Improvements for stm32wle targets :

- board/stm32: Add STM32 Nucleo WL55JC board
- stm32/stm32wl: Set 48Mhz HSE32/PLL as default Clock, SPI implementation

src/machine/board_lorae5.go

@@ -9,8 +9,8 @@ import (
 )
 
 const (
-	LED1 = PB5
-	LED  = LED1 // Default LED
+	// We assume a LED is connected on PB5
+	LED = PB5 // Default LED
 )
 
 // SubGhz (SPI3)
@@ -46,6 +46,11 @@ var (
 		RxAltFuncSelector: AF7_USART1_2,
 	}
 	DefaultUART = UART0
+
+	// SPI
+	SPI3 = SPI{
+		Bus: stm32.SPI3,
+	}
 )
 
 func init() {

src/machine/board_nucleowl55jc.go

@@ -0,0 +1,72 @@
+//go:build nucleowl55jc
+// +build nucleowl55jc
+
+package machine
+
+import (
+	"device/stm32"
+	"runtime/interrupt"
+)
+
+const (
+	LED_BLUE  = PB15
+	LED_GREEN = PB9
+	LED_RED   = PB11
+	LED       = LED_RED
+
+	BTN1   = PA0
+	BTN2   = PA1
+	BTN3   = PC6
+	BUTTON = BTN1
+
+	// SubGhz (SPI3)
+	SPI0_NSS_PIN = PA4
+	SPI0_SCK_PIN = PA5
+	SPI0_SDO_PIN = PA6
+	SPI0_SDI_PIN = PA7
+
+	//MCU USART1
+	UART1_TX_PIN = PB6
+	UART1_RX_PIN = PB7
+
+	//MCU USART2
+	UART2_RX_PIN = PA3
+	UART2_TX_PIN = PA2
+
+	// DEFAULT USART
+	UART_RX_PIN = UART2_RX_PIN
+	UART_TX_PIN = UART2_TX_PIN
+)
+
+var (
+	// STM32 UART2 is connected to the embedded STLINKV3 Virtual Com Port
+	UART0  = &_UART0
+	_UART0 = UART{
+		Buffer:            NewRingBuffer(),
+		Bus:               stm32.USART2,
+		TxAltFuncSelector: 7,
+		RxAltFuncSelector: 7,
+	}
+
+	// UART1 is free
+	UART1  = &_UART1
+	_UART1 = UART{
+		Buffer:            NewRingBuffer(),
+		Bus:               stm32.USART1,
+		TxAltFuncSelector: 7,
+		RxAltFuncSelector: 7,
+	}
+
+	DefaultUART = UART0
+
+	// SPI
+	SPI3 = SPI{
+		Bus: stm32.SPI3,
+	}
+)
+
+func init() {
+	// Enable UARTs Interrupts
+	UART0.Interrupt = interrupt.New(stm32.IRQ_USART2, _UART0.handleInterrupt)
+	UART1.Interrupt = interrupt.New(stm32.IRQ_USART1, _UART1.handleInterrupt)
+}

src/machine/machine_stm32_spi.go

@@ -1,5 +1,5 @@
-//go:build stm32 && !stm32f7x2 && !stm32l5x2 && !stm32wle5
-// +build stm32,!stm32f7x2,!stm32l5x2,!stm32wle5
+//go:build stm32 && !stm32f7x2 && !stm32l5x2
+// +build stm32,!stm32f7x2,!stm32l5x2
 
 package machine
 

src/machine/machine_stm32wle5.go

@@ -7,6 +7,7 @@ package machine
 
 import (
 	"device/stm32"
+	"math/bits"
 	"runtime/interrupt"
 	"runtime/volatile"
 	"unsafe"
@@ -28,12 +29,15 @@ const (
 	AF15_EVENTOUT          = 15
 )
 
-func CPUFrequency() uint32 {
-	return 4e6
-}
+const (
+	SYSCLK        = 48e6
+	APB1_TIM_FREQ = SYSCLK
+	APB2_TIM_FREQ = SYSCLK
+)
 
-const APB1_TIM_FREQ = 4e6
-const APB2_TIM_FREQ = 4e6
+func CPUFrequency() uint32 {
+	return SYSCLK
+}
 
 const (
 	PA0  = portA + 0
@@ -221,6 +225,64 @@ func (p Pin) registerInterrupt() interrupt.Interrupt {
 	return interrupt.Interrupt{}
 }
 
+// -- SPI ----------------------------------------------------------------------
+
+type SPI struct {
+	Bus             *stm32.SPI_Type
+	AltFuncSelector uint8
+}
+
+func (spi SPI) config8Bits() {
+	// Set rx threshold to 8-bits, so RXNE flag is set for 1 byte
+	// (common STM32 SPI implementation does 8-bit transfers only)
+	spi.Bus.CR2.SetBits(stm32.SPI_CR2_FRXTH)
+}
+
+func (spi SPI) configurePins(config SPIConfig) {
+	config.SCK.ConfigureAltFunc(PinConfig{Mode: PinModeSPICLK}, spi.AltFuncSelector)
+	config.SDO.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDO}, spi.AltFuncSelector)
+	config.SDI.ConfigureAltFunc(PinConfig{Mode: PinModeSPISDI}, spi.AltFuncSelector)
+}
+
+func (spi SPI) getBaudRate(config SPIConfig) uint32 {
+	var clock uint32
+
+	// We keep this switch and separate management of SPI Clocks
+	// for future improvement of system/bus clocks and prescalers
+	switch spi.Bus {
+	case stm32.SPI1:
+		clock = CPUFrequency()
+	case stm32.SPI2, stm32.SPI3:
+		clock = CPUFrequency()
+	}
+
+	// limit requested frequency to bus frequency and min frequency (DIV256)
+	freq := config.Frequency
+	if min := clock / 256; freq < min {
+		freq = min
+	} else if freq > clock {
+		freq = clock
+	}
+
+	// calculate the exact clock divisor (freq=clock/div -> div=clock/freq).
+	// truncation is fine, since it produces a less-than-or-equal divisor, and
+	// thus a greater-than-or-equal frequency.
+	// divisors only come in consecutive powers of 2, so we can use log2 (or,
+	// equivalently, bits.Len - 1) to convert to respective enum value.
+	div := bits.Len32(clock/freq) - 1
+
+	// but DIV1 (2^0) is not permitted, as the least divisor is DIV2 (2^1), so
+	// subtract 1 from the log2 value, keeping a lower bound of 0
+	if div < 0 {
+		div = 0
+	} else if div > 0 {
+		div--
+	}
+
+	// finally, shift the enumerated value into position for SPI CR1
+	return uint32(div) << stm32.SPI_CR1_BR_Pos
+}
+
 //---------- UART related code
 
 // Configure the UART.

src/machine/spi.go

@@ -1,5 +1,5 @@
-//go:build !baremetal || (stm32 && !stm32f7x2 && !stm32l5x2 && !stm32wle5) || fe310 || k210 || atmega
-// +build !baremetal stm32,!stm32f7x2,!stm32l5x2,!stm32wle5 fe310 k210 atmega
+//go:build !baremetal || (stm32 && !stm32f7x2 && !stm32l5x2) || fe310 || k210 || atmega
+// +build !baremetal stm32,!stm32f7x2,!stm32l5x2 fe310 k210 atmega
 
 package machine