Remove unused cpuIntUsed and cpuIntToPeripheral variables from
interrupt_esp32.go because these were declared but never read.
Fix _globals_end in the linker script to cover .data in addition to
.bss and .wifi_bss. Previously the GC scan range ended at
_wifi_bss_end, missing any heap pointers stored in initialized
globals (.data section). Extend to _edata so the conservative
collector sees all global root pointers.
Signed-off-by: deadprogram <ron@hybridgroup.com>
This adds a minimal esp32c6 implementation, currently only
supporting the examples/serial and examples/blinky1 programs.
It does correctly output the expected "Hello, World" via the
serial port, as well as blink the onboard LED.
In addition, it adds support for the PLIC based IRQ handling
as used on the ESP32C6 processor.
Some parts of this code are loosely based on PR #5252 and #5248
Signed-off-by: deadprogram <ron@hybridgroup.com>
* gba: add bios interrupt flags
Adds a new GBA register for interrupt flags, the register is equivalent
to the IF register, but is intended for BIOS functions.
Acknowledging the interrupts with this register allows us to use BIOS
halt functions such as VBlankIntrWait and IntrWait, which we can use to
get rid of busy loops in the GBA code.
* fix formatting
---------
Co-authored-by: zoey <git@zoey.si>
Realized this while looking through the code: there is no way to use
this safely when the scheduler is involved. It can only be used safely
with a `wfe` or similar (part of scheduler code).
When SPI is configured via the GPIO Matrix, SPI signal transitions set
GPIO.STATUS bits on the routed pins. With a level-triggered CPU interrupt
(line 8), the ISR re-enters continuously as long as any STATUS bit is
asserted — causing user GPIO callbacks to fire spuriously.
Switch cpuInterruptFromPin to CPU interrupt 10, which is edge-triggered
(level 1) on the Xtensa LX7. This ensures the ISR fires once per GPIO
event rather than looping while SPI is active.
Also move STATUS_W1TC clears to before callback dispatch so that new
GPIO events arriving during handler execution generate a fresh edge, and
add writeINTCLEAR(active) in handleInterrupt to properly acknowledge
edge-triggered CPU interrupt pending bits via the INTCLEAR register.
Fixes GPIO interrupts firing constantly when SPI and pin interrupts are
used together.
Signed-off-by: deadprogram <ron@hybridgroup.com>
Replace the minimal inline ISR (which only disabled INTENABLE) with a
full level-1 interrupt handler that saves/restores the interrupted
context and dispatches to Go's handleInterrupt.
The handler uses callx4 (not callx0) to call into Go code because:
- callx0 does not set PS.CALLINC, so the Go function's entry
instruction uses stale CALLINC from the interrupted code, causing
wrong window rotation and a garbage stack pointer.
- callx4 explicitly sets CALLINC=1, and our frame pointer (a1) is
outside the callee's register window so it is preserved.
Also updates the USB Serial/JTAG ISR to disable INT_ENA (peripheral
level) instead of relying on INTENABLE, and adds signalInterrupt to
the dispatcher so sleepTicks can be woken by any interrupt.
* esp32s3: add interrupt support
This finally adds the long awaited support for interrupts on the
Xtensa arch. Initially just for the ESP32-S3 but then others.
Signed-off-by: deadprogram <ron@hybridgroup.com>
* esp32s3: get interrupts working correctly
There were a number of needed changes in order to get interrupts correctly working
on the esp32s3 processor:
- PS.UM=1 in interruptInit() - routed interrupts to user exception vector (0x340)
instead of kernel (0x300)
- Inline ISR in the vector slot - external handlers via j/call0 crashed (likely
clang Xtensa literal pool issue with large movi constants in separate sections)
- Disable INTENABLE (not just INT_CLR) - the USB RX interrupt is level-triggered;
clearing INT_CLR alone causes infinite re-entry since data is still in the FIFO
- Buffered() re-enables INTENABLE after draining the hardware FIFO
Signed-off-by: deadprogram <ron@hybridgroup.com>
---------
Signed-off-by: deadprogram <ron@hybridgroup.com>
MCAUSE was never being cleared after handling an interrupt.
On RISC-V, mret does NOT zero MCAUSE — it retains the last
trap cause. Every other TinyGo RISC-V target (FE310, K210,
QEMU) explicitly does riscv.MCAUSE.Set(0) after handling.
The ESP32-C3 was missing this.
Signed-off-by: deadprogram <ron@hybridgroup.com>
This type can be used to jump back to a previous position in a program
from inside an interrupt. This is useful for baremetal systems that
implement wfi but not wfe, and therefore have no easy (race-free) way to
wait until a flag gets changed inside an interrupt. This is an issue on
RISC-V, where this is racy (the interrupt might happen after the check
but before the wfi instruction):
configureInterrupt()
for flag.Load() != 0 {
riscv.Asm("wfi")
}
Without this change, a pending interrupt would spuriously trigger
immediately after enabling. This happens if an interrupt is triggered
during flashing (e.g. by DMA), which survives the subsequent reset.
This behaviour matches e.g. `machine.irqSet` in machine_rp2_rp2350.go.
See 7f970a45, whose symptoms were likely caused by spurious interrupts.
TODO: Remove the go.mod/go.sum in internal/tools once doing so doesn't break CI (e.g. once we drop support for go 1.19)
* builder/cc1as.h: fix typo found by 'make spell'
* GNUmakefile: remove exception for inbetween, fix instance now found by 'make spell'
* GNUmakefile: remove exception for programmmer, fix instance now found by 'make spell'
* go.mod: use updated misspell. GNUmakefile: add spellfix target, use it.
* ignore directories properly when invoking spellchecker.
* make spell: give internal/tools its own go.mod, as misspell requires newer go
* make lint: depend on tools and run the installed revive
(which was perhaps implied by the change that added revive to internal/tools,
but not required in GNUmakefile until we gave internal/tools its own temporary go.mod)
* .github: now that 'make spell' works well, run it from CI
* GNUmakefile: make spell now aborts if it finds misspelt words, so what it finds doesn't get lost in CI logs
* GNUmakefile: tools: avoid -C option on go generate to make test-llvm15-go119 circleci job happy, see
https://cs.opensource.google/go/go/+/2af48cbb7d85e5fdc635e75b99f949010c607786
* internal/tools/go.mod: fix format of go version to leave out patchlevel, else go complains.
We have an optimization for this specific pattern, but it's really just
a hack. With the addition of unsafe.Add in Go 1.17 we can directly
specify the intent instead and eventually remove this special case.
The code is also easier to read.
Go 1.19 started reformatting code in a way that makes it more obvious
how it will be rendered on pkg.go.dev. It gets it almost right, but not
entirely. Therefore, I had to modify some of the comments so that they
are formatted correctly.
Update interrupt_esp32c3.go:
make callHandler inline
save and restore MSTATUS along with MEPC
save and restore actual threshold value and call fence
print additional data during exception
Do it all at once in preparation for Go 1.18 support.
To make this commit, I've simply modified the `fmt-check` Makefile
target to rewrite files instead of listing the differences. So this is a
fully mechanical change, it should not have introduced any errors.
Instead of doing everything in the interrupt lowering pass, generate
some more code in gen-device to declare interrupt handler functions and
do some work in the compiler so that interrupt lowering becomes a lot
simpler.
This has several benefits:
- Overall code is smaller, in particular the interrupt lowering pass.
- The code should be a bit less "magical" and instead a bit easier to
read. In particular, instead of having a magic
runtime.callInterruptHandler (that is fully written by the interrupt
lowering pass), the runtime calls a generated function like
device/sifive.InterruptHandler where this switch already exists in
code.
- Debug information is improved. This can be helpful during actual
debugging but is also useful for other uses of DWARF debug
information.
For an example on debug information improvement, this is what a
backtrace might look like before this commit:
Breakpoint 1, 0x00000b46 in UART0_IRQHandler ()
(gdb) bt
#0 0x00000b46 in UART0_IRQHandler ()
#1 <signal handler called>
[..etc]
Notice that the debugger doesn't see the source code location where it
has stopped.
After this commit, breaking at the same line might look like this:
Breakpoint 1, (*machine.UART).handleInterrupt (arg1=..., uart=<optimized out>) at /home/ayke/src/github.com/tinygo-org/tinygo/src/machine/machine_nrf.go:200
200 uart.Receive(byte(nrf.UART0.RXD.Get()))
(gdb) bt
#0 (*machine.UART).handleInterrupt (arg1=..., uart=<optimized out>) at /home/ayke/src/github.com/tinygo-org/tinygo/src/machine/machine_nrf.go:200
#1 UART0_IRQHandler () at /home/ayke/src/github.com/tinygo-org/tinygo/src/device/nrf/nrf51.go:176
#2 <signal handler called>
[..etc]
By now, the debugger sees an actual source location for UART0_IRQHandler
(in the generated file) and an inlined function.
This is only very minimal support. More support (such as tinygo flash,
or peripheral access) should be added in later commits, to keep this one
focused.
Importantly, this commit changes the LLVM repo from llvm/llvm-project to
tinygo-org/llvm-project. This provides a little bit of versioning in
case something changes in the Espressif fork. If we want to upgrade to
LLVM 11 it's easy to switch back to llvm/llvm-project until Espressif
has updated their fork.
Thanks to Kyle Lemons for the inspiration and original design. The
implementation in this commit is very different however, building on top
of the software vectoring needed in RISC-V. The result is a flexible
interrupt handler that does not take up any RAM for configuration.
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 commit lets the compiler know about interrupts and allows
optimizations to be performed based on that: interrupts are eliminated
when they appear to be unused in a program. This is done with a new
pseudo-call (runtime/interrupt.New) that is treated specially by the
compiler.
Matthew Hiles
deadprogram
zowhoey
Ayke van Laethem
Elias Naur
Dan Kegel
dkegel-fastly
Yurii Soldak
Dmitriy
Ethan Reesor
Yannis Huber
Jaden Weiss