From mboxrd@z Thu Jan 1 00:00:00 1970 From: "G, Manjunath Kondaiah" Subject: Re: [PATCH v7] OMAP2+: PM: omap device: API's for handling mstandby mode Date: Thu, 2 Dec 2010 19:53:30 +0530 Message-ID: <20101202142329.GA21529@GLPP-machine> References: <1291298392-28729-1-git-send-email-manjugk@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from na3sys009aog111.obsmtp.com ([74.125.149.205]:59477 "EHLO na3sys009aog111.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757715Ab0LBOXE (ORCPT ); Thu, 2 Dec 2010 09:23:04 -0500 Received: by mail-yw0-f52.google.com with SMTP id 9so5650321ywf.25 for ; Thu, 02 Dec 2010 06:23:03 -0800 (PST) Content-Disposition: inline In-Reply-To: <1291298392-28729-1-git-send-email-manjugk@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: linux-omap@vger.kernel.org Cc: Kevin Hilman , Paul Walmsley , linux-arm-kernel@lists.infradead.org * G, Manjunath Kondaiah [2010-12-02 19:29:52 +0530]: > Certain errata in OMAP2+ processors will require forcing > master standby to "no standby" mode before completing on going > operation. Without this, the results will be unpredictable. > > Since current implementation of PM run time framework does not support > changing sysconfig settings during middle of the on going operation, > these API's will support the same. One API will force the device's > sysconfig mstandby mode settings to "no standby" and other API will > release "no standby" mode and sets it to "smart standby" or "no > standby? depending on HWMOD_SWSUP_MSTANDBY value. > > The hwmod API "omap_hwmod_set_master_standbymode" will use > no_stdby_cnt(introduced in omap_hwmod structure) for controlling > access to sysconfig register settings in case of overlapping > request/release API's are called. It also disables interrupts during > syconfig register access. > > These API's should be used by device drivers only incase of > erratum applicable to their modules if there is no other methods > to resolve. > > These API's are required for multiple DMA errata which require > putting DMA controller in no mstandby mode before stopping dma. > > The applicable errata: > 1. Erratum ID: i557(Applicable for omap36xx all ES versions) > The channel hangs when the Pause bit (DMA4_CDPi [7] ) is cleared > through config port while in Standby. > > 2. Erratum ID: i541 > sDMA FIFO draining does not finish. Applicable to all omap2+ except > omap4. > > 3. Erratum ID:i88 > The sDMA to be put in no mstandby mode before disabling the channel > after completing the data transfer operation. > Applicable only for OMAP3430 ES1.0 > > Also fixes typo HWMOD_SWSUP_MSTDBY to HWMOD_SWSUP_MSTANDBY in > omap_hwmod.h > > Signed-off-by: G, Manjunath Kondaiah > Cc: Kevin Hilman > Cc: Paul Walmsley > Cc: linux-arm-kernel@lists.infradead.org Pls ignore this patch. I have resent this patch as: [PATCH v7 RESEND] OMAP2+: PM: omap device: API's for handling mstandby mode Sorry for noise. -Manjunath [...] From mboxrd@z Thu Jan 1 00:00:00 1970 From: manjugk@ti.com (G, Manjunath Kondaiah) Date: Thu, 2 Dec 2010 19:53:30 +0530 Subject: [PATCH v7] OMAP2+: PM: omap device: API's for handling mstandby mode In-Reply-To: <1291298392-28729-1-git-send-email-manjugk@ti.com> References: <1291298392-28729-1-git-send-email-manjugk@ti.com> Message-ID: <20101202142329.GA21529@GLPP-machine> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org * G, Manjunath Kondaiah [2010-12-02 19:29:52 +0530]: > Certain errata in OMAP2+ processors will require forcing > master standby to "no standby" mode before completing on going > operation. Without this, the results will be unpredictable. > > Since current implementation of PM run time framework does not support > changing sysconfig settings during middle of the on going operation, > these API's will support the same. One API will force the device's > sysconfig mstandby mode settings to "no standby" and other API will > release "no standby" mode and sets it to "smart standby" or "no > standby? depending on HWMOD_SWSUP_MSTANDBY value. > > The hwmod API "omap_hwmod_set_master_standbymode" will use > no_stdby_cnt(introduced in omap_hwmod structure) for controlling > access to sysconfig register settings in case of overlapping > request/release API's are called. It also disables interrupts during > syconfig register access. > > These API's should be used by device drivers only incase of > erratum applicable to their modules if there is no other methods > to resolve. > > These API's are required for multiple DMA errata which require > putting DMA controller in no mstandby mode before stopping dma. > > The applicable errata: > 1. Erratum ID: i557(Applicable for omap36xx all ES versions) > The channel hangs when the Pause bit (DMA4_CDPi [7] ) is cleared > through config port while in Standby. > > 2. Erratum ID: i541 > sDMA FIFO draining does not finish. Applicable to all omap2+ except > omap4. > > 3. Erratum ID:i88 > The sDMA to be put in no mstandby mode before disabling the channel > after completing the data transfer operation. > Applicable only for OMAP3430 ES1.0 > > Also fixes typo HWMOD_SWSUP_MSTDBY to HWMOD_SWSUP_MSTANDBY in > omap_hwmod.h > > Signed-off-by: G, Manjunath Kondaiah > Cc: Kevin Hilman > Cc: Paul Walmsley > Cc: linux-arm-kernel at lists.infradead.org Pls ignore this patch. I have resent this patch as: [PATCH v7 RESEND] OMAP2+: PM: omap device: API's for handling mstandby mode Sorry for noise. -Manjunath [...]