From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id F3B521007D3 for ; Sat, 21 Jan 2012 10:06:17 +1100 (EST) Message-ID: <1327100755.2923.6.camel@pasglop> Subject: Re: [PATCH] powerpc/booke64: Configurable lazy interrupt disabling From: Benjamin Herrenschmidt To: Stuart Yoder Date: Sat, 21 Jan 2012 10:05:55 +1100 In-Reply-To: References: <1326897306-3924-1-git-send-email-Laurentiu.Tudor@freescale.com> <1326921026.26116.34.camel@pasglop> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Laurentiu Tudor , linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, 2012-01-19 at 13:29 -0600, Stuart Yoder wrote: > Also, Scott had posted an approach to do option #2 a while back, > but as I recall there was some negative feedback about this. See: > I see... the problems with doorbells are workable tho. A reject hcall could also raise the CPU priority to avoid lower priority interrupts for example. The decrementer option works too. Another approach is to do an hcall into the interrupt re-enable path when an interrupt occurred while masked, which is what we do on i or ps3, which could then trigger a replay. Traditionally EE's have always been "level sensitive" on PowerPC, the way you changed that is arguably an utterly broken HW design and I am not too keen on changing our core interrupt handling to deal with it via ifdef's if we can find a less invasive solution. Cheers, Ben.