From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f180.google.com (mail-qk1-f180.google.com [209.85.222.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE4761B3950 for ; Wed, 26 Mar 2025 12:53:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742993601; cv=none; b=fFrTg4sWzwR+nqp2/8+/L/lLO+5w/3aHfbH14oueRVg8gLaduyac6VbZYRaB4FquB/uRBKOJ6suOPsQRGbkuyL8wy5ISndwUos1Yga8B/PmI7GucU+GyULvOHzRajBEm9fXWVVk+Rkhc16nZYeo6MwqB2gvnpI8+rWwGvQfs3jE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742993601; c=relaxed/simple; bh=8HHp1uBdC+4gdzNJZq59DdfqIQAiw0gMCqs4ThMiGLY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=teA549+TU/dIh9+krCXYB5vrQK7zGpT/RCziKTegtWZGO/KcqgC2ss4j6myRCEDSAEN9eTdDOnIzRN6drvMapPLFt4nmDeXlbvoDLfsK3w6/a27pX/5uoEZ3hlYNS7T+U0l39jlAkvB6nZuRVYJbDzfUNXRk5gc24PuDC3jECPc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gourry.net; spf=pass smtp.mailfrom=gourry.net; dkim=pass (2048-bit key) header.d=gourry.net header.i=@gourry.net header.b=KTur8psl; arc=none smtp.client-ip=209.85.222.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gourry.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gourry.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gourry.net header.i=@gourry.net header.b="KTur8psl" Received: by mail-qk1-f180.google.com with SMTP id af79cd13be357-7c54a9d3fcaso690177885a.2 for ; Wed, 26 Mar 2025 05:53:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gourry.net; s=google; t=1742993597; x=1743598397; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=unBBZW4o0XvmaaTwB/+3iSkpD4sIQERsLXl81RTyoyQ=; b=KTur8pslGSHJ8IVvochTjVgBVpVZpF37vPvfn4u9I+ekOv3fxfxZsYWkQW86ryGvNX YIos6QbYkPgFaPLvnd+aJpX6D7tOwq8/GLlP8j4VzktsC6z3n/MtIy99sfT9/yltPlam pRNMIGzywkBN51M+PMSB5dEsdE+9JMqwjoAUwRTmmzcb3DbHPx3nHuk7Mh24HdWPoW2j 8Imxch9Sm8o/IcVM/CCEJIExL71kutg3FWJB8ELkf0X6P5Yk5I/D8RIlviCgiTnPtqbO lh62y4N5dewBMZ77t9FkX9P590UkroY2HdRp7o5nKoNe6XPVXZURr5k4Ac/HnUH9fUIj ys1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742993597; x=1743598397; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=unBBZW4o0XvmaaTwB/+3iSkpD4sIQERsLXl81RTyoyQ=; b=lcMLN5O0JmkA8ucKnHnOSwNsohheecw5MGvF9NPP9cljqibnY53CpU48JThL2nhE5E KRz7zX9KRAxDyXP1yxbD6rAy0UvGDHZp2wcLwWViDrTrlhno/2kpzTB880w7RGeUnWuc eGlcC30mnbBroHVK3zW1Mq+EXFdXoF3pzNoUBJl0Dz1+wUh1yatVYn81EbsaCOL+PJGw H5aeKbTZfiwXWq8GUSUVxhIGZwPT1wipIrhdKIYB3ydVFN4ONhbPT6w4BIClIsExIpyX 3NJPnEBIn8DJEnH5SfirLHSCBzLuvKYoFJn9AXcPSyRFM1PdSqKa1fikhpsyVFRwkjTH VauA== X-Forwarded-Encrypted: i=1; AJvYcCWdPGpuYW8IW05vTT3yjE4eYLB8jqlSNCtylyCAub3BvrVHEagDFkcCIGIALa/YuurI+0pf1QdoUVAl3ng=@vger.kernel.org X-Gm-Message-State: AOJu0YzOmHrrdzG/iPLS5CmleNUeyVZT43aRsVxLpbQRNEkjD1GweJTa ekPrQl8iRd6QC+3khL0cm0bYgeQZqQhIpMUepeBxGwOcoYIFCMzqaCsg8bxEuBw= X-Gm-Gg: ASbGncsnYCqcCutJjsO5iI2KMabLT4TqtMoB+goeKVAup5/EpMtSf/vOPH3oCXSP5ft 6o9k3I9ih+xhUk1WKvqBNSxumPOeV0OoId26b5DQXUIYiLVdEEo3MfNco6otbPWlBSkDFEimsz0 NuvUvGfUVhjLYXhLkdeTvZXGg9p9A6BXJFK3epTy7AaU9/GI18hhD9UJvkJS/VTfdxbaggoZLHw gxhUrnslsFkoBE1xcdTmI/QSQCR7Xrh2tXf8i0yMSUjpGgZFbCz9JfZZRnzczTEqtc0Z7nMEe9M dHxNODNJF4FK63PRGw5mLWa2tTiwTtTUKCkXUc+QUvxsIRbzhwJ04g== X-Google-Smtp-Source: AGHT+IEyK007wueidBJdaxRdr4xRWmnbMteuuUEM+eIwVWK6Vpov8l7x9HZXE3tKIEMisQ/zDeiPqg== X-Received: by 2002:a05:620a:29d0:b0:7c5:3c62:804c with SMTP id af79cd13be357-7c5ba157d0amr3415424585a.21.1742993597358; Wed, 26 Mar 2025 05:53:17 -0700 (PDT) Received: from gourry-fedora-PF4VCD3F ([99.209.85.25]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7c5b92ec688sm760794885a.64.2025.03.26.05.53.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Mar 2025 05:53:16 -0700 (PDT) Date: Wed, 26 Mar 2025 08:53:14 -0400 From: Gregory Price To: Yuquan Wang Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [LSF/MM] CXL Boot to Bash - Section 4: Interleave Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Mar 26, 2025 at 05:28:00PM +0800, Yuquan Wang wrote: > > > > Notice at both the root and the host bridge, the Interleave Ways is 2. > > There are two targets at each level. The host bridge has a granularity > > of 512 to capture its parent's ways and granularity (`2*256`). > > > > Each decoder is programmed with the total number of targets (4) and the > > overall granularity (256B). > > > > Sorry, I tried to set this topology on Qemu Virt and used: > "cxl create-region -d decoder0.0 -t ram -m mem0,mem1,mem2,mem3" > > but it failed with: > "cxl region: validate_ways: Interleave ways 2 is less than number of memdevs specified: 4" > > It seems like the CFMWs IW should be 4? > It has been a while since i've interacted with QEMU's interleave stuff, but IIRC (at least back when I was working on it) most configurations had 1 device per host bridge - in which case the CFMWS IW should be 4 with each of the host bridges described in it. I'm not sure you can do multiple devices per host bridge without a switch setup. ~Gregory