[ARM] Allow r2 to be passed through the decompressor to the kernel

[linux-2.6-omap-h63xx.git] / arch / arm / boot / compressed / head.S

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 6abafb6f1844d9b82a3f74cbfcb3b77486f2e5b8..aaa47400eb9c19ce57a60731f81ca0b14addb1b3 100644 (file)
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -84,7 +84,7 @@
                kputc   #'\n'
                kphex   r5, 8           /* decompressed kernel start */
                kputc   #'-'
-               kphex   r8, 8           /* decompressed kernel end  */
+               kphex   r9, 8           /* decompressed kernel end  */
                kputc   #'>'
                kphex   r4, 8           /* kernel execution address */
                kputc   #'\n'
@@ -116,7 +116,7 @@ start:
                .word   start                   @ absolute load/run zImage address
                .word   _edata                  @ zImage end address
 1:             mov     r7, r1                  @ save architecture ID
-               mov     r8, #0                  @ save r0
+               mov     r8, r2                  @ save atags pointer
 
 #ifndef __ARM_ARCH_2__
                /*
@@ -144,7 +144,7 @@ not_angel:
 
                /*
                 * some architecture specific code can be inserted
-                * by the linker here, but it should preserve r7 and r8.
+                * by the linker here, but it should preserve r7, r8, and r9.
                 */
 
                .text
@@ -249,16 +249,17 @@ not_relocated:    mov     r0, #0
  * r5     = decompressed kernel start
  * r6     = processor ID
  * r7     = architecture ID
- * r8-r14 = unused
+ * r8     = atags pointer
+ * r9-r14 = corrupted
  */
                add     r1, r5, r0              @ end of decompressed kernel
                adr     r2, reloc_start
                ldr     r3, LC1
                add     r3, r2, r3
-1:             ldmia   r2!, {r8 - r13}         @ copy relocation code
-               stmia   r1!, {r8 - r13}
-               ldmia   r2!, {r8 - r13}
-               stmia   r1!, {r8 - r13}
+1:             ldmia   r2!, {r9 - r14}         @ copy relocation code
+               stmia   r1!, {r9 - r14}
+               ldmia   r2!, {r9 - r14}
+               stmia   r1!, {r9 - r14}
                cmp     r2, r3
                blo     1b
 
@@ -308,11 +309,12 @@ params:           ldr     r0, =params_phys
  *  r4 = kernel execution address
  *  r6 = processor ID
  *  r7 = architecture number
- *  r8 = run-time address of "start"
+ *  r8 = atags pointer
+ *  r9 = run-time address of "start"  (???)
  * On exit,
- *  r1, r2, r3, r8, r9, r12 corrupted
+ *  r1, r2, r3, r9, r10, r12 corrupted
  * This routine must preserve:
- *  r4, r5, r6, r7
+ *  r4, r5, r6, r7, r8
  */
                .align  5
 cache_on:      mov     r3, #8                  @ cache_on function
@@ -326,15 +328,15 @@ __setup_mmu:      sub     r3, r4, #16384          @ Page directory size
  * bits for the RAM area only.
  */
                mov     r0, r3
-               mov     r8, r0, lsr #18
-               mov     r8, r8, lsl #18         @ start of RAM
-               add     r9, r8, #0x10000000     @ a reasonable RAM size
+               mov     r9, r0, lsr #18
+               mov     r9, r9, lsl #18         @ start of RAM
+               add     r10, r9, #0x10000000    @ a reasonable RAM size
                mov     r1, #0x12
                orr     r1, r1, #3 << 10
                add     r2, r3, #16384
 1:             cmp     r1, r8                  @ if virt > start of RAM
                orrhs   r1, r1, #0x0c           @ set cacheable, bufferable
-               cmp     r1, r9                  @ if virt > end of RAM
+               cmp     r1, r10                 @ if virt > end of RAM
                bichs   r1, r1, #0x0c           @ clear cacheable, bufferable
                str     r1, [r0], #4            @ 1:1 mapping
                add     r1, r1, #1048576
@@ -403,26 +405,28 @@ __common_cache_on:
  * r5     = decompressed kernel start
  * r6     = processor ID
  * r7     = architecture ID
- * r8-r14 = unused
+ * r8     = atags pointer
+ * r9-r14 = corrupted
  */
                .align  5
-reloc_start:   add     r8, r5, r0
+reloc_start:   add     r9, r5, r0
                debug_reloc_start
                mov     r1, r4
 1:
                .rept   4
-               ldmia   r5!, {r0, r2, r3, r9 - r13}     @ relocate kernel
-               stmia   r1!, {r0, r2, r3, r9 - r13}
+               ldmia   r5!, {r0, r2, r3, r10 - r14}    @ relocate kernel
+               stmia   r1!, {r0, r2, r3, r10 - r14}
                .endr
 
-               cmp     r5, r8
+               cmp     r5, r9
                blo     1b
                debug_reloc_end
 
 call_kernel:   bl      cache_clean_flush
                bl      cache_off
-               mov     r0, #0
+               mov     r0, #0                  @ must be zero
                mov     r1, r7                  @ restore architecture number
+               mov     r2, r8                  @ restore atags pointer
                mov     pc, r4                  @ call kernel
 
 /*