243 lines
		
	
	
	
		
			4.1 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
		
		
			
		
	
	
			243 lines
		
	
	
	
		
			4.1 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
|   | /* | ||
|  |  * This file is subject to the terms and conditions of the GNU General Public | ||
|  |  * License.  See the file "COPYING" in the main directory of this archive | ||
|  |  * for more details. | ||
|  |  * | ||
|  |  * Quick'n'dirty IP checksum ... | ||
|  |  * | ||
|  |  * Copyright (C) 1998, 1999 Ralf Baechle | ||
|  |  * Copyright (C) 1999 Silicon Graphics, Inc. | ||
|  |  */ | ||
|  | #include <asm/asm.h> | ||
|  | #include <asm/regdef.h> | ||
|  | 
 | ||
|  | #define ADDC(sum,reg)						\ | ||
|  | 	addu	sum, reg;					\
 | ||
|  | 	sltu	v1, sum, reg;					\
 | ||
|  | 	addu	sum, v1 | ||
|  | 
 | ||
|  | #define CSUM_BIGCHUNK(src, offset, sum, t0, t1, t2, t3)		\ | ||
|  | 	lw	t0, (offset + 0x00)(src);			\
 | ||
|  | 	lw	t1, (offset + 0x04)(src);			\
 | ||
|  | 	lw	t2, (offset + 0x08)(src); 			\
 | ||
|  | 	lw	t3, (offset + 0x0c)(src); 			\
 | ||
|  | 	ADDC(sum, t0);						\
 | ||
|  | 	ADDC(sum, t1);						\
 | ||
|  | 	ADDC(sum, t2);						\
 | ||
|  | 	ADDC(sum, t3);						\
 | ||
|  | 	lw	t0, (offset + 0x10)(src);			\
 | ||
|  | 	lw	t1, (offset + 0x14)(src);			\
 | ||
|  | 	lw	t2, (offset + 0x18)(src);			\
 | ||
|  | 	lw	t3, (offset + 0x1c)(src);			\
 | ||
|  | 	ADDC(sum, t0);						\
 | ||
|  | 	ADDC(sum, t1);						\
 | ||
|  | 	ADDC(sum, t2);						\
 | ||
|  | 	ADDC(sum, t3);						\
 | ||
|  | 
 | ||
|  | /* | ||
|  |  * a0: source address | ||
|  |  * a1: length of the area to checksum | ||
|  |  * a2: partial checksum | ||
|  |  */ | ||
|  | 
 | ||
|  | #define src a0 | ||
|  | #define sum v0 | ||
|  | 
 | ||
|  | 	.text | ||
|  | 	.set	noreorder
 | ||
|  | 
 | ||
|  | /* unknown src alignment and < 8 bytes to go  */ | ||
|  | small_csumcpy: | ||
|  | 	move	a1, ta2 | ||
|  | 
 | ||
|  | 	andi	ta0, a1, 4 | ||
|  | 	beqz	ta0, 1f | ||
|  | 	 andi	ta0, a1, 2 | ||
|  | 
 | ||
|  | 	/* Still a full word to go  */ | ||
|  | 	ulw	ta1, (src) | ||
|  | 	daddiu	src, 4 | ||
|  | 	ADDC(sum, ta1) | ||
|  | 
 | ||
|  | 1:	move	ta1, zero | ||
|  | 	beqz	ta0, 1f | ||
|  | 	 andi	ta0, a1, 1 | ||
|  | 
 | ||
|  | 	/* Still a halfword to go  */ | ||
|  | 	ulhu	ta1, (src) | ||
|  | 	daddiu	src, 2 | ||
|  | 
 | ||
|  | 1:	beqz	ta0, 1f | ||
|  | 	 sll	ta1, ta1, 16 | ||
|  | 
 | ||
|  | 	lbu	ta2, (src) | ||
|  | 	 nop | ||
|  | 
 | ||
|  | #ifdef __MIPSEB__ | ||
|  | 	sll	ta2, ta2, 8 | ||
|  | #endif | ||
|  | 	or	ta1, ta2 | ||
|  | 
 | ||
|  | 1:	ADDC(sum, ta1) | ||
|  | 
 | ||
|  | 	/* fold checksum */ | ||
|  | 	sll	v1, sum, 16 | ||
|  | 	addu	sum, v1 | ||
|  | 	sltu	v1, sum, v1 | ||
|  | 	srl	sum, sum, 16 | ||
|  | 	addu	sum, v1 | ||
|  | 
 | ||
|  | 	/* odd buffer alignment? */ | ||
|  | 	beqz	t3, 1f | ||
|  | 	 nop | ||
|  | 	sll	v1, sum, 8 | ||
|  | 	srl	sum, sum, 8 | ||
|  | 	or	sum, v1 | ||
|  | 	andi	sum, 0xffff | ||
|  | 1: | ||
|  | 	.set	reorder
 | ||
|  | 	/* Add the passed partial csum.  */ | ||
|  | 	ADDC(sum, a2) | ||
|  | 	jr	ra | ||
|  | 	.set	noreorder
 | ||
|  | 
 | ||
|  | /* ------------------------------------------------------------------------- */ | ||
|  | 
 | ||
|  | 	.align	5
 | ||
|  | LEAF(csum_partial) | ||
|  | 	move	sum, zero | ||
|  | 	move	t3, zero | ||
|  | 
 | ||
|  | 	sltiu	t8, a1, 0x8 | ||
|  | 	bnez	t8, small_csumcpy		/* < 8 bytes to copy */ | ||
|  | 	 move	ta2, a1 | ||
|  | 
 | ||
|  | 	beqz	a1, out | ||
|  | 	 andi	t3, src, 0x1			/* odd buffer? */ | ||
|  | 
 | ||
|  | hword_align: | ||
|  | 	beqz	t3, word_align | ||
|  | 	 andi	t8, src, 0x2 | ||
|  | 
 | ||
|  | 	lbu	ta0, (src) | ||
|  | 	dsubu	a1, a1, 0x1 | ||
|  | #ifdef __MIPSEL__ | ||
|  | 	sll	ta0, ta0, 8 | ||
|  | #endif | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	daddu	src, src, 0x1 | ||
|  | 	andi	t8, src, 0x2 | ||
|  | 
 | ||
|  | word_align: | ||
|  | 	beqz	t8, dword_align | ||
|  | 	 sltiu	t8, a1, 56 | ||
|  | 
 | ||
|  | 	lhu	ta0, (src) | ||
|  | 	dsubu	a1, a1, 0x2 | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	sltiu	t8, a1, 56 | ||
|  | 	daddu	src, src, 0x2 | ||
|  | 
 | ||
|  | dword_align: | ||
|  | 	bnez	t8, do_end_words | ||
|  | 	 move	t8, a1 | ||
|  | 
 | ||
|  | 	andi	t8, src, 0x4 | ||
|  | 	beqz	t8, qword_align | ||
|  | 	 andi	t8, src, 0x8 | ||
|  | 
 | ||
|  | 	lw	ta0, 0x00(src) | ||
|  | 	dsubu	a1, a1, 0x4 | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	daddu	src, src, 0x4 | ||
|  | 	andi	t8, src, 0x8 | ||
|  | 
 | ||
|  | qword_align: | ||
|  | 	beqz	t8, oword_align | ||
|  | 	 andi	t8, src, 0x10 | ||
|  | 
 | ||
|  | 	lw	ta0, 0x00(src) | ||
|  | 	lw	ta1, 0x04(src) | ||
|  | 	dsubu	a1, a1, 0x8 | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	ADDC(sum, ta1) | ||
|  | 	daddu	src, src, 0x8 | ||
|  | 	andi	t8, src, 0x10 | ||
|  | 
 | ||
|  | oword_align: | ||
|  | 	beqz	t8, begin_movement | ||
|  | 	 dsrl	t8, a1, 0x7 | ||
|  | 
 | ||
|  | 	lw	ta3, 0x08(src) | ||
|  | 	lw	t0, 0x0c(src) | ||
|  | 	lw	ta0, 0x00(src) | ||
|  | 	lw	ta1, 0x04(src) | ||
|  | 	ADDC(sum, ta3) | ||
|  | 	ADDC(sum, t0) | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	ADDC(sum, ta1) | ||
|  | 	dsubu	a1, a1, 0x10 | ||
|  | 	daddu	src, src, 0x10 | ||
|  | 	dsrl	t8, a1, 0x7 | ||
|  | 
 | ||
|  | begin_movement: | ||
|  | 	beqz	t8, 1f | ||
|  | 	 andi	ta2, a1, 0x40 | ||
|  | 
 | ||
|  | move_128bytes: | ||
|  | 	CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0) | ||
|  | 	CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0) | ||
|  | 	CSUM_BIGCHUNK(src, 0x40, sum, ta0, ta1, ta3, t0) | ||
|  | 	CSUM_BIGCHUNK(src, 0x60, sum, ta0, ta1, ta3, t0) | ||
|  | 	dsubu	t8, t8, 0x01 | ||
|  | 	bnez	t8, move_128bytes | ||
|  | 	 daddu	src, src, 0x80 | ||
|  | 
 | ||
|  | 1: | ||
|  | 	beqz	ta2, 1f | ||
|  | 	 andi	ta2, a1, 0x20 | ||
|  | 
 | ||
|  | move_64bytes: | ||
|  | 	CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0) | ||
|  | 	CSUM_BIGCHUNK(src, 0x20, sum, ta0, ta1, ta3, t0) | ||
|  | 	daddu	src, src, 0x40 | ||
|  | 
 | ||
|  | 1: | ||
|  | 	beqz	ta2, do_end_words | ||
|  | 	 andi	t8, a1, 0x1c | ||
|  | 
 | ||
|  | move_32bytes: | ||
|  | 	CSUM_BIGCHUNK(src, 0x00, sum, ta0, ta1, ta3, t0) | ||
|  | 	andi	t8, a1, 0x1c | ||
|  | 	daddu	src, src, 0x20 | ||
|  | 
 | ||
|  | do_end_words: | ||
|  | 	beqz	t8, maybe_end_cruft | ||
|  | 	 dsrl	t8, t8, 0x2 | ||
|  | 
 | ||
|  | end_words: | ||
|  | 	lw	ta0, (src) | ||
|  | 	dsubu	t8, t8, 0x1 | ||
|  | 	ADDC(sum, ta0) | ||
|  | 	bnez	t8, end_words | ||
|  | 	 daddu	src, src, 0x4 | ||
|  | 
 | ||
|  | maybe_end_cruft: | ||
|  | 	andi	ta2, a1, 0x3 | ||
|  | 
 | ||
|  | small_memcpy: | ||
|  |  j small_csumcpy; move a1, ta2		/* XXX ??? */
 | ||
|  | 	beqz	t2, out | ||
|  | 	 move	a1, ta2 | ||
|  | 
 | ||
|  | end_bytes: | ||
|  | 	lb	ta0, (src) | ||
|  | 	dsubu	a1, a1, 0x1 | ||
|  | 	bnez	a2, end_bytes | ||
|  | 	 daddu	src, src, 0x1 | ||
|  | 
 | ||
|  | out: | ||
|  | 	jr	ra | ||
|  | 	 move	v0, sum | ||
|  | 	END(csum_partial) |