From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH 01/14] ARM: LPC32XX: Initial architecture header files Date: Tue, 9 Feb 2010 17:58:57 +0000 Message-ID: <20100209175857.GA20924@n2100.arm.linux.org.uk> References: <1265674295-23996-1-git-send-email-wellsk40@gmail.com> <1265674295-23996-2-git-send-email-wellsk40@gmail.com> <20100209093129.GA2284@pengutronix.de> <20100209095934.GA11534@n2100.arm.linux.org.uk> <20100209165223.GA11113@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from caramon.arm.linux.org.uk ([78.32.30.218]:54925 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754995Ab0BIR7O (ORCPT ); Tue, 9 Feb 2010 12:59:14 -0500 Content-Disposition: inline In-Reply-To: <20100209165223.GA11113@pengutronix.de> Sender: linux-sparse-owner@vger.kernel.org List-Id: linux-sparse@vger.kernel.org To: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Cc: linux-arm-kernel@lists.infradead.org, wellsk40@gmail.com, linux-sparse@vger.kernel.org On Tue, Feb 09, 2010 at 05:52:23PM +0100, Uwe Kleine-K=F6nig wrote: > [Added linux-sparse@vger.kernel.org to Cc:] >=20 > On Tue, Feb 09, 2010 at 09:59:34AM +0000, Russell King - ARM Linux wr= ote: > > On Tue, Feb 09, 2010 at 10:31:29AM +0100, Uwe Kleine-K=F6nig wrote: > > > > +#define io_p2v(x) ((void __iomem *) (unsigned long) IO_ADDRESS= (x)) > > > Is this cast to unsigned long needed? AFAIK IO_ADDRESS(x) has > > > type unsigned for x in { 0x0 ... 0xffffffff } (provided that int = uses a > > > 32 bit 2s-complement representation). If unsigned long is really > > > needed, maybe put it into the IO_ADDRESS macro? > >=20 > > int -> void __iomem * =3D sparse warning > > unsigned long -> void __iomem * =3D no sparse warning > Ah, OK, I see. But IMHO it's a poor reason to add the cast. Either > the cast is necessary/recommended or sparse is wrong. In the first c= ase > the reasoning shouldn't have to do with sparse, in the latter sparse > should be fixed. The point is that on 64-bit architectures, a pointer may be representab= le by an unsigned long, but not an int. > Is this intended? What is the preferred way to define iomem pointers= ? Define a numerical address with a UL suffix is the simplest way. -- To unsubscribe from this list: send the line "unsubscribe linux-sparse"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html