On Thu, Oct 25, 2007 at 03:58:54PM +0200, Jan Nikitenko wrote: > UART0 on Alchemy mips platforms (au1xxx) does not use real uart's hw > irq, causing 'ttyS0: 1 input overrun(s)' kernel message with data loss, > when more characters than uart's fifo size were to be received by the uart. > > This problem can be experienced for example when uart0 is used as a > serial console on au1550 and more than 16 characters are pasted from > clipboard to the console. > > The is_real_interrupt(irq) macro is defined in drivers/serial/8250.c as > a check, if the irq number is other than zero. > Because UART0 on au1xxx platforms uses irq number 0, the > is_real_interrupt() check fails and serial8250_backup_timeout() is used > instead of uart's hw irq. > > The patch redefines the is_real_interrupt(irq) macro, as suggested in > the comment above the macro definition in 8250.c, in the > asm-mips/serial.h to be always true for CONFIG_SERIAL_8250_AU1X00. > This allows the irq number 0 to be used as hw irq for the alchemy uart0 > and fixes the overrun problem. > > Signed-off-by: Jan Nikitenko <jan.nikitenko@xxxxxxxxx> So applied to all of lmo's -stable branches. Ralf
