tinygo/src/machine/machine_nrf52840_usb.go
2021-02-26 00:32:33 +01:00

531 строка
13 КиБ
Go

// +build nrf52840
package machine
import (
"device/arm"
"device/nrf"
"runtime/interrupt"
"runtime/volatile"
"unsafe"
)
// USBCDC is the USB CDC aka serial over USB interface on the nRF52840
type USBCDC struct {
Buffer *RingBuffer
interrupt interrupt.Interrupt
initcomplete bool
TxIdx volatile.Register8
waitTxc bool
waitTxcRetryCount uint8
sent bool
}
const (
usbcdcTxSizeMask uint8 = 0x3F
usbcdcTxBankMask uint8 = ^usbcdcTxSizeMask
usbcdcTxBank1st uint8 = 0x00
usbcdcTxBank2nd uint8 = usbcdcTxSizeMask + 1
usbcdcTxMaxRetriesAllowed uint8 = 5
)
// Flush flushes buffered data.
func (usbcdc *USBCDC) Flush() error {
if usbLineInfo.lineState > 0 {
idx := usbcdc.TxIdx.Get()
sz := idx & usbcdcTxSizeMask
bk := idx & usbcdcTxBankMask
if 0 < sz {
if usbcdc.waitTxc {
// waiting for the next flush(), because the transmission is not complete
usbcdc.waitTxcRetryCount++
return nil
}
usbcdc.waitTxc = true
usbcdc.waitTxcRetryCount = 0
// set the data
enterCriticalSection()
sendViaEPIn(
usb_CDC_ENDPOINT_IN,
&udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][bk],
int(sz),
)
if bk == usbcdcTxBank1st {
usbcdc.TxIdx.Set(usbcdcTxBank2nd)
} else {
usbcdc.TxIdx.Set(usbcdcTxBank1st)
}
USB.sent = true
}
}
return nil
}
// WriteByte writes a byte of data to the USB CDC interface.
func (usbcdc USBCDC) WriteByte(c byte) error {
// Supposedly to handle problem with Windows USB serial ports?
if usbLineInfo.lineState > 0 {
ok := false
for {
mask := interrupt.Disable()
idx := USB.TxIdx.Get()
if (idx & usbcdcTxSizeMask) < usbcdcTxSizeMask {
udd_ep_in_cache_buffer[usb_CDC_ENDPOINT_IN][idx] = c
USB.TxIdx.Set(idx + 1)
ok = true
}
interrupt.Restore(mask)
if ok {
break
} else if usbcdcTxMaxRetriesAllowed < USB.waitTxcRetryCount {
mask := interrupt.Disable()
USB.waitTxc = false
USB.waitTxcRetryCount = 0
USB.TxIdx.Set(0)
usbLineInfo.lineState = 0
interrupt.Restore(mask)
break
} else {
mask := interrupt.Disable()
if USB.sent {
if USB.waitTxc {
if !easyDMABusy.HasBits(1) {
USB.waitTxc = false
USB.Flush()
}
} else {
USB.Flush()
}
}
interrupt.Restore(mask)
}
}
}
return nil
}
func (usbcdc USBCDC) DTR() bool {
return (usbLineInfo.lineState & usb_CDC_LINESTATE_DTR) > 0
}
func (usbcdc USBCDC) RTS() bool {
return (usbLineInfo.lineState & usb_CDC_LINESTATE_RTS) > 0
}
var (
USB = USBCDC{Buffer: NewRingBuffer()}
usbEndpointDescriptors [8]usbDeviceDescriptor
udd_ep_in_cache_buffer [7][128]uint8
udd_ep_out_cache_buffer [7][128]uint8
sendOnEP0DATADONE struct {
ptr *byte
count int
}
isEndpointHalt = false
isRemoteWakeUpEnabled = false
endPoints = []uint32{usb_ENDPOINT_TYPE_CONTROL,
(usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointIn),
(usb_ENDPOINT_TYPE_BULK | usbEndpointOut),
(usb_ENDPOINT_TYPE_BULK | usbEndpointIn)}
usbConfiguration uint8
usbSetInterface uint8
usbLineInfo = cdcLineInfo{115200, 0x00, 0x00, 0x08, 0x00}
epinen uint32
epouten uint32
easyDMABusy volatile.Register8
epout0data_setlinecoding bool
)
// enterCriticalSection is used to protect access to easyDMA - only one thing
// can be done with it at a time
func enterCriticalSection() {
waitForEasyDMA()
easyDMABusy.SetBits(1)
}
func waitForEasyDMA() {
for easyDMABusy.HasBits(1) {
arm.Asm("wfi")
}
}
func exitCriticalSection() {
easyDMABusy.ClearBits(1)
}
// Configure the USB CDC interface. The config is here for compatibility with the UART interface.
func (usbcdc *USBCDC) Configure(config UARTConfig) {
if usbcdc.initcomplete {
return
}
// Enable IRQ. Make sure this is higher than the SWI2 interrupt handler so
// that it is possible to print to the console from a BLE interrupt. You
// shouldn't generally do that but it is useful for debugging and panic
// logging.
usbcdc.interrupt = interrupt.New(nrf.IRQ_USBD, USB.handleInterrupt)
usbcdc.interrupt.SetPriority(0x40) // interrupt priority 2 (lower number means more important)
usbcdc.interrupt.Enable()
// enable USB
nrf.USBD.ENABLE.Set(1)
// enable interrupt for end of reset and start of frame
nrf.USBD.INTENSET.Set(
nrf.USBD_INTENSET_EPDATA |
nrf.USBD_INTENSET_EP0DATADONE |
nrf.USBD_INTENSET_USBEVENT |
nrf.USBD_INTENSET_SOF |
nrf.USBD_INTENSET_EP0SETUP,
)
nrf.USBD.USBPULLUP.Set(0)
usbcdc.initcomplete = true
}
func (usbcdc *USBCDC) handleInterrupt(interrupt.Interrupt) {
if nrf.USBD.EVENTS_SOF.Get() == 1 {
nrf.USBD.EVENTS_SOF.Set(0)
USB.Flush()
}
// USBD ready event
if nrf.USBD.EVENTS_USBEVENT.Get() == 1 {
nrf.USBD.EVENTS_USBEVENT.Set(0)
if (nrf.USBD.EVENTCAUSE.Get() & nrf.USBD_EVENTCAUSE_READY) > 0 {
// Configure control endpoint
initEndpoint(0, usb_ENDPOINT_TYPE_CONTROL)
// Enable Setup-Received interrupt
nrf.USBD.INTENSET.Set(nrf.USBD_INTENSET_EP0SETUP)
nrf.USBD.USBPULLUP.Set(1)
usbConfiguration = 0
}
nrf.USBD.EVENTCAUSE.Set(0)
}
if nrf.USBD.EVENTS_EP0DATADONE.Get() == 1 {
// done sending packet - either need to send another or enter status stage
nrf.USBD.EVENTS_EP0DATADONE.Set(0)
if epout0data_setlinecoding {
nrf.USBD.EPOUT[0].PTR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_out_cache_buffer[0]))))
nrf.USBD.EPOUT[0].MAXCNT.Set(64)
nrf.USBD.TASKS_STARTEPOUT[0].Set(1)
return
}
if sendOnEP0DATADONE.ptr != nil {
// previous data was too big for one packet, so send a second
sendViaEPIn(
0,
sendOnEP0DATADONE.ptr,
sendOnEP0DATADONE.count,
)
// clear, so we know we're done
sendOnEP0DATADONE.ptr = nil
} else {
// no more data, so set status stage
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
return
}
// Endpoint 0 Setup interrupt
if nrf.USBD.EVENTS_EP0SETUP.Get() == 1 {
// ack setup received
nrf.USBD.EVENTS_EP0SETUP.Set(0)
// parse setup
setup := parseUSBSetupRegisters()
ok := false
if (setup.bmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
// Standard Requests
ok = handleStandardSetup(setup)
} else {
if setup.wIndex == usb_CDC_ACM_INTERFACE {
ok = cdcSetup(setup)
}
}
if !ok {
// Stall endpoint
nrf.USBD.TASKS_EP0STALL.Set(1)
}
}
// Now the actual transfer handlers, ignore endpoint number 0 (setup)
if nrf.USBD.EVENTS_EPDATA.Get() > 0 {
nrf.USBD.EVENTS_EPDATA.Set(0)
epDataStatus := nrf.USBD.EPDATASTATUS.Get()
nrf.USBD.EPDATASTATUS.Set(epDataStatus)
var i uint32
for i = 1; i < uint32(len(endPoints)); i++ {
// Check if endpoint has a pending interrupt
inDataDone := epDataStatus&(nrf.USBD_EPDATASTATUS_EPIN1<<(i-1)) > 0
outDataDone := epDataStatus&(nrf.USBD_EPDATASTATUS_EPOUT1<<(i-1)) > 0
if inDataDone || outDataDone {
switch i {
case usb_CDC_ENDPOINT_OUT:
// setup buffer to receive from host
if outDataDone {
enterCriticalSection()
nrf.USBD.EPOUT[i].PTR.Set(uint32(uintptr(unsafe.Pointer(&udd_ep_out_cache_buffer[i]))))
count := nrf.USBD.SIZE.EPOUT[i].Get()
nrf.USBD.EPOUT[i].MAXCNT.Set(count)
nrf.USBD.TASKS_STARTEPOUT[i].Set(1)
}
case usb_CDC_ENDPOINT_IN: //, usb_CDC_ENDPOINT_ACM:
if inDataDone {
USB.waitTxc = false
exitCriticalSection()
}
}
}
}
}
// ENDEPOUT[n] events
for i := 0; i < len(endPoints); i++ {
if nrf.USBD.EVENTS_ENDEPOUT[i].Get() > 0 {
nrf.USBD.EVENTS_ENDEPOUT[i].Set(0)
if i == 0 && epout0data_setlinecoding {
epout0data_setlinecoding = false
count := int(nrf.USBD.SIZE.EPOUT[0].Get())
if count >= 7 {
parseUSBLineInfo(udd_ep_out_cache_buffer[0][:count])
checkShouldReset()
}
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
if i == usb_CDC_ENDPOINT_OUT {
usbcdc.handleEndpoint(uint32(i))
}
exitCriticalSection()
}
}
}
func parseUSBLineInfo(b []byte) {
usbLineInfo.dwDTERate = uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
usbLineInfo.bCharFormat = b[4]
usbLineInfo.bParityType = b[5]
usbLineInfo.bDataBits = b[6]
}
func parseUSBSetupRegisters() usbSetup {
return usbSetup{
bmRequestType: uint8(nrf.USBD.BMREQUESTTYPE.Get()),
bRequest: uint8(nrf.USBD.BREQUEST.Get()),
wValueL: uint8(nrf.USBD.WVALUEL.Get()),
wValueH: uint8(nrf.USBD.WVALUEH.Get()),
wIndex: uint16((nrf.USBD.WINDEXH.Get() << 8) | nrf.USBD.WINDEXL.Get()),
wLength: uint16(((nrf.USBD.WLENGTHH.Get() & 0xff) << 8) | (nrf.USBD.WLENGTHL.Get() & 0xff)),
}
}
func initEndpoint(ep, config uint32) {
switch config {
case usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointIn:
enableEPIn(ep)
case usb_ENDPOINT_TYPE_BULK | usbEndpointOut:
nrf.USBD.INTENSET.Set(nrf.USBD_INTENSET_ENDEPOUT0 << ep)
nrf.USBD.SIZE.EPOUT[ep].Set(0)
enableEPOut(ep)
case usb_ENDPOINT_TYPE_INTERRUPT | usbEndpointOut:
nrf.USBD.INTENSET.Set(nrf.USBD_INTENSET_ENDEPOUT0 << ep)
nrf.USBD.SIZE.EPOUT[ep].Set(0)
enableEPOut(ep)
case usb_ENDPOINT_TYPE_BULK | usbEndpointIn:
enableEPIn(ep)
case usb_ENDPOINT_TYPE_CONTROL:
enableEPIn(0)
enableEPOut(0)
nrf.USBD.INTENSET.Set(nrf.USBD_INTENSET_ENDEPOUT0)
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
}
func handleStandardSetup(setup usbSetup) bool {
switch setup.bRequest {
case usb_GET_STATUS:
buf := []byte{0, 0}
if setup.bmRequestType != 0 { // endpoint
if isEndpointHalt {
buf[0] = 1
}
}
sendUSBPacket(0, buf)
return true
case usb_CLEAR_FEATURE:
if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
isRemoteWakeUpEnabled = false
} else if setup.wValueL == 0 { // ENDPOINTHALT
isEndpointHalt = false
}
nrf.USBD.TASKS_EP0STATUS.Set(1)
return true
case usb_SET_FEATURE:
if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
isRemoteWakeUpEnabled = true
} else if setup.wValueL == 0 { // ENDPOINTHALT
isEndpointHalt = true
}
nrf.USBD.TASKS_EP0STATUS.Set(1)
return true
case usb_SET_ADDRESS:
// nrf USBD handles this
return true
case usb_GET_DESCRIPTOR:
sendDescriptor(setup)
return true
case usb_SET_DESCRIPTOR:
return false
case usb_GET_CONFIGURATION:
buff := []byte{usbConfiguration}
sendUSBPacket(0, buff)
return true
case usb_SET_CONFIGURATION:
if setup.bmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
nrf.USBD.TASKS_EP0STATUS.Set(1)
for i := 1; i < len(endPoints); i++ {
initEndpoint(uint32(i), endPoints[i])
}
usbConfiguration = setup.wValueL
return true
} else {
return false
}
case usb_GET_INTERFACE:
buff := []byte{usbSetInterface}
sendUSBPacket(0, buff)
return true
case usb_SET_INTERFACE:
usbSetInterface = setup.wValueL
nrf.USBD.TASKS_EP0STATUS.Set(1)
return true
default:
return true
}
}
func cdcSetup(setup usbSetup) bool {
if setup.bmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
if setup.bRequest == usb_CDC_GET_LINE_CODING {
b := make([]byte, 7)
b[0] = byte(usbLineInfo.dwDTERate)
b[1] = byte(usbLineInfo.dwDTERate >> 8)
b[2] = byte(usbLineInfo.dwDTERate >> 16)
b[3] = byte(usbLineInfo.dwDTERate >> 24)
b[4] = byte(usbLineInfo.bCharFormat)
b[5] = byte(usbLineInfo.bParityType)
b[6] = byte(usbLineInfo.bDataBits)
sendUSBPacket(0, b)
return true
}
}
if setup.bmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
if setup.bRequest == usb_CDC_SET_LINE_CODING {
epout0data_setlinecoding = true
nrf.USBD.TASKS_EP0RCVOUT.Set(1)
return true
}
if setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
usbLineInfo.lineState = setup.wValueL
checkShouldReset()
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
if setup.bRequest == usb_CDC_SEND_BREAK {
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
return true
}
return false
}
//go:noinline
func sendUSBPacket(ep uint32, data []byte) {
count := len(data)
copy(udd_ep_in_cache_buffer[ep][:], data)
if ep == 0 && count > usbEndpointPacketSize {
sendOnEP0DATADONE.ptr = &udd_ep_in_cache_buffer[ep][usbEndpointPacketSize]
sendOnEP0DATADONE.count = count - usbEndpointPacketSize
count = usbEndpointPacketSize
}
sendViaEPIn(
ep,
&udd_ep_in_cache_buffer[ep][0],
count,
)
}
func (usbcdc USBCDC) handleEndpoint(ep uint32) {
// get data
count := int(nrf.USBD.EPOUT[ep].AMOUNT.Get())
// move to ring buffer
for i := 0; i < count; i++ {
usbcdc.Receive(byte(udd_ep_out_cache_buffer[ep][i]))
}
// set ready for next data
nrf.USBD.SIZE.EPOUT[ep].Set(0)
}
func sendZlp() {
nrf.USBD.TASKS_EP0STATUS.Set(1)
}
func sendViaEPIn(ep uint32, ptr *byte, count int) {
nrf.USBD.EPIN[ep].PTR.Set(
uint32(uintptr(unsafe.Pointer(ptr))),
)
nrf.USBD.EPIN[ep].MAXCNT.Set(uint32(count))
nrf.USBD.TASKS_STARTEPIN[ep].Set(1)
}
func enableEPOut(ep uint32) {
epouten = epouten | (nrf.USBD_EPOUTEN_OUT0 << ep)
nrf.USBD.EPOUTEN.Set(epouten)
}
func enableEPIn(ep uint32) {
epinen = epinen | (nrf.USBD_EPINEN_IN0 << ep)
nrf.USBD.EPINEN.Set(epinen)
}