Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753665Ab3GXSwh (ORCPT ); Wed, 24 Jul 2013 14:52:37 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:36494 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753094Ab3GXSwe (ORCPT ); Wed, 24 Jul 2013 14:52:34 -0400 Message-ID: <51F0223E.4050008@ti.com> Date: Wed, 24 Jul 2013 13:51:42 -0500 From: Nishanth Menon User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: Sricharan R CC: Santosh Shilimkar , Linus Walleij , "linux-kernel@vger.kernel.org" , "devicetree-discuss@lists.ozlabs.org" , "linux-doc@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Linux-OMAP , ext Tony Lindgren , Russell King - ARM Linux , Rajendra Nayak , Felipe Balbi , Thomas Gleixner , Grant Likely Subject: Re: [PATCH 1/3] misc: Add crossbar driver References: <1374165830-6367-1-git-send-email-r.sricharan@ti.com> <1374165830-6367-2-git-send-email-r.sricharan@ti.com> <51E83A4F.5080904@ti.com> <51ED2385.60108@ti.com> <51ED5C66.1010407@ti.com> <51EFFBE1.4090505@ti.com> <51F0031B.1050307@ti.com> <51F00530.9090703@ti.com> <51F02069.3050207@ti.com> In-Reply-To: <51F02069.3050207@ti.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1721 Lines: 31 On 07/24/2013 01:43 PM, Sricharan R wrote: > On Wednesday 24 July 2013 10:17 PM, Nishanth Menon wrote: >> On 07/24/2013 11:38 AM, Santosh Shilimkar wrote: >>> On Wednesday 24 July 2013 12:08 PM, Nishanth Menon wrote: >>>> That said, maybe a intermediate pinctrl approach might be more pragmatic and less theoretically flexible. >>>> an option might be to "statically allocate" default number of interrupts to a domain - example: >>>> * GIC IRQ 72->78 allotted to UARTs >>>> * pinctrl mapping provided for those but only 6 can be used (rest are marked status="disabled" as default) at any given time (choice of pinctrl option determines GIC interrupt line to use) >>>> * All modules will have a pinctrl definition to have a mapping - to avoid bootloader overriding default cross bar setting in ways un-expected by kernel. >>>> >>>> Does that sound fair trade off? >>> This sounds better. That way we can get all the devices in the DT at least. >> >> Fair enough - if Linus and Tony are still ok with this approach to the problem, seeing a patch series with the effect would be beneficial. >> > Ok, i will use this idea of certain number interrupts to groups. > Yes on DRA7XX, we have about 160 gic lines and 320 irq crossbar device inputs contending for it. > 1:2 and fully arbitrary. But will we be really exhausting them ? > Depends on how we allocate :). The default arbitary allocation can be made more logical in your series ofcourse :). -- Regards, Nishanth Menon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/