[U-Boot-Users] printf with u-boot-1.1.2

[U-Boot-Users] printf with u-boot-1.1.2

[Shakthi Kannan]

Greetings!

I am using u-boot-1.1.2 with CodeSourcery's 3.4.3
cross-toolchain for ARM on the Versatile PB-ARM926EJ-S
board.

u-boot compiles fine. The hello_world.c in examples/
compiles fine. From the given example, I have removed
all statements except the printf statement. It
compiles fine.

I load it address 04000000 (SDRAM on board, top bank).
I execute it using "go 04000000", it runs and exits
with rc=0x0. But, I don't see the printf string being
printed. Only one character gets printed. I am
wondering if printf uses \r after every character gets
printed, so it basically overwrites. 

I am able to display a character, using putc(). getc()
also works fine. These work if I load it a SDRAM
address, say, 0x05000000, and give the entry point as
05000000 itself (go 05000000). But, the documentation
mentions offset 0x4 as entry point.

I'd appreciate any feedback on what I am doing wrong
and how I can get the printf working.

Thanks,

SK

--
Shakthi Kannan, MS
Software Engineer, Specsoft (Hexaware Technologies)
[E]: shakthimaan at yahoo.com           [M]: (91) 98407-87007
[W]: http://www.shakthimaan.com      [L]: Chennai, India


	
		
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[U-Boot-Users] printf with u-boot-1.1.2

[Andrew Wozniak]

Andrew Wozniak  |  Mercury Computer Systems
978.967.1895    |  System SW, ICS Group


Shakthi Kannan wrote:
> Greetings!
> 
> I am using u-boot-1.1.2 with CodeSourcery's 3.4.3
> cross-toolchain for ARM on the Versatile PB-ARM926EJ-S
> board.
> 
> u-boot compiles fine. The hello_world.c in examples/
> compiles fine. From the given example, I have removed
> all statements except the printf statement. It
> compiles fine.
> 
> I load it address 04000000 (SDRAM on board, top bank).
> I execute it using "go 04000000", it runs and exits
> with rc=0x0. But, I don't see the printf string being
> printed. Only one character gets printed. I am
> wondering if printf uses \r after every character gets
> printed, so it basically overwrites. 
> 
> I am able to display a character, using putc(). getc()
> also works fine. These work if I load it a SDRAM
> address, say, 0x05000000, and give the entry point as
> 05000000 itself (go 05000000). But, the documentation
> mentions offset 0x4 as entry point.

Why not try running with the offset - works for me.

> I'd appreciate any feedback on what I am doing wrong
> and how I can get the printf working.

Assuming you compiled with -g, take a look at hello_world.o for the 
generated assembly code. See anything obvious?

$ ppc_405-objdump -S hello_world.o

hello_world.o:     file format elf32-powerpc

Disassembly of section .text:

00000000 <hello_world-0x4>:
    0:   00 00 7f e8     .long 0x7fe8

00000004 <hello_world>:

int hello_world(int argc, char *argv[])
{
    4:   94 21 fe 48     stwu    r1,-440(r1)
    8:   7c 08 02 a6     mflr    r0
    c:   be c1 01 90     stmw    r22,400(r1)
   10:   90 01 01 bc     stw     r0,444(r1)
   14:   48 00 00 05     bl      18 <hello_world.c+0x14>
   18:   7f c8 02 a6     mflr    r30
   1c:   80 1e ff e8     lwz     r0,-24(r30)
   20:   7f c0 f2 14     add     r30,r0,r30
     DECLARE_GLOBAL_DATA_PTR;

     bd_t *bd = gd->bd;
   24:   83 9d 00 00     lwz     r28,0(r29)
<snip>

> Thanks,
> 
> SK
> 
> --
> Shakthi Kannan, MS
> Software Engineer, Specsoft (Hexaware Technologies)
> [E]: shakthimaan at yahoo.com           [M]: (91) 98407-87007
> [W]: http://www.shakthimaan.com      [L]: Chennai, India
> 
> 
> 	
> 		
> __________________________________ 
> Yahoo! Mail - PC Magazine Editors' Choice 2005 
> http://mail.yahoo.com
> 
> 
> -------------------------------------------------------
> This SF.Net email is sponsored by:
> Power Architecture Resource Center: Free content, downloads, discussions,
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> https://lists.sourceforge.net/lists/listinfo/u-boot-users
> 

[U-Boot-Users] printf with u-boot-1.1.2

[Shakthi Kannan]

Hi Andrew,

Thanks for your reply.

Here is the hello_world compilation output:

make[1]: Entering directory
`/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/examples'
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-gcc -g
 -Os   -fno-strict-aliasing  -fno-common -ffixed-r8
-msoft-float -D__KERNEL__ -DTEXT_BASE=0x01000000
-I/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/include
-fno-builtin -ffreestanding -nostdinc -isystem
/usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3/include
-pipe  -DCONFIG_ARM -D__ARM__ -march=armv4 -Wall
-Wstrict-prototypes -c -o stubs.o stubs.c
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-ar crv
libstubs.a  stubs.o
a - stubs.o
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-gcc -g
 -Os   -fno-strict-aliasing  -fno-common -ffixed-r8
-msoft-float -D__KERNEL__ -DTEXT_BASE=0x01000000
-I/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/include
-fno-builtin -ffreestanding -nostdinc -isystem
/usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3/include
-pipe  -DCONFIG_ARM -D__ARM__ -march=armv4 -Wall
-Wstrict-prototypes -c -o hello_world.o hello_world.c
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-ld -g 
-Ttext 0xc100000 \
	-o hello_world -e hello_world hello_world.o
libstubs.a \

-L/usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3
-lgcc
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-objcopy
-O srec hello_world hello_world.srec 2>/dev/null
/usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-objcopy
-O binary hello_world hello_world.bin 2>/dev/null
make[1]: Leaving directory
`/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/examples'

C code
-------

#include <common.h>
#include <exports.h>

int hello_world (int argc, char *argv[])
{
  char str[] = "foobar";
  
  printf ("%s\n", str);
  return 0;
}

Disassembly code
-----------------

hello_world.o:     file format elf32-littlearm

Disassembly of section .text:

00000000 <hello_world>:
#include <exports.h>


int hello_world (int argc, char *argv[])
{
   0:	e52de004 	str	lr, [sp, #-4]!
  char str[]="foobar";
   4:	e59f302c 	ldr	r3, [pc, #44]	; 38 <.text+0x38>
   8:	e8930003 	ldmia	r3, {r0, r1}
   c:	e1a03821 	mov	r3, r1, lsr #16
  10:	e24dd00c 	sub	sp, sp, #12	; 0xc
  14:	e58d0000 	str	r0, [sp]

  printf ("%s\n", str);
  18:	e59f001c 	ldr	r0, [pc, #28]	; 3c <.text+0x3c>
  1c:	e1cd10b4 	strh	r1, [sp, #4]
  20:	e1a0100d 	mov	r1, sp
  24:	e5cd3006 	strb	r3, [sp, #6]
  28:	ebfffffe 	bl	0 <printf>
  return 0;
}
  2c:	e3a00000 	mov	r0, #0	; 0x0
  30:	e28dd00c 	add	sp, sp, #12	; 0xc
  34:	e8bd8000 	ldmia	sp!, {pc}
  38:	00000000 	andeq	r0, r0, r0
  3c:	00000008 	andeq	r0, r0, r8

I still don't get printf output. Only a single
character gets printed. Any thoughts?

Thanks,

SK


--
Shakthi Kannan, MS
Software Engineer, Specsoft (Hexaware Technologies)
[E]: shakthimaan at yahoo.com           [M]: (91) 98407-87007
[W]: http://www.shakthimaan.com      [L]: Chennai, India


		
__________________________________ 
Start your day with Yahoo! - Make it your home page! 
http://www.yahoo.com/r/hs

[U-Boot-Users] printf with u-boot-1.1.2

[Andrew Wozniak]

I'm not familiar with the ARM platform, but in general, this compile 
looks ok.

Shakthi Kannan wrote:
> Hi Andrew,
> 
> Thanks for your reply.
> 
> Here is the hello_world compilation output:
> 
> make[1]: Entering directory
> `/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/examples'
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-gcc -g
>  -Os   -fno-strict-aliasing  -fno-common -ffixed-r8
> -msoft-float -D__KERNEL__ -DTEXT_BASE=0x01000000

-DTEXT_BASE=0x01000000 is where U-Boot should be installed.

> -I/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/include
> -fno-builtin -ffreestanding -nostdinc -isystem
> /usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3/include
> -pipe  -DCONFIG_ARM -D__ARM__ -march=armv4 -Wall
> -Wstrict-prototypes -c -o stubs.o stubs.c
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-ar crv
> libstubs.a  stubs.o
> a - stubs.o
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-gcc -g
>  -Os   -fno-strict-aliasing  -fno-common -ffixed-r8
> -msoft-float -D__KERNEL__ -DTEXT_BASE=0x01000000
> -I/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/include
> -fno-builtin -ffreestanding -nostdinc -isystem
> /usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3/include
> -pipe  -DCONFIG_ARM -D__ARM__ -march=armv4 -Wall
> -Wstrict-prototypes -c -o hello_world.o hello_world.c
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-ld -g 
> -Ttext 0xc100000 \

-Ttext 0xc100000 is the "load" and "run" address of hello_world.

Forget about the 0x4 offset mentioned in the docs, it is for PPC only.

> 	-o hello_world -e hello_world hello_world.o
> libstubs.a \
> 
> -L/usr/local/arm/3.4.3/bin/../lib/gcc/arm-none-linux-gnueabi/3.4.3
> -lgcc
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-objcopy
> -O srec hello_world hello_world.srec 2>/dev/null
> /usr/local/arm/3.4.3/bin/arm-none-linux-gnueabi-objcopy
> -O binary hello_world hello_world.bin 2>/dev/null
> make[1]: Leaving directory
> `/home/shaks/docs/monitor/u-boot/u-boot-1.1.2/examples'
> 
> C code
> -------
> 
> #include <common.h>
> #include <exports.h>
> 
> int hello_world (int argc, char *argv[])
> {
>   char str[] = "foobar";
>   

     app_startup(argv);

The original hello_world source code and doc/README.standalone says that 
app_startup() is required for proper access to imported functions, such 
as printf().

>   printf ("%s\n", str);
>   return 0;
> }
> 
> Disassembly code
> -----------------
> 
> hello_world.o:     file format elf32-littlearm
> 
> Disassembly of section .text:
> 
> 00000000 <hello_world>:
> #include <exports.h>
> 
> 
> int hello_world (int argc, char *argv[])
> {
>    0:	e52de004 	str	lr, [sp, #-4]!
>   char str[]="foobar";
>    4:	e59f302c 	ldr	r3, [pc, #44]	; 38 <.text+0x38>
>    8:	e8930003 	ldmia	r3, {r0, r1}
>    c:	e1a03821 	mov	r3, r1, lsr #16
>   10:	e24dd00c 	sub	sp, sp, #12	; 0xc
>   14:	e58d0000 	str	r0, [sp]
> 
>   printf ("%s\n", str);
>   18:	e59f001c 	ldr	r0, [pc, #28]	; 3c <.text+0x3c>
>   1c:	e1cd10b4 	strh	r1, [sp, #4]
>   20:	e1a0100d 	mov	r1, sp
>   24:	e5cd3006 	strb	r3, [sp, #6]
>   28:	ebfffffe 	bl	0 <printf>
>   return 0;
> }
>   2c:	e3a00000 	mov	r0, #0	; 0x0
>   30:	e28dd00c 	add	sp, sp, #12	; 0xc
>   34:	e8bd8000 	ldmia	sp!, {pc}
>   38:	00000000 	andeq	r0, r0, r0
>   3c:	00000008 	andeq	r0, r0, r8
> 
> I still don't get printf output. Only a single
> character gets printed. Any thoughts?
> 
> Thanks,
> 
> SK
> 
> 
> --
> Shakthi Kannan, MS
> Software Engineer, Specsoft (Hexaware Technologies)
> [E]: shakthimaan at yahoo.com           [M]: (91) 98407-87007
> [W]: http://www.shakthimaan.com      [L]: Chennai, India
> 
> 
> 		
> __________________________________ 
> Start your day with Yahoo! - Make it your home page! 
> http://www.yahoo.com/r/hs
> 
> 
> -------------------------------------------------------
> This SF.Net email is sponsored by:
> Power Architecture Resource Center: Free content, downloads, discussions,
> and more. http://solutions.newsforge.com/ibmarch.tmpl
> _______________________________________________
> U-Boot-Users mailing list
> U-Boot-Users at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/u-boot-users
>