aboutsummaryrefslogtreecommitdiff
path: root/arch/cris/boot/compressed/head_v10.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/cris/boot/compressed/head_v10.S')
-rw-r--r--arch/cris/boot/compressed/head_v10.S126
1 files changed, 126 insertions, 0 deletions
diff --git a/arch/cris/boot/compressed/head_v10.S b/arch/cris/boot/compressed/head_v10.S
new file mode 100644
index 00000000000..9edb8ade7e1
--- /dev/null
+++ b/arch/cris/boot/compressed/head_v10.S
@@ -0,0 +1,126 @@
+/*
+ * arch/cris/boot/compressed/head.S
+ *
+ * Copyright (C) 1999, 2001 Axis Communications AB
+ *
+ * Code that sets up the DRAM registers, calls the
+ * decompressor to unpack the piggybacked kernel, and jumps.
+ *
+ */
+
+#define ASSEMBLER_MACROS_ONLY
+#include <arch/sv_addr_ag.h>
+
+#define RAM_INIT_MAGIC 0x56902387
+#define COMMAND_LINE_MAGIC 0x87109563
+
+ ;; Exported symbols
+
+ .globl input_data
+
+
+ .text
+
+ nop
+ di
+
+;; We need to initialze DRAM registers before we start using the DRAM
+
+ cmp.d RAM_INIT_MAGIC, $r8 ; Already initialized?
+ beq dram_init_finished
+ nop
+
+#include "../../arch-v10/lib/dram_init.S"
+
+dram_init_finished:
+
+ ;; Initiate the PA and PB ports
+
+ move.b CONFIG_ETRAX_DEF_R_PORT_PA_DATA, $r0
+ move.b $r0, [R_PORT_PA_DATA]
+
+ move.b CONFIG_ETRAX_DEF_R_PORT_PA_DIR, $r0
+ move.b $r0, [R_PORT_PA_DIR]
+
+ move.b CONFIG_ETRAX_DEF_R_PORT_PB_DATA, $r0
+ move.b $r0, [R_PORT_PB_DATA]
+
+ move.b CONFIG_ETRAX_DEF_R_PORT_PB_DIR, $r0
+ move.b $r0, [R_PORT_PB_DIR]
+
+ ;; Setup the stack to a suitably high address.
+ ;; We assume 8 MB is the minimum DRAM in an eLinux
+ ;; product and put the sp at the top for now.
+
+ move.d 0x40800000, $sp
+
+ ;; Figure out where the compressed piggyback image is
+ ;; in the flash (since we wont try to copy it to DRAM
+ ;; before unpacking). It is at _edata, but in flash.
+ ;; Use (_edata - basse) as offset to the current PC.
+
+basse: move.d $pc, $r5
+ and.d 0x7fffffff, $r5 ; strip any non-cache bit
+ subq 2, $r5 ; compensate for the move.d $pc instr
+ move.d $r5, $r0 ; save for later - flash address of 'basse'
+ add.d _edata, $r5
+ sub.d basse, $r5 ; $r5 = flash address of '_edata'
+
+ ;; Copy text+data to DRAM
+
+ move.d basse, $r1 ; destination
+ move.d _edata, $r2 ; end destination
+1: move.w [$r0+], $r3
+ move.w $r3, [$r1+]
+ cmp.d $r2, $r1
+ bcs 1b
+ nop
+
+ move.d $r5, [input_data] ; for the decompressor
+
+
+ ;; Clear the decompressors BSS (between _edata and _end)
+
+ moveq 0, $r0
+ move.d _edata, $r1
+ move.d _end, $r2
+1: move.w $r0, [$r1+]
+ cmp.d $r2, $r1
+ bcs 1b
+ nop
+
+ ;; Save command line magic and address.
+ move.d _cmd_line_magic, $r12
+ move.d $r10, [$r12]
+ move.d _cmd_line_addr, $r12
+ move.d $r11, [$r12]
+
+ ;; Do the decompression and save compressed size in inptr
+
+ jsr decompress_kernel
+
+ ;; Put start address of root partition in $r9 so the kernel can use it
+ ;; when mounting from flash
+
+ move.d [input_data], $r9 ; flash address of compressed kernel
+ add.d [inptr], $r9 ; size of compressed kernel
+
+ ;; Restore command line magic and address.
+ move.d _cmd_line_magic, $r10
+ move.d [$r10], $r10
+ move.d _cmd_line_addr, $r11
+ move.d [$r11], $r11
+
+ ;; Enter the decompressed kernel
+ move.d RAM_INIT_MAGIC, $r8 ; Tell kernel that DRAM is initialized
+ jump 0x40004000 ; kernel is linked to this address
+
+ .data
+
+input_data:
+ .dword 0 ; used by the decompressor
+_cmd_line_magic:
+ .dword 0
+_cmd_line_addr:
+ .dword 0
+#include "../../arch-v10/lib/hw_settings.S"