coldfire uart question

Angelo Dureghello
2017-10-15T17:28:07Z

Hi all,

i was trying a file transfer with xmodem-1k
and uClinux "rx" on the mcf54415 stnmark2 board side.

This using a recent mainline kernel:
/ # cat /proc/version
uClinux version 4.14.0-rc4stmark2-001-00118-g811fdbb62a9d
/ #

So, as per xmodem-1k, i send 3 bytes header,
a 1024 bytes block, and 2 bytes crc16. But "rx" timeouts
waiting the block.

Adding some traces to "rx", it timeouts since some bytes
(5 to 10) randomly positioned in the block are not received.
Of course they have been sent (scope checked).

The same 1024 bytes transfer in u-boot (y-modem)
always succeed.

Since mcf54415 has a 4 slots RX fifo UART, i was wondering
if the mcf.c uart driver is not fast enough to read the data,
or, where the "linux" limitation could be.

Regards,
Angelo Dureghello