Re: [uCsimm] Interrupts & ColdFire

From: Greg Ungerer (gerg@moreton.com.au)
Date: Thu Jun 29 2000 - 20:02:58 EDT


Hi Olivier,

Olivier Bouyssou wrote:
> In my design I use a st16c2550 device from Exar (a 16550A like). One of
> his interrupt line is connected to IRQ7 of the 5206e.
> My problems occur when i use this device : the kernel freeze and
> enter in a infinit loop after a variable time of use.
>
> So my questions are :
>
> - Does the driver (serial.c) for the 16550 of the uClinux distribution
> for ColdFire work correctly ?

Yep, I use it with a Connectix modem chip (which has built in 16550
UART).

> - Is it possible to use the interruptions of level 7 without affected
> the operation of the kernel ?

Most definately. IRQ7 is special on the ColdFire's. It is, when enabled,
a Non-maskable interrupt. The usual cli/sti protections don't apply
to it. So the code for something like the serial.c driver is simply
not going to work as you expect.

I would strongly recommend using another IRQ line if you have one spare.

Seeya
Greg

------------------------------------------------------------------------
Greg Ungerer EMAIL: gerg@moreton.com.au
Moreton Bay (A Lineo Company) PHONE: +61 7 3279 1822
Unit 12, 97 Jijaws St, FAX: +61 7 3279 1820
Sumner Park, QLD, 4074, Australia WEB: www.moretonbay.com
This message resent by the ucsimm@uclinux.com list server http://www.uClinux.com/



This archive was generated by hypermail 2b30 : Sun Apr 07 2002 - 00:01:37 EST