From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 89E8EBA39; Sat, 22 Jun 2024 17:52:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719078727; cv=none; b=HgqmWKf+IYjzKSKHobri4Z3fbu/qLVzD8rFaZrPDl4t8umLW1KMlSgJvS/iWIOjU4AuorcMBm4eDmILCZyqeNBGD/Ol3mPrtChLevhka4EWl78PUXMSDavG/qwSSjG/nWOlobS+WXHJb4vQ5nTufnwDFeNuZQZ3GRcVJCeMvdUk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719078727; c=relaxed/simple; bh=TgcQO5cI1N99h+gDcZZc8jr7775wxXCMauMmVkr4DYU=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=Xy4j+5AYG36xxnlJ32NVveQyHGzeO0zZ+sLW+9s5qmL/by1x+6Kxc1rsIrqL+LhuyXCjxzmy/DHXkTfLkQr9GkwaK81qtqHPZ+eU0VRMCEZSfhBAnw4+L6Yg7oOA8whvtnnjN2v5iOnJGMjKOfn9+g7Po7EsakSQDIwcLl5BH+0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fSs+V+DZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fSs+V+DZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EFA39C3277B; Sat, 22 Jun 2024 17:52:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719078727; bh=TgcQO5cI1N99h+gDcZZc8jr7775wxXCMauMmVkr4DYU=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=fSs+V+DZS83pyGpwyU8XOItV98rDKi8EQAxj13OsY3oXv4O4LONKnVidDIhcu6Jqy SG21le8JZhXy7ys/2wt2Ig2DFvyS2g5DBEWVoSSbETYb2KnoH1TNfAn5AHHOq82iLq 7KHLFS3OXcxBh9bACZWctL5URdqqWB8vnbY7D/trWGqHQLQWaN5XIMKOZ5k/LVk9US FSuOUMWBarcFIYAx3OwoW7eOf4OesKe2gZ2YUW/Hot42mOkThSQK8vXcjH66U8AeO8 DUuivg0zbBs223qvftuh+poPP+HfnMNxT0OweC1D8pHGgQkVFfyhYyTXROjEoQGRiM GNAZu7JKEratQ== Date: Sat, 22 Jun 2024 12:52:05 -0500 From: Bjorn Helgaas To: "zhoushengqing@ttyinfo.com" Cc: Bjorn Helgaas , linux-pci , linux-kernel Subject: Re: Re: [PATCH] PCI: Enable io space 1k granularity for intel cpu root port Message-ID: <20240622175205.GA1432837@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@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: <2024062223061743562815@ttyinfo.com> On Sat, Jun 22, 2024 at 11:06:18PM +0800, zhoushengqing@ttyinfo.com wrote: > >> This patch add 1k granularity for intel root port bridge.Intel latest > > > > >> server CPU support 1K granularity,And there is an BIOS setup item named > > > I don't know what your email agent is doing to add all these extra blank lines, but it makes it painful to read/reply: https://lore.kernel.org/all/2024062223061743562815@ttyinfo.com/ > >Can you implement this as a quirk similar to quirk_p64h2_1k_io()? > > > >I don't want to clutter the generic code with device-specific > >things like this. > > I have attempted to implement this patch in quirks.c.But there > doesn't seem to be a suitable DECLARE_PCI_FIXUP* to do this.because > the patch is not targeting the device itself, It targets other P2P > devices with the same bus number. If I understand the patch correctly, if a [8086:09a2] device on a root bus has EN1K set, *every* bridge (every Root Port in this case because I assume this is a PCIe configuration) on the same bus supports 1K granularity? That seems like a really broken kind of encapsulation. I'd be surprised if there were not a bit in each of those Root Ports that indicates this.