Separate PLL config for RP2040 and RP2350

src/machine/machine_rp2_2040.go

@@ -113,6 +113,19 @@ const (
 	fnXIP pinFunc = 0
 )
 
+// System clock configuration
+const (
+	pllSysFreq uint32 = 125*MHz
+	pllSysVcoFreq = 1500*MHz
+	pllSysPostDiv1 = 6
+	pllSysPostDiv2 = 2
+
+	pllUSBFreq uint32 = 48*MHz
+	pllUSBVcoFreq = 480*MHz
+	pllUSBPostDiv1 = 5
+	pllUSBPostDiv2 = 2
+)
+
 // Configure configures the gpio pin as per mode.
 func (p Pin) Configure(config PinConfig) {
 	if p == NoPin {
@@ -184,7 +197,7 @@ func (clks *clocksType) initRTC() {
 	crtc := clks.clock(clkRTC)
 	crtc.configure(0, // No GLMUX
 		rp.CLOCKS_CLK_RTC_CTRL_AUXSRC_CLKSRC_PLL_USB,
-		48*MHz,
+		pllUSBFreq,
 		46875)
 }
 

src/machine/machine_rp2_2350.go

@@ -120,6 +120,20 @@ const (
 	fnNULL    pinFunc = 0x1f
 )
 
+// System clock configuration
+// Note that VcoFreq, PostDiv1, and PostDiv2 must be manually calculated to achive desired output frequency.
+const (
+	pllSysFreq uint32 = 150*MHz
+	pllSysVcoFreq = 1500*MHz
+	pllSysPostDiv1 = 5
+	pllSysPostDiv2 = 2
+
+	pllUSBFreq uint32 = 48*MHz
+	pllUSBVcoFreq = 480*MHz
+	pllUSBPostDiv1 = 5
+	pllUSBPostDiv2 = 2
+)
+
 // Configure configures the gpio pin as per mode.
 func (p Pin) Configure(config PinConfig) {
 	if p == NoPin {

src/machine/machine_rp2_clocks.go

@@ -10,13 +10,13 @@ import (
 )
 
 func CPUFrequency() uint32 {
-	return 125 * MHz
+	return pllSysFreq
 }
 
 // Returns the period of a clock cycle for the raspberry pi pico in nanoseconds.
 // Used in PWM API.
 func cpuPeriod() uint32 {
-	return 1e9 / CPUFrequency()
+	return uint32(1e9) / pllSysFreq // TODO: Discards remainder
 }
 
 // clockIndex identifies a hardware clock
@@ -168,9 +168,9 @@ func (clks *clocksType) init() {
 	// Configure PLLs
 	//                   REF     FBDIV VCO            POSTDIV
 	// pllSys: 12 / 1 = 12MHz * 125 = 1500MHZ / 6 / 2 = 125MHz
+	pllSys.init(1, pllSysVcoFreq, pllSysPostDiv1, pllSysPostDiv2)
 	// pllUSB: 12 / 1 = 12MHz * 40  = 480 MHz / 5 / 2 =  48MHz
-	pllSys.init(1, 1500*MHz, 6, 2)
-	pllUSB.init(1, 480*MHz, 5, 2)
+	pllUSB.init(1, pllUSBVcoFreq, pllUSBPostDiv1, pllUSBPostDiv2)
 
 	// Configure clocks
 	// clkRef = xosc (12MHz) / 1 = 12MHz
@@ -180,26 +180,26 @@ func (clks *clocksType) init() {
 		12*MHz,
 		12*MHz)
 
-	// clkSys = pllSys (125MHz) / 1 = 125MHz
+	// clkSys = pllSys (pllSysFreq) / 1 = pllSysFreq
 	csys := clks.clock(clkSys)
 	csys.configure(rp.CLOCKS_CLK_SYS_CTRL_SRC_CLKSRC_CLK_SYS_AUX,
 		rp.CLOCKS_CLK_SYS_CTRL_AUXSRC_CLKSRC_PLL_SYS,
-		125*MHz,
-		125*MHz)
+		pllSysFreq,
+		pllSysFreq)
 
-	// clkUSB = pllUSB (48MHz) / 1 = 48MHz
+	// clkUSB = pllUSB (pllUSBFreq) / 1 = 48MHz
 	cusb := clks.clock(clkUSB)
 	cusb.configure(0, // No GLMUX
 		rp.CLOCKS_CLK_USB_CTRL_AUXSRC_CLKSRC_PLL_USB,
-		48*MHz,
-		48*MHz)
+		pllUSBFreq,
+		pllUSBFreq)
 
-	// clkADC = pllUSB (48MHZ) / 1 = 48MHz
+	// clkADC = pllUSB (pllUSBFreq) / 1 = 48MHz
 	cadc := clks.clock(clkADC)
 	cadc.configure(0, // No GLMUX
 		rp.CLOCKS_CLK_ADC_CTRL_AUXSRC_CLKSRC_PLL_USB,
-		48*MHz,
-		48*MHz)
+		pllUSBFreq,
+		pllUSBFreq)
 
 	clks.initRTC()
 
@@ -209,8 +209,8 @@ func (clks *clocksType) init() {
 	cperi := clks.clock(clkPeri)
 	cperi.configure(0,
 		rp.CLOCKS_CLK_PERI_CTRL_AUXSRC_CLK_SYS,
-		125*MHz,
-		125*MHz)
+		pllSysFreq,
+		pllSysFreq)
 
 	clks.initTicks()
 }

src/machine/machine_rp2_i2c.go

@@ -162,7 +162,7 @@ func (i2c *I2C) SetBaudRate(br uint32) error {
 	}
 
 	// I2C is synchronous design that runs from clk_sys
-	freqin := CPUFrequency()
+	freqin := pllSysFreq
 
 	// TODO there are some subtleties to I2C timing which we are completely ignoring here
 	period := (freqin + br/2) / br

src/machine/machine_rp2_spi.go

@@ -104,7 +104,7 @@ func (spi SPI) Transfer(w byte) (byte, error) {
 }
 
 func (spi SPI) SetBaudRate(br uint32) error {
-	const freqin uint32 = 125 * MHz
+	const freqin uint32 = pllSysFreq
 	const maxBaud uint32 = 66.5 * MHz // max output frequency is 66.5MHz on rp2040. see Note page 527.
 	// Find smallest prescale value which puts output frequency in range of
 	// post-divide. Prescale is an even number from 2 to 254 inclusive.
@@ -130,7 +130,7 @@ func (spi SPI) SetBaudRate(br uint32) error {
 }
 
 func (spi SPI) GetBaudRate() uint32 {
-	const freqin uint32 = 125 * MHz
+	const freqin uint32 = pllSysFreq
 	prescale := spi.Bus.SSPCPSR.Get()
 	postdiv := ((spi.Bus.SSPCR0.Get() & rp.SPI0_SSPCR0_SCR_Msk) >> rp.SPI0_SSPCR0_SCR_Pos) + 1
 	return freqin / (prescale * postdiv)

src/machine/machine_rp2_uart.go

@@ -75,7 +75,7 @@ func (uart *UART) Configure(config UARTConfig) error {
 
 // SetBaudRate sets the baudrate to be used for the UART.
 func (uart *UART) SetBaudRate(br uint32) {
-	div := 8 * 125 * MHz / br
+	div := 8 * pllSysFreq / br
 
 	ibrd := div >> 7
 	var fbrd uint32