On Friday, 13 July 2018 14:32:42 MSK David R. Piegdon wrote: > Hi, > a while back I sent a few mails regarding spurious interrupts in the > UARTA (hsuart) block of the Tegra2 SoC, when using the 8250 driver for > it instead of the hsuart driver. After going down a pretty deep > debugging/testing hole, I think I found a patch that fixes the issue. So > far testing in a reboot-cycle suggests that the error frequency dropped > from >3% of all reboots to at least <0.05% of all reboots. Tests > continue to run over the weekend. > > The patch below already is a second iteration; the first did not reset > the MCR or contain the lines below '// clear interrupts'. This resulted > in no more spurious interrupts, but in a few % of spurious interrupts > that were recovered the UART block did not receive any characters any > more. So further resetting was required to fully reacquire operational > state of the UART block. > > I'd love any comments/suggestions on this! > I'm wondering whether later Tegra's have that issue as well, maybe Mikko knows? Instead of #ifdef-ing T20 in the code, there probably should be some kind of a port flag. Please send a proper patch and follow suggestions from tty/ maintainers. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
