ARM: 6750/1: improvements to compressed/head.S (6d7d0ae5) · Commits · e / devices / android_kernel_oneplus_sm7250

arch/arm/boot/compressed/head.S

+110 −129

Original line number	Original line	Diff line number	Diff line
	@@ -174,9 +174,7 @@ not_angel:
	*/		*/

	.text		.text
	adr r0, LC0
	ldmia r0, {r1, r2, r3, r5, r6, r11, ip}
	ldr sp, [r0, #28]
	#ifdef CONFIG_AUTO_ZRELADDR		#ifdef CONFIG_AUTO_ZRELADDR
	@ determine final kernel image address		@ determine final kernel image address
	mov r4, pc		mov r4, pc
	@@ -185,35 +183,108 @@ not_angel:
	#else		#else
	ldr r4, =zreladdr		ldr r4, =zreladdr
	#endif		#endif
	subs r0, r0, r1 @ calculate the delta offset

	@ if delta is zero, we are		bl cache_on
	beq not_relocated @ running at the address we
	@ were linked at.		restart: adr r0, LC0
			ldmia r0, {r1, r2, r3, r5, r6, r9, r11, r12}
			ldr sp, [r0, #32]

			/*
			* We might be running at a different address. We need
			* to fix up various pointers.
			*/
			sub r0, r0, r1 @ calculate the delta offset
			add r5, r5, r0 @ _start
			add r6, r6, r0 @ _edata

			#ifndef CONFIG_ZBOOT_ROM
			/* malloc space is above the relocated stack (64k max) */
			add sp, sp, r0
			add r10, sp, #0x10000
			#else
			/*
			* With ZBOOT_ROM the bss/stack is non relocatable,
			* but someone could still run this code from RAM,
			* in which case our reference is _edata.
			*/
			mov r10, r6
			#endif

			/*
			* Check to see if we will overwrite ourselves.
			* r4 = final kernel address
			* r5 = start of this image
			* r9 = size of decompressed image
			* r10 = end of this image, including bss/stack/malloc space if non XIP
			* We basically want:
			* r4 >= r10 -> OK
			* r4 + image length <= r5 -> OK
			*/
			cmp r4, r10
			bhs wont_overwrite
			add r10, r4, r9
			cmp r10, r5
			bls wont_overwrite

			/*
			* Relocate ourselves past the end of the decompressed kernel.
			* r5 = start of this image
			* r6 = _edata
			* r10 = end of the decompressed kernel
			* Because we always copy ahead, we need to do it from the end and go
			* backward in case the source and destination overlap.
			*/
			/* Round up to next 256-byte boundary. */
			add r10, r10, #256
			bic r10, r10, #255

			sub r9, r6, r5 @ size to copy
			add r9, r9, #31 @ rounded up to a multiple
			bic r9, r9, #31 @ ... of 32 bytes
			add r6, r9, r5
			add r9, r9, r10

			1: ldmdb r6!, {r0 - r3, r10 - r12, lr}
			cmp r6, r5
			stmdb r9!, {r0 - r3, r10 - r12, lr}
			bhi 1b

			/* Preserve offset to relocated code. */
			sub r6, r9, r6

			bl cache_clean_flush

			adr r0, BSYM(restart)
			add r0, r0, r6
			mov pc, r0

			wont_overwrite:
	/*		/*
	* We're running at a different address. We need to fix		* If delta is zero, we are running at the address we were linked at.
	* up various pointers:		* r0 = delta
	* r5 - zImage base address (_start)		* r2 = BSS start
	* r6 - size of decompressed image		* r3 = BSS end
	* r11 - GOT start		* r4 = kernel execution address
	* ip - GOT end		* r7 = architecture ID
			* r8 = atags pointer
			* r11 = GOT start
			* r12 = GOT end
			* sp = stack pointer
	*/		*/
	add r5, r5, r0		teq r0, #0
			beq not_relocated
	add r11, r11, r0		add r11, r11, r0
	add ip, ip, r0		add r12, r12, r0

	#ifndef CONFIG_ZBOOT_ROM		#ifndef CONFIG_ZBOOT_ROM
	/*		/*
	* If we're running fully PIC === CONFIG_ZBOOT_ROM = n,		* If we're running fully PIC === CONFIG_ZBOOT_ROM = n,
	* we need to fix up pointers into the BSS region.		* we need to fix up pointers into the BSS region.
	* r2 - BSS start		* Note that the stack pointer has already been fixed up.
	* r3 - BSS end
	* sp - stack pointer
	*/		*/
	add r2, r2, r0		add r2, r2, r0
	add r3, r3, r0		add r3, r3, r0
	add sp, sp, r0

	/*		/*
	* Relocate all entries in the GOT table.		* Relocate all entries in the GOT table.
	@@ -221,7 +292,7 @@ not_angel:
	1: ldr r1, [r11, #0] @ relocate entries in the GOT		1: ldr r1, [r11, #0] @ relocate entries in the GOT
	add r1, r1, r0 @ table. This fixes up the		add r1, r1, r0 @ table. This fixes up the
	str r1, [r11], #4 @ C references.		str r1, [r11], #4 @ C references.
	cmp r11, ip		cmp r11, r12
	blo 1b		blo 1b
	#else		#else

	@@ -234,7 +305,7 @@ not_angel:
	cmphs r3, r1 @ _end < entry		cmphs r3, r1 @ _end < entry
	addlo r1, r1, r0 @ table. This fixes up the		addlo r1, r1, r0 @ table. This fixes up the
	str r1, [r11], #4 @ C references.		str r1, [r11], #4 @ C references.
	cmp r11, ip		cmp r11, r12
	blo 1b		blo 1b
	#endif		#endif

	@@ -247,75 +318,23 @@ not_relocated: mov r0, #0
	blo 1b		blo 1b

	/*		/*
	* The C runtime environment should now be setup		* The C runtime environment should now be setup sufficiently.
	* sufficiently. Turn the cache on, set up some		* Set up some pointers, and start decompressing.
	* pointers, and start decompressing.
	*/
	bl cache_on

	mov r1, sp @ malloc space above stack
	add r2, sp, #0x10000 @ 64k max

	/*
	* Check to see if we will overwrite ourselves.
	* r4 = final kernel address
	* r5 = start of this image
	* r6 = size of decompressed image
	* r2 = end of malloc space (and therefore this image)
	* We basically want:
	* r4 >= r2 -> OK
	* r4 + image length <= r5 -> OK
	*/
	cmp r4, r2
	bhs wont_overwrite
	add r0, r4, r6
	cmp r0, r5
	bls wont_overwrite

	mov r5, r2 @ decompress after malloc space
	mov r0, r5
	mov r3, r7
	bl decompress_kernel

	add r0, r0, #127 + 128 @ alignment + stack
	bic r0, r0, #127 @ align the kernel length
	/*
	* r0 = decompressed kernel length
	* r1-r3 = unused
	* r4 = kernel execution address		* r4 = kernel execution address
	* r5 = decompressed kernel start
	* r7 = architecture ID		* r7 = architecture ID
	* r8 = atags pointer		* r8 = atags pointer
	* r9-r12,r14 = corrupted
	*/
	add r1, r5, r0 @ end of decompressed kernel
	adr r2, reloc_start
	ldr r3, LC1
	add r3, r2, r3
	1: ldmia r2!, {r9 - r12, r14} @ copy relocation code
	stmia r1!, {r9 - r12, r14}
	ldmia r2!, {r9 - r12, r14}
	stmia r1!, {r9 - r12, r14}
	cmp r2, r3
	blo 1b
	mov sp, r1
	add sp, sp, #128 @ relocate the stack

	bl cache_clean_flush
	ARM( add pc, r5, r0 ) @ call relocation code
	THUMB( add r12, r5, r0 )
	THUMB( mov pc, r12 ) @ call relocation code

	/*
	* We're not in danger of overwriting ourselves. Do this the simple way.
	*
	* r4 = kernel execution address
	* r7 = architecture ID
	*/		*/
	wont_overwrite: mov r0, r4		mov r0, r4
			mov r1, sp @ malloc space above stack
			add r2, sp, #0x10000 @ 64k max
	mov r3, r7		mov r3, r7
	bl decompress_kernel		bl decompress_kernel
	b call_kernel		bl cache_clean_flush
			bl cache_off
			mov r0, #0 @ must be zero
			mov r1, r7 @ restore architecture number
			mov r2, r8 @ restore atags pointer
			mov pc, r4 @ call kernel

	.align 2		.align 2
	.type LC0, #object		.type LC0, #object
	@@ -323,11 +342,11 @@ LC0: .word LC0 @ r1
	.word __bss_start @ r2		.word __bss_start @ r2
	.word _end @ r3		.word _end @ r3
	.word _start @ r5		.word _start @ r5
	.word _image_size @ r6		.word _edata @ r6
			.word _image_size @ r9
	.word _got_start @ r11		.word _got_start @ r11
	.word _got_end @ ip		.word _got_end @ ip
	.word user_stack_end @ sp		.word user_stack_end @ sp
	LC1: .word reloc_end - reloc_start
	.size LC0, . - LC0		.size LC0, . - LC0

	#ifdef CONFIG_ARCH_RPC		#ifdef CONFIG_ARCH_RPC
	@@ -353,7 +372,7 @@ params: ldr r0, =0x10000100 @ params_phys for RPC
	* On exit,		* On exit,
	* r0, r1, r2, r3, r9, r10, r12 corrupted		* r0, r1, r2, r3, r9, r10, r12 corrupted
	* This routine must preserve:		* This routine must preserve:
	* r4, r5, r6, r7, r8		* r4, r7, r8
	*/		*/
	.align 5		.align 5
	cache_on: mov r3, #8 @ cache_on function		cache_on: mov r3, #8 @ cache_on function
	@@ -550,43 +569,6 @@ __common_mmu_cache_on:
	sub pc, lr, r0, lsr #32 @ properly flush pipeline		sub pc, lr, r0, lsr #32 @ properly flush pipeline
	#endif		#endif

	/*
	* All code following this line is relocatable. It is relocated by
	* the above code to the end of the decompressed kernel image and
	* executed there. During this time, we have no stacks.
	*
	* r0 = decompressed kernel length
	* r1-r3 = unused
	* r4 = kernel execution address
	* r5 = decompressed kernel start
	* r7 = architecture ID
	* r8 = atags pointer
	* r9-r12,r14 = corrupted
	*/
	.align 5
	reloc_start: add r9, r5, r0
	sub r9, r9, #128 @ do not copy the stack
	debug_reloc_start
	mov r1, r4
	1:
	.rept 4
	ldmia r5!, {r0, r2, r3, r10 - r12, r14} @ relocate kernel
	stmia r1!, {r0, r2, r3, r10 - r12, r14}
	.endr

	cmp r5, r9
	blo 1b
	mov sp, r1
	add sp, sp, #128 @ relocate the stack
	debug_reloc_end

	call_kernel: bl cache_clean_flush
	bl cache_off
	mov r0, #0 @ must be zero
	mov r1, r7 @ restore architecture number
	mov r2, r8 @ restore atags pointer
	mov pc, r4 @ call kernel

	/*		/*
	* Here follow the relocatable cache support functions for the		* Here follow the relocatable cache support functions for the
	* various processors. This is a generic hook for locating an		* various processors. This is a generic hook for locating an
	@@ -791,7 +773,7 @@ proc_types:
	* On exit,		* On exit,
	* r0, r1, r2, r3, r9, r12 corrupted		* r0, r1, r2, r3, r9, r12 corrupted
	* This routine must preserve:		* This routine must preserve:
	* r4, r6, r7		* r4, r7, r8
	*/		*/
	.align 5		.align 5
	cache_off: mov r3, #12 @ cache_off function		cache_off: mov r3, #12 @ cache_off function
	@@ -866,7 +848,7 @@ __armv3_mmu_cache_off:
	* On exit,		* On exit,
	* r1, r2, r3, r9, r10, r11, r12 corrupted		* r1, r2, r3, r9, r10, r11, r12 corrupted
	* This routine must preserve:		* This routine must preserve:
	* r0, r4, r5, r6, r7		* r4, r6, r7, r8
	*/		*/
	.align 5		.align 5
	cache_clean_flush:		cache_clean_flush:
	@@ -1088,7 +1070,6 @@ memdump: mov r12, r0
	#endif		#endif

	.ltorg		.ltorg
	reloc_end:

	.align		.align
	.section ".stack", "aw", %nobits		.section ".stack", "aw", %nobits