From patchwork Thu Mar 31 08:49:00 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kumar Gala X-Patchwork-Id: 89044 X-Patchwork-Delegate: galak@kernel.crashing.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from theia.denx.de (theia.denx.de [85.214.87.163]) by ozlabs.org (Postfix) with ESMTP id 66E25B6F85 for ; Thu, 31 Mar 2011 19:49:15 +1100 (EST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id A7910280ED; Thu, 31 Mar 2011 10:49:13 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id DrlJfe0oDzcR; Thu, 31 Mar 2011 10:49:13 +0200 (CEST) Received: from theia.denx.de (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 058C5280E6; Thu, 31 Mar 2011 10:49:11 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by theia.denx.de (Postfix) with ESMTP id 67A44280E8 for ; Thu, 31 Mar 2011 10:49:08 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at theia.denx.de Received: from theia.denx.de ([127.0.0.1]) by localhost (theia.denx.de [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ikYE+ETeiS3l for ; Thu, 31 Mar 2011 10:49:07 +0200 (CEST) X-policyd-weight: NOT_IN_SBL_XBL_SPAMHAUS=-1.5 NOT_IN_SPAMCOP=-1.5 NOT_IN_BL_NJABL=-1.5 (only DNSBL check requested) Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by theia.denx.de (Postfix) with ESMTPS id 08A2D280E6 for ; Thu, 31 Mar 2011 10:49:04 +0200 (CEST) Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id p2V8n1Wg027313; Thu, 31 Mar 2011 03:49:01 -0500 From: Kumar Gala To: u-boot@lists.denx.de Date: Thu, 31 Mar 2011 03:49:00 -0500 Message-Id: <1301561341-14495-1-git-send-email-galak@kernel.crashing.org> X-Mailer: git-send-email 1.5.6.5 Cc: Timur Tabi Subject: [U-Boot] [PATCH 1/2] p4080ds: add README.p4080ds which documents the "serdes" hwconfig option X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.9 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: u-boot-bounces@lists.denx.de Errors-To: u-boot-bounces@lists.denx.de From: Timur Tabi Add documentation for the "serdes" hwconfig option, which is used to specify the status of SerDes banks two and three for the SERDES8 erratum work-around. Signed-off-by: Timur Tabi Signed-off-by: Kumar Gala --- doc/README.p4080ds | 32 ++++++++++++++++++++++++++++++++ 1 files changed, 32 insertions(+), 0 deletions(-) create mode 100644 doc/README.p4080ds diff --git a/doc/README.p4080ds b/doc/README.p4080ds new file mode 100644 index 0000000..3ed59a8 --- /dev/null +++ b/doc/README.p4080ds @@ -0,0 +1,32 @@ +Overview +-------- +The P4080DS is a Freescale reference board that hosts the eight-core P4080 SOC. + +SerDes hwconfig configuration +----------------------------- +The P4080 RCW includes three sets of bits the specify which SerDes lanes +should be powered down: SRDS_LPD_B1 (for bank one), SRDS_LPD_B2 (for bank two), +and SRDS_LPD_B3 (for bank three). Each of these contains four bits, one for +each lane in the bank. SerDes Erratum SERDES8 requires that SRDS_LPD_B2 and +SRDS_LPD_B3 be set to 0b1111. This forces banks two and three to be powered +down at reset. + +To re-enable these banks in U-Boot, two hwconfig are available: +"fsl_srds_lpd_b2" and "fsl_srds_lpd_b3". The value passed via fsl_srds_lpd_b2 +is written into SRDS_LPD_B2, and the value passed via fsl_srds_lpd_b3 is into +SRDS_LPD_B3. Each bit represents one of each bank, and a value of '1' +indicates that the lane should be powered down. + +For example, to indicate that both SerDes banks 2 and 3 are powered down, add +the following to hwconfig: + + serdes:fsl_srds_lpd_b2=0xf,fsl_srds_lpd_b3=0xf + +The "0xf" is a mask that corresponds to the 4 lanes A-D. The most significant +bit corresponds to lane A. To indicate that just lane A of bank 3 is to be +powered down, use: + + serdes:fsl_srds_lpd_b3=8 + +These options should be specified only if U-Boot does not automatically power +on the correct lanes.