Previously, the machine.UART0 object had two meanings:
- it was the first UART on the chip
- it was the default output for println
These two meanings conflict, and resulted in workarounds like:
- Defining UART0 to refer to the USB-CDC interface (atsamd21,
atsamd51, nrf52840), even though that clearly isn't an UART.
- Defining NRF_UART0 to avoid a conflict with UART0 (which was
redefined as a USB-CDC interface).
- Defining aliases like UART0 = UART1, which refer to the same
hardware peripheral (stm32).
This commit changes this to use a new machine.Serial object for the
default serial port. It might refer to the first or second UART
depending on the board, or even to the USB-CDC interface. Also, UART0
now really refers to the first UART on the chip, no longer to a USB-CDC
interface.
The changes in the runtime package are all just search+replace. The
changes in the machine package are a mixture of search+replace and
manual modifications.
This commit does not affect binary size, in fact it doesn't affect the
resulting binary at all.
There is no reason to specialize this per chip as it is only ever used
for JavaScript. Not only that, it is causing confusion and is yet
another quirk to learn when porting the runtime to a new
microcontroller.
This is the kind that is used in Go (actually CGo) for exporting
functions. I think it's best to use //export instead of our custom
//go:export pragma, for consistency (they are equivalent in TinyGo).
Therefore I've updated all instances to the standard format (except for
two that are updated in https://github.com/tinygo-org/tinygo/pull/1024).
No smoke tests changed (when comparing the output hash), except for some
wasm tests that include DWARF debug info and tend to be flaky anyway.
This is the same problem as in
https://github.com/tinygo-org/tinygo/pull/605, but other targets also
suffer from it.
Discovered with the GBA target, but as pointed out in
https://bugs.llvm.org/show_bug.cgi?id=42881#c1 this appears to be a bug
in the way external globals are declared, not in LLVM. Therefore I
decided that fixing it everywhere would be the best thing to do.
This commit adds support for software vectoring in the PLIC interrupt.
The interrupt table is created by the compiler, which leads to very
compact code while retaining the flexibility that the interrupt API
provides.
This can be useful for debugging critical bugs in code. I haven't added
human-readable exceptions (such as "illegal instruction" or "stack
overflow") yet, they can be added when they happen in practice (to avoid
increasing code size too much).
This commit adds support for timer interrupts, replacing the busy loop
that was used before. It is perhaps the most simple interrupt to
implement and should serve as the basis for further interrupt support in
RISC-V.
The CLINT is implemented both on the fe310-g002 chip and in the sifive_e
QEMU machine type. Therefore, use that peripheral for consistency.
The only difference is the clock speed, which runs at 10MHz in QEMU for
some reason instead of 32.768kHz as on the physical HiFive1 boards.
QEMU doesn't support the RTC peripheral yet so work around it for now.
This makes the following command work:
tinygo run -target=hifive1-qemu ./testdata/coroutines.go
See the following bug: https://bugs.llvm.org/show_bug.cgi?id=42881
I think this is a bug in LLVM, but the code in question wasn't the best
code anyway. By fixing this, about 16 bytes of code are saved on ARM
chips (and much more on AVR).
Ayke van Laethem
Yannis Huber
Jaden Weiss
Ron Evans