Re: 2.4.21: Sharing interrupts with serial console

["linux-os \(Dick Johnson\)" <linux-os@analogic.com>]

On Wed, 3 Aug 2005, Chris Budd wrote:

> I have read http://www.tldp.org/HOWTO/Remote-Serial-Console-HOWTO/preparation-setport.html
> and http://www.linux-mips.org/archives/linux-mips/2004-04/msg00134.html
> and other items, but I still have not found the answers to the
> following questions:
>
> 1.  The rs_init function in ./linux-2.4.21/drivers/char/serial.c
> explicitly states "The interrupt of the serial console port can't be
> shared."  Does this include *ALL* interrupts?  The code checks for
> sharing only with other serial devices, not *ALL* types of devices
> like I2C, RTC, etc.
>
> 2.  While the presence of the comment about not sharing was nice, it
> does not explain "why?"  Why can't we share the serial console
> interrupt?  The serial console seems to work when I alter serial.c to
> skip this check for the sharing of interrupts with the serial console.
>
> 3.  Does the hardware platform matter?  We are running Linux 2.4.21 on
> an embedded XScale(ARM)-based board.
>
> Thanks,
> Chris.
> -

Only LEVEL interrupts can be shared, and all the drivers that
share that one interrupt need to be designed for sharing.


Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
Warning : 98.36% of all statistics are fiction.
.
I apologize for the following. I tried to kill it with the above dot :

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