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Does anybody use DUART2 of P1010? I found it doesn't work.

Question asked by YanjunLuo1z on Sep 14, 2013

Hi all,

I have a new board of P1010 and we want to use the four uarts. I set the pin mux at u-boot, add the two serial ports in dts file, then I can see the /dev/ttyS2 and /dev/ttyS3 devices. But when I try to send out something, the kernel will crash, I found it can't exit the interrupt routine, and I can't see any thing out from the pin with scope. It looks like the DUART2 has something wrong, I don't know how can I enable it. Does anybody use it before?


Here is the serial port message at boot up. We can see the 4 serial ports is there.


"Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled

ttyS0: autoconf (0x0000, 0xd1010500):���3֢����16550A

serial8250.0: ttyS0 at MMIO 0xffe04500 (irq = 42) is a 16550A

console [ttyS0] enabled, bootconsole disabled

console [ttyS0] enabled, bootconsole disabled

ttyS1: autoconf (0x0000, 0xd1012600): iir=3 Motorola 8xxx DUART type=16550A

serial8250.0: ttyS1 at MMIO 0xffe04600 (irq = 42) is a 16550A

ttyS2: autoconf (0x0000, 0xd1014700): iir=3 Motorola 8xxx DUART type=16550A

serial8250.0: ttyS2 at MMIO 0xffe04700 (irq = 42) is a 16550A

ttyS3: autoconf (0x0000, 0xd1016800): iir=3 Motorola 8xxx DUART type=16550A

serial8250.0: ttyS3 at MMIO 0xffe04800 (irq = 42) is a 16550A



Here is the message when I write anything to /det/ttyS2.


serial8250: too much work for irq42



BTW, the /dev/ttyS0 and /dev/ttyS1 works fine, that means DUART1 is ok, but how can I use the DUART2?



Yanjun Luo.