It's not an UART problem but a system performance issue, which is caused by the fact that SD driver lacks of card detection support. The card present polling in SDHCI based driver is very expense, and impacts system performance a lot. Adding card detection support solves the problem. The patch set targeting mainline was submitted as below.
http://thread.gmane.org/gmane.linux.kernel.mmc/8495 But it does not apply against Linaro kernel tree, neither .38 nor .39. I will probably submit a quick fix against Nicolas' .39 tree. Let me know if anyone has different opinion. -- You received this bug notification because you are a member of Linaro Release Team, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/754254 Title: imx51 randomly truncates serial input at 31 characters Status in Linaro Linux: New Status in “linux-linaro-mx51” package in Ubuntu: Confirmed Bug description: In the process of trying to work on some test automation, I noticed some commands were failing when sent to the serial port on my imx51 board. Sometimes the whole command would go through, sometimes it would truncate at 31 characters. I was not able to reproduce this in uboot, or with other boards I've tried so far. An easy way to reproduce, is to create a long string and cut/paste it on the serial console. Here's an example of me trying this: 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890 root@master:/# 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890^C root@master:/# 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890^C root@master:/# 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890^C root@master:/# 1234567890123456789012345678901^C root@master:/# 1234567890123456789012345678901^C root@master:/# 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890^C root@master:/# ^C root@master:/# 1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890^C root@master:/# 1234567890123456789012345678901 To manage notifications about this bug go to: https://bugs.launchpad.net/linux-linaro/+bug/754254/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~linaro-release Post to : [email protected] Unsubscribe : https://launchpad.net/~linaro-release More help : https://help.launchpad.net/ListHelp

