Fixed MTP to work with TWRP

arch/cris/boot/compressed/head_v32.S

@@ -0,0 +1,145 @@
+/*
+ *  Code that sets up the DRAM registers, calls the
+ *  decompressor to unpack the piggybacked kernel, and jumps.
+ *
+ *  Copyright (C) 1999 - 2006, Axis Communications AB
+ */
+
+#define ASSEMBLER_MACROS_ONLY
+#include <hwregs/asm/reg_map_asm.h>
+#include <mach/startup.inc>
+
+#define RAM_INIT_MAGIC 0x56902387
+#define COMMAND_LINE_MAGIC 0x87109563
+
+	;; Exported symbols
+
+	.globl	input_data
+
+	.text
+start:
+	di
+
+	;; Start clocks for used blocks.
+	START_CLOCKS
+
+	;; Initialize the DRAM registers.
+	cmp.d	RAM_INIT_MAGIC, $r8	; Already initialized?
+	beq	dram_init_finished
+	nop
+
+#if defined CONFIG_ETRAXFS
+#include "../../arch-v32/mach-fs/dram_init.S"
+#elif defined CONFIG_CRIS_MACH_ARTPEC3
+#include "../../arch-v32/mach-a3/dram_init.S"
+#else
+#error Only ETRAXFS and ARTPEC-3 supported!
+#endif
+
+dram_init_finished:
+
+	GIO_INIT
+	;; Setup the stack to a suitably high address.
+	;; We assume 8 MB is the minimum DRAM and put
+	;; the SP at the top for now.
+
+	move.d	0x40800000, $sp
+
+	;; Figure out where the compressed piggyback image is.
+	;; It is either in [NOR] flash (we don't want to copy it
+	;; to DRAM before unpacking), or copied to DRAM
+	;; by the [NAND] flash boot loader.
+	;; The piggyback image is at _edata, but relative to where the
+	;; image is actually located in memory, not where it is linked
+	;; (the decompressor is linked at 0x40700000+ and runs there).
+	;; Use (_edata - herami) as offset to the current PC.
+
+hereami:
+	lapcq	., $r5		; get PC
+	and.d	0x7fffffff, $r5	; strip any non-cache bit
+	move.d	$r5, $r0	; source address of 'herami'
+	add.d	_edata, $r5
+	sub.d	hereami, $r5	; r5 = flash address of '_edata'
+	move.d	hereami, $r1	; destination
+
+	;; Copy text+data to DRAM
+
+	move.d	_edata, $r2	; end destination
+1:	move.w	[$r0+], $r3	; from herami+ source
+	move.w	$r3, [$r1+]	; to hereami+ destination (linked address)
+	cmp.d	$r2, $r1	; finish when destination == _edata
+	bcs	1b
+	nop
+	move.d	input_data, $r0 ; for the decompressor
+	move.d	$r5, [$r0]	; 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, $r0
+	move.d  $r10, [$r0]
+	move.d	_cmd_line_addr, $r0
+	move.d  $r11, [$r0]
+
+	;;  Save boot source indicator
+	move.d	_boot_source, $r0
+	move.d	$r12, [$r0]
+
+	;; Do the decompression and save compressed size in _inptr
+
+	jsr	decompress_kernel
+	nop
+
+	;; Restore boot source indicator
+	move.d	_boot_source, $r12
+	move.d	[$r12], $r12
+
+	;; 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
+
+	;; Put start address of root partition in r9 so the kernel can use it
+	;; when mounting from flash
+	move.d  input_data, $r0
+	move.d	[$r0], $r9		; flash address of compressed kernel
+	move.d  inptr, $r0
+	add.d	[$r0], $r9		; size of compressed kernel
+	cmp.d   0x40000000, $r9		; image in DRAM ?
+	blo	enter_kernel		; no, must be [NOR] flash, jump
+	nop				; delay slot
+	and.d   0x001fffff, $r9		; assume compressed kernel was < 2M
+
+enter_kernel:
+	;; Enter the decompressed kernel
+	move.d	RAM_INIT_MAGIC, $r8	; Tell kernel that DRAM is initialized
+	jump	0x40004000	; kernel is linked to this address
+	nop
+
+	.data
+
+input_data:
+	.dword	0		; used by the decompressor
+_cmd_line_magic:
+	.dword 0
+_cmd_line_addr:
+	.dword 0
+_boot_source:
+	.dword 0
+
+#if defined CONFIG_ETRAXFS
+#include "../../arch-v32/mach-fs/hw_settings.S"
+#elif defined CONFIG_CRIS_MACH_ARTPEC3
+#include "../../arch-v32/mach-a3/hw_settings.S"
+#else
+#error Only ETRAXFS and ARTPEC-3 supported!
+#endif