From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753920Ab1J0BkW (ORCPT ); Wed, 26 Oct 2011 21:40:22 -0400 Received: from mail2.gnudd.com ([213.203.150.91]:61519 "EHLO mail.gnudd.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752777Ab1J0BkV (ORCPT ); Wed, 26 Oct 2011 21:40:21 -0400 X-Greylist: delayed 385 seconds by postgrey-1.27 at vger.kernel.org; Wed, 26 Oct 2011 21:40:20 EDT Date: Thu, 27 Oct 2011 03:17:38 +0200 From: Alessandro Rubini To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, giancarlo.asnaghi@st.com Subject: x86/Kconfig: where to place a new chipset Message-ID: <20111027011737.GA17910@mail.gnudd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Organization: GnuDD, Device Drivers, Embedded Systems, Courses Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello. I'm currently working on a PCIe chipset (or IO-Hub), called STA2X11. The device hosts a number of peripherals (sata, ether, spi, uart, ...) and a DMA controller. The individual PCI functions can't be enabled by themselves, as chip support must be activated first. This is both because some internal mappings must be setup and because internal device functions rely on the internal DMA engine. Actually, an instance of swiotlb is being used. While I'm sure core code should be in arch/x86/platform (and there is where I placed the initialization code), I'm wondering where should the device fall in the Kconfig tree. I tend to put it in the X86_32_NON_STANDARD stanza, even if the resulting kernel will also work on standard computers (the "SGI Visual Workstation" config option does the same). On the other hand, the device can either be the core chipset (main use case) or it can be plugged on a PCIe board. Any suggestion is welcome about Kconfig placement. Being a "vi .config" and "make oldconfig" kind of guy, I can't really understand the manu layout, so I'm finding a hard time in making a sensible choice. thanks /alessandro