mbed_error`
in a difficult context - such as an RTX error callback from inside an
SVCall.
For example, the one-line program
osMutexAcquire(NULL, 0);
will generate an RTX error trap, then `mbed_error` will try to call
`write(STDERR_FILENO)` to print the error, which will prompt mbed_retarget to
construct a singleton `UARTSerial`. This would trap in the mutex
for the singleton or the construction of the UARTSerial itself, if
we didn't allow this leniency. If we clear the mutex checks, then
`UARTSerial::write_unbuffered` will work.
Assert failure took a critical section before calling `mbed_error`.
There's no need to take a critical section on assert failure -
mbed_error does not do this, and is designed to operate from normal
contexts.
Avoiding the critical section will improve the chances of console
initialisation due to assert failure working nicely.
User uses of `MBED_MAKE_ERROR` assemble a new error that gets its bottom
16 bits from an existing negative 32-bit error code. This lead to
undefined behaviour when `<<` was used on it - even though it was a
shift by zero!
Avoid the undefined behaviour warning from Clang by masking before
shifting.
This provides the ability to generate really small delays - it's often
the case that wait_us() takes multiple microseconds to set up, so
having an alternative suitable for <10us delays is useful.
There have been a few local implementations - it makes sense to
centralise them as they need retuning for each new ARM core.
Based on the local implementation inside the Atmel 802.15.4 driver.
Add a necessary helper to allow FileHandle objects to be obtained
from POSIX file descriptors.
Primary envisaged use case is to act on STDIN_FILENO etc, eg to
set it non-blocking or use sigio, or to use the enable API.
Add API to dynamically enable/disable input and output on FileHandles.
Aim is to allow power saving by indicating that we permanently or
temporarily do not require input, so that for example serial Rx
interrupts can be released, and deep sleep permitted.
Memory model for RTOS and No RTOS was initially single stack and heap,
only few targets implemented 2-region RAM model.
2-region RAM model is applied for all toolchains and targets.
GCC: __wrap__sbrk was implemented for 2-region ram model, with switch to 2-region
for all targets, we do not need target specific implementation of this API
Also _sbrk is WEAK function, hence can be over written in target folder for
special cases
The following commits: #8039, #9092 added Boot/ISR stack definition to all scatter files (ARM_LIB_STACK).
This has changed memory model for RTOS-less builds to 2-region memory model and caused failure in case of rtos less builds.
This PR defines valid heap/stack regions for rtos-less builds.
adbridge
M. Rahimi
ccli8
Kevin Bracey
Shrikant Tudavekar
Martin Kojtal
d-kato
Michael Schwarcz
David Saada
Mahesh Mahadevan
Martin Kojtal
deepikabhavnani
Cruz Monrreal
Senthil Ramakrishnan
Jimmy Brisson
Sarah Marsh
Przemyslaw Stekiel