On Wed, 2017-03-01 at 18:02 +0000, James Hogan wrote: > On 11 January 2017 at 19:48, Jason Uy <jason.uy@xxxxxxxxxxxx> wrote: > > In the most common use case, the Synopsys DW UART driver does not > > set the set_termios callback function. This prevents UPSTAT_AUTOCTS > > from being set when the UART flag CRTSCTS is set. As a result, the > > driver will use software flow control as opposed to hardware flow > > control. > > > > To fix the problem, the set_termios callback function is set to the > > DW specific function. The logic to set UPSTAT_AUTOCTS is moved so > > that any clock error will not affect setting the hardware flow > > control. > Bisection shows that this patch, commit > 6a171b29937984a5e0bf29d6577b055998f03edb, has broken boot of the > Cavium Octeon III based UTM-8 board (MIPS architecture). > > I now get the following warning: > [<ffffffff8149c2e4>] uart_get_baud_rate+0xfc/0x1f0 > [<ffffffff814a5098>] serial8250_do_set_termios+0xb0/0x440 > [<ffffffff8149c710>] uart_set_options+0xe8/0x190 > [<ffffffff814a6cdc>] serial8250_console_setup+0x84/0x158 > [<ffffffff814a11ec>] univ8250_console_setup+0x54/0x70 > [<ffffffff811901a0>] register_console+0x1c8/0x418 > [<ffffffff8149f004>] uart_add_one_port+0x434/0x4b0 > [<ffffffff814a1af8>] serial8250_register_8250_port+0x2d8/0x440 > [<ffffffff814aa620>] dw8250_probe+0x388/0x5e8 > Then it hangs and the watchdog restarts the machine. > > Any ideas? 1. Does it use clock on that platform? 2. Check if termios is not NULL there. -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
