Fwd: UART #1 access on Sequoia board

Josh Boyer jwboyer at linux.vnet.ibm.com
Tue May 24 06:42:08 EST 2011


On Tue, May 24, 2011 at 12:22:14AM +0500, Muhammad Waseem wrote:

Please don't top post.

>I am using kernel version 2.6.23 which came with the Sequoia support CD. So
>that means UART # 1 BSP would probably not there?  But device file
>/dev/ttyS1 is present in rootfs when listed using 'ls'. Do you think
>updating the kernel might solve the problem?

Not necessarily.  You can create device nodes on the rootfs without
anything being bound to them.  One of the easiest ways to see if
something discovered the serial port is to look in the boot output.  You
should see something like:

serial8250.0: ttyS0 at MMIO 0x1ef600300 (irq = 17) is a 16550A                  
console [ttyS0] enabled, bootconsole disabled                                   
console [ttyS0] enabled, bootconsole disabled                                   
serial8250.0: ttyS1 at MMIO 0x1ef600400 (irq = 18) is a 16550A                  
serial8250.0: ttyS2 at MMIO 0x1ef600500 (irq = 19) is a 16550A                  
serial8250.0: ttyS3 at MMIO 0x1ef600600 (irq = 20) is a 16550A   

or:

1ef600300.serial: ttyS0 at MMIO 0x1ef600300 (irq = 17) is a 16550               
1ef600400.serial: ttyS1 at MMIO 0x1ef600400 (irq = 18) is a 16550               
1ef600500.serial: ttyS2 at MMIO 0x1ef600500 (irq = 19) is a 16550               
1ef600600.serial: ttyS3 at MMIO 0x1ef600600 (irq = 20) is a 16550      

>BTW where can I see the board's DTS file?

arch/powerpc/boot/dts/sequoia.dts

josh


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