Re: 2.4.21: Sharing interrupts with serial console
From: linux-os (Dick Johnson) <hidden>
Date: 2005-08-04 11:17:04
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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 : **************************************************************** The information transmitted in this message is confidential and may be privileged. Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited. If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to DeliveryErrors@analogic.com - and destroy all copies of this information, including any attachments, without reading or disclosing them. Thank you.