From patchwork Tue May 26 22:12:35 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Walmsley X-Patchwork-Id: 26116 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n4QMN9mr000384 for ; Tue, 26 May 2009 22:23:10 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758200AbZEZWWh (ORCPT ); Tue, 26 May 2009 18:22:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758716AbZEZWWg (ORCPT ); Tue, 26 May 2009 18:22:36 -0400 Received: from utopia.booyaka.com ([72.9.107.138]:33592 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758200AbZEZWWd (ORCPT ); Tue, 26 May 2009 18:22:33 -0400 Received: (qmail 21955 invoked by uid 526); 26 May 2009 22:22:28 -0000 MBOX-Line: From nobody Tue May 26 16:12:35 2009 From: Paul Walmsley Subject: [PATCH 08/10] OMAP3 SDRC: set FIXEDDELAY when disabling SDRC DLL To: linux-arm-kernel@lists.arm.linux.org.uk Cc: linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Paul Walmsley Date: Tue, 26 May 2009 16:12:35 -0600 Message-ID: <20090526221234.25381.63193.stgit@localhost.localdomain> In-Reply-To: <20090526220517.25381.75976.stgit@localhost.localdomain> References: <20090526220517.25381.75976.stgit@localhost.localdomain> User-Agent: StGIT/0.14.3.222.gddca MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Correspondence with the TI OMAP hardware team indicates that SDRC_DLLA_CTRL.FIXEDDELAY should be initialized to 0x0f. This number was apparently derived from process validation. This is only used when the SDRC DLL is unlocked (e.g., SDRC clock frequency less than 83MHz). Signed-off-by: Paul Walmsley --- arch/arm/mach-omap2/sram34xx.S | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/arch/arm/mach-omap2/sram34xx.S b/arch/arm/mach-omap2/sram34xx.S index 487fa86..f41f8d9 100644 --- a/arch/arm/mach-omap2/sram34xx.S +++ b/arch/arm/mach-omap2/sram34xx.S @@ -41,8 +41,18 @@ #define SDRC_UNLOCK_DLL 0x1 /* SDRC_DLLA_CTRL bit settings */ +#define FIXEDDELAY_SHIFT 24 +#define FIXEDDELAY_MASK (0xff << FIXEDDELAY_SHIFT) #define DLLIDLE_MASK 0x4 +/* + * SDRC_DLLA_CTRL default values: TI hardware team indicates that + * FIXEDDELAY should be initialized to 0xf. This apparently was + * empirically determined during process testing, so no derivation + * was provided. + */ +#define FIXEDDELAY_DEFAULT (0x0f << FIXEDDELAY_SHIFT) + /* SDRC_DLLA_STATUS bit settings */ #define LOCKSTATUS_MASK 0x4 @@ -103,6 +113,8 @@ return_to_sdram: unlock_dll: ldr r11, omap3_sdrc_dlla_ctrl ldr r12, [r11] + and r12, r12, #FIXEDDELAY_MASK + orr r12, r12, #FIXEDDELAY_DEFAULT orr r12, r12, #DLLIDLE_MASK str r12, [r11] @ (no OCP barrier needed) bx lr