arm1176: fix relocation

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 <augulis.darius@gmail.com>

diff --git a/arch/arm/cpu/arm1176/start.S b/arch/arm/cpu/arm1176/start.S
index c13ccebf895fa256608eab4f5eea185f8d114088..7f32db787423d05d381be3b95020cf7f184b5aa9 100644 (file)
--- a/arch/arm/cpu/arm1176/start.S
+++ b/arch/arm/cpu/arm1176/start.S
@@ -116,44 +116,52 @@ _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
-_datarel_start:
-       .word __datarel_start
+.globl _datarel_start_ofs
+_datarel_start_ofs:
+       .word __datarel_start - _start
 
-.globl _datarelrolocal_start
-_datarelrolocal_start:
-       .word __datarelrolocal_start
+.globl _datarelrolocal_start_ofs
+_datarelrolocal_start_ofs:
+       .word __datarelrolocal_start - _start
 
-.globl _datarellocal_start
-_datarellocal_start:
-       .word __datarellocal_start
+.globl _datarellocal_start_ofs
+_datarellocal_start_ofs:
+       .word __datarellocal_start - _start
 
-.globl _datarelro_start
-_datarelro_start:
-       .word __datarelro_start
+.globl _datarelro_start_ofs
+_datarelro_start_ofs:
+       .word __datarelro_start - _start
 
-.globl _got_start
-_got_start:
-       .word __got_start
+.globl _rel_dyn_start_ofs
+_rel_dyn_start_ofs:
+       .word __rel_dyn_start - _start
 
-.globl _got_end
-_got_end:
-       .word __got_end
+.globl _rel_dyn_end_ofs
+_rel_dyn_end_ofs:
+       .word __rel_dyn_end - _start
+
+.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
@@ -275,9 +283,8 @@ 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
 
@@ -289,24 +296,44 @@ 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, 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, 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
+       blo     fixloop
 #endif
 #endif /* #ifndef CONFIG_SKIP_RELOCATE_UBOOT */
 
@@ -350,13 +377,11 @@ 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                            */
 
@@ -378,18 +403,20 @@ 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     lr, r0, r1
+#ifndef CONFIG_SKIP_RELOCATE_UBOOT
+       add     lr, lr, r9
+#endif
        /* setup parameters for board_init_r */
        mov     r0, r5          /* gd_t */
        mov     r1, r7          /* dest_addr */
        /* jump to it ... */
-       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 fa640eec200648fb81f42942b2a6961fb87483df..d9ed95405d848784b6e50eadcb51bfba0e08f36e 100644 (file)
--- 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*) }
 }