From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH] OMAP3: PM: Force write last pad config register into save area Date: Tue, 17 Nov 2009 11:17:00 -0600 Message-ID: <4B02DA8C.3060801@ti.com> References: <> <1258475693-22068-1-git-send-email-tero.kristo@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from arroyo.ext.ti.com ([192.94.94.40]:53508 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752580AbZKQRQ7 (ORCPT ); Tue, 17 Nov 2009 12:16:59 -0500 In-Reply-To: <1258475693-22068-1-git-send-email-tero.kristo@nokia.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tero Kristo Cc: "linux-omap@vger.kernel.org" Tero Kristo had written, on 11/17/2009 10:34 AM, the following: > From: Tero Kristo > > Due to OMAP3 errata XYZ, the save of the last pad register (ETK_D14 and > ETK_D15) can fail sometimes when there is simultaneous OCP access to the > SCM register area. Fixed by writing the last register to the save area. > > Also, optimized the delay loop for the HW save to include an udelay(1), > which limits the number of unnecessary HW accesses to SCM register area > during the save. Nitpicky minor comment: Should we split this out? Also, this replaces the patch discussed under: http://marc.info/?t=125474192000004&r=1&w=2 > > Signed-off-by: Tero Kristo Acked-by: Nishanth Menon > --- > arch/arm/mach-omap2/pm34xx.c | 10 +++++++++- > 1 files changed, 9 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c > index 4b01303..4ead40e 100644 > --- a/arch/arm/mach-omap2/pm34xx.c > +++ b/arch/arm/mach-omap2/pm34xx.c > @@ -155,7 +155,15 @@ static void omap3_core_save_context(void) > /* wait for the save to complete */ > while (!(omap_ctrl_readl(OMAP343X_CONTROL_GENERAL_PURPOSE_STATUS) > & PADCONF_SAVE_DONE)) > - ; > + udelay(1); > + > + /* > + * Force write last pad into memory, as this can fail in some > + * cases according to errata XYZ > + */ > + omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14), > + OMAP343X_CONTROL_MEM_WKUP + 0x2a0); > + > /* Save the Interrupt controller context */ > omap_intc_save_context(); > /* Save the GPMC context */ -- Regards, Nishanth Menon