From mboxrd@z Thu Jan 1 00:00:00 1970 From: York Sun Date: Mon, 7 Dec 2015 09:33:45 -0800 Subject: [U-Boot] [PATCH 3/5] Data type defined for pointer addresses In-Reply-To: <1449508442.15946.60.camel@freescale.com> References: <1447911713-28639-1-git-send-email-aneesh.bansal@freescale.com> <1447911713-28639-3-git-send-email-aneesh.bansal@freescale.com> <5665B8D4.2070206@freescale.com> <20151207170858.GI9551@bill-the-cat> <1449508442.15946.60.camel@freescale.com> Message-ID: <5665C2F9.7000507@freescale.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 12/07/2015 09:14 AM, Scott Wood wrote: > On Mon, 2015-12-07 at 12:08 -0500, Tom Rini wrote: >> On Mon, Dec 07, 2015 at 08:50:28AM -0800, York Sun wrote: >>> Guys, >>> >>> Please comment on this new typedef. I am not comfortable to accept it. >>> >>> On 11/18/2015 09:41 PM, Aneesh Bansal wrote: >>>> A new data type uintptr_t has been defined for creating >>>> pointers (32 or 64 bit depending on Core) from 32 bit variables >>>> storing the address. >>>> If a 32 bit variable (u32) is typecasted to a pointer (void *), >>>> compiler gives a warning in case size of pointer on the core is 64 bit. >>>> >>>> Signed-off-by: Aneesh Bansal >>>> --- >>>> arch/arm/include/asm/types.h | 2 ++ >>>> arch/powerpc/include/asm/types.h | 1 + >>>> 2 files changed, 3 insertions(+) >>>> >>>> diff --git a/arch/arm/include/asm/types.h b/arch/arm/include/asm/types.h >>>> index 388058e..5555765 100644 >>>> --- a/arch/arm/include/asm/types.h >>>> +++ b/arch/arm/include/asm/types.h >>>> @@ -56,6 +56,8 @@ typedef unsigned long phys_addr_t; >>>> typedef unsigned long phys_size_t; >>>> #endif >>>> >>>> +typedef unsigned long uintptr_t; >>> >>> It is used in next patch of this series >>> http://patchwork.ozlabs.org/patch/552669/, in two-step casting such as >>> >>> (u8 *)(uintptr_t)csf_hdr_addr >>> >>> As OP indicated, the variable is u32. Casting to a pointer causes >>> compiling >>> warning. Is this the right approach? >> >> Approach is OK. But please do it as a "backport" of 142956af from the >> linux kernel which adds 142956af to so everyone has it. > > There's also an existing uintptr_t typedef in include/compiler.h... > Tom, We seem not having the abuse of ptrdiff_t. So the equivalent of Linux commit 142956af would be moving this typedef from include/compiler.h to include/linux/types.h. York