comm_serial: allow to use dynamic baudrate

This commit is contained in:
Yann Sionneau 2014-12-01 18:03:01 +01:00 committed by Sebastien Bourdeauducq
parent 3ff3afe696
commit 20adb57140
2 changed files with 40 additions and 2 deletions

View File

@ -22,6 +22,7 @@ class _H2DMsgType(Enum):
REQUEST_IDENT = 1 REQUEST_IDENT = 1
LOAD_OBJECT = 2 LOAD_OBJECT = 2
RUN_KERNEL = 3 RUN_KERNEL = 3
UART_SET_BDRATE = 4
class _D2HMsgType(Enum): class _D2HMsgType(Enum):
@ -58,6 +59,34 @@ class Comm:
def __init__(self, dev="/dev/ttyUSB1", baud=115200): def __init__(self, dev="/dev/ttyUSB1", baud=115200):
self._fd = os.open(dev, os.O_RDWR | os.O_NOCTTY) self._fd = os.open(dev, os.O_RDWR | os.O_NOCTTY)
self.port = os.fdopen(self._fd, "r+b", buffering=0) self.port = os.fdopen(self._fd, "r+b", buffering=0)
self.dev = dev
real_baud = baud
baud = 115200
self.set_baud(baud)
if real_baud != baud:
baud = real_baud
self.set_remote_baud(baud)
self.set_baud(baud)
self.current_baud = baud
def set_remote_baud(self, baud):
clk_freq = 80000000
_write_exactly(self.port, struct.pack(
">lbl", 0x5a5a5a5a, _H2DMsgType.UART_SET_BDRATE.value,
int((baud/clk_freq)*2**32)))
handshake = 0
while handshake < 4:
recv = struct.unpack(
"B", _read_exactly(self.port, 1))
if recv[0] == 0x5a:
handshake += 1
else:
logger.debug("SYNC ERR {:02x}\n".format(int(recv[0])))
handshake = 0
self.set_baud(baud)
logger.debug("Synchronized")
def set_baud(self, baud):
iflag, oflag, cflag, lflag, ispeed, ospeed, cc = \ iflag, oflag, cflag, lflag, ispeed, ospeed, cc = \
termios.tcgetattr(self._fd) termios.tcgetattr(self._fd)
iflag = termios.IGNBRK | termios.IGNPAR iflag = termios.IGNBRK | termios.IGNPAR
@ -72,9 +101,12 @@ class Comm:
termios.tcdrain(self._fd) termios.tcdrain(self._fd)
termios.tcflush(self._fd, termios.TCOFLUSH) termios.tcflush(self._fd, termios.TCOFLUSH)
termios.tcflush(self._fd, termios.TCIFLUSH) termios.tcflush(self._fd, termios.TCIFLUSH)
logger.debug("connected to {} at {} baud".format(dev, baud)) logger.debug("connected to {} at {} baud".format(self.dev, baud))
def close(self): def close(self):
if self.current_baud != 115200:
self.set_remote_baud(115200)
self.set_baud(115200)
self.port.close() self.port.close()
def __enter__(self): def __enter__(self):

View File

@ -10,6 +10,7 @@ enum {
MSGTYPE_REQUEST_IDENT = 1, MSGTYPE_REQUEST_IDENT = 1,
MSGTYPE_LOAD_OBJECT, MSGTYPE_LOAD_OBJECT,
MSGTYPE_RUN_KERNEL, MSGTYPE_RUN_KERNEL,
MSGTYPE_UART_SETBDRATE,
}; };
/* device to host */ /* device to host */
@ -161,7 +162,12 @@ void comm_serve(object_loader load_object, kernel_runner run_kernel)
receive_and_load_object(load_object); receive_and_load_object(load_object);
else if(msgtype == MSGTYPE_RUN_KERNEL) else if(msgtype == MSGTYPE_RUN_KERNEL)
receive_and_run_kernel(run_kernel); receive_and_run_kernel(run_kernel);
else else if(msgtype == MSGTYPE_UART_SETBDRATE) {
unsigned int ftw = receive_int();
send_int(0x5a5a5a5a);
uart_sync();
uart_tuning_word_write(ftw);
} else
send_char(MSGTYPE_MESSAGE_UNRECOGNIZED); send_char(MSGTYPE_MESSAGE_UNRECOGNIZED);
} }
} }