UART #1 access on Sequoia board

UART #1 access on Sequoia board

[Muhammad Waseem]

[-- Attachment #1: Type: text/plain, Size: 389 bytes --]

Hello,
   I am working on PPC440EPx (Sequoia) to access its UART # 1 port for data
transfer, while UART # 0 is connected to remote terminal access on host.
However there is no module/driver listed for UART # 1 using 'lsmod'. The
kernel version is 2.6.23. How can I access the UART # 1 in user space and/or
kernel space? Do I need to develop own BSP for this? please help.

regards,
Waseem

[-- Attachment #2: Type: text/html, Size: 458 bytes --]

Re: UART #1 access on Sequoia board

[Josh Boyer]

On Mon, May 23, 2011 at 11:34:26AM +0500, Muhammad Waseem wrote:
>Hello,
>   I am working on PPC440EPx (Sequoia) to access its UART # 1 port for data
>transfer, while UART # 0 is connected to remote terminal access on host.
>However there is no module/driver listed for UART # 1 using 'lsmod'. The
>kernel version is 2.6.23. How can I access the UART # 1 in user space and/or
>kernel space? Do I need to develop own BSP for this? please help.

The driver is normally built into the kernel.  If the board DTS file has
both UARTs listed, and you have /dev/ttyS1 on your rootfs you should be
able to use it.  However, Sequoia wasn't added until 2.6.24, so I'm not
really sure what kernel flavor you are using.

josh

Fwd: UART #1 access on Sequoia board

[Muhammad Waseem]

[-- Attachment #1: Type: text/plain, Size: 1140 bytes --]

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?

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

--
Waseem




On Mon, May 23, 2011 at 5:40 PM, Josh Boyer <jwboyer@linux.vnet.ibm.com>wrote:

> On Mon, May 23, 2011 at 11:34:26AM +0500, Muhammad Waseem wrote:
> >Hello,
> >   I am working on PPC440EPx (Sequoia) to access its UART # 1 port for
> data
> >transfer, while UART # 0 is connected to remote terminal access on host.
> >However there is no module/driver listed for UART # 1 using 'lsmod'. The
> >kernel version is 2.6.23. How can I access the UART # 1 in user space
> and/or
> >kernel space? Do I need to develop own BSP for this? please help.
>
> The driver is normally built into the kernel.  If the board DTS file has
> both UARTs listed, and you have /dev/ttyS1 on your rootfs you should be
> able to use it.  However, Sequoia wasn't added until 2.6.24, so I'm not
> really sure what kernel flavor you are using.
>
> josh
>

[-- Attachment #2: Type: text/html, Size: 1731 bytes --]

Re: Fwd: UART #1 access on Sequoia board

[Josh Boyer]

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