Viable NXP/Teensy support

- Fix UART & putChar
- Timer-based sleep
- Enable systick in abort
- Buffered, interrupt-based UART TX
- Use the new interrupt API and fix sleepTicks
- Make pins behave more like other boards
- Use the MCU's UART numbering
- Allow interrupts to wake the scheduler (#1214)
This commit is contained in:
Ethan Reesor
2020-02-23 20:09:44 -06:00
committed by Ron Evans
parent 59218cd784
commit 4750635a20
11 changed files with 728 additions and 456 deletions
+49 -165
View File
@@ -35,53 +35,41 @@ import (
"device/arm"
"device/nxp"
"machine"
"runtime/volatile"
)
const (
WDOG_UNLOCK_SEQ1 = 0xC520
WDOG_UNLOCK_SEQ2 = 0xD928
watchdogUnlockSequence1 = 0xC520
watchdogUnlockSequence2 = 0xD928
DEFAULT_FTM_MOD = 61440 - 1
DEFAULT_FTM_PRESCALE = 1
_DEFAULT_FTM_MOD = 61440 - 1
_DEFAULT_FTM_PRESCALE = 1
)
var (
SIM_SOPT2_IRC48SEL = nxp.SIM_SOPT2_PLLFLLSEL(3)
SMC_PMCTRL_HSRUN = nxp.SMC_PMCTRL_RUNM(3)
SMC_PMSTAT_HSRUN = nxp.SMC_PMSTAT_PMSTAT(0x80)
const (
_SIM_SOPT2_IRC48SEL = 3 << nxp.SIM_SOPT2_PLLFLLSEL_Pos
_SMC_PMCTRL_HSRUN = 3 << nxp.SMC_PMCTRL_RUNM_Pos
_SMC_PMSTAT_HSRUN = 0x80 << nxp.SMC_PMSTAT_PMSTAT_Pos
)
var bootMsg = []byte("\r\n\r\nStartup complete, running main\r\n\r\n")
//go:section .resetHandler
//go:export Reset_Handler
func main() {
initSystem()
arm.Asm("CPSIE i")
initInternal()
startupLateHook()
initAll()
machine.UART1.Configure(machine.UARTConfig{BaudRate: 115200})
for _, c := range bootMsg {
for !machine.UART1.S1.HasBits(nxp.UART_S1_TDRE) {
}
machine.UART1.D.Set(c)
}
callMain()
run()
abort()
}
// ported ResetHandler from mk20dx128.c from teensy3 core libraries
//go:noinline
func initSystem() {
nxp.WDOG.UNLOCK.Set(WDOG_UNLOCK_SEQ1)
nxp.WDOG.UNLOCK.Set(WDOG_UNLOCK_SEQ2)
// from: ResetHandler
nxp.WDOG.UNLOCK.Set(watchdogUnlockSequence1)
nxp.WDOG.UNLOCK.Set(watchdogUnlockSequence2)
arm.Asm("nop")
arm.Asm("nop")
startupEarlyHook()
// TODO: hook for overriding? 'startupEarlyHook'
nxp.WDOG.STCTRLH.Set(nxp.WDOG_STCTRLH_ALLOWUPDATE)
// enable clocks to always-used peripherals
nxp.SIM.SCGC3.Set(nxp.SIM_SCGC3_ADC1 | nxp.SIM_SCGC3_FTM2 | nxp.SIM_SCGC3_FTM3)
@@ -117,9 +105,9 @@ func initSystem() {
// enable capacitors for crystal
nxp.OSC.CR.Set(nxp.OSC_CR_SC8P | nxp.OSC_CR_SC2P | nxp.OSC_CR_ERCLKEN)
// enable osc, 8-32 MHz range, low power mode
nxp.MCG.C2.Set(uint8(nxp.MCG_C2_RANGE(2) | nxp.MCG_C2_EREFS))
nxp.MCG.C2.Set(uint8((2 << nxp.MCG_C2_RANGE_Pos) | nxp.MCG_C2_EREFS))
// switch to crystal as clock source, FLL input = 16 MHz / 512
nxp.MCG.C1.Set(uint8(nxp.MCG_C1_CLKS(2) | nxp.MCG_C1_FRDIV(4)))
nxp.MCG.C1.Set(uint8((2 << nxp.MCG_C1_CLKS_Pos) | (4 << nxp.MCG_C1_FRDIV_Pos)))
// wait for crystal oscillator to begin
for !nxp.MCG.S.HasBits(nxp.MCG_S_OSCINIT0) {
}
@@ -127,7 +115,7 @@ func initSystem() {
for nxp.MCG.S.HasBits(nxp.MCG_S_IREFST) {
}
// wait for MCGOUT to use oscillator
for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != nxp.MCG_S_CLKST(2) {
for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != (2 << nxp.MCG_S_CLKST_Pos) {
}
// now in FBE mode
@@ -137,11 +125,11 @@ func initSystem() {
// C6[PLLS] bit is written to 0
// C2[LP] is written to 0
// we need faster than the crystal, turn on the PLL (F_CPU > 120000000)
nxp.SMC.PMCTRL.Set(SMC_PMCTRL_HSRUN) // enter HSRUN mode
for nxp.SMC.PMSTAT.Get() != SMC_PMSTAT_HSRUN {
nxp.SMC.PMCTRL.Set(_SMC_PMCTRL_HSRUN) // enter HSRUN mode
for nxp.SMC.PMSTAT.Get() != _SMC_PMSTAT_HSRUN {
} // wait for HSRUN
nxp.MCG.C5.Set(nxp.MCG_C5_PRDIV(1))
nxp.MCG.C6.Set(nxp.MCG_C6_PLLS | nxp.MCG_C6_VDIV(29))
nxp.MCG.C5.Set((1 << nxp.MCG_C5_PRDIV_Pos))
nxp.MCG.C6.Set(nxp.MCG_C6_PLLS | (29 << nxp.MCG_C6_VDIV_Pos))
// wait for PLL to start using xtal as its input
for !nxp.MCG.S.HasBits(nxp.MCG_S_PLLST) {
@@ -153,18 +141,18 @@ func initSystem() {
// now program the clock dividers
// config divisors: 180 MHz core, 60 MHz bus, 25.7 MHz flash, USB = IRC48M
nxp.SIM.CLKDIV1.Set(nxp.SIM_CLKDIV1_OUTDIV1(0) | nxp.SIM_CLKDIV1_OUTDIV2(2) | nxp.SIM_CLKDIV1_OUTDIV4(6))
nxp.SIM.CLKDIV2.Set(nxp.SIM_CLKDIV2_USBDIV(0))
nxp.SIM.CLKDIV1.Set((0 << nxp.SIM_CLKDIV1_OUTDIV1_Pos) | (2 << nxp.SIM_CLKDIV1_OUTDIV2_Pos) | (0 << nxp.SIM_CLKDIV1_OUTDIV1_Pos) | (6 << nxp.SIM_CLKDIV1_OUTDIV4_Pos))
nxp.SIM.CLKDIV2.Set((0 << nxp.SIM_CLKDIV2_USBDIV_Pos))
// switch to PLL as clock source, FLL input = 16 MHz / 512
nxp.MCG.C1.Set(nxp.MCG_C1_CLKS(0) | nxp.MCG_C1_FRDIV(4))
nxp.MCG.C1.Set((0 << nxp.MCG_C1_CLKS_Pos) | (4 << nxp.MCG_C1_FRDIV_Pos))
// wait for PLL clock to be used
for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != nxp.MCG_S_CLKST(3) {
for (nxp.MCG.S.Get() & nxp.MCG_S_CLKST_Msk) != (3 << nxp.MCG_S_CLKST_Pos) {
}
// now we're in PEE mode
// trace is CPU clock, CLKOUT=OSCERCLK0
// USB uses IRC48
nxp.SIM.SOPT2.Set(nxp.SIM_SOPT2_USBSRC | SIM_SOPT2_IRC48SEL | nxp.SIM_SOPT2_TRACECLKSEL | nxp.SIM_SOPT2_CLKOUTSEL(6))
nxp.SIM.SOPT2.Set(nxp.SIM_SOPT2_USBSRC | _SIM_SOPT2_IRC48SEL | nxp.SIM_SOPT2_TRACECLKSEL | (6 << nxp.SIM_SOPT2_CLKOUTSEL_Pos))
// If the RTC oscillator isn't enabled, get it started. For Teensy 3.6
// we don't do this early. See comment above about slow rising power.
@@ -174,23 +162,19 @@ func initSystem() {
}
// initialize the SysTick counter
nxp.SysTick.RVR.Set((machine.CPUFrequency() / 1000) - 1)
nxp.SysTick.CVR.Set(0)
nxp.SysTick.CSR.Set(nxp.SysTick_CSR_CLKSOURCE | nxp.SysTick_CSR_TICKINT | nxp.SysTick_CSR_ENABLE)
nxp.SystemControl.SHPR3.Set(0x20200000) // Systick = priority 32
initSysTick()
}
// ported _init_Teensyduino_internal_ from pins_teensy.c from teensy3 core libraries
//go:noinline
func initInternal() {
arm.EnableIRQ(nxp.IRQ_PORTA)
arm.EnableIRQ(nxp.IRQ_PORTB)
arm.EnableIRQ(nxp.IRQ_PORTC)
arm.EnableIRQ(nxp.IRQ_PORTD)
arm.EnableIRQ(nxp.IRQ_PORTE)
// from: _init_Teensyduino_internal_
// arm.EnableIRQ(nxp.IRQ_PORTA)
// arm.EnableIRQ(nxp.IRQ_PORTB)
// arm.EnableIRQ(nxp.IRQ_PORTC)
// arm.EnableIRQ(nxp.IRQ_PORTD)
// arm.EnableIRQ(nxp.IRQ_PORTE)
nxp.FTM0.CNT.Set(0)
nxp.FTM0.MOD.Set(DEFAULT_FTM_MOD)
nxp.FTM0.MOD.Set(_DEFAULT_FTM_MOD)
nxp.FTM0.C0SC.Set(0x28) // MSnB:MSnA = 10, ELSnB:ELSnA = 10
nxp.FTM0.C1SC.Set(0x28)
nxp.FTM0.C2SC.Set(0x28)
@@ -209,145 +193,45 @@ func initInternal() {
nxp.FTM3.C6SC.Set(0x28)
nxp.FTM3.C7SC.Set(0x28)
nxp.FTM0.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
nxp.FTM0.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
nxp.FTM1.CNT.Set(0)
nxp.FTM1.MOD.Set(DEFAULT_FTM_MOD)
nxp.FTM1.MOD.Set(_DEFAULT_FTM_MOD)
nxp.FTM1.C0SC.Set(0x28)
nxp.FTM1.C1SC.Set(0x28)
nxp.FTM1.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
nxp.FTM1.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
// causes a data bus error for unknown reasons
// nxp.FTM2.CNT.Set(0)
// nxp.FTM2.MOD.Set(DEFAULT_FTM_MOD)
// nxp.FTM2.MOD.Set(_DEFAULT_FTM_MOD)
// nxp.FTM2.C0SC.Set(0x28)
// nxp.FTM2.C1SC.Set(0x28)
// nxp.FTM2.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
// nxp.FTM2.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
nxp.FTM3.CNT.Set(0)
nxp.FTM3.MOD.Set(DEFAULT_FTM_MOD)
nxp.FTM3.MOD.Set(_DEFAULT_FTM_MOD)
nxp.FTM3.C0SC.Set(0x28)
nxp.FTM3.C1SC.Set(0x28)
nxp.FTM3.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(DEFAULT_FTM_PRESCALE))
nxp.FTM3.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (_DEFAULT_FTM_PRESCALE << nxp.FTM_SC_PS_Pos))
nxp.SIM.SCGC2.SetBits(nxp.SIM_SCGC2_TPM1)
nxp.SIM.SOPT2.SetBits(nxp.SIM_SOPT2_TPMSRC(2))
nxp.SIM.SOPT2.SetBits((2 << nxp.SIM_SOPT2_TPMSRC_Pos))
nxp.TPM1.CNT.Set(0)
nxp.TPM1.MOD.Set(32767)
nxp.TPM1.C0SC.Set(0x28)
nxp.TPM1.C1SC.Set(0x28)
nxp.TPM1.SC.Set(nxp.FTM_SC_CLKS(1) | nxp.FTM_SC_PS(0))
nxp.TPM1.SC.Set((1 << nxp.FTM_SC_CLKS_Pos) | (0 << nxp.FTM_SC_PS_Pos))
// configure the low-power timer
// nxp.LPTMR0.CSR.Set(nxp.LPTMR0_CSR_TIE)
// nxp.LPTMR0.PSR.Set(nxp.LPTMR0_PSR_PCS(3) | nxp.LPTMR0_PSR_PRESCALE(1)) // use main (external) clock, divided by 4
// arm.EnableIRQ(nxp.IRQ_LPTMR0)
// configure the sleep timer
initSleepTimer()
// analog_init();
// #if !defined(TEENSY_INIT_USB_DELAY_BEFORE)
// #if TEENSYDUINO >= 142
// #define TEENSY_INIT_USB_DELAY_BEFORE 25
// #else
// #define TEENSY_INIT_USB_DELAY_BEFORE 50
// #endif
// #endif
// #if !defined(TEENSY_INIT_USB_DELAY_AFTER)
// #if TEENSYDUINO >= 142
// #define TEENSY_INIT_USB_DELAY_AFTER 275
// #else
// #define TEENSY_INIT_USB_DELAY_AFTER 350
// #endif
// #endif
// // for background about this startup delay, please see these conversations
// // https://forum.pjrc.com/threads/36606-startup-time-(400ms)?p=113980&viewfull=1#post113980
// // https://forum.pjrc.com/threads/31290-Teensey-3-2-Teensey-Loader-1-24-Issues?p=87273&viewfull=1#post87273
// delay(TEENSY_INIT_USB_DELAY_BEFORE);
// usb_init();
// delay(TEENSY_INIT_USB_DELAY_AFTER);
}
func startupEarlyHook() {
// TODO allow override
// > programs using the watchdog timer or needing to initialize hardware as
// > early as possible can implement startup_early_hook()
nxp.WDOG.STCTRLH.Set(nxp.WDOG_STCTRLH_ALLOWUPDATE)
}
func startupLateHook() {
// TODO allow override
}
func postinit() {}
func putchar(c byte) {
machine.UART1.WriteByte(c)
machine.PutcharUART(&machine.UART0, c)
}
// ???
const asyncScheduler = false
// microseconds per tick
const tickMicros = 1000
// number of ticks since boot
var tickMilliCount volatile.Register32
//go:export SysTick_Handler
func tickHandler() {
tickMilliCount.Set(tickMilliCount.Get() + 1)
}
// ticks are in microseconds
func ticks() timeUnit {
m := arm.DisableInterrupts()
current := nxp.SysTick.CVR.Get()
count := tickMilliCount.Get()
istatus := nxp.SystemControl.ICSR.Get()
arm.EnableInterrupts(m)
if istatus&nxp.SystemControl_ICSR_PENDSTSET != 0 && current > 50 {
count++
}
current = ((machine.CPUFrequency() / tickMicros) - 1) - current
return timeUnit(count*tickMicros + current/(machine.CPUFrequency()/1000000))
}
// sleepTicks spins for a number of microseconds
func sleepTicks(d timeUnit) {
// TODO actually sleep
if d <= 0 {
return
}
start := ticks()
ms := d / 1000
for {
for ticks()-start >= 1000 {
ms--
if ms <= 0 {
return
}
start += 1000
}
arm.Asm("wfi")
}
}
func Sleep(d int64) {
sleepTicks(timeUnit(d))
}
// func abort() {
// for {
// // keep polling some communication while in fault
// // mode, so we don't completely die.
// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_USBOTG) usb_isr();
// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART0) uart0_status_isr();
// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART1) uart1_status_isr();
// if nxp.SIM.SCGC4.HasBits(nxp.SIM_SCGC4_UART2) uart2_status_isr();
// }
// }