From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH v5 3/3] ARM: OMAP2+: onenand: prepare for gpmc driver migration Date: Mon, 2 Jul 2012 12:29:03 -0500 Message-ID: <4FF1DA5F.9000409@ti.com> References: <0a4c9edc1328f7789491e2acf5138364e08bf2cb.1340778003.git.afzal@ti.com> <20120627145844.GL3483@atomide.com> <20120628123207.GG19842@atomide.com> <4FEC89B9.3090404@ti.com> <20120702063651.GO4202@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from devils.ext.ti.com ([198.47.26.153]:46995 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751445Ab2GBR3J (ORCPT ); Mon, 2 Jul 2012 13:29:09 -0400 In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "Mohammed, Afzal" Cc: Tony Lindgren , "paul@pwsan.com" , "linux-omap@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" On 07/02/2012 04:43 AM, Mohammed, Afzal wrote: > Hi Tony, > > On Mon, Jul 02, 2012 at 12:06:51, Tony Lindgren wrote: >> * Jon Hunter [120628 09:48]: > >>> The above change seems to imply that Tony's n900 is dependent on the bootloader settings >>> and not those being set by the kernel. Ideally, we should not need to set the async mode >>> in the onenand before we set the onenand timings in the gpmc (per Afzal's changelog >>> comment). This appears backwards. >> >> That should not be the case, I'm more likely to believe in Afzal's explanation. > > Not sure whether you are fine with fixing up this patch with added diff > > Assuming inferences so far is not wrong, right now this patch with the added diff > would be perfectly fine. > > Problem would happen when we are at a stage to do gpmc reset using hwmod [seems > miles to go before I sleep {or read gpmc hwmod reset} ;)]. If bootloader left > onenand configured in sync mode, to switch onenand to async mode, first configuring > gpmc to sync mode would be required & for that we need frequency information > from onenand and to get that information from onenand, gpmc has to be configured > for sync mode and to configure gpmc to sync mode .... You are concerned about hwmod performing a reset of the gpmc during boot? We should be able to use the HWMOD_INIT_NO_RESET flag to prevent this. Would that work? Cheers Jon From mboxrd@z Thu Jan 1 00:00:00 1970 From: jon-hunter@ti.com (Jon Hunter) Date: Mon, 2 Jul 2012 12:29:03 -0500 Subject: [PATCH v5 3/3] ARM: OMAP2+: onenand: prepare for gpmc driver migration In-Reply-To: References: <0a4c9edc1328f7789491e2acf5138364e08bf2cb.1340778003.git.afzal@ti.com> <20120627145844.GL3483@atomide.com> <20120628123207.GG19842@atomide.com> <4FEC89B9.3090404@ti.com> <20120702063651.GO4202@atomide.com> Message-ID: <4FF1DA5F.9000409@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/02/2012 04:43 AM, Mohammed, Afzal wrote: > Hi Tony, > > On Mon, Jul 02, 2012 at 12:06:51, Tony Lindgren wrote: >> * Jon Hunter [120628 09:48]: > >>> The above change seems to imply that Tony's n900 is dependent on the bootloader settings >>> and not those being set by the kernel. Ideally, we should not need to set the async mode >>> in the onenand before we set the onenand timings in the gpmc (per Afzal's changelog >>> comment). This appears backwards. >> >> That should not be the case, I'm more likely to believe in Afzal's explanation. > > Not sure whether you are fine with fixing up this patch with added diff > > Assuming inferences so far is not wrong, right now this patch with the added diff > would be perfectly fine. > > Problem would happen when we are at a stage to do gpmc reset using hwmod [seems > miles to go before I sleep {or read gpmc hwmod reset} ;)]. If bootloader left > onenand configured in sync mode, to switch onenand to async mode, first configuring > gpmc to sync mode would be required & for that we need frequency information > from onenand and to get that information from onenand, gpmc has to be configured > for sync mode and to configure gpmc to sync mode .... You are concerned about hwmod performing a reset of the gpmc during boot? We should be able to use the HWMOD_INIT_NO_RESET flag to prevent this. Would that work? Cheers Jon