1 files changed, 42 insertions, 0 deletions

diff --git a/utils/hwstub/stub/pp/crt0.S b/utils/hwstub/stub/pp/crt0.S
new file mode 100644
index 0000000000..38b6f18ac5
--- /dev/null
+++ b/utils/hwstub/stub/pp/crt0.S
@@ -0,0 +1,42 @@
+.section    .text,"ax",%progbits
+.code       32
+.align      0x04
+.global     start
+start:
+    sub     r7, pc, #8 /* Copy running address */
+    msr     cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ/FIQ */
+    /* The stub could be located at a virtual address so killing the MMU at
+     * this point would be mere suicide. We assume that the remap location
+     * is identically mapped and kill the MMU after the copy */
+
+    /* Relocate to right address */
+    mov    r2, r7
+    ldr    r3, =_copystart
+    ldr    r4, =_copyend
+1:
+    cmp     r4, r3
+    ldrhi   r5, [r2], #4
+    strhi   r5, [r3], #4
+    bhi     1b
+    mov     r2, #0
+    mcr     p15, 0, r2, c7, c5, 0   @ Invalidate ICache
+    /* Jump to real location */
+    ldr     pc, =remap
+remap:
+    /* Disable MMU, disable caching and buffering;
+     * use low exception range address */
+    mrc     p15, 0, r0, c1, c0, 0
+    ldr     r1, =0x3005
+    bic     r0, r1
+    mcr     p15, 0, r0, c1, c0, 0
+    /* clear bss */
+    ldr     r2, =bss_start
+    ldr     r3, =bss_end
+    mov     r4, #0
+1:
+    cmp     r3, r2
+    strhi   r4, [r2], #4
+    bhi     1b
+    /* jump to C code */
+    ldr     sp, =oc_stackend
+    b       main