"""
:attention: on USB the LSB bits are sent first
"""
from typing import Union
from hwt.code import In
from hwt.hdl.types.bits import Bits
from hwt.hdl.types.stream import HStream
from hwt.hdl.types.struct import HStruct
from hwt.synthesizer.rtlLevel.mainBases import RtlSignalBase
[docs]class USB_LINE_STATE():
SE0 = 0b00 # (D+, D-)= (0, 0)
J = 0b01 # (D+, D-)= (0, 1)
K = 0b10 # (D+, D-)= (1, 0)
SE1 = 0b11 # (D+, D-)= (1, 1)
[docs]class USB_VER:
"""
+-----------+-----------------------+
| USB_VER | Speed |
+-----------+-----------------------+
| 1.0 - 2.0 | Low Speed 1.5 Mbit/s |
+-----------+-----------------------+
| 1.0 - 2.0 | Full Speed 12 Mbit/s |
+-----------+-----------------------+
| 2.0 | High Speed 480 Mbit/s |
+-----------+-----------------------+
| 3.0 | SuperSpeed 5Gbit/s |
+-----------+-----------------------+
| 3.1 | SuperSpeed+ 10Gbit/s |
+-----------+-----------------------+
| 3.2 | SuperSpeed+ 20Gbit/s |
+-----------+-----------------------+
| 4.0 | SuperSpeed+ 40Gbit/s |
+-----------+-----------------------+
"""
USB1_0 = "1.0"
USB1_1 = "1.1"
USB2_0 = "2.0"
USB3_0 = "3.0"
USB3_1 = "3.1"
USB3_2 = "3.2"
USB4_0 = "4.0"
values = [USB1_0, USB1_1, USB2_0, USB3_0, USB3_1, USB3_2, USB4_0]
[docs] @staticmethod
def to_uint16_t(usbVer: str):
assert len(usbVer) == 3, usbVer
usb_ver_mayor, usb_ver_minor = usbVer.split(".")
usb_ver_mayor = ord(usb_ver_mayor) - ord('0')
usb_ver_minor = ord(usb_ver_minor) - ord('0')
usb_ver_minor <<= 4
return (usb_ver_minor | (usb_ver_mayor << 8))
[docs] @staticmethod
def from_uint16_t(usbVer: int):
buff = []
for _ in range(4):
d = usbVer & 0xF
buff.append(d)
usbVer >>= 4
if buff[3] == 0 and buff[0] == 0:
return f"{buff[2]:d}.{buff[1]:d}"
else:
return f"{buff[3]:d}{buff[2]:d}.{buff[1]:d}{buff[0]:d}"
[docs]class USB_PID:
"""
USB Protocol layer packet identifier values
(Specifies the type of transaction)
:attention: visualy written in msb-first, transmited in lsb first
:note: packet formats are described in structs in this file
:note: if the PID is in 8b format the other 4 bits (check field) are a bitwise inversion of original 4b PID field
"""
[docs] @classmethod
def is_token(cls, v: Union[int, RtlSignalBase]):
token_pids = (cls.TOKEN_OUT, cls.TOKEN_IN, cls.TOKEN_SOF, cls.TOKEN_SETUP)
if isinstance(v, int):
return v in token_pids
else:
return In(v, token_pids)
# Marks for host-to-device transfer
TOKEN_OUT = 0b0001 # 0x1
# Marks for device-to-host transfer
TOKEN_IN = 0b1001 # 0x9
# Marks start of frame marker (sent each ms)
TOKEN_SOF = 0b0101 # 0x5
# Marks for host-to-device control transfer
TOKEN_SETUP = 0b1101 # 0xD
# :note: setup transactions always uses DATA_0, but it may be fallowed by IN which starts with 0 and alternates between 0/1
[docs] @classmethod
def is_data(cls, v: Union[int, RtlSignalBase]):
data_pids = (cls.DATA_0, cls.DATA_1, cls.DATA_2, cls.DATA_M)
if isinstance(v, int):
return v in data_pids
else:
return In(v, data_pids)
# DATA_X is always relatd to a specific endpoint
# Even-numbered data packet
DATA_0 = 0b0011 # 0x3
# Odd-numbered data packet
DATA_1 = 0b1011 # 0xB
# Data packet for high-bandwidth isochronous transfer (USB 2.0)
DATA_2 = 0b0111 # 0x7
# Data packet for high-bandwidth isochronous transfer (USB 2.0)
DATA_M = 0b1111 # 0xF
[docs] @classmethod
def is_hs(cls, v: Union[int, RtlSignalBase]):
hs_pids = (cls.HS_ACK, cls.HS_NACK, cls.HS_STALL, cls.HS_NYET)
if isinstance(v, int):
return v in hs_pids
else:
return In(v, hs_pids)
# Data packet accepted
HS_ACK = 0b0010 # 0x2
# Data packet not accepted; please retransmit
HS_NACK = 0b1010 # 0XA
# Transfer impossible; do error recovery
HS_STALL = 0b1110 # 0xE
# Data not ready yet (USB 2.0)
HS_NYET = 0b0110 # 0x6
# Low-bandwidth USB preamble (tells hubs to temporarily switch to low speed mode)
PREAMBLE = 0b1100 # 0xC
# Split transaction error (USB 2.0)
ERR = 0b1100 # 0xC
# High-bandwidth (USB 2.0) split transaction
SPLIT = 0b1000 # 0x8
# Check if endpoint can accept data (USB 2.0)
PING = 0b0100 # 0x4
usb_addr_t = Bits(7)
usb_endp_t = Bits(4)
usb_crc5_t = Bits(5)
usb_crc16_t = Bits(16)
usb_pid_t = Bits(4)
"""
:attention: every packet starts with sync and ends in EOP,
which is not in data structures below
"""
"""
There are three types of token packets,
* In - Informs the USB device that the host wishes to read information.
* Out - Informs the USB device that the host wishes to send information.
* Setup - Used to begin control transfers.
"""
usb_packet_token_t = HStruct(
(usb_pid_t, "pid"),
(usb_addr_t, "addr"),
(usb_endp_t, "endp"),
(usb_crc5_t, "crc5"), # :note: does not involve USB_PID, only addr, endp
)
usb1_0_packet_data_t = HStruct(
(usb_pid_t, "pid"),
(HStream(Bits(8), frame_len=(1, 8)), "data"),
(usb_crc16_t, "crc"), # :note: not involves USB_PID, only data
)
usb1_1_packet_data_t = HStruct(
(usb_pid_t, "pid"),
(HStream(Bits(8), frame_len=(1, 1023)), "data"),
(usb_crc16_t, "crc"), # :note: not involves USB_PID, only data
)
usb2_0_packet_data_t = HStruct(
(usb_pid_t, "pid"),
(HStream(Bits(8), frame_len=(1, 1024)), "data"),
(usb_crc16_t, "crc"), # :note: not involves USB_PID, only data
)
"""
There are three type of handshake packets which consist simply of the USB_PID
* ACK - Acknowledgment that the packet has been successfully received.
* NAK - Reports that the device temporary cannot send or received data.
Also used during interrupt transactions to inform the host there is no data to send.
* STALL - The device finds its in a state that it requires intervention from the host.
"""
usb_packet_hs_t = HStruct(
(usb_pid_t, "pid"),
)
"""
The SOF (Start of Frame) packet consisting of an 11-bit frame number is sent by the host
every 1ms ± 500ns on a full speed bus or every 125 µs ± 0.0625 µs on a high speed bus.
"""
usb_frame_number_t = Bits(11)
usb_packet_sof_t = HStruct(
(usb_pid_t, "pid"),
(usb_frame_number_t, "frame_number"),
(usb_crc5_t, "crc5"), # :note: not involves USB_PID, only frame_number
)