Place espradio's RX ring buffer and WiFi-only BSS (ISR tables,
timer slots, ISR ring) in SRAM1 pool 7/6 ahead of the arena.
Frees ~14 KB of SRAM2 for the Go GC heap. The arena assertion
still guarantees ≥32 KB remains for WiFi DMA buffers.
Signed-off-by: deadprogram <ron@hybridgroup.com>
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>
Work around an lld (LLVM 22) bug where l32r PC-relative offsets are
miscalculated when auto-generated .literal.* sections are prepended to
.text.* sections by the linker script. The assembler emits .literal
entries for movi instructions whose constants exceed the 12-bit signed
range; lld then resolves the l32r relocations with incorrect offsets,
causing every l32r in the boot code to load from the wrong literal
pool entry.
The symptom was a TG0WDT_SYS_RESET boot loop: the watchdog disable
code loaded wrong register addresses via l32r and silently wrote to
the wrong peripheral registers, leaving the watchdog running.
Fix by constructing PS_WOE_MASK (0x40000) with movi+slli instead of a
single large-constant movi, eliminating all auto-generated .literal
section entries. This is compatible with both LLVM 20 and LLVM 22.
Also revert DRAM origin to 0x3FFAE000 (200K) and remove rom_phyFuns
symbols that belong in a separate WiFi commit.
Signed-off-by: deadprogram <ron@hybridgroup.com>
Add full flash XIP support for ESP32, enabling code and read-only data to
execute/load directly from flash via the MMU cache rather than consuming
precious SRAM. This increases available RAM from ~328KB to effectively
unlimited for code/rodata, while keeping ~121KB for the Go heap.
Changes:
- src/device/esp/esp32.S: Add MMU initialization in call_start_cpu0
- Call ROM bootloader mmu_init() and cache_flash_mmu_set() to map DROM/IROM
- Enable flash cache via ROM Cache_Read_Enable()
- Fix tinygo_scanCurrentStack to spill all register windows for GC
- targets/esp32-interrupts.S: Add exception diagnostics
- targets/esp32.ld: Major linker script restructure for XIP
- Add DROM (4MB @ 0x3F400000) and IROM (4MB @ 0x400D0000) regions
- Move .rodata to DROM, main .text to IROM (both flash-mapped)
- Keep boot code, vectors, and WiFi blob IRAM sections in SRAM0
- Create WiFi arena in SRAM1 pool 7/6 (64KB @ 0x3FFF0000)
- Move .bss and heap to SRAM2 (200KB @ 0x3FFAE000), avoiding ROM/MAC regions
- Add _drom_flash_addr variable (patched by builder with flash offset)
- targets/esp32.json: Add linker wrap flags for malloc/free and WiFi functions
Signed-off-by: deadprogram <ron@hybridgroup.com>
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.