SPDX: Convert all of our single license tags to Linux Kernel style

[platform/kernel/u-boot.git] / arch / arm / lib / relocate_64.S

diff --git a/arch/arm/lib/relocate_64.S b/arch/arm/lib/relocate_64.S
index 5c51cae..171d094 100644 (file)
--- a/arch/arm/lib/relocate_64.S
+++ b/arch/arm/lib/relocate_64.S
@@ -1,15 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
 /*
  * relocate - common relocation function for AArch64 U-Boot
  *
  * (C) Copyright 2013
  * Albert ARIBAUD <albert.u.boot@aribaud.net>
  * David Feng <fenghua@phytium.com.cn>
- *
- * SPDX-License-Identifier:    GPL-2.0+
  */
 
 #include <asm-offsets.h>
 #include <config.h>
+#include <elf.h>
 #include <linux/linkage.h>
 #include <asm/macro.h>
 
@@ -26,11 +26,24 @@ ENTRY(relocate_code)
        /*
         * Copy u-boot from flash to RAM
         */
-       ldr     x1, =__image_copy_start /* x1 <- SRC &__image_copy_start */
-       subs    x9, x0, x1              /* x9 <- relocation offset */
+       adr     x1, __image_copy_start  /* x1 <- Run &__image_copy_start */
+       subs    x9, x0, x1              /* x8 <- Run to copy offset */
        b.eq    relocate_done           /* skip relocation */
-       ldr     x2, =__image_copy_end   /* x2 <- SRC &__image_copy_end */
+       /*
+        * Don't ldr x1, __image_copy_start here, since if the code is already
+        * running at an address other than it was linked to, that instruction
+        * will load the relocated value of __image_copy_start. To
+        * correctly apply relocations, we need to know the linked value.
+        *
+        * Linked &__image_copy_start, which we know was at
+        * CONFIG_SYS_TEXT_BASE, which is stored in _TEXT_BASE, as a non-
+        * relocated value, since it isn't a symbol reference.
+        */
+       ldr     x1, _TEXT_BASE          /* x1 <- Linked &__image_copy_start */
+       subs    x9, x0, x1              /* x9 <- Link to copy offset */
 
+       adr     x1, __image_copy_start  /* x1 <- Run &__image_copy_start */
+       adr     x2, __image_copy_end    /* x2 <- Run &__image_copy_end */
 copy_loop:
        ldp     x10, x11, [x1], #16     /* copy from source address [x1] */
        stp     x10, x11, [x0], #16     /* copy to   target address [x0] */
@@ -41,13 +54,13 @@ copy_loop:
        /*
         * Fix .rela.dyn relocations
         */
-       ldr     x2, =__rel_dyn_start    /* x2 <- SRC &__rel_dyn_start */
-       ldr     x3, =__rel_dyn_end      /* x3 <- SRC &__rel_dyn_end */
+       adr     x2, __rel_dyn_start     /* x2 <- Run &__rel_dyn_start */
+       adr     x3, __rel_dyn_end       /* x3 <- Run &__rel_dyn_end */
 fixloop:
        ldp     x0, x1, [x2], #16       /* (x0,x1) <- (SRC location, fixup) */
        ldr     x4, [x2], #8            /* x4 <- addend */
        and     x1, x1, #0xffffffff
-       cmp     x1, #1027               /* relative fixup? */
+       cmp     x1, #R_AARCH64_RELATIVE
        bne     fixnext
 
        /* relative fix: store addend plus offset at dest location */
@@ -67,11 +80,11 @@ relocate_done:
        b       0f
 1:     mrs     x0, sctlr_el1
 0:     tbz     w0, #2, 5f      /* skip flushing cache if disabled */
-       tbz     w0, #12, 4f     /* invalide i-cache is enabled */
+       tbz     w0, #12, 4f     /* skip invalidating i-cache if disabled */
        ic      iallu           /* i-cache invalidate all */
        isb     sy
 4:     ldp     x0, x1, [sp, #16]
        bl      __asm_flush_dcache_range
-5:     ldp     x29, x30, [sp],#16
+5:     ldp     x29, x30, [sp],#32
        ret
 ENDPROC(relocate_code)