diff mbox

[1/4] crypto: powerpc - Factor out the core CRC vpmsum algorithm

Message ID 20170315123737.20234-1-dja@axtens.net (mailing list archive)
State Accepted
Delegated to: Herbert Xu
Headers show

Commit Message

Daniel Axtens March 15, 2017, 12:37 p.m. UTC 
The core nuts and bolts of the crc32c vpmsum algorithm will
also work for a number of other CRC algorithms with different
polynomials. Factor out the function into a new asm file.

To handle multiple users of the function, a user simply
provides constants, defines the name of their CRC function,
and then #includes the core algorithm file.

Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Daniel Axtens <dja@axtens.net>

--

It's possible at this point to argue that the address
of the constant tables should be passed in to the function,
rather than doing this somewhat unconventional #include.

However, we're about to add further #ifdef's back into the core
that will be provided by the encapsulaing code, and which couldn't
be done as a variable without performance loss.
---
 arch/powerpc/crypto/crc32-vpmsum_core.S | 726 ++++++++++++++++++++++++++++++++
 arch/powerpc/crypto/crc32c-vpmsum_asm.S | 714 +------------------------------
 2 files changed, 729 insertions(+), 711 deletions(-)
 create mode 100644 arch/powerpc/crypto/crc32-vpmsum_core.S

Comments

David Laight March 15, 2017, 4:10 p.m. UTC | #1 
From: Linuxppc-dev Daniel Axtens
> Sent: 15 March 2017 12:38
> The core nuts and bolts of the crc32c vpmsum algorithm will
> also work for a number of other CRC algorithms with different
> polynomials. Factor out the function into a new asm file.
> 
> To handle multiple users of the function, a user simply
> provides constants, defines the name of their CRC function,
> and then #includes the core algorithm file.
...

While not part of this change, the unrolled loops look as though
they just destroy the cpu cache.
I'd like be convinced that anything does CRC over long enough buffers
to make it a gain at all.

With modern (not that modern now) superscalar cpus you can often
get the loop instructions 'for free'.
Sometimes pipelining the loop is needed to get full throughput.
Unlike the IP checksum, you don't even have to 'loop carry' the
cpu carry flag.

	David
Daniel Axtens March 15, 2017, 10:30 p.m. UTC | #2 
Hi David,

> While not part of this change, the unrolled loops look as though
> they just destroy the cpu cache.
> I'd like be convinced that anything does CRC over long enough buffers
> to make it a gain at all.
>
> With modern (not that modern now) superscalar cpus you can often
> get the loop instructions 'for free'.
> Sometimes pipelining the loop is needed to get full throughput.
> Unlike the IP checksum, you don't even have to 'loop carry' the
> cpu carry flag.

Internal testing on a NVMe device with T10DIF enabled on 4k blocks
shows a 20x - 30x improvement. Without these patches, crc_t10dif_generic
uses over 60% of CPU time - with these patches CRC drops to single
digits.

I should probably have lead with that, sorry.

FWIW, the original patch showed a 3.7x gain on btrfs as well -
6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")

When Anton wrote the original code he had access to IBM's internal
tooling for looking at how instructions flow through the various stages
of the CPU, so I trust it's pretty much optimal from that point of view.

Regards,
Daniel
David Laight March 16, 2017, 9:50 a.m. UTC | #3 
From: Daniel Axtens
> Sent: 15 March 2017 22:30
> Hi David,
> 
> > While not part of this change, the unrolled loops look as though
> > they just destroy the cpu cache.
> > I'd like be convinced that anything does CRC over long enough buffers
> > to make it a gain at all.
> >
> > With modern (not that modern now) superscalar cpus you can often
> > get the loop instructions 'for free'.
> > Sometimes pipelining the loop is needed to get full throughput.
> > Unlike the IP checksum, you don't even have to 'loop carry' the
> > cpu carry flag.
> 
> Internal testing on a NVMe device with T10DIF enabled on 4k blocks
> shows a 20x - 30x improvement. Without these patches, crc_t10dif_generic
> uses over 60% of CPU time - with these patches CRC drops to single
> digits.
> 
> I should probably have lead with that, sorry.

I'm not doubting that using the cpu instruction for crcs gives a
massive performance boost.

Just that the heavily unrolled loop is unlikely to help overall.
Some 'cold cache' tests on shorter buffers might be illuminating.
 
> FWIW, the original patch showed a 3.7x gain on btrfs as well -
> 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
> 
> When Anton wrote the original code he had access to IBM's internal
> tooling for looking at how instructions flow through the various stages
> of the CPU, so I trust it's pretty much optimal from that point of view.

Doesn't mean he used it :-)

	David
Michael Ellerman March 16, 2017, 10:45 a.m. UTC | #4 
Daniel Axtens <dja@axtens.net> writes:

> The core nuts and bolts of the crc32c vpmsum algorithm will
> also work for a number of other CRC algorithms with different
> polynomials. Factor out the function into a new asm file.
>
> To handle multiple users of the function, a user simply
> provides constants, defines the name of their CRC function,
> and then #includes the core algorithm file.
>
> Cc: Anton Blanchard <anton@samba.org>
> Signed-off-by: Daniel Axtens <dja@axtens.net>
>
> --
>
> It's possible at this point to argue that the address
> of the constant tables should be passed in to the function,
> rather than doing this somewhat unconventional #include.
>
> However, we're about to add further #ifdef's back into the core
> that will be provided by the encapsulaing code, and which couldn't
> be done as a variable without performance loss.
> ---
>  arch/powerpc/crypto/crc32-vpmsum_core.S | 726 ++++++++++++++++++++++++++++++++
>  arch/powerpc/crypto/crc32c-vpmsum_asm.S | 714 +------------------------------
>  2 files changed, 729 insertions(+), 711 deletions(-)
>  create mode 100644 arch/powerpc/crypto/crc32-vpmsum_core.S

So although this sits in arch/powerpc, it's heavy on the crypto which is
not my area of expertise (to say the least!), so I think it should
probably go via Herbert and the crypto tree?

cheers
Anton Blanchard March 16, 2017, 11:13 a.m. UTC | #5 
Hi David,

> While not part of this change, the unrolled loops look as though
> they just destroy the cpu cache.
> I'd like be convinced that anything does CRC over long enough buffers
> to make it a gain at all.

btrfs data checksumming is one area.

> With modern (not that modern now) superscalar cpus you can often
> get the loop instructions 'for free'.

A branch on POWER8 is a three cycle redirect. The vpmsum instructions
are 6 cycles.

> Sometimes pipelining the loop is needed to get full throughput.
> Unlike the IP checksum, you don't even have to 'loop carry' the
> cpu carry flag.

It went through quite a lot of simulation to reach peak performance.
The loop is quite delicate, we have to pace it just right to avoid
some pipeline reject conditions.

Note also that we already modulo schedule the loop across three
iterations, required to hide the latency of the vpmsum instructions.

Anton
Daniel Axtens March 16, 2017, 12:54 p.m. UTC | #6 
> So although this sits in arch/powerpc, it's heavy on the crypto which is
> not my area of expertise (to say the least!), so I think it should
> probably go via Herbert and the crypto tree?

That was my thought as well. Sorry - probably should have put that in
the comments somewhere.

Regards,
Daniel
Herbert Xu March 24, 2017, 2:12 p.m. UTC | #7 
Daniel Axtens <dja@axtens.net> wrote:
> The core nuts and bolts of the crc32c vpmsum algorithm will
> also work for a number of other CRC algorithms with different
> polynomials. Factor out the function into a new asm file.
> 
> To handle multiple users of the function, a user simply
> provides constants, defines the name of their CRC function,
> and then #includes the core algorithm file.
> 
> Cc: Anton Blanchard <anton@samba.org>
> Signed-off-by: Daniel Axtens <dja@axtens.net>

All patches applied.  Thanks.
diff mbox

Patch

diff --git a/arch/powerpc/crypto/crc32-vpmsum_core.S b/arch/powerpc/crypto/crc32-vpmsum_core.S
new file mode 100644
index 000000000000..629244ef170e
--- /dev/null
+++ b/arch/powerpc/crypto/crc32-vpmsum_core.S
@@ -0,0 +1,726 @@ 
+/*
+ * Core of the accelerated CRC algorithm.
+ * In your file, define the constants and CRC_FUNCTION_NAME
+ * Then include this file.
+ *
+ * Calculate the checksum of data that is 16 byte aligned and a multiple of
+ * 16 bytes.
+ *
+ * The first step is to reduce it to 1024 bits. We do this in 8 parallel
+ * chunks in order to mask the latency of the vpmsum instructions. If we
+ * have more than 32 kB of data to checksum we repeat this step multiple
+ * times, passing in the previous 1024 bits.
+ *
+ * The next step is to reduce the 1024 bits to 64 bits. This step adds
+ * 32 bits of 0s to the end - this matches what a CRC does. We just
+ * calculate constants that land the data in this 32 bits.
+ *
+ * We then use fixed point Barrett reduction to compute a mod n over GF(2)
+ * for n = CRC using POWER8 instructions. We use x = 32.
+ *
+ * http://en.wikipedia.org/wiki/Barrett_reduction
+ *
+ * Copyright (C) 2015 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+*/
+	
+#include <asm/ppc_asm.h>
+#include <asm/ppc-opcode.h>
+
+#define MAX_SIZE	32768
+
+	.text
+
+#if defined(__BIG_ENDIAN__)
+#define BYTESWAP_DATA
+#else
+#undef BYTESWAP_DATA
+#endif
+
+#define off16		r25
+#define off32		r26
+#define off48		r27
+#define off64		r28
+#define off80		r29
+#define off96		r30
+#define off112		r31
+
+#define const1		v24
+#define const2		v25
+
+#define byteswap	v26
+#define	mask_32bit	v27
+#define	mask_64bit	v28
+#define zeroes		v29
+
+#ifdef BYTESWAP_DATA
+#define VPERM(A, B, C, D) vperm	A, B, C, D
+#else
+#define VPERM(A, B, C, D)
+#endif
+
+/* unsigned int CRC_FUNCTION_NAME(unsigned int crc, void *p, unsigned long len) */
+FUNC_START(CRC_FUNCTION_NAME)
+	std	r31,-8(r1)
+	std	r30,-16(r1)
+	std	r29,-24(r1)
+	std	r28,-32(r1)
+	std	r27,-40(r1)
+	std	r26,-48(r1)
+	std	r25,-56(r1)
+
+	li	off16,16
+	li	off32,32
+	li	off48,48
+	li	off64,64
+	li	off80,80
+	li	off96,96
+	li	off112,112
+	li	r0,0
+
+	/* Enough room for saving 10 non volatile VMX registers */
+	subi	r6,r1,56+10*16
+	subi	r7,r1,56+2*16
+
+	stvx	v20,0,r6
+	stvx	v21,off16,r6
+	stvx	v22,off32,r6
+	stvx	v23,off48,r6
+	stvx	v24,off64,r6
+	stvx	v25,off80,r6
+	stvx	v26,off96,r6
+	stvx	v27,off112,r6
+	stvx	v28,0,r7
+	stvx	v29,off16,r7
+
+	mr	r10,r3
+
+	vxor	zeroes,zeroes,zeroes
+	vspltisw v0,-1
+
+	vsldoi	mask_32bit,zeroes,v0,4
+	vsldoi	mask_64bit,zeroes,v0,8
+
+	/* Get the initial value into v8 */
+	vxor	v8,v8,v8
+	MTVRD(v8, R3)
+	vsldoi	v8,zeroes,v8,8	/* shift into bottom 32 bits */
+
+#ifdef BYTESWAP_DATA
+	addis	r3,r2,.byteswap_constant@toc@ha
+	addi	r3,r3,.byteswap_constant@toc@l
+
+	lvx	byteswap,0,r3
+	addi	r3,r3,16
+#endif
+
+	cmpdi	r5,256
+	blt	.Lshort
+
+	rldicr	r6,r5,0,56
+
+	/* Checksum in blocks of MAX_SIZE */
+1:	lis	r7,MAX_SIZE@h
+	ori	r7,r7,MAX_SIZE@l
+	mr	r9,r7
+	cmpd	r6,r7
+	bgt	2f
+	mr	r7,r6
+2:	subf	r6,r7,r6
+
+	/* our main loop does 128 bytes at a time */
+	srdi	r7,r7,7
+
+	/*
+	 * Work out the offset into the constants table to start at. Each
+	 * constant is 16 bytes, and it is used against 128 bytes of input
+	 * data - 128 / 16 = 8
+	 */
+	sldi	r8,r7,4
+	srdi	r9,r9,3
+	subf	r8,r8,r9
+
+	/* We reduce our final 128 bytes in a separate step */
+	addi	r7,r7,-1
+	mtctr	r7
+
+	addis	r3,r2,.constants@toc@ha
+	addi	r3,r3,.constants@toc@l
+
+	/* Find the start of our constants */
+	add	r3,r3,r8
+
+	/* zero v0-v7 which will contain our checksums */
+	vxor	v0,v0,v0
+	vxor	v1,v1,v1
+	vxor	v2,v2,v2
+	vxor	v3,v3,v3
+	vxor	v4,v4,v4
+	vxor	v5,v5,v5
+	vxor	v6,v6,v6
+	vxor	v7,v7,v7
+
+	lvx	const1,0,r3
+
+	/*
+	 * If we are looping back to consume more data we use the values
+	 * already in v16-v23.
+	 */
+	cmpdi	r0,1
+	beq	2f
+
+	/* First warm up pass */
+	lvx	v16,0,r4
+	lvx	v17,off16,r4
+	VPERM(v16,v16,v16,byteswap)
+	VPERM(v17,v17,v17,byteswap)
+	lvx	v18,off32,r4
+	lvx	v19,off48,r4
+	VPERM(v18,v18,v18,byteswap)
+	VPERM(v19,v19,v19,byteswap)
+	lvx	v20,off64,r4
+	lvx	v21,off80,r4
+	VPERM(v20,v20,v20,byteswap)
+	VPERM(v21,v21,v21,byteswap)
+	lvx	v22,off96,r4
+	lvx	v23,off112,r4
+	VPERM(v22,v22,v22,byteswap)
+	VPERM(v23,v23,v23,byteswap)
+	addi	r4,r4,8*16
+
+	/* xor in initial value */
+	vxor	v16,v16,v8
+
+2:	bdz	.Lfirst_warm_up_done
+
+	addi	r3,r3,16
+	lvx	const2,0,r3
+
+	/* Second warm up pass */
+	VPMSUMD(v8,v16,const1)
+	lvx	v16,0,r4
+	VPERM(v16,v16,v16,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v9,v17,const1)
+	lvx	v17,off16,r4
+	VPERM(v17,v17,v17,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v10,v18,const1)
+	lvx	v18,off32,r4
+	VPERM(v18,v18,v18,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v11,v19,const1)
+	lvx	v19,off48,r4
+	VPERM(v19,v19,v19,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v12,v20,const1)
+	lvx	v20,off64,r4
+	VPERM(v20,v20,v20,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v13,v21,const1)
+	lvx	v21,off80,r4
+	VPERM(v21,v21,v21,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v14,v22,const1)
+	lvx	v22,off96,r4
+	VPERM(v22,v22,v22,byteswap)
+	ori	r2,r2,0
+
+	VPMSUMD(v15,v23,const1)
+	lvx	v23,off112,r4
+	VPERM(v23,v23,v23,byteswap)
+
+	addi	r4,r4,8*16
+
+	bdz	.Lfirst_cool_down
+
+	/*
+	 * main loop. We modulo schedule it such that it takes three iterations
+	 * to complete - first iteration load, second iteration vpmsum, third
+	 * iteration xor.
+	 */
+	.balign	16
+4:	lvx	const1,0,r3
+	addi	r3,r3,16
+	ori	r2,r2,0
+
+	vxor	v0,v0,v8
+	VPMSUMD(v8,v16,const2)
+	lvx	v16,0,r4
+	VPERM(v16,v16,v16,byteswap)
+	ori	r2,r2,0
+
+	vxor	v1,v1,v9
+	VPMSUMD(v9,v17,const2)
+	lvx	v17,off16,r4
+	VPERM(v17,v17,v17,byteswap)
+	ori	r2,r2,0
+
+	vxor	v2,v2,v10
+	VPMSUMD(v10,v18,const2)
+	lvx	v18,off32,r4
+	VPERM(v18,v18,v18,byteswap)
+	ori	r2,r2,0
+
+	vxor	v3,v3,v11
+	VPMSUMD(v11,v19,const2)
+	lvx	v19,off48,r4
+	VPERM(v19,v19,v19,byteswap)
+	lvx	const2,0,r3
+	ori	r2,r2,0
+
+	vxor	v4,v4,v12
+	VPMSUMD(v12,v20,const1)
+	lvx	v20,off64,r4
+	VPERM(v20,v20,v20,byteswap)
+	ori	r2,r2,0
+
+	vxor	v5,v5,v13
+	VPMSUMD(v13,v21,const1)
+	lvx	v21,off80,r4
+	VPERM(v21,v21,v21,byteswap)
+	ori	r2,r2,0
+
+	vxor	v6,v6,v14
+	VPMSUMD(v14,v22,const1)
+	lvx	v22,off96,r4
+	VPERM(v22,v22,v22,byteswap)
+	ori	r2,r2,0
+
+	vxor	v7,v7,v15
+	VPMSUMD(v15,v23,const1)
+	lvx	v23,off112,r4
+	VPERM(v23,v23,v23,byteswap)
+
+	addi	r4,r4,8*16
+
+	bdnz	4b
+
+.Lfirst_cool_down:
+	/* First cool down pass */
+	lvx	const1,0,r3
+	addi	r3,r3,16
+
+	vxor	v0,v0,v8
+	VPMSUMD(v8,v16,const1)
+	ori	r2,r2,0
+
+	vxor	v1,v1,v9
+	VPMSUMD(v9,v17,const1)
+	ori	r2,r2,0
+
+	vxor	v2,v2,v10
+	VPMSUMD(v10,v18,const1)
+	ori	r2,r2,0
+
+	vxor	v3,v3,v11
+	VPMSUMD(v11,v19,const1)
+	ori	r2,r2,0
+
+	vxor	v4,v4,v12
+	VPMSUMD(v12,v20,const1)
+	ori	r2,r2,0
+
+	vxor	v5,v5,v13
+	VPMSUMD(v13,v21,const1)
+	ori	r2,r2,0
+
+	vxor	v6,v6,v14
+	VPMSUMD(v14,v22,const1)
+	ori	r2,r2,0
+
+	vxor	v7,v7,v15
+	VPMSUMD(v15,v23,const1)
+	ori	r2,r2,0
+
+.Lsecond_cool_down:
+	/* Second cool down pass */
+	vxor	v0,v0,v8
+	vxor	v1,v1,v9
+	vxor	v2,v2,v10
+	vxor	v3,v3,v11
+	vxor	v4,v4,v12
+	vxor	v5,v5,v13
+	vxor	v6,v6,v14
+	vxor	v7,v7,v15
+
+	/*
+	 * vpmsumd produces a 96 bit result in the least significant bits
+	 * of the register. Since we are bit reflected we have to shift it
+	 * left 32 bits so it occupies the least significant bits in the
+	 * bit reflected domain.
+	 */
+	vsldoi	v0,v0,zeroes,4
+	vsldoi	v1,v1,zeroes,4
+	vsldoi	v2,v2,zeroes,4
+	vsldoi	v3,v3,zeroes,4
+	vsldoi	v4,v4,zeroes,4
+	vsldoi	v5,v5,zeroes,4
+	vsldoi	v6,v6,zeroes,4
+	vsldoi	v7,v7,zeroes,4
+
+	/* xor with last 1024 bits */
+	lvx	v8,0,r4
+	lvx	v9,off16,r4
+	VPERM(v8,v8,v8,byteswap)
+	VPERM(v9,v9,v9,byteswap)
+	lvx	v10,off32,r4
+	lvx	v11,off48,r4
+	VPERM(v10,v10,v10,byteswap)
+	VPERM(v11,v11,v11,byteswap)
+	lvx	v12,off64,r4
+	lvx	v13,off80,r4
+	VPERM(v12,v12,v12,byteswap)
+	VPERM(v13,v13,v13,byteswap)
+	lvx	v14,off96,r4
+	lvx	v15,off112,r4
+	VPERM(v14,v14,v14,byteswap)
+	VPERM(v15,v15,v15,byteswap)
+
+	addi	r4,r4,8*16
+
+	vxor	v16,v0,v8
+	vxor	v17,v1,v9
+	vxor	v18,v2,v10
+	vxor	v19,v3,v11
+	vxor	v20,v4,v12
+	vxor	v21,v5,v13
+	vxor	v22,v6,v14
+	vxor	v23,v7,v15
+
+	li	r0,1
+	cmpdi	r6,0
+	addi	r6,r6,128
+	bne	1b
+
+	/* Work out how many bytes we have left */
+	andi.	r5,r5,127
+
+	/* Calculate where in the constant table we need to start */
+	subfic	r6,r5,128
+	add	r3,r3,r6
+
+	/* How many 16 byte chunks are in the tail */
+	srdi	r7,r5,4
+	mtctr	r7
+
+	/*
+	 * Reduce the previously calculated 1024 bits to 64 bits, shifting
+	 * 32 bits to include the trailing 32 bits of zeros
+	 */
+	lvx	v0,0,r3
+	lvx	v1,off16,r3
+	lvx	v2,off32,r3
+	lvx	v3,off48,r3
+	lvx	v4,off64,r3
+	lvx	v5,off80,r3
+	lvx	v6,off96,r3
+	lvx	v7,off112,r3
+	addi	r3,r3,8*16
+
+	VPMSUMW(v0,v16,v0)
+	VPMSUMW(v1,v17,v1)
+	VPMSUMW(v2,v18,v2)
+	VPMSUMW(v3,v19,v3)
+	VPMSUMW(v4,v20,v4)
+	VPMSUMW(v5,v21,v5)
+	VPMSUMW(v6,v22,v6)
+	VPMSUMW(v7,v23,v7)
+
+	/* Now reduce the tail (0 - 112 bytes) */
+	cmpdi	r7,0
+	beq	1f
+
+	lvx	v16,0,r4
+	lvx	v17,0,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off16,r4
+	lvx	v17,off16,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off32,r4
+	lvx	v17,off32,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off48,r4
+	lvx	v17,off48,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off64,r4
+	lvx	v17,off64,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off80,r4
+	lvx	v17,off80,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+	bdz	1f
+
+	lvx	v16,off96,r4
+	lvx	v17,off96,r3
+	VPERM(v16,v16,v16,byteswap)
+	VPMSUMW(v16,v16,v17)
+	vxor	v0,v0,v16
+
+	/* Now xor all the parallel chunks together */
+1:	vxor	v0,v0,v1
+	vxor	v2,v2,v3
+	vxor	v4,v4,v5
+	vxor	v6,v6,v7
+
+	vxor	v0,v0,v2
+	vxor	v4,v4,v6
+
+	vxor	v0,v0,v4
+
+.Lbarrett_reduction:
+	/* Barrett constants */
+	addis	r3,r2,.barrett_constants@toc@ha
+	addi	r3,r3,.barrett_constants@toc@l
+
+	lvx	const1,0,r3
+	lvx	const2,off16,r3
+
+	vsldoi	v1,v0,v0,8
+	vxor	v0,v0,v1		/* xor two 64 bit results together */
+
+	/* shift left one bit */
+	vspltisb v1,1
+	vsl	v0,v0,v1
+
+	vand	v0,v0,mask_64bit
+
+	/*
+	 * The reflected version of Barrett reduction. Instead of bit
+	 * reflecting our data (which is expensive to do), we bit reflect our
+	 * constants and our algorithm, which means the intermediate data in
+	 * our vector registers goes from 0-63 instead of 63-0. We can reflect
+	 * the algorithm because we don't carry in mod 2 arithmetic.
+	 */
+	vand	v1,v0,mask_32bit	/* bottom 32 bits of a */
+	VPMSUMD(v1,v1,const1)		/* ma */
+	vand	v1,v1,mask_32bit	/* bottom 32bits of ma */
+	VPMSUMD(v1,v1,const2)		/* qn */
+	vxor	v0,v0,v1		/* a - qn, subtraction is xor in GF(2) */
+
+	/*
+	 * Since we are bit reflected, the result (ie the low 32 bits) is in
+	 * the high 32 bits. We just need to shift it left 4 bytes
+	 * V0 [ 0 1 X 3 ]
+	 * V0 [ 0 X 2 3 ]
+	 */
+	vsldoi	v0,v0,zeroes,4		/* shift result into top 64 bits of */
+
+	/* Get it into r3 */
+	MFVRD(R3, v0)
+
+.Lout:
+	subi	r6,r1,56+10*16
+	subi	r7,r1,56+2*16
+
+	lvx	v20,0,r6
+	lvx	v21,off16,r6
+	lvx	v22,off32,r6
+	lvx	v23,off48,r6
+	lvx	v24,off64,r6
+	lvx	v25,off80,r6
+	lvx	v26,off96,r6
+	lvx	v27,off112,r6
+	lvx	v28,0,r7
+	lvx	v29,off16,r7
+
+	ld	r31,-8(r1)
+	ld	r30,-16(r1)
+	ld	r29,-24(r1)
+	ld	r28,-32(r1)
+	ld	r27,-40(r1)
+	ld	r26,-48(r1)
+	ld	r25,-56(r1)
+
+	blr
+
+.Lfirst_warm_up_done:
+	lvx	const1,0,r3
+	addi	r3,r3,16
+
+	VPMSUMD(v8,v16,const1)
+	VPMSUMD(v9,v17,const1)
+	VPMSUMD(v10,v18,const1)
+	VPMSUMD(v11,v19,const1)
+	VPMSUMD(v12,v20,const1)
+	VPMSUMD(v13,v21,const1)
+	VPMSUMD(v14,v22,const1)
+	VPMSUMD(v15,v23,const1)
+
+	b	.Lsecond_cool_down
+
+.Lshort:
+	cmpdi	r5,0
+	beq	.Lzero
+
+	addis	r3,r2,.short_constants@toc@ha
+	addi	r3,r3,.short_constants@toc@l
+
+	/* Calculate where in the constant table we need to start */
+	subfic	r6,r5,256
+	add	r3,r3,r6
+
+	/* How many 16 byte chunks? */
+	srdi	r7,r5,4
+	mtctr	r7
+
+	vxor	v19,v19,v19
+	vxor	v20,v20,v20
+
+	lvx	v0,0,r4
+	lvx	v16,0,r3
+	VPERM(v0,v0,v16,byteswap)
+	vxor	v0,v0,v8	/* xor in initial value */
+	VPMSUMW(v0,v0,v16)
+	bdz	.Lv0
+
+	lvx	v1,off16,r4
+	lvx	v17,off16,r3
+	VPERM(v1,v1,v17,byteswap)
+	VPMSUMW(v1,v1,v17)
+	bdz	.Lv1
+
+	lvx	v2,off32,r4
+	lvx	v16,off32,r3
+	VPERM(v2,v2,v16,byteswap)
+	VPMSUMW(v2,v2,v16)
+	bdz	.Lv2
+
+	lvx	v3,off48,r4
+	lvx	v17,off48,r3
+	VPERM(v3,v3,v17,byteswap)
+	VPMSUMW(v3,v3,v17)
+	bdz	.Lv3
+
+	lvx	v4,off64,r4
+	lvx	v16,off64,r3
+	VPERM(v4,v4,v16,byteswap)
+	VPMSUMW(v4,v4,v16)
+	bdz	.Lv4
+
+	lvx	v5,off80,r4
+	lvx	v17,off80,r3
+	VPERM(v5,v5,v17,byteswap)
+	VPMSUMW(v5,v5,v17)
+	bdz	.Lv5
+
+	lvx	v6,off96,r4
+	lvx	v16,off96,r3
+	VPERM(v6,v6,v16,byteswap)
+	VPMSUMW(v6,v6,v16)
+	bdz	.Lv6
+
+	lvx	v7,off112,r4
+	lvx	v17,off112,r3
+	VPERM(v7,v7,v17,byteswap)
+	VPMSUMW(v7,v7,v17)
+	bdz	.Lv7
+
+	addi	r3,r3,128
+	addi	r4,r4,128
+
+	lvx	v8,0,r4
+	lvx	v16,0,r3
+	VPERM(v8,v8,v16,byteswap)
+	VPMSUMW(v8,v8,v16)
+	bdz	.Lv8
+
+	lvx	v9,off16,r4
+	lvx	v17,off16,r3
+	VPERM(v9,v9,v17,byteswap)
+	VPMSUMW(v9,v9,v17)
+	bdz	.Lv9
+
+	lvx	v10,off32,r4
+	lvx	v16,off32,r3
+	VPERM(v10,v10,v16,byteswap)
+	VPMSUMW(v10,v10,v16)
+	bdz	.Lv10
+
+	lvx	v11,off48,r4
+	lvx	v17,off48,r3
+	VPERM(v11,v11,v17,byteswap)
+	VPMSUMW(v11,v11,v17)
+	bdz	.Lv11
+
+	lvx	v12,off64,r4
+	lvx	v16,off64,r3
+	VPERM(v12,v12,v16,byteswap)
+	VPMSUMW(v12,v12,v16)
+	bdz	.Lv12
+
+	lvx	v13,off80,r4
+	lvx	v17,off80,r3
+	VPERM(v13,v13,v17,byteswap)
+	VPMSUMW(v13,v13,v17)
+	bdz	.Lv13
+
+	lvx	v14,off96,r4
+	lvx	v16,off96,r3
+	VPERM(v14,v14,v16,byteswap)
+	VPMSUMW(v14,v14,v16)
+	bdz	.Lv14
+
+	lvx	v15,off112,r4
+	lvx	v17,off112,r3
+	VPERM(v15,v15,v17,byteswap)
+	VPMSUMW(v15,v15,v17)
+
+.Lv15:	vxor	v19,v19,v15
+.Lv14:	vxor	v20,v20,v14
+.Lv13:	vxor	v19,v19,v13
+.Lv12:	vxor	v20,v20,v12
+.Lv11:	vxor	v19,v19,v11
+.Lv10:	vxor	v20,v20,v10
+.Lv9:	vxor	v19,v19,v9
+.Lv8:	vxor	v20,v20,v8
+.Lv7:	vxor	v19,v19,v7
+.Lv6:	vxor	v20,v20,v6
+.Lv5:	vxor	v19,v19,v5
+.Lv4:	vxor	v20,v20,v4
+.Lv3:	vxor	v19,v19,v3
+.Lv2:	vxor	v20,v20,v2
+.Lv1:	vxor	v19,v19,v1
+.Lv0:	vxor	v20,v20,v0
+
+	vxor	v0,v19,v20
+
+	b	.Lbarrett_reduction
+
+.Lzero:
+	mr	r3,r10
+	b	.Lout
+
+FUNC_END(CRC_FUNCTION_NAME)
diff --git a/arch/powerpc/crypto/crc32c-vpmsum_asm.S b/arch/powerpc/crypto/crc32c-vpmsum_asm.S
index dc640b212299..c0d080caefc1 100644
--- a/arch/powerpc/crypto/crc32c-vpmsum_asm.S
+++ b/arch/powerpc/crypto/crc32c-vpmsum_asm.S
@@ -1,20 +1,5 @@ 
 /*
- * Calculate the checksum of data that is 16 byte aligned and a multiple of
- * 16 bytes.
- *
- * The first step is to reduce it to 1024 bits. We do this in 8 parallel
- * chunks in order to mask the latency of the vpmsum instructions. If we
- * have more than 32 kB of data to checksum we repeat this step multiple
- * times, passing in the previous 1024 bits.
- *
- * The next step is to reduce the 1024 bits to 64 bits. This step adds
- * 32 bits of 0s to the end - this matches what a CRC does. We just
- * calculate constants that land the data in this 32 bits.
- *
- * We then use fixed point Barrett reduction to compute a mod n over GF(2)
- * for n = CRC using POWER8 instructions. We use x = 32.
- *
- * http://en.wikipedia.org/wiki/Barrett_reduction
+ * Calculate a crc32c with vpmsum acceleration
  *
  * Copyright (C) 2015 Anton Blanchard <anton@au.ibm.com>, IBM
  *
@@ -23,9 +8,6 @@ 
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
-#include <asm/ppc_asm.h>
-#include <asm/ppc-opcode.h>
-
 	.section	.rodata
 .balign 16
 
@@ -33,7 +15,6 @@ 
 	/* byte reverse permute constant */
 	.octa 0x0F0E0D0C0B0A09080706050403020100
 
-#define MAX_SIZE	32768
 .constants:
 
 	/* Reduce 262144 kbits to 1024 bits */
@@ -860,694 +841,5 @@ 
 	/* 33 bit reflected Barrett constant n */
 	.octa 0x00000000000000000000000105ec76f1
 
-	.text
-
-#if defined(__BIG_ENDIAN__)
-#define BYTESWAP_DATA
-#else
-#undef BYTESWAP_DATA
-#endif
-
-#define off16		r25
-#define off32		r26
-#define off48		r27
-#define off64		r28
-#define off80		r29
-#define off96		r30
-#define off112		r31
-
-#define const1		v24
-#define const2		v25
-
-#define byteswap	v26
-#define	mask_32bit	v27
-#define	mask_64bit	v28
-#define zeroes		v29
-
-#ifdef BYTESWAP_DATA
-#define VPERM(A, B, C, D) vperm	A, B, C, D
-#else
-#define VPERM(A, B, C, D)
-#endif
-
-/* unsigned int __crc32c_vpmsum(unsigned int crc, void *p, unsigned long len) */
-FUNC_START(__crc32c_vpmsum)
-	std	r31,-8(r1)
-	std	r30,-16(r1)
-	std	r29,-24(r1)
-	std	r28,-32(r1)
-	std	r27,-40(r1)
-	std	r26,-48(r1)
-	std	r25,-56(r1)
-
-	li	off16,16
-	li	off32,32
-	li	off48,48
-	li	off64,64
-	li	off80,80
-	li	off96,96
-	li	off112,112
-	li	r0,0
-
-	/* Enough room for saving 10 non volatile VMX registers */
-	subi	r6,r1,56+10*16
-	subi	r7,r1,56+2*16
-
-	stvx	v20,0,r6
-	stvx	v21,off16,r6
-	stvx	v22,off32,r6
-	stvx	v23,off48,r6
-	stvx	v24,off64,r6
-	stvx	v25,off80,r6
-	stvx	v26,off96,r6
-	stvx	v27,off112,r6
-	stvx	v28,0,r7
-	stvx	v29,off16,r7
-
-	mr	r10,r3
-
-	vxor	zeroes,zeroes,zeroes
-	vspltisw v0,-1
-
-	vsldoi	mask_32bit,zeroes,v0,4
-	vsldoi	mask_64bit,zeroes,v0,8
-
-	/* Get the initial value into v8 */
-	vxor	v8,v8,v8
-	MTVRD(v8, R3)
-	vsldoi	v8,zeroes,v8,8	/* shift into bottom 32 bits */
-
-#ifdef BYTESWAP_DATA
-	addis	r3,r2,.byteswap_constant@toc@ha
-	addi	r3,r3,.byteswap_constant@toc@l
-
-	lvx	byteswap,0,r3
-	addi	r3,r3,16
-#endif
-
-	cmpdi	r5,256
-	blt	.Lshort
-
-	rldicr	r6,r5,0,56
-
-	/* Checksum in blocks of MAX_SIZE */
-1:	lis	r7,MAX_SIZE@h
-	ori	r7,r7,MAX_SIZE@l
-	mr	r9,r7
-	cmpd	r6,r7
-	bgt	2f
-	mr	r7,r6
-2:	subf	r6,r7,r6
-
-	/* our main loop does 128 bytes at a time */
-	srdi	r7,r7,7
-
-	/*
-	 * Work out the offset into the constants table to start at. Each
-	 * constant is 16 bytes, and it is used against 128 bytes of input
-	 * data - 128 / 16 = 8
-	 */
-	sldi	r8,r7,4
-	srdi	r9,r9,3
-	subf	r8,r8,r9
-
-	/* We reduce our final 128 bytes in a separate step */
-	addi	r7,r7,-1
-	mtctr	r7
-
-	addis	r3,r2,.constants@toc@ha
-	addi	r3,r3,.constants@toc@l
-
-	/* Find the start of our constants */
-	add	r3,r3,r8
-
-	/* zero v0-v7 which will contain our checksums */
-	vxor	v0,v0,v0
-	vxor	v1,v1,v1
-	vxor	v2,v2,v2
-	vxor	v3,v3,v3
-	vxor	v4,v4,v4
-	vxor	v5,v5,v5
-	vxor	v6,v6,v6
-	vxor	v7,v7,v7
-
-	lvx	const1,0,r3
-
-	/*
-	 * If we are looping back to consume more data we use the values
-	 * already in v16-v23.
-	 */
-	cmpdi	r0,1
-	beq	2f
-
-	/* First warm up pass */
-	lvx	v16,0,r4
-	lvx	v17,off16,r4
-	VPERM(v16,v16,v16,byteswap)
-	VPERM(v17,v17,v17,byteswap)
-	lvx	v18,off32,r4
-	lvx	v19,off48,r4
-	VPERM(v18,v18,v18,byteswap)
-	VPERM(v19,v19,v19,byteswap)
-	lvx	v20,off64,r4
-	lvx	v21,off80,r4
-	VPERM(v20,v20,v20,byteswap)
-	VPERM(v21,v21,v21,byteswap)
-	lvx	v22,off96,r4
-	lvx	v23,off112,r4
-	VPERM(v22,v22,v22,byteswap)
-	VPERM(v23,v23,v23,byteswap)
-	addi	r4,r4,8*16
-
-	/* xor in initial value */
-	vxor	v16,v16,v8
-
-2:	bdz	.Lfirst_warm_up_done
-
-	addi	r3,r3,16
-	lvx	const2,0,r3
-
-	/* Second warm up pass */
-	VPMSUMD(v8,v16,const1)
-	lvx	v16,0,r4
-	VPERM(v16,v16,v16,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v9,v17,const1)
-	lvx	v17,off16,r4
-	VPERM(v17,v17,v17,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v10,v18,const1)
-	lvx	v18,off32,r4
-	VPERM(v18,v18,v18,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v11,v19,const1)
-	lvx	v19,off48,r4
-	VPERM(v19,v19,v19,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v12,v20,const1)
-	lvx	v20,off64,r4
-	VPERM(v20,v20,v20,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v13,v21,const1)
-	lvx	v21,off80,r4
-	VPERM(v21,v21,v21,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v14,v22,const1)
-	lvx	v22,off96,r4
-	VPERM(v22,v22,v22,byteswap)
-	ori	r2,r2,0
-
-	VPMSUMD(v15,v23,const1)
-	lvx	v23,off112,r4
-	VPERM(v23,v23,v23,byteswap)
-
-	addi	r4,r4,8*16
-
-	bdz	.Lfirst_cool_down
-
-	/*
-	 * main loop. We modulo schedule it such that it takes three iterations
-	 * to complete - first iteration load, second iteration vpmsum, third
-	 * iteration xor.
-	 */
-	.balign	16
-4:	lvx	const1,0,r3
-	addi	r3,r3,16
-	ori	r2,r2,0
-
-	vxor	v0,v0,v8
-	VPMSUMD(v8,v16,const2)
-	lvx	v16,0,r4
-	VPERM(v16,v16,v16,byteswap)
-	ori	r2,r2,0
-
-	vxor	v1,v1,v9
-	VPMSUMD(v9,v17,const2)
-	lvx	v17,off16,r4
-	VPERM(v17,v17,v17,byteswap)
-	ori	r2,r2,0
-
-	vxor	v2,v2,v10
-	VPMSUMD(v10,v18,const2)
-	lvx	v18,off32,r4
-	VPERM(v18,v18,v18,byteswap)
-	ori	r2,r2,0
-
-	vxor	v3,v3,v11
-	VPMSUMD(v11,v19,const2)
-	lvx	v19,off48,r4
-	VPERM(v19,v19,v19,byteswap)
-	lvx	const2,0,r3
-	ori	r2,r2,0
-
-	vxor	v4,v4,v12
-	VPMSUMD(v12,v20,const1)
-	lvx	v20,off64,r4
-	VPERM(v20,v20,v20,byteswap)
-	ori	r2,r2,0
-
-	vxor	v5,v5,v13
-	VPMSUMD(v13,v21,const1)
-	lvx	v21,off80,r4
-	VPERM(v21,v21,v21,byteswap)
-	ori	r2,r2,0
-
-	vxor	v6,v6,v14
-	VPMSUMD(v14,v22,const1)
-	lvx	v22,off96,r4
-	VPERM(v22,v22,v22,byteswap)
-	ori	r2,r2,0
-
-	vxor	v7,v7,v15
-	VPMSUMD(v15,v23,const1)
-	lvx	v23,off112,r4
-	VPERM(v23,v23,v23,byteswap)
-
-	addi	r4,r4,8*16
-
-	bdnz	4b
-
-.Lfirst_cool_down:
-	/* First cool down pass */
-	lvx	const1,0,r3
-	addi	r3,r3,16
-
-	vxor	v0,v0,v8
-	VPMSUMD(v8,v16,const1)
-	ori	r2,r2,0
-
-	vxor	v1,v1,v9
-	VPMSUMD(v9,v17,const1)
-	ori	r2,r2,0
-
-	vxor	v2,v2,v10
-	VPMSUMD(v10,v18,const1)
-	ori	r2,r2,0
-
-	vxor	v3,v3,v11
-	VPMSUMD(v11,v19,const1)
-	ori	r2,r2,0
-
-	vxor	v4,v4,v12
-	VPMSUMD(v12,v20,const1)
-	ori	r2,r2,0
-
-	vxor	v5,v5,v13
-	VPMSUMD(v13,v21,const1)
-	ori	r2,r2,0
-
-	vxor	v6,v6,v14
-	VPMSUMD(v14,v22,const1)
-	ori	r2,r2,0
-
-	vxor	v7,v7,v15
-	VPMSUMD(v15,v23,const1)
-	ori	r2,r2,0
-
-.Lsecond_cool_down:
-	/* Second cool down pass */
-	vxor	v0,v0,v8
-	vxor	v1,v1,v9
-	vxor	v2,v2,v10
-	vxor	v3,v3,v11
-	vxor	v4,v4,v12
-	vxor	v5,v5,v13
-	vxor	v6,v6,v14
-	vxor	v7,v7,v15
-
-	/*
-	 * vpmsumd produces a 96 bit result in the least significant bits
-	 * of the register. Since we are bit reflected we have to shift it
-	 * left 32 bits so it occupies the least significant bits in the
-	 * bit reflected domain.
-	 */
-	vsldoi	v0,v0,zeroes,4
-	vsldoi	v1,v1,zeroes,4
-	vsldoi	v2,v2,zeroes,4
-	vsldoi	v3,v3,zeroes,4
-	vsldoi	v4,v4,zeroes,4
-	vsldoi	v5,v5,zeroes,4
-	vsldoi	v6,v6,zeroes,4
-	vsldoi	v7,v7,zeroes,4
-
-	/* xor with last 1024 bits */
-	lvx	v8,0,r4
-	lvx	v9,off16,r4
-	VPERM(v8,v8,v8,byteswap)
-	VPERM(v9,v9,v9,byteswap)
-	lvx	v10,off32,r4
-	lvx	v11,off48,r4
-	VPERM(v10,v10,v10,byteswap)
-	VPERM(v11,v11,v11,byteswap)
-	lvx	v12,off64,r4
-	lvx	v13,off80,r4
-	VPERM(v12,v12,v12,byteswap)
-	VPERM(v13,v13,v13,byteswap)
-	lvx	v14,off96,r4
-	lvx	v15,off112,r4
-	VPERM(v14,v14,v14,byteswap)
-	VPERM(v15,v15,v15,byteswap)
-
-	addi	r4,r4,8*16
-
-	vxor	v16,v0,v8
-	vxor	v17,v1,v9
-	vxor	v18,v2,v10
-	vxor	v19,v3,v11
-	vxor	v20,v4,v12
-	vxor	v21,v5,v13
-	vxor	v22,v6,v14
-	vxor	v23,v7,v15
-
-	li	r0,1
-	cmpdi	r6,0
-	addi	r6,r6,128
-	bne	1b
-
-	/* Work out how many bytes we have left */
-	andi.	r5,r5,127
-
-	/* Calculate where in the constant table we need to start */
-	subfic	r6,r5,128
-	add	r3,r3,r6
-
-	/* How many 16 byte chunks are in the tail */
-	srdi	r7,r5,4
-	mtctr	r7
-
-	/*
-	 * Reduce the previously calculated 1024 bits to 64 bits, shifting
-	 * 32 bits to include the trailing 32 bits of zeros
-	 */
-	lvx	v0,0,r3
-	lvx	v1,off16,r3
-	lvx	v2,off32,r3
-	lvx	v3,off48,r3
-	lvx	v4,off64,r3
-	lvx	v5,off80,r3
-	lvx	v6,off96,r3
-	lvx	v7,off112,r3
-	addi	r3,r3,8*16
-
-	VPMSUMW(v0,v16,v0)
-	VPMSUMW(v1,v17,v1)
-	VPMSUMW(v2,v18,v2)
-	VPMSUMW(v3,v19,v3)
-	VPMSUMW(v4,v20,v4)
-	VPMSUMW(v5,v21,v5)
-	VPMSUMW(v6,v22,v6)
-	VPMSUMW(v7,v23,v7)
-
-	/* Now reduce the tail (0 - 112 bytes) */
-	cmpdi	r7,0
-	beq	1f
-
-	lvx	v16,0,r4
-	lvx	v17,0,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off16,r4
-	lvx	v17,off16,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off32,r4
-	lvx	v17,off32,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off48,r4
-	lvx	v17,off48,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off64,r4
-	lvx	v17,off64,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off80,r4
-	lvx	v17,off80,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-	bdz	1f
-
-	lvx	v16,off96,r4
-	lvx	v17,off96,r3
-	VPERM(v16,v16,v16,byteswap)
-	VPMSUMW(v16,v16,v17)
-	vxor	v0,v0,v16
-
-	/* Now xor all the parallel chunks together */
-1:	vxor	v0,v0,v1
-	vxor	v2,v2,v3
-	vxor	v4,v4,v5
-	vxor	v6,v6,v7
-
-	vxor	v0,v0,v2
-	vxor	v4,v4,v6
-
-	vxor	v0,v0,v4
-
-.Lbarrett_reduction:
-	/* Barrett constants */
-	addis	r3,r2,.barrett_constants@toc@ha
-	addi	r3,r3,.barrett_constants@toc@l
-
-	lvx	const1,0,r3
-	lvx	const2,off16,r3
-
-	vsldoi	v1,v0,v0,8
-	vxor	v0,v0,v1		/* xor two 64 bit results together */
-
-	/* shift left one bit */
-	vspltisb v1,1
-	vsl	v0,v0,v1
-
-	vand	v0,v0,mask_64bit
-
-	/*
-	 * The reflected version of Barrett reduction. Instead of bit
-	 * reflecting our data (which is expensive to do), we bit reflect our
-	 * constants and our algorithm, which means the intermediate data in
-	 * our vector registers goes from 0-63 instead of 63-0. We can reflect
-	 * the algorithm because we don't carry in mod 2 arithmetic.
-	 */
-	vand	v1,v0,mask_32bit	/* bottom 32 bits of a */
-	VPMSUMD(v1,v1,const1)		/* ma */
-	vand	v1,v1,mask_32bit	/* bottom 32bits of ma */
-	VPMSUMD(v1,v1,const2)		/* qn */
-	vxor	v0,v0,v1		/* a - qn, subtraction is xor in GF(2) */
-
-	/*
-	 * Since we are bit reflected, the result (ie the low 32 bits) is in
-	 * the high 32 bits. We just need to shift it left 4 bytes
-	 * V0 [ 0 1 X 3 ]
-	 * V0 [ 0 X 2 3 ]
-	 */
-	vsldoi	v0,v0,zeroes,4		/* shift result into top 64 bits of */
-
-	/* Get it into r3 */
-	MFVRD(R3, v0)
-
-.Lout:
-	subi	r6,r1,56+10*16
-	subi	r7,r1,56+2*16
-
-	lvx	v20,0,r6
-	lvx	v21,off16,r6
-	lvx	v22,off32,r6
-	lvx	v23,off48,r6
-	lvx	v24,off64,r6
-	lvx	v25,off80,r6
-	lvx	v26,off96,r6
-	lvx	v27,off112,r6
-	lvx	v28,0,r7
-	lvx	v29,off16,r7
-
-	ld	r31,-8(r1)
-	ld	r30,-16(r1)
-	ld	r29,-24(r1)
-	ld	r28,-32(r1)
-	ld	r27,-40(r1)
-	ld	r26,-48(r1)
-	ld	r25,-56(r1)
-
-	blr
-
-.Lfirst_warm_up_done:
-	lvx	const1,0,r3
-	addi	r3,r3,16
-
-	VPMSUMD(v8,v16,const1)
-	VPMSUMD(v9,v17,const1)
-	VPMSUMD(v10,v18,const1)
-	VPMSUMD(v11,v19,const1)
-	VPMSUMD(v12,v20,const1)
-	VPMSUMD(v13,v21,const1)
-	VPMSUMD(v14,v22,const1)
-	VPMSUMD(v15,v23,const1)
-
-	b	.Lsecond_cool_down
-
-.Lshort:
-	cmpdi	r5,0
-	beq	.Lzero
-
-	addis	r3,r2,.short_constants@toc@ha
-	addi	r3,r3,.short_constants@toc@l
-
-	/* Calculate where in the constant table we need to start */
-	subfic	r6,r5,256
-	add	r3,r3,r6
-
-	/* How many 16 byte chunks? */
-	srdi	r7,r5,4
-	mtctr	r7
-
-	vxor	v19,v19,v19
-	vxor	v20,v20,v20
-
-	lvx	v0,0,r4
-	lvx	v16,0,r3
-	VPERM(v0,v0,v16,byteswap)
-	vxor	v0,v0,v8	/* xor in initial value */
-	VPMSUMW(v0,v0,v16)
-	bdz	.Lv0
-
-	lvx	v1,off16,r4
-	lvx	v17,off16,r3
-	VPERM(v1,v1,v17,byteswap)
-	VPMSUMW(v1,v1,v17)
-	bdz	.Lv1
-
-	lvx	v2,off32,r4
-	lvx	v16,off32,r3
-	VPERM(v2,v2,v16,byteswap)
-	VPMSUMW(v2,v2,v16)
-	bdz	.Lv2
-
-	lvx	v3,off48,r4
-	lvx	v17,off48,r3
-	VPERM(v3,v3,v17,byteswap)
-	VPMSUMW(v3,v3,v17)
-	bdz	.Lv3
-
-	lvx	v4,off64,r4
-	lvx	v16,off64,r3
-	VPERM(v4,v4,v16,byteswap)
-	VPMSUMW(v4,v4,v16)
-	bdz	.Lv4
-
-	lvx	v5,off80,r4
-	lvx	v17,off80,r3
-	VPERM(v5,v5,v17,byteswap)
-	VPMSUMW(v5,v5,v17)
-	bdz	.Lv5
-
-	lvx	v6,off96,r4
-	lvx	v16,off96,r3
-	VPERM(v6,v6,v16,byteswap)
-	VPMSUMW(v6,v6,v16)
-	bdz	.Lv6
-
-	lvx	v7,off112,r4
-	lvx	v17,off112,r3
-	VPERM(v7,v7,v17,byteswap)
-	VPMSUMW(v7,v7,v17)
-	bdz	.Lv7
-
-	addi	r3,r3,128
-	addi	r4,r4,128
-
-	lvx	v8,0,r4
-	lvx	v16,0,r3
-	VPERM(v8,v8,v16,byteswap)
-	VPMSUMW(v8,v8,v16)
-	bdz	.Lv8
-
-	lvx	v9,off16,r4
-	lvx	v17,off16,r3
-	VPERM(v9,v9,v17,byteswap)
-	VPMSUMW(v9,v9,v17)
-	bdz	.Lv9
-
-	lvx	v10,off32,r4
-	lvx	v16,off32,r3
-	VPERM(v10,v10,v16,byteswap)
-	VPMSUMW(v10,v10,v16)
-	bdz	.Lv10
-
-	lvx	v11,off48,r4
-	lvx	v17,off48,r3
-	VPERM(v11,v11,v17,byteswap)
-	VPMSUMW(v11,v11,v17)
-	bdz	.Lv11
-
-	lvx	v12,off64,r4
-	lvx	v16,off64,r3
-	VPERM(v12,v12,v16,byteswap)
-	VPMSUMW(v12,v12,v16)
-	bdz	.Lv12
-
-	lvx	v13,off80,r4
-	lvx	v17,off80,r3
-	VPERM(v13,v13,v17,byteswap)
-	VPMSUMW(v13,v13,v17)
-	bdz	.Lv13
-
-	lvx	v14,off96,r4
-	lvx	v16,off96,r3
-	VPERM(v14,v14,v16,byteswap)
-	VPMSUMW(v14,v14,v16)
-	bdz	.Lv14
-
-	lvx	v15,off112,r4
-	lvx	v17,off112,r3
-	VPERM(v15,v15,v17,byteswap)
-	VPMSUMW(v15,v15,v17)
-
-.Lv15:	vxor	v19,v19,v15
-.Lv14:	vxor	v20,v20,v14
-.Lv13:	vxor	v19,v19,v13
-.Lv12:	vxor	v20,v20,v12
-.Lv11:	vxor	v19,v19,v11
-.Lv10:	vxor	v20,v20,v10
-.Lv9:	vxor	v19,v19,v9
-.Lv8:	vxor	v20,v20,v8
-.Lv7:	vxor	v19,v19,v7
-.Lv6:	vxor	v20,v20,v6
-.Lv5:	vxor	v19,v19,v5
-.Lv4:	vxor	v20,v20,v4
-.Lv3:	vxor	v19,v19,v3
-.Lv2:	vxor	v20,v20,v2
-.Lv1:	vxor	v19,v19,v1
-.Lv0:	vxor	v20,v20,v0
-
-	vxor	v0,v19,v20
-
-	b	.Lbarrett_reduction
-
-.Lzero:
-	mr	r3,r10
-	b	.Lout
-
-FUNC_END(__crc32_vpmsum)
+#define CRC_FUNCTION_NAME __crc32c_vpmsum
+#include "crc32-vpmsum_core.S"