machine/stm32f4: refactor common code and add new build tag stm32f4 (#1332)

* machine/STM32F4: break out STM32F4 machine with new build tag

6 files changed, 246 insertions, 171 deletions

diff --git a/src/machine/board_stm32.go b/src/machine/board_stm32.go
index 8dbea217e..7153be860 100644
--- a/src/machine/board_stm32.go
+++ b/src/machine/board_stm32.go
@@ -1,16 +1,5 @@
-// +build bluepill nucleof103rb stm32f4disco
+// +build bluepill nucleof103rb stm32f4
 
 package machine
 
 // Peripheral abstraction layer for the stm32.
-
-const (
-	portA Pin = iota * 16
-	portB
-	portC
-	portD
-	portE
-	portF
-	portG
-	portH
-)
diff --git a/src/machine/board_stm32f4disco.go b/src/machine/board_stm32f4disco.go
index 5367b66c4..20e37a32c 100644
--- a/src/machine/board_stm32f4disco.go
+++ b/src/machine/board_stm32f4disco.go
@@ -8,96 +8,6 @@ import (
 )
 
 const (
-	PA0  = portA + 0
-	PA1  = portA + 1
-	PA2  = portA + 2
-	PA3  = portA + 3
-	PA4  = portA + 4
-	PA5  = portA + 5
-	PA6  = portA + 6
-	PA7  = portA + 7
-	PA8  = portA + 8
-	PA9  = portA + 9
-	PA10 = portA + 10
-	PA11 = portA + 11
-	PA12 = portA + 12
-	PA13 = portA + 13
-	PA14 = portA + 14
-	PA15 = portA + 15
-
-	PB0  = portB + 0
-	PB1  = portB + 1
-	PB2  = portB + 2
-	PB3  = portB + 3
-	PB4  = portB + 4
-	PB5  = portB + 5
-	PB6  = portB + 6
-	PB7  = portB + 7
-	PB8  = portB + 8
-	PB9  = portB + 9
-	PB10 = portB + 10
-	PB11 = portB + 11
-	PB12 = portB + 12
-	PB13 = portB + 13
-	PB14 = portB + 14
-	PB15 = portB + 15
-
-	PC0  = portC + 0
-	PC1  = portC + 1
-	PC2  = portC + 2
-	PC3  = portC + 3
-	PC4  = portC + 4
-	PC5  = portC + 5
-	PC6  = portC + 6
-	PC7  = portC + 7
-	PC8  = portC + 8
-	PC9  = portC + 9
-	PC10 = portC + 10
-	PC11 = portC + 11
-	PC12 = portC + 12
-	PC13 = portC + 13
-	PC14 = portC + 14
-	PC15 = portC + 15
-
-	PD0  = portD + 0
-	PD1  = portD + 1
-	PD2  = portD + 2
-	PD3  = portD + 3
-	PD4  = portD + 4
-	PD5  = portD + 5
-	PD6  = portD + 6
-	PD7  = portD + 7
-	PD8  = portD + 8
-	PD9  = portD + 9
-	PD10 = portD + 10
-	PD11 = portD + 11
-	PD12 = portD + 12
-	PD13 = portD + 13
-	PD14 = portD + 14
-	PD15 = portD + 15
-
-	PE0  = portE + 0
-	PE1  = portE + 1
-	PE2  = portE + 2
-	PE3  = portE + 3
-	PE4  = portE + 4
-	PE5  = portE + 5
-	PE6  = portE + 6
-	PE7  = portE + 7
-	PE8  = portE + 8
-	PE9  = portE + 9
-	PE10 = portE + 10
-	PE11 = portE + 11
-	PE12 = portE + 12
-	PE13 = portE + 13
-	PE14 = portE + 14
-	PE15 = portE + 15
-
-	PH0 = portH + 0
-	PH1 = portH + 1
-)
-
-const (
 	LED         = LED_BUILTIN
 	LED1        = LED_GREEN
 	LED2        = LED_ORANGE
diff --git a/src/machine/i2c.go b/src/machine/i2c.go
index 3bab81d0d..b46506063 100644
--- a/src/machine/i2c.go
+++ b/src/machine/i2c.go
@@ -1,4 +1,4 @@
-// +build avr nrf sam stm32,!stm32f4disco fe310 k210
+// +build avr nrf sam stm32,!stm32f4 fe310 k210
 
 package machine
 
diff --git a/src/machine/machine_stm32.go b/src/machine/machine_stm32.go
index b1ee97aab..8ef5fed7e 100644
--- a/src/machine/machine_stm32.go
+++ b/src/machine/machine_stm32.go
@@ -4,6 +4,19 @@ package machine
 
 // Peripheral abstraction layer for the stm32.
 
+const (
+	portA Pin = iota * 16
+	portB
+	portC
+	portD
+	portE
+	portF
+	portG
+	portH
+	portI
+	portJ
+)
+
 type PinMode uint8
 
 // Peripheral operations sequence:
diff --git a/src/machine/machine_stm32f4.go b/src/machine/machine_stm32f4.go
new file mode 100644
index 000000000..a0b00a811
--- /dev/null
+++ b/src/machine/machine_stm32f4.go
@@ -0,0 +1,229 @@
+// +build stm32f4
+
+package machine
+
+// Peripheral abstraction layer for the stm32f4
+
+import (
+	"device/stm32"
+	"unsafe"
+)
+
+const (
+	PA0  = portA + 0
+	PA1  = portA + 1
+	PA2  = portA + 2
+	PA3  = portA + 3
+	PA4  = portA + 4
+	PA5  = portA + 5
+	PA6  = portA + 6
+	PA7  = portA + 7
+	PA8  = portA + 8
+	PA9  = portA + 9
+	PA10 = portA + 10
+	PA11 = portA + 11
+	PA12 = portA + 12
+	PA13 = portA + 13
+	PA14 = portA + 14
+	PA15 = portA + 15
+
+	PB0  = portB + 0
+	PB1  = portB + 1
+	PB2  = portB + 2
+	PB3  = portB + 3
+	PB4  = portB + 4
+	PB5  = portB + 5
+	PB6  = portB + 6
+	PB7  = portB + 7
+	PB8  = portB + 8
+	PB9  = portB + 9
+	PB10 = portB + 10
+	PB11 = portB + 11
+	PB12 = portB + 12
+	PB13 = portB + 13
+	PB14 = portB + 14
+	PB15 = portB + 15
+
+	PC0  = portC + 0
+	PC1  = portC + 1
+	PC2  = portC + 2
+	PC3  = portC + 3
+	PC4  = portC + 4
+	PC5  = portC + 5
+	PC6  = portC + 6
+	PC7  = portC + 7
+	PC8  = portC + 8
+	PC9  = portC + 9
+	PC10 = portC + 10
+	PC11 = portC + 11
+	PC12 = portC + 12
+	PC13 = portC + 13
+	PC14 = portC + 14
+	PC15 = portC + 15
+
+	PD0  = portD + 0
+	PD1  = portD + 1
+	PD2  = portD + 2
+	PD3  = portD + 3
+	PD4  = portD + 4
+	PD5  = portD + 5
+	PD6  = portD + 6
+	PD7  = portD + 7
+	PD8  = portD + 8
+	PD9  = portD + 9
+	PD10 = portD + 10
+	PD11 = portD + 11
+	PD12 = portD + 12
+	PD13 = portD + 13
+	PD14 = portD + 14
+	PD15 = portD + 15
+
+	PE0  = portE + 0
+	PE1  = portE + 1
+	PE2  = portE + 2
+	PE3  = portE + 3
+	PE4  = portE + 4
+	PE5  = portE + 5
+	PE6  = portE + 6
+	PE7  = portE + 7
+	PE8  = portE + 8
+	PE9  = portE + 9
+	PE10 = portE + 10
+	PE11 = portE + 11
+	PE12 = portE + 12
+	PE13 = portE + 13
+	PE14 = portE + 14
+	PE15 = portE + 15
+
+	PH0 = portH + 0
+	PH1 = portH + 1
+)
+
+func (p Pin) getPort() *stm32.GPIO_Type {
+	switch p / 16 {
+	case 0:
+		return stm32.GPIOA
+	case 1:
+		return stm32.GPIOB
+	case 2:
+		return stm32.GPIOC
+	case 3:
+		return stm32.GPIOD
+	case 4:
+		return stm32.GPIOE
+	case 5:
+		return stm32.GPIOF
+	case 6:
+		return stm32.GPIOG
+	case 7:
+		return stm32.GPIOH
+	case 8:
+		return stm32.GPIOI
+	default:
+		panic("machine: unknown port")
+	}
+}
+
+// enableClock enables the clock for this desired GPIO port.
+func (p Pin) enableClock() {
+	switch p / 16 {
+	case 0:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOAEN)
+	case 1:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOBEN)
+	case 2:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOCEN)
+	case 3:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIODEN)
+	case 4:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOEEN)
+	case 5:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOFEN)
+	case 6:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOGEN)
+	case 7:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOHEN)
+	case 8:
+		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOIEN)
+	default:
+		panic("machine: unknown port")
+	}
+}
+
+// Enable peripheral clock
+func enableAltFuncClock(bus unsafe.Pointer) {
+	switch bus {
+	case unsafe.Pointer(stm32.DAC): // DAC interface clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_DACEN)
+	case unsafe.Pointer(stm32.PWR): // Power interface clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_PWREN)
+	case unsafe.Pointer(stm32.CAN2): // CAN 2 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_CAN2EN)
+	case unsafe.Pointer(stm32.CAN1): // CAN 1 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_CAN1EN)
+	case unsafe.Pointer(stm32.I2C3): // I2C3 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_I2C3EN)
+	case unsafe.Pointer(stm32.I2C2): // I2C2 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_I2C2EN)
+	case unsafe.Pointer(stm32.I2C1): // I2C1 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_I2C1EN)
+	case unsafe.Pointer(stm32.UART5): // UART5 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_UART5EN)
+	case unsafe.Pointer(stm32.UART4): // UART4 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_UART4EN)
+	case unsafe.Pointer(stm32.USART3): // USART3 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_USART3EN)
+	case unsafe.Pointer(stm32.USART2): // USART2 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_USART2EN)
+	case unsafe.Pointer(stm32.SPI3): // SPI3 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_SPI3EN)
+	case unsafe.Pointer(stm32.SPI2): // SPI2 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_SPI2EN)
+	case unsafe.Pointer(stm32.WWDG): // Window watchdog clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_WWDGEN)
+	case unsafe.Pointer(stm32.TIM14): // TIM14 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM14EN)
+	case unsafe.Pointer(stm32.TIM13): // TIM13 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM13EN)
+	case unsafe.Pointer(stm32.TIM12): // TIM12 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM12EN)
+	case unsafe.Pointer(stm32.TIM7): // TIM7 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM7EN)
+	case unsafe.Pointer(stm32.TIM6): // TIM6 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM6EN)
+	case unsafe.Pointer(stm32.TIM5): // TIM5 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM5EN)
+	case unsafe.Pointer(stm32.TIM4): // TIM4 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM4EN)
+	case unsafe.Pointer(stm32.TIM3): // TIM3 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM3EN)
+	case unsafe.Pointer(stm32.TIM2): // TIM2 clock enable
+		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_TIM2EN)
+	case unsafe.Pointer(stm32.TIM11): // TIM11 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM11EN)
+	case unsafe.Pointer(stm32.TIM10): // TIM10 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM10EN)
+	case unsafe.Pointer(stm32.TIM9): // TIM9 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM9EN)
+	case unsafe.Pointer(stm32.SYSCFG): // System configuration controller clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SYSCFGEN)
+	case unsafe.Pointer(stm32.SPI1): // SPI1 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SPI1EN)
+	case unsafe.Pointer(stm32.SDIO): // SDIO clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SDIOEN)
+	case unsafe.Pointer(stm32.ADC3): // ADC3 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_ADC3EN)
+	case unsafe.Pointer(stm32.ADC2): // ADC2 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_ADC2EN)
+	case unsafe.Pointer(stm32.ADC1): // ADC1 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_ADC1EN)
+	case unsafe.Pointer(stm32.USART6): // USART6 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_USART6EN)
+	case unsafe.Pointer(stm32.USART1): // USART1 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_USART1EN)
+	case unsafe.Pointer(stm32.TIM8): // TIM8 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM8EN)
+	case unsafe.Pointer(stm32.TIM1): // TIM1 clock enable
+		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_TIM1EN)
+	}
+}
diff --git a/src/machine/machine_stm32f407.go b/src/machine/machine_stm32f407.go
index 16d1e10bf..232b8e3d2 100644
--- a/src/machine/machine_stm32f407.go
+++ b/src/machine/machine_stm32f407.go
@@ -1,84 +1,18 @@
-// +build stm32,stm32f407
+// +build stm32f407
 
 package machine
 
-// Peripheral abstraction layer for the stm32f4(07)
+// Peripheral abstraction layer for the stm32f407
 
 import (
 	"device/stm32"
 	"runtime/interrupt"
-	"unsafe"
 )
 
 func CPUFrequency() uint32 {
 	return 168000000
 }
 
-func (p Pin) getPort() *stm32.GPIO_Type {
-	switch p / 16 {
-	case 0:
-		return stm32.GPIOA
-	case 1:
-		return stm32.GPIOB
-	case 2:
-		return stm32.GPIOC
-	case 3:
-		return stm32.GPIOD
-	case 4:
-		return stm32.GPIOE
-	case 5:
-		return stm32.GPIOF
-	case 6:
-		return stm32.GPIOG
-	case 7:
-		return stm32.GPIOH
-	case 8:
-		return stm32.GPIOI
-	default:
-		panic("machine: unknown port")
-	}
-}
-
-// enableClock enables the clock for this desired GPIO port.
-func (p Pin) enableClock() {
-	switch p / 16 {
-	case 0:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOAEN)
-	case 1:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOBEN)
-	case 2:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOCEN)
-	case 3:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIODEN)
-	case 4:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOEEN)
-	case 5:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOFEN)
-	case 6:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOGEN)
-	case 7:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOHEN)
-	case 8:
-		stm32.RCC.AHB1ENR.SetBits(stm32.RCC_AHB1ENR_GPIOIEN)
-	default:
-		panic("machine: unknown port")
-	}
-}
-
-// Enable peripheral clock
-func enableAltFuncClock(bus unsafe.Pointer) {
-	switch bus {
-	case unsafe.Pointer(stm32.USART1):
-		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_USART1EN)
-	case unsafe.Pointer(stm32.USART2):
-		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_USART2EN)
-	case unsafe.Pointer(stm32.I2C1):
-		stm32.RCC.APB1ENR.SetBits(stm32.RCC_APB1ENR_I2C1EN)
-	case unsafe.Pointer(stm32.SPI1):
-		stm32.RCC.APB2ENR.SetBits(stm32.RCC_APB2ENR_SPI1EN)
-	}
-}
-
 //---------- UART related types and code
 
 // UART representation