FW: GCC ARM Cross Linker Problem

[Richard Earnshaw]

On Wed, 2006-08-30 at 07:45, Kanwal Preet Singh CHANANA wrote:
> Hi Richard,
> 
> I have tried the wayout suggested by you but problem still remains.
> 
> I used the following file:
> Sym.s:
> 	.global  MaskInterrupt
> 	.type    MaskInterrupt %function
> 	.equ     MaskInterrupt, 0x00c008f8
> 

No, if it's a Thumb function you need to set the bottom bit in the
address; so you need
	.equ     MaskInterrupt, 0x00c008f9

> Note: MaskInterrupt is Thumb function located at ROM address(0x00c008f8).
> 
> When my application calls this function then there is no Interworking stub
> called. Also there is no __MaskInterrupt_from_arm function present in my
> application Map file. 

That's because you didn't set the bottom bit...

R.

> Kindly check the above file & suggest a wayout.
> 
> Regards,
> Kanwal
> 
> 
> -----Original Message-----
> From: gcc-help-owner@gcc.gnu.org [mailto:gcc-help-owner@gcc.gnu.org] On
> Behalf Of Kanwal Preet Singh CHANANA
> Sent: Wednesday, August 30, 2006 9:36 AM
> To: 'Richard Earnshaw'
> Cc: vinayakbhalkar@Math.net; gcc-help@gcc.gnu.org;
> crossgcc@sources.redhat.com
> Subject: RE: FW: GCC ARM Cross Linker Problem
> 
> 
> Hi Richard,
> 
> Thanks for valuable suggestion. I will try the following to certify if Image
> is running correctly on target. 
> 
> Another thing, the symbols I am linking are in ROM. ROM code is compiled
> with ADSv1.2 & "symbols.o" was generated using "-symdefs symbols.o" option
> for armlink. Now when I link my Flash (project) code with "symbols.o" using
> ADSv1.2 or RVDSv2.2,linker generates image with no error but if I use
> GCC-ARM ,linker gives a error " symbols.o: File format not recognised". This
> occurs due to EABI differences between ADS & GCC-ARM.
> 
> As per your suggestion, one "sym.s" will be included in  project code. We
> want to use the same source code for ADS,RVDS & GCC-ARM(few changes in *.s
> files are done using perl script). This will make sources to be generic &
> compiled with above mentioned too chains.
> 
> Can I change "symbols.o" in a way so that GCC-ARM linker recognises it ? In
> this way I don’t have to add "sym.s" file.
> 
> Regards,
> Kanwal
> 
> -----Original Message-----
> From: Richard Earnshaw [mailto:Richard.Earnshaw@arm.com] 
> Sent: Tuesday, August 29, 2006 7:54 PM
> To: Kanwal Preet Singh CHANANA
> Cc: vinayakbhalkar@Math.net; gcc-help@gcc.gnu.org;
> crossgcc@sources.redhat.com
> Subject: RE: FW: GCC ARM Cross Linker Problem
> 
> 
> The following works fine for me:
> 
> sym.s:
> 	.global	tfunc
> 	.type tfunc %function
> 	.equ	tfunc, 0x1235
> main.c:
> extern void tfunc(void);
> int main()
> {
>     tfunc();
>     return 0;
> }
> 
> arm-elf-as sym.s -o sym.o
> arm-elf-gcc main.c sym.o -o main.exe
> arm-elf-objdump -xd main.exe
> ...
> 00008224 <main>:
>     8224:       e1a0c00d        mov     ip, sp
>     8228:       e92dd800        stmdb   sp!, {fp, ip, lr, pc}
>     822c:       e24cb004        sub     fp, ip, #4      ; 0x4
>     8230:       eb0007f8        bl      a218 <__tfunc_from_arm>
>     8234:       e3a03000        mov     r3, #0  ; 0x0
>     8238:       e1a00003        mov     r0, r3
>     823c:       e89da800        ldmia   sp, {fp, sp, pc}
> ...
> 0000a218 <__tfunc_from_arm>:
>     a218:       e59fc000        ldr     ip, [pc, #0]    ; a220
> <__tfunc_from_arm
> +0x8>
>     a21c:       e12fff1c        bx      ip
>     a220:       00001235        andeq   r1, r0, r5, lsr r2
> ...
> 
> Notice that __tfunc_from_arm loads the value 0x1235 into a register and
> issues a bx instruction, which will then correctly switch to Thumb state.
> 
> R.
> 
> On Tue, 2006-08-29 at 14:47, Kanwal Preet Singh CHANANA wrote:
> > Hi Vinayak,
> > Kindly refer to below mail. I am already using this following method
> > but it is not working.
> > 
> > Regards,
> > Kanwal
> > 
> > -----Original Message-----
> > From: gcc-help-owner@gcc.gnu.org [mailto:gcc-help-owner@gcc.gnu.org]
> > On Behalf Of Vinayak Bhalkar
> > Sent: Tuesday, August 29, 2006 5:42 PM
> > To: kanwalpreet.singh@st.com
> > Cc: gcc-help@gcc.gnu.org; crossgcc@sources.redhat.com
> > Subject: Re: FW: GCC ARM Cross Linker Problem
> > 
> > 
> > 
> > Try following-
> > 
> > MaskInterrupt	=	0x00c008f9; 
> > 
> > Regards,
> > vinayak
> > 
> > --- kanwalpreet.singh@st.com wrote:
> > 
> > From: Kanwal Preet Singh CHANANA <kanwalpreet.singh@st.com>
> > To: <gcc-help@gcc.gnu.org>, <crossgcc@sources.redhat.com>
> > Subject: FW: GCC ARM Cross Linker Problem
> > Date: Tue, 29 Aug 2006 14:59:35 +0530
> > 
> > Hi all,
> > 
> > I am able to compile & Link my source files with a workaround
> > mentioned below:
> > 
> > The absolute symbols defined in symbols.o are
> > 
> > 0x000002a8 D CurTask
> > 0x00c008f8 T MaskInterrupt
> > Where Curtask is data located in RoM & MaskInterrupt is function in
> > Thumb Mode.
> > 
> > I used following definations in Linker Script
> > 
> > pCurTask		=	0x000002a8; 
> > MaskInterrupt	=	0x00c008f8; 
> > 
> > With this I am able to link & built Image.axf file. But when running
> > on target,the image crashes at a point when it jumps to 
> > MaskInterrupt(shown above) . The reason is that the Linker assumes 
> > MaskInterrupt function to be in ARM mode.When it jumps there, it 
> > expects 4 byte ARM instruction but the code at this location has 2 
> > Byte Thumb Instruction.
> > 
> > The Thumb Interwork option is enabled in Build options.
> > 
> > Can anyone suggest me a method to Link above symbols in a way so that
> > GCC-ARMv4.0.3 knows whether the symbols is Data or Thumb Function or 
> > ARM function? If there is a way, then Image will run correctly on 
> > Target. Also if anyone needs any help on Project porting from ADS to 
> > GCC-ARM,then I can help him out.
> > 
> > Please suggest a wayout to fix the above problem.
> > Regards,
> > Kanwal
> > 
> > 
> > 
> > 
> > -----Original Message-----
> > From: gcc-help-owner@gcc.gnu.org [mailto:gcc-help-owner@gcc.gnu.org]
> > On Behalf Of Kanwal Preet Singh CHANANA
> > Sent: Monday, August 21, 2006 3:48 PM
> > To: gcc-help@gcc.gnu.org
> > Subject: GCC ARM Cross Linker Problem
> > 
> > 
> > Hi all,
> > 
> > I am porting my project from ADS from ARM to GCC ARM Tool chain. I am
> > able to compile my source files but fail to link. I have a symbols file
> (symbols.o) with absolute symbols addresses in format
> > Symboladdress SymbolType Symbolname e.g
> > 
> > 0x000002a8 D CurTask
> > 0x00c008f8 T MaskInterrupt
> > 
> > These symbols are located in ROM( code built with ADS) & project image
> > will be in flash. When I use this same file during build with ARM ADS, 
> > it works fine but with GCC ARM tool chain,I get following error 
> > message
> > 
> > "./symbols.o: file not recognized: File format not recognized"
> > 
> > Can anybody please tell me the solution to this error? Can I link
> > objects built with ADS with GCC ARM ?
> > 
> > Regards,
> > Kanwal
> > 
> > 
> > 
> > _____________________________________________________________
> > Get your free web-based e-mail account from http://www.Math.net Your
> > online tourguide of Mathematics, with books, links, news, message 
> > boards, and much more!
> > 
> > 
> > --
> > For unsubscribe information see http://sourceware.org/lists.html#faq


--
For unsubscribe information see http://sourceware.org/lists.html#faq