From mboxrd@z Thu Jan 1 00:00:00 1970 From: Darius Augulis Date: Sun, 24 Oct 2010 23:22:43 +0300 Subject: [U-Boot] [PATCH] arm1176: fix relocation In-Reply-To: <20101024200813.26588.91315.stgit@darius-desktop> References: <20101024200813.26588.91315.stgit@darius-desktop> Message-ID: <4CC49593.9010106@gmail.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 10/24/2010 11:08 PM, Darius Augulis wrote: > Fix relocation code for arm1176, do it like other ARM > CPU's are doing. > Tested only with CONFIG_SKIP_RELOCATE_UBOOT defined > and using nand_spl (booting from nand). Test done on > s3c6410 based board (not yet supported in main line). > > Signed-off-by: Darius Augulis > --- > arch/arm/cpu/arm1176/start.S | 139 +++++++++++++++++++++++---------------- > arch/arm/cpu/arm1176/u-boot.lds | 15 +++- > 2 files changed, 94 insertions(+), 60 deletions(-) > > diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S > index 24e5bf4..0d733f7 100644 > --- a/arch/arm/cpu/arm1176/start.S > +++ b/arch/arm/cpu/arm1176/start.S > @@ -115,44 +115,52 @@ _armboot_start: > > /* > * These are defined in the board-specific linker script. > + * Subtracting _start from them lets the linker put their > + * relative position in the executable instead of leaving > + * them null. > */ > -.globl _bss_start > -_bss_start: > - .word __bss_start > > -.globl _bss_end > -_bss_end: > - .word _end > +.globl _bss_start_ofs > +_bss_start_ofs: > + .word __bss_start - _start > > -#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) > -/* IRQ stack memory (calculated at run-time) + 8 bytes */ > -.globl IRQ_STACK_START_IN > -IRQ_STACK_START_IN: > - .word 0x0badc0de > +.globl _bss_end_ofs > +_bss_end_ofs: > + .word _end - _start > + > +.globl _datarel_start_ofs > +_datarel_start_ofs: > + .word __datarel_start - _start > > -.globl _datarel_start > -_datarel_start: > - .word __datarel_start > +.globl _datarelrolocal_start_ofs > +_datarelrolocal_start_ofs: > + .word __datarelrolocal_start - _start > > -.globl _datarelrolocal_start > -_datarelrolocal_start: > - .word __datarelrolocal_start > +.globl _datarellocal_start_ofs > +_datarellocal_start_ofs: > + .word __datarellocal_start - _start > > -.globl _datarellocal_start > -_datarellocal_start: > - .word __datarellocal_start > +.globl _datarelro_start_ofs > +_datarelro_start_ofs: > + .word __datarelro_start - _start > > -.globl _datarelro_start > -_datarelro_start: > - .word __datarelro_start > +.globl _rel_dyn_start_ofs > +_rel_dyn_start_ofs: > + .word __rel_dyn_start - _start > > -.globl _got_start > -_got_start: > - .word __got_start > +.globl _rel_dyn_end_ofs > +_rel_dyn_end_ofs: > + .word __rel_dyn_end - _start > > -.globl _got_end > -_got_end: > - .word __got_end > +.globl _dynsym_start_ofs > +_dynsym_start_ofs: > + .word __dynsym_start - _start > + > +#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) > +/* IRQ stack memory (calculated at run-time) + 8 bytes */ > +.globl IRQ_STACK_START_IN > +IRQ_STACK_START_IN: > + .word 0x0badc0de > > /* > * the actual reset code > @@ -274,9 +282,8 @@ stack_setup: > > adr r0, _start > ldr r2, _TEXT_BASE > - ldr r3, _bss_start > - sub r2, r3, r2 /* r2<- size of armboot */ > - add r2, r0, r2 /* r2<- source end address */ > + ldr r3, _bss_start_ofs > + add r2, r0, r3 /* r2<- source end address */ > cmp r0, r6 > beq clear_bss > > @@ -288,24 +295,44 @@ copy_loop: > blo copy_loop > > #ifndef CONFIG_PRELOADER > - /* fix got entries */ > - ldr r1, _TEXT_BASE /* Text base */ > - mov r0, r7 /* reloc addr */ > - ldr r2, _got_start /* addr in Flash */ > - ldr r3, _got_end /* addr in Flash */ > - sub r3, r3, r1 > - add r3, r3, r0 > - sub r2, r2, r1 > - add r2, r2, r0 > - > + /* > + * fix .rel.dyn relocations > + */ > + ldr r0, _TEXT_BASE /* r0<- Text base */ > + sub r9, r7, r0 /* r9<- relocation offset */ > + ldr r10, _dynsym_start_ofs /* r10<- sym table ofs */ > + add r10, r10, r0 /* r10<- sym table in FLASH */ > + ldr r2, _rel_dyn_start_ofs /* r2<- rel dyn start ofs */ > + add r2, r2, r0 /* r2<- rel dyn start in FLASH */ > + ldr r3, _rel_dyn_end_ofs /* r3<- rel dyn end ofs */ > + add r3, r3, r0 /* r3<- rel dyn end in FLASH */ > fixloop: > - ldr r4, [r2] > - sub r4, r4, r1 > - add r4, r4, r0 > - str r4, [r2] > - add r2, r2, #4 > + ldr r0, [r2] /* r0<- location to fix up, IN FLASH! */ > + add r0, r9 /* r0<- location to fix up in RAM */ > + ldr r1, [r2, #4] > + and r8, r1, #0xff > + cmp r8, #23 /* relative fixup? */ > + beq fixrel > + cmp r8, #2 /* absolute fixup? */ > + beq fixabs > + /* ignore unknown type of fixup */ > + b fixnext > +fixabs: > + /* absolute fix: set location to (offset) symbol value */ > + mov r1, r1, LSR #4 /* r1<- symbol index in .dynsym */ > + add r1, r10, r1 /* r1<- address of symbol in table */ > + ldr r1, [r1, #4] /* r1<- symbol value */ > + add r1, r9 /* r1<- relocated sym addr */ > + b fixnext > +fixrel: > + /* relative fix: increase location by offset */ > + ldr r1, [r0] > + add r1, r1, r9 > +fixnext: > + str r1, [r0] > + add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ > cmp r2, r3 > - bne fixloop > + ble fixloop > #endif > #endif /* #ifndef CONFIG_SKIP_RELOCATE_UBOOT */ > > @@ -349,13 +376,11 @@ skip_hw_init: > > clear_bss: > #ifndef CONFIG_PRELOADER > - ldr r0, _bss_start > - ldr r1, _bss_end > + ldr r0, _bss_start_ofs > + ldr r1, _bss_end_ofs > ldr r3, _TEXT_BASE /* Text base */ > mov r4, r7 /* reloc addr */ > - sub r0, r0, r3 > add r0, r0, r4 > - sub r1, r1, r3 > add r1, r1, r4 > mov r2, #0x00000000 /* clear */ > > @@ -377,10 +402,9 @@ clbss_l:str r2, [r0] /* clear loop... */ > > _nand_boot: .word nand_boot > #else > - ldr r0, _TEXT_BASE > - ldr r2, _board_init_r > - sub r2, r2, r0 > - add r2, r2, r7 /* position from board_init_r in RAM */ > + ldr r0, _board_init_r_ofs > + adr r1, _start > + add r2, r0, r1 RFC: I've observed that other ARM CPU's are adding r9 to lr here (add lr, r0, r9). Even though r9 is not pre-loaded with any value in case CONFIG_SKIP_RELOCATE_UBOOT is defined. Is it bug or not? Maybe it's not tested without CONFIG_SKIP_RELOCATE_UBOOT? I've removed this line because uboot stops booting if it's there. Any comments about it? > /* setup parameters for board_init_r */ > mov r0, r5 /* gd_t */ > mov r1, r7 /* dest_addr */ > @@ -388,7 +412,8 @@ _nand_boot: .word nand_boot > mov lr, r2 > mov pc, lr > > -_board_init_r: .word board_init_r > +_board_init_r_ofs: > + .word board_init_r - _start > #endif > > #else /* #if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC) */ > diff --git a/arch/arm/cpu/arm1176/u-boot.lds b/arch/arm/cpu/arm1176/u-boot.lds > index fa640ee..d9ed954 100644 > --- a/arch/arm/cpu/arm1176/u-boot.lds > +++ b/arch/arm/cpu/arm1176/u-boot.lds > @@ -51,11 +51,14 @@ SECTIONS > *(.data.rel.ro) > } > > - __got_start = .; > . = ALIGN(4); > - .got : { *(.got) } > + __rel_dyn_start = .; > + .rel.dyn : { *(.rel.dyn) } > + __rel_dyn_end = .; > + > + __dynsym_start = .; > + .dynsym : { *(.dynsym) } > > - __got_end = .; > . = .; > __u_boot_cmd_start = .; > .u_boot_cmd : { *(.u_boot_cmd) } > @@ -65,4 +68,10 @@ SECTIONS > __bss_start = .; > .bss (NOLOAD) : { *(.bss) . = ALIGN(4); } > _end = .; > + > + /DISCARD/ : { *(.dynstr*) } > + /DISCARD/ : { *(.dynamic*) } > + /DISCARD/ : { *(.plt*) } > + /DISCARD/ : { *(.interp*) } > + /DISCARD/ : { *(.gnu*) } > }