]> git.kernelconcepts.de Git - karo-tx-uboot.git/blobdiff - arch/arm/cpu/arm926ejs/start.S
arm: fixloop(): do not use r8 for relocation
[karo-tx-uboot.git] / arch / arm / cpu / arm926ejs / start.S
index cf40ce12928359c5238d02a32ed361ccc153c101..6c49c830f2bdcea7ffdf7ecf465cc795ad9bd49b 100644 (file)
@@ -10,6 +10,7 @@
  *  Copyright (c) 2002 Gary Jennejohn <garyj@denx.de>
  *  Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
  *  Copyright (c) 2003 Kshitij <kshitij@ti.com>
+ *  Copyright (c) 2010 Albert Aribaud <albert.aribaud@free.fr>
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -30,7 +31,7 @@
  * MA 02111-1307 USA
  */
 
-
+#include <asm-offsets.h>
 #include <config.h>
 #include <common.h>
 #include <version.h>
@@ -114,23 +115,23 @@ _fiq:
  *************************************************************************
  */
 
+.globl _TEXT_BASE
 _TEXT_BASE:
-       .word   TEXT_BASE
-
-.globl _armboot_start
-_armboot_start:
-       .word _start
+       .word   CONFIG_SYS_TEXT_BASE
 
 /*
  * 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_start_ofs
+_bss_start_ofs:
+       .word __bss_start - _start
 
-.globl _bss_end
-_bss_end:
-       .word _end
+.globl _bss_end_ofs
+_bss_end_ofs:
+       .word _end - _start
 
 #ifdef CONFIG_USE_IRQ
 /* IRQ stack memory (calculated at run-time) */
@@ -144,6 +145,10 @@ FIQ_STACK_START:
        .word 0x0badc0de
 #endif
 
+/* IRQ stack memory (calculated at run-time) + 8 bytes */
+.globl IRQ_STACK_START_IN
+IRQ_STACK_START_IN:
+       .word   0x0badc0de
 
 /*
  * the actual reset code
@@ -166,62 +171,137 @@ reset:
        bl      cpu_init_crit
 #endif
 
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-relocate:                              /* relocate U-Boot to RAM           */
-       adr     r0, _start              /* r0 <- current position of code   */
-       ldr     r1, _TEXT_BASE          /* test if we run from flash or RAM */
-       cmp     r0, r1                  /* don't reloc during debug         */
-       beq     stack_setup
-       ldr     r2, _armboot_start
-       ldr     r3, _bss_start
-       sub     r2, r3, r2              /* r2 <- size of armboot            */
-       add     r2, r0, r2              /* r2 <- source end address         */
+/* Set stackpointer in internal RAM to call board_init_f */
+call_board_init_f:
+       ldr     sp, =(CONFIG_SYS_INIT_SP_ADDR)
+       bic     sp, sp, #7 /* 8-byte alignment for ABI compliance */
+       ldr     r0,=0x00000000
+       bl      board_init_f
 
-copy_loop:
-       ldmia   r0!, {r3-r10}           /* copy from source address [r0]    */
-       stmia   r1!, {r3-r10}           /* copy to   target address [r1]    */
-       cmp     r0, r2                  /* until source end addreee [r2]    */
-       ble     copy_loop
-#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
+/*------------------------------------------------------------------------------*/
+
+/*
+ * void relocate_code (addr_sp, gd, addr_moni)
+ *
+ * This "function" does not return, instead it continues in RAM
+ * after relocating the monitor code.
+ *
+ */
+       .globl  relocate_code
+relocate_code:
+       mov     r4, r0  /* save addr_sp */
+       mov     r5, r1  /* save addr of gd */
+       mov     r6, r2  /* save addr of destination */
 
        /* Set up the stack                                                 */
 stack_setup:
-       ldr     r0, _TEXT_BASE          /* upper 128 KiB: relocated uboot   */
-       sub     sp, r0, #128            /* leave 32 words for abort-stack   */
+       mov     sp, r4
+
+       adr     r0, _start
+       cmp     r0, r6
+       beq     clear_bss               /* skip relocation */
+       mov     r1, r6                  /* r1 <- scratch for copy loop */
+       ldr     r2, _TEXT_BASE
+       ldr     r3, _bss_start_ofs
+       add     r2, r0, r3              /* r2 <- source end address         */
+
+copy_loop:
+       ldmia   r0!, {r9-r10}           /* copy from source address [r0]    */
+       stmia   r1!, {r9-r10}           /* copy to   target address [r1]    */
+       cmp     r0, r2                  /* until source end address [r2]    */
+       blo     copy_loop
+
 #ifndef CONFIG_PRELOADER
-       sub     r0, r0, #CONFIG_SYS_MALLOC_LEN  /* malloc area                      */
-       sub     r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo                        */
-#ifdef CONFIG_USE_IRQ
-       sub     r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
+       /*
+        * fix .rel.dyn relocations
+        */
+       ldr     r0, _TEXT_BASE          /* r0 <- Text base */
+       sub     r9, r6, 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     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     r7, r1, #0xff
+       cmp     r7, #23                 /* relative fixup? */
+       beq     fixrel
+       cmp     r7, #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
+       blo     fixloop
 #endif
-#endif /* CONFIG_PRELOADER */
-       sub     sp, r0, #12             /* leave 3 words for abort-stack    */
-       bic     sp, sp, #7              /* 8-byte alignment for ABI compliance */
 
 clear_bss:
-       ldr     r0, _bss_start          /* find start of bss segment        */
-       ldr     r1, _bss_end            /* stop here                        */
-       mov     r2, #0x00000000         /* clear                            */
-
 #ifndef CONFIG_PRELOADER
-clbss_l:str    r2, [r0]                /* clear loop...                    */
+       ldr     r0, _bss_start_ofs
+       ldr     r1, _bss_end_ofs
+       ldr     r3, _TEXT_BASE          /* Text base */
+       mov     r4, r6                  /* reloc addr */
+       add     r0, r0, r4
+       add     r1, r1, r4
+       mov     r2, #0x00000000         /* clear                            */
+
+clbss_l:str    r2, [r0]                /* clear loop...                    */
        add     r0, r0, #4
        cmp     r0, r1
-       ble     clbss_l
+       bne     clbss_l
 
        bl coloured_LED_init
        bl red_LED_on
-#endif /* CONFIG_PRELOADER */
-
-       ldr     pc, _start_armboot
+#endif
 
-_start_armboot:
+/*
+ * We are done. Do not return, instead branch to second part of board
+ * initialization, now running from RAM.
+ */
 #ifdef CONFIG_NAND_SPL
+       ldr     r0, _nand_boot_ofs
+       mov     pc, r0
+
+_nand_boot_ofs:
        .word nand_boot
 #else
-       .word start_armboot
-#endif /* CONFIG_NAND_SPL */
+       ldr     r0, _board_init_r_ofs
+       adr     r1, _start
+       add     lr, r0, r1
+       add     lr, lr, r9
+       /* setup parameters for board_init_r */
+       mov     r0, r5          /* gd_t */
+       mov     r1, r6          /* dest_addr */
+       /* jump to it ... */
+       mov     pc, lr
+
+_board_init_r_ofs:
+       .word board_init_r - _start
+#endif
 
+_rel_dyn_start_ofs:
+       .word __rel_dyn_start - _start
+_rel_dyn_end_ofs:
+       .word __rel_dyn_end - _start
+_dynsym_start_ofs:
+       .word __dynsym_start - _start
 
 /*
  *************************************************************************
@@ -307,10 +387,7 @@ cpu_init_crit:
        @ carve out a frame on current user stack
        sub     sp, sp, #S_FRAME_SIZE
        stmia   sp, {r0 - r12}  @ Save user registers (now in svc mode) r0-r12
-
-       ldr     r2, _armboot_start
-       sub     r2, r2, #(CONFIG_STACKSIZE+CONFIG_SYS_MALLOC_LEN)
-       sub     r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8)  @ set base 2 words into abort stack
+       ldr     r2, IRQ_STACK_START_IN
        @ get values for "aborted" pc and cpsr (into parm regs)
        ldmia   r2, {r2 - r3}
        add     r0, sp, #S_FRAME_SIZE           @ grab pointer to old stack
@@ -342,9 +419,7 @@ cpu_init_crit:
        .endm
 
        .macro get_bad_stack
-       ldr     r13, _armboot_start             @ setup our mode stack
-       sub     r13, r13, #(CONFIG_STACKSIZE+CONFIG_SYS_MALLOC_LEN)
-       sub     r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE+8) @ reserved a couple spots in abort stack
+       ldr     r13, IRQ_STACK_START_IN         @ setup our mode stack
 
        str     lr, [r13]       @ save caller lr in position 0 of saved stack
        mrs     lr, spsr        @ get the spsr