I should mention I was using the gcc-m68k-linux-gnu package on Ubuntu 22.04.4, which pulled in gcc-11-m68k-linux-gnu.
I just downloaded the bootlin m68k-coldfire--uclibc--stable-2024.02-1, and tried that. It generates the proper value in the vector table (0x400 for _start). But the call to memset is still bad:
0000f5da <board_init_f_init_reserve>: f5da: 2f02 movel %d2,%sp@- f5dc: 242f 0008 movel %sp@(8),%d2 f5e0: 4878 00c0 pea c0 <_vectors+0xc0> f5e4: 42a7 clrl %sp@- f5e6: 2f02 movel %d2,%sp@- f5e8: 61ff 0001 4622 bsrl 23c0c <_etext+0x138> f5ee: 2f02 movel %d2,%sp@- f5f0: 61ff ffff ffd2 bsrl f5c4 <arch_setup_gd> f5f6: 0682 0000 00c0 addil #192,%d2 f5fc: 4fef 0010 lea %sp@(16),%sp f600: 2047 moveal %d7,%a0 f602: 2142 00a0 movel %d2,%a0@(160) f606: 241f movel %sp@+,%d2 f608: 4e75 rts
Note "bsrl 23c0c" which points beyond _etext.
On Fri, Jul 26, 2024 at 12:59 PM Fabio Estevam festevam@gmail.com wrote:
Adding the Coldfire maintainers on Cc.
On Fri, Jul 26, 2024 at 4:46 PM Peter LaDow pladow@gmail.com wrote:
After some digging it appears that this is a toolchain issue. It seems the linker fixups are sometimes not computed correctly. For example, in board_init_f_init_reserve, the object file disassembled has:
00000000 <board_init_f_init_reserve>: 0: 2f02 movel %d2,%sp@- 2: 242f 0008 movel %sp@(8),%d2 6: 4878 00c0 pea c0 <board_init_f_init_reserve+0xc0> a: 42a7 clrl %sp@- c: 2f02 movel %d2,%sp@- e: 61ff 0000 0000 bsrl 10 <board_init_f_init_reserve+0x10> 14: 2f02 movel %d2,%sp@- 16: 61ff 0000 0000 bsrl 18 <board_init_f_init_reserve+0x18> 1c: 0682 0000 00c0 addil #192,%d2 22: 4fef 0010 lea %sp@(16),%sp 26: 2047 moveal %d7,%a0 28: 2142 00a0 movel %d2,%a0@(160) 2c: 241f movel %sp@+,%d2 2e: 4e75 rts
But when I disassemble the final linked u-boot output:
0000f646 <board_init_f_init_reserve>: f646: 2f02 movel %d2,%sp@- f648: 242f 0008 movel %sp@(8),%d2 f64c: 4878 00c0 pea c0 <_vectors+0xc0> f650: 42a7 clrl %sp@- f652: 2f02 movel %d2,%sp@- f654: 61ff 0001 44da bsrl 23b30 <_etext+0x138> f65a: 2f02 movel %d2,%sp@- f65c: 61ff ffff ffd2 bsrl f630 <arch_setup_gd> f662: 0682 0000 00c0 addil #192,%d2 f668: 4fef 0010 lea %sp@(16),%sp f66c: 2047 moveal %d7,%a0 f66e: 2142 00a0 movel %d2,%a0@(160) f672: 241f movel %sp@+,%d2 f674: 4e75 rts
Note the pea c0 instruction. The object file has board_init_f_init_reserve+0xc0 as the argument, but the final linker has 0xc0, meaning board_init_f_init_reserve is being set to 0 after linking.
Also, note the first bsrl instruction, which is not setup correctly either. This is a call to memset. This points to _etext+0x138, which is not a code region Note that 0x239f8 + 0x138 = 0x23b30. But in the final uboot, memset is at 0x1f030.
In the call to memset(), objdump shows the relocation:
RELOCATION RECORDS FOR [.text.board_init_f_init_reserve]: OFFSET TYPE VALUE 00000010 R_68K_PLT32 memset 00000018 R_68K_PLT32 arch_setup_gd
So it seems only when linking outside the same compilation unit that the relocations aren't set correctly.
I'm not sure where to look for a solution. Or how to search for an answer. I've done some digging on Google, but nothing points to a clear answer. Anyone seen something similar?
To love for the sake of being loved is human, but to love for the sake of loving is angelic. -- Alphonse de Lamartine.
On Thu, Jul 25, 2024 at 14:35 Peter LaDow pladow@gmail.com wrote:
I'm trying to add support for a custom Colfire based board. I have things building, but the final linked vectors in start.S do not point to _start. In start.S I have:
_vectors: .long 0x00000000 /* Flash offset is 0 until we setup CS0 */ .long _START
.long _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT .long _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT .long _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
Dumping the symbols in the final u-boot yields:
$ m68k-linux-gnu-nm -n u-boot 00000000 A __fixup_entries 00000000 A __got2_entries 00000000 t _vectors 00000400 T _start 0000047e T relocate_code 000004ae t fixloop
But then dumping the raw binary:
u-boot: file format elf32-m68k
Contents of section .text: 00000 00000000 00000000 00000516 00000516 ................ 00010 00000516 00000516 00000516 00000516 ................ 00020 00000516 00000516 00000516 00000516 ................ 00030 00000516 00000516 00000516 00000516 ................
Note at offset 4 it is 0x00000000, not 0x00000400 as I'd expect.
The final linker script has:
OUTPUT_ARCH(m68k) ENTRY(_start) SECTIONS { .text : { arch/m68k/cpu/mcf548x/start.o (.text*) . = DEFINED(env_offset) ? env_offset : .; env/embedded.o(.text*); *(.text*) }
It is difficult to search the archives, and so far I haven't found anything. Any help would be appreciated.
-- To love for the sake of being loved is human, but to love for the sake of loving is angelic. -- Alphonse de Lamartine.