From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e34.co.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 69EDF67C3D for ; Thu, 23 Nov 2006 05:36:15 +1100 (EST) Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e34.co.us.ibm.com (8.13.8/8.12.11) with ESMTP id kAMIaCNn013583 for ; Wed, 22 Nov 2006 13:36:12 -0500 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay04.boulder.ibm.com (8.13.6/8.13.6/NCO v8.1.1) with ESMTP id kAMIaCkZ532044 for ; Wed, 22 Nov 2006 11:36:12 -0700 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id kAMIaBIS024136 for ; Wed, 22 Nov 2006 11:36:12 -0700 Subject: Re: [PATCH] CAS DFP support From: Will Schmidt To: Kumar Gala In-Reply-To: References: <1164208814.1954.372.camel@goblue> <1164211565.4932.7.camel@otta> Content-Type: text/plain Date: Wed, 22 Nov 2006 12:36:09 -0600 Message-Id: <1164220570.8536.8.camel@localhost> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Peter Bergner , Paul Mackerras Reply-To: will_schmidt@vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2006-22-11 at 10:41 -0600, Kumar Gala wrote: > On Nov 22, 2006, at 10:06 AM, Peter Bergner wrote: > > > On Wed, 2006-11-22 at 09:46 -0600, Kumar Gala wrote: > >> On Nov 22, 2006, at 9:20 AM, Jake Moilanen wrote: > >> > >>> When booting a Power6 in compat mode, the DFP bit must be set in the > >>> client architecture call, or else firmware will downgrade the > >>> compliance > >>> to P5 compat mode, thus removing VMX and DFP instructions. > >>> > >>> Signed-off-by: Jake Moilanen > >>> > >>> --- 2.6/arch/powerpc/kernel/prom_init.c~ 2006-11-13 > >>> 15:01:13.000000000 > >>> -0600 > >>> +++ 2.6/arch/powerpc/kernel/prom_init.c 2006-11-21 > >>> 18:38:27.000000000 > >>> -0600 > >>> @@ -627,6 +627,7 @@ static void __init early_cmdline_parse(v > >>> /* Option vector 3: processor options supported */ > >>> #define OV3_FP 0x80 /* floating point */ > >>> #define OV3_VMX 0x40 /* VMX/Altivec */ > >>> +#define OV3_DFP 0x20 /* decimal floating point */ > >> > >> Can we make the flag OV3_DECFP to distinguish it from Double FP. > > > > One thing OV3_DFP has going for it is that is matches the nomenclature > > used by GCC, binutils. I'm not sure what you mean by Double FP, > > unless > > you're referring to the double wide FP unit on the Blue Gene/L 440 > > processor, but they don't refer to it as Double FP. > > I'm referring to plain old double precision floating point. The e500 > core from Freescale has version that provide embedded single > precision floating point (EFP_SINGLE) and versions that provide both > embedded double precision floating point (EFP_DOUBLE). I just want > use to be clear the DFP could mean either double or decimal as far as > I'm concerned. the comment on the #define "/* decimal floating point */" should be sufficient for that clarification tho, right? > > Also, I think the 602 (may have never seen the light of day) only > implemented single precision floating point. > > - k > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@ozlabs.org > https://ozlabs.org/mailman/listinfo/linuxppc-dev