This commit adds a new tool called mpy_ld.py which is essentially a linker
that builds .mpy files directly from .o files. A new header file
(dynruntime.h) and makefile fragment (dynruntime.mk) are also included
which allow building .mpy files from C source code. Such .mpy files can
then be dynamically imported as though they were a normal Python module,
even though they are implemented in C.
Converting .o files directly (rather than pre-linked .elf files) allows the
resulting .mpy to be more efficient because it has more control over the
relocations; for example it can skip PLT indirection. Doing it this way
also allows supporting more architectures, such as Xtensa which has
specific needs for position-independent code and the GOT.
The tool supports targets of x86, x86-64, ARM Thumb and Xtensa (windowed
and non-windowed). BSS, text and rodata sections are supported, with
relocations to all internal sections and symbols, as well as relocations to
some external symbols (defined by dynruntime.h), and linking of qstrs.
Usage:
mpy-tool.py -o merged.mpy --merge mod1.mpy mod2.mpy
The constituent .mpy files are executed sequentially when the merged file
is imported, and they all use the same global namespace.
Implements text, rodata and bss generalised relocations, as well as generic
qstr-object linking. This allows importing dynamic native modules on all
supported architectures in a unified way.
The size of the event ringbuf was previously fixed to compile-time config
value, but it's necessary to sometimes increase this for applications that
have large characteristic buffers to read, or many events at once.
With this commit the size can be set via BLE.config(rxbuf=512), for
example. This also resizes the internal event data buffer which sets the
maximum size of incoming data passed to the event handler.
This allows the user to explicitly select the behaviour of the write to the
remote peripheral. This is needed for peripherals that have
characteristics with WRITE_NO_RESPONSE set (instead of normal WRITE). The
function's signature is now:
BLE.gattc_write(conn_handle, value_handle, data, mode=0)
mode=0 means write without response, while mode=1 means write with
response. The latter was the original behaviour so this commit is a change
in behaviour of this method, and one should specify 1 as the 4th argument
to get back the old behaviour.
In the future there could be more modes supported, such as long writes.
The default protection for the BLE ringbuf is to use
MICROPY_BEGIN_ATOMIC_SECTION, which disables all interrupts. On stm32 it
only needs to disable the lowest priority IRQ, pendsv, because that's the
IRQ level at which the BLE stack is driven.
This removes the limit on data coming in from a BLE.gattc_read() request,
or a notify with payload (coming in to a central). In both cases the data
coming in to the BLE callback is now limited only by the available data in
the ringbuf, whereas before it was capped at (default hard coded) 20 bytes.
Instead of enqueue_irq() inspecting the ringbuf to decide whether to
schedule the IRQ callback (if ringbuf is empty), maintain a flag that knows
if the callback is on the schedule queue or not. This saves about 150
bytes of code (for stm32 builds), and simplifies all uses of enqueue_irq()
and schedule_ringbuf().
qstrs in this file are always included in all builds, even if not used
anywhere. So remove those that are never needed, and make USB names
conditional on having USB enabled.
With the memcpy() call placed last it avoids the effects of registers
clobbering. It's definitely effective in non-inlined functions, but even
here it is still making a small difference. For example, on stm32, this
saves an extra `ldr` instruction to load `o->vstr` after the memcpy()
returns.
The string length being longer than the allowed qstr length can happen in
many locations, for example in the parser with very long variable names.
Without an explicit check that the length is within range (as done in this
patch) the code would exhibit crashes and strange behaviour with truncated
strings.
And return -MP_EIO if calling storage_read_block/storage_write_block fails.
This lines up with the return type and value (negative for error) of the
calls to MICROPY_HW_BDEV_READBLOCKS (and WRITEBLOCKS, and BDEV2 versions).
