litex/misoclib/tools/litescope/host/driver/uart.py

import serial
from struct import *
from misoclib.tools.litescope.host.driver.reg import *


def write_b(uart, data):
    uart.write(pack('B', data))


class LiteScopeUARTDriver:
    cmds = {
        "write": 0x01,
        "read": 0x02
    }
    def __init__(self, port, baudrate=115200, addrmap=None, busword=8, debug=False):
        self.port = port
        self.baudrate = str(baudrate)
        self.debug = debug
        self.uart = serial.Serial(port, baudrate, timeout=0.25)
        if addrmap is not None:
            self.regs = build_map(addrmap, busword, self.read, self.write)

    def open(self):
        self.uart.flushOutput()
        self.uart.close()
        self.uart.open()
        self.uart.flushInput()
        try:
            self.regs.uart2wb_sel.write(1)
        except:
            pass

    def close(self):
        try:
            self.regs.uart2wb_sel.write(0)
        except:
            pass
        self.uart.flushOutput()
        self.uart.close()

    def read(self, addr, burst_length=None, repeats=None):
        datas = []
        def to_int(v):
            return 1 if v is None else v
        for i in range(to_int(repeats)):
            self.uart.flushInput()
            write_b(self.uart, self.cmds["read"])
            write_b(self.uart, burst_length)
            write_b(self.uart, (addr//4 & 0xff000000) >> 24)
            write_b(self.uart, (addr//4 & 0x00ff0000) >> 16)
            write_b(self.uart, (addr//4 & 0x0000ff00) >> 8)
            write_b(self.uart, (addr//4 & 0x000000ff))
            for j in range(to_int(burst_length)):
                data = 0
                for k in range(4):
                    data = data << 8
                    data |= ord(self.uart.read())
                if self.debug:
                    print("RD {:08X} @ {:08X}".format(data, (addr+j)*4))
                datas.append(data)
        return datas

    def write(self, addr, data):
        if isinstance(data, list):
            burst_length = len(data)
        else:
            burst_length = 1
        write_b(self.uart, self.cmds["write"])
        write_b(self.uart, burst_length)
        write_b(self.uart, (addr//4 & 0xff000000) >> 24)
        write_b(self.uart, (addr//4 & 0x00ff0000) >> 16)
        write_b(self.uart, (addr//4 & 0x0000ff00) >> 8)
        write_b(self.uart, (addr//4 & 0x000000ff))
        if isinstance(data, list):
            for i in range(len(data)):
                dat = data[i]
                for j in range(4):
                    write_b(self.uart, (dat & 0xff000000) >> 24)
                    dat = dat << 8
                if self.debug:
                    print("WR {:08X} @ {:08X}".format(data[i], (addr + i)*4))
        else:
            dat = data
            for j in range(4):
                write_b(self.uart, (dat & 0xff000000) >> 24)
                dat = dat << 8
            if self.debug:
                print("WR {:08X} @ {:08X}".format(data, (addr * 4)))