litex/misoclib/com/liteusb/software/wishbone.py

79 lines
2.6 KiB
Python

from misoclib.com.liteusb.software.ftdi import FTDIComDevice
class LiteUSBWishboneDriverFTDI:
cmds = {
"write": 0x01,
"read": 0x02
}
def __init__(self, interface, mode, tag, addrmap=None, busword=8, debug=False):
self.interface = interface
self.mode = mode
self.tag = tag
self.debug = debug
self.com = FTDIComDevice(self.interface,
mode=mode,
uart_tag=tag,
dma_tag=16, # XXX FIXME
verbose=debug)
if addrmap is not None:
self.regs = build_map(addrmap, busword, self.read, self.write)
def open(self):
self.com.open()
def close(self):
self.com.close()
# XXX regroup cmds in a single packet
def read(self, addr, burst_length=1):
datas = []
self.com.uartflush()
self.com.uartwrite(self.cmds["read"])
self.com.uartwrite(burst_length)
word_addr = addr//4
self.com.uartwrite((word_addr >> 24) & 0xff)
self.com.uartwrite((word_addr >> 16) & 0xff)
self.com.uartwrite((word_addr >> 8) & 0xff)
self.com.uartwrite((word_addr >> 0) & 0xff)
for i in range(burst_length):
data = 0
for k in range(4):
data = data << 8
data |= self.com.uartread()
if self.debug:
print("RD {:08X} @ {:08X}".format(data, addr + 4*i))
datas.append(data)
if burst_length == 1:
return datas[0]
else:
return datas
# XXX regroup cmds in a single packet
def write(self, addr, data):
if isinstance(data, list):
burst_length = len(data)
else:
burst_length = 1
data = [data]
self.com.uartwrite(self.cmds["write"])
self.com.uartwrite(burst_length)
word_addr = addr//4
self.com.uartwrite((word_addr >> 24) & 0xff)
self.com.uartwrite((word_addr >> 16) & 0xff)
self.com.uartwrite((word_addr >> 8) & 0xff)
self.com.uartwrite((word_addr >> 0) & 0xff)
for i in range(len(data)):
dat = data[i]
for j in range(4):
self.com.uartwrite((dat >> 24) & 0xff)
dat = dat << 8
if self.debug:
print("WR {:08X} @ {:08X}".format(data[i], addr + 4*i))
def LiteUSBWishboneDriver(chip="ft2232h", *args, **kwargs):
drivers = {
"ft2232h": LiteUSBWishboneDriverFTDI
}
return drivers[chip](*args, **kwargs)