Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755008Ab3HEVCw (ORCPT ); Mon, 5 Aug 2013 17:02:52 -0400 Received: from terminus.zytor.com ([198.137.202.10]:57294 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753367Ab3HEVCu (ORCPT ); Mon, 5 Aug 2013 17:02:50 -0400 Message-ID: <520012D4.7020701@zytor.com> Date: Mon, 05 Aug 2013 14:02:12 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130625 Thunderbird/17.0.7 MIME-Version: 1.0 To: Ondrej Zajicek CC: David Miller , dh.herrmann@gmail.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, Ondrej Zary Subject: Re: [PATCH] fbdev: suppress warning when assigning vga-save/restore base References: <1375637141-2878-1-git-send-email-dh.herrmann@gmail.com> <51FE907A.2090201@zytor.com> <20130804.185146.1621476659301936865.davem@davemloft.net> <20130805202955.GH22789@localhost> In-Reply-To: <20130805202955.GH22789@localhost> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 846 Lines: 21 On 08/05/2013 01:29 PM, Ondrej Zajicek wrote: > > How this could even work? AFAIK these cards have to be explicitly programmed > to enable MMIO (which was not done in the patches). These patches claim that > it is for multi-domain PCI. I would guess that vgabase is NULL in common > configurations but if it is non-NULL, it probably wouldn't work, unless > there is some hardware magic that transparently converts MMIO (from CPU PoV) > to port IO (from card/PCI PoV). > They presumably use iowrite/ioread, which use either I/O instructions or memory instructions depending on the address. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/