esp32: Add machine module with GPIO object

Author: aykevl

ports/common/rules.mk

@@ -28,6 +28,10 @@ $(BUILD)/os.o: $(SRC_GO_OS) $(BUILD)/syscall.o
 @echo "Go $@"
 $(Q)$(GCCGO) $(GOFLAGS) -fgo-pkgpath=os -c -o $@ $(SRC_GO_OS)
 
+$(BUILD)/machine.o: $(SRC_GO_MACHINE)
+@echo "Go $@"
+$(Q)$(GCCGO) $(GOFLAGS) -fgo-pkgpath=machine -c -o $@ $(SRC_GO_MACHINE)
+
 # Build libgo C sources.
 # TODO: this uses gnu99 to work around undefined stack_t
 $(BUILD)/libgo/%.o: $(GCCREPO)/libgo/runtime/%.c

ports/esp32/Makefile

@@ -8,6 +8,9 @@ include ../common/vars.mk
 SRC_C_PORT += main.c
 SRC_GO_RUNTIME += runtime.go
 SRC_GO_OS += os.go
+SRC_GO_MACHINE += machine.go
+
+LIBS += $(BUILD)/machine.o
 
 all: mkdir $(LIBS) $(BUILD)/esp32_out.ld #$(BUILD)/bootloader.bin
 

ports/esp32/machine.go

@@ -0,0 +1,71 @@
+
+package machine
+
+func gpio_config(*gpio_config_t) uint __asm__("gpio_config")
+func gpio_set_direction(uint, uint) uint __asm__("gpio_set_direction")
+func gpio_set_level(uint, uint32) uint __asm__("gpio_set_level")
+func gpio_get_level(uint) int __asm__("gpio_get_level")
+
+type gpio_config_t struct {
+pin_bit_mask uint64
+mode uint8
+pull_up_en uint8
+pull_down_en uint8
+gpio_int_type uint8
+}
+
+const (
+GPIO_DISABLE = 0
+GPIO_INPUT = 1
+GPIO_OUTPUT = 2
+GPIO_OPEN_DRAIN = 4
+)
+
+const (
+GPIO_PULLUP = iota
+GPIO_PULLDOWN
+GPIO_PULLBOTH
+GPIO_FLOATING
+)
+
+type GPIO struct {
+pin uint
+}
+
+type GPIOConfig struct {
+Mode uint8
+Pull uint8 // TODO
+}
+
+func (p *GPIO) Configure(config GPIOConfig) {
+c := gpio_config_t{
+pin_bit_mask: 1 << p.pin,
+mode: config.Mode,
+}
+gpio_config(&c)
+}
+
+func (p *GPIO) Set(value bool) {
+level := uint32(0)
+if value {
+level = 1
+}
+gpio_set_level(p.pin, level)
+}
+
+func (p *GPIO) Get() bool {
+level := gpio_get_level(p.pin)
+if level != 0 {
+return true
+}
+return false
+}
+
+// TODO: split the rest of this module into a board package.
+
+var (
+GPIO2 = GPIO{2}
+GPIO4 = GPIO{4}
+)
+
+var LED_BUILTIN = GPIO2

ports/esp32/main.c

@@ -9,9 +9,12 @@ esp_err_t event_handler(void *ctx, system_event_t *event)
 return ESP_OK;
 }
 
+void machine_init() __asm__("machine..import");
+
 void app_main(void)
 {
 //go_init(); // TODO
+machine_init();
 go_main();
 
 // sleep forever

tinygo

@@ -29,12 +29,16 @@ if len(args) >= 2:
 if mcu == 'esp32':
  os.environ['GOOS'] = 'esp32'
  os.environ['GOARCH'] = 'xtensa'
+ port = 'esp32'
 elif mcu is not None:
  print('unknown MCU:', mcu, file=sys.stdout)
  sys.exit(1)
+else:
+ port = 'unix'
 
 # for tinygo-gccgo
 os.environ['TINYGO_LTO'] = str(int(lto))
+os.environ['TINYGO_PORT'] = port
 if mcu:
  os.environ['TINYGO_MCU'] = mcu
 
@@ -62,5 +66,6 @@ os.environ['PATH'] = TINYGO + '/bin:' + os.environ['PATH']
 os.environ['GOROOT'] = TINYGO + '/goroot' # set GOROOT to fake runtime etc. packages
 os.environ['GOPATH'] = os.environ.get('GOPATH', os.environ['HOME'] + '/go') # set default GOPATH
 os.environ['GOPATH'] += ':' + TINYGO + '/libgo' # append standard library
+os.environ['GOPATH'] += ':%s/ports/%s/build' % (TINYGO, port)
 
 sys.exit(subprocess.run(args).returncode)

tinygo-cmd

@@ -8,6 +8,7 @@ TOOLCHAIN = os.environ.get('TOOLCHAIN', '')
 TINYGO = os.path.dirname(os.path.realpath(__file__))
 MCU = os.environ.get('TINYGO_MCU') or None
 LTO = bool(int(os.environ.get('TINYGO_LTO')))
+PORT = os.environ['TINYGO_PORT']
 
 CC = TOOLCHAIN + 'gcc'
 GCCGO = TOOLCHAIN + 'gccgo'
@@ -36,17 +37,13 @@ def get_lib_path(name):
  sys.exit(cmd.returncode)
  return cmd.stdout.decode('utf-8').strip()
 
-port = 'unix'
-if MCU == 'esp32':
- port = 'esp32'
-
 def wrapActionCompileC():
  # Compiling C code
  cmd[0] = CC
  cmd.extend(FLAGS)
  cmd.append('-I%s/goroot/src/runtime' % TINYGO)
  cmd.append('-I%s/gcc/libgo/runtime' % TINYGO)
- cmd.append('-I%s/ports/%s' % (TINYGO, port))
+ cmd.append('-I%s/ports/%s' % (TINYGO, PORT))
  cmd.append('-fplan9-extensions')
 
 def wrapActionCompileGo():
@@ -56,7 +53,7 @@ def wrapActionCompileGo():
  if MCU == 'esp32':
  cmd.append('-mlongcalls')
  cmd.append('-nostdlib')
- cmd.append('-L%s/ports/%s/build' % (TINYGO, port))
+ cmd.append('-L%s/ports/%s/build' % (TINYGO, PORT))
 
 def wrapActionArMerge():
  # Merge multiple object files together
@@ -68,9 +65,11 @@ def wrapActionLink():
  cmd.extend(FLAGS)
  cmd.append('-Wl,--gc-sections')
  cmd.append('-Wno-lto-type-mismatch')
- cmd.append('%s/ports/%s/build/syscall.o' % (TINYGO, port))
- cmd.append('%s/ports/%s/build/os.o' % (TINYGO, port))
- cmd.append('%s/ports/%s/build/libruntime.a' % (TINYGO, port))
+ cmd.append('%s/ports/%s/build/syscall.o' % (TINYGO, PORT))
+ cmd.append('%s/ports/%s/build/os.o' % (TINYGO, PORT))
+ cmd.append('%s/ports/%s/build/libruntime.a' % (TINYGO, PORT))
+ if os.path.exists('%s/ports/%s/build/machine.o' % (TINYGO, PORT)):
+ cmd.append('%s/ports/%s/build/machine.o' % (TINYGO, PORT))
  if MCU == 'esp32':
  #cmd[0] = LD
  SDK = os.environ['ESPIDF']
@@ -92,12 +91,12 @@ def wrapActionLink():
  cmd.append('-lwpa2')
  cmd.append(SDK + '/components/newlib/lib/libc.a')
  cmd.append(SDK + '/components/newlib/lib/libm.a')
- cmd.append(SDK + '/components/' + port + '/libhal.a')
+ cmd.append(SDK + '/components/' + PORT + '/libhal.a')
  cmd.append('-Wl,--end-group')
- cmd.append('-L%s/components/%s/ld' % (SDK, port))
- cmd.append('-L%s/components/%s/lib' % (SDK, port))
+ cmd.append('-L%s/components/%s/ld' % (SDK, PORT))
+ cmd.append('-L%s/components/%s/lib' % (SDK, PORT))
  cmd.append('-T')
- cmd.append('%s/ports/%s/build/esp32_out.ld' % (TINYGO, port))
+ cmd.append('%s/ports/%s/build/esp32_out.ld' % (TINYGO, PORT))
  cmd.append('-T')
  cmd.append('esp32.common.ld')
  cmd.append('-T')