Merging upstream version 6.9.7.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 240 insertions, 0 deletions

diff --git a/arch/s390/crypto/crc32le-vx.c b/arch/s390/crypto/crc32le-vx.c
new file mode 100644
index 0000000000..2f629f394d
--- /dev/null
+++ b/arch/s390/crypto/crc32le-vx.c
@@ -0,0 +1,240 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Hardware-accelerated CRC-32 variants for Linux on z Systems
+ *
+ * Use the z/Architecture Vector Extension Facility to accelerate the
+ * computing of bitreflected CRC-32 checksums for IEEE 802.3 Ethernet
+ * and Castagnoli.
+ *
+ * This CRC-32 implementation algorithm is bitreflected and processes
+ * the least-significant bit first (Little-Endian).
+ *
+ * Copyright IBM Corp. 2015
+ * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <asm/fpu.h>
+#include "crc32-vx.h"
+
+/* Vector register range containing CRC-32 constants */
+#define CONST_PERM_LE2BE	9
+#define CONST_R2R1		10
+#define CONST_R4R3		11
+#define CONST_R5		12
+#define CONST_RU_POLY		13
+#define CONST_CRC_POLY		14
+
+/*
+ * The CRC-32 constant block contains reduction constants to fold and
+ * process particular chunks of the input data stream in parallel.
+ *
+ * For the CRC-32 variants, the constants are precomputed according to
+ * these definitions:
+ *
+ *	R1 = [(x4*128+32 mod P'(x) << 32)]' << 1
+ *	R2 = [(x4*128-32 mod P'(x) << 32)]' << 1
+ *	R3 = [(x128+32 mod P'(x) << 32)]'   << 1
+ *	R4 = [(x128-32 mod P'(x) << 32)]'   << 1
+ *	R5 = [(x64 mod P'(x) << 32)]'	    << 1
+ *	R6 = [(x32 mod P'(x) << 32)]'	    << 1
+ *
+ *	The bitreflected Barret reduction constant, u', is defined as
+ *	the bit reversal of floor(x**64 / P(x)).
+ *
+ *	where P(x) is the polynomial in the normal domain and the P'(x) is the
+ *	polynomial in the reversed (bitreflected) domain.
+ *
+ * CRC-32 (IEEE 802.3 Ethernet, ...) polynomials:
+ *
+ *	P(x)  = 0x04C11DB7
+ *	P'(x) = 0xEDB88320
+ *
+ * CRC-32C (Castagnoli) polynomials:
+ *
+ *	P(x)  = 0x1EDC6F41
+ *	P'(x) = 0x82F63B78
+ */
+
+static unsigned long constants_CRC_32_LE[] = {
+	0x0f0e0d0c0b0a0908, 0x0706050403020100,	/* BE->LE mask */
+	0x1c6e41596, 0x154442bd4,		/* R2, R1 */
+	0x0ccaa009e, 0x1751997d0,		/* R4, R3 */
+	0x0, 0x163cd6124,			/* R5 */
+	0x0, 0x1f7011641,			/* u' */
+	0x0, 0x1db710641			/* P'(x) << 1 */
+};
+
+static unsigned long constants_CRC_32C_LE[] = {
+	0x0f0e0d0c0b0a0908, 0x0706050403020100,	/* BE->LE mask */
+	0x09e4addf8, 0x740eef02,		/* R2, R1 */
+	0x14cd00bd6, 0xf20c0dfe,		/* R4, R3 */
+	0x0, 0x0dd45aab8,			/* R5 */
+	0x0, 0x0dea713f1,			/* u' */
+	0x0, 0x105ec76f0			/* P'(x) << 1 */
+};
+
+/**
+ * crc32_le_vgfm_generic - Compute CRC-32 (LE variant) with vector registers
+ * @crc: Initial CRC value, typically ~0.
+ * @buf: Input buffer pointer, performance might be improved if the
+ *	 buffer is on a doubleword boundary.
+ * @size: Size of the buffer, must be 64 bytes or greater.
+ * @constants: CRC-32 constant pool base pointer.
+ *
+ * Register usage:
+ *	V0:	  Initial CRC value and intermediate constants and results.
+ *	V1..V4:	  Data for CRC computation.
+ *	V5..V8:	  Next data chunks that are fetched from the input buffer.
+ *	V9:	  Constant for BE->LE conversion and shift operations
+ *	V10..V14: CRC-32 constants.
+ */
+static u32 crc32_le_vgfm_generic(u32 crc, unsigned char const *buf, size_t size, unsigned long *constants)
+{
+	/* Load CRC-32 constants */
+	fpu_vlm(CONST_PERM_LE2BE, CONST_CRC_POLY, constants);
+
+	/*
+	 * Load the initial CRC value.
+	 *
+	 * The CRC value is loaded into the rightmost word of the
+	 * vector register and is later XORed with the LSB portion
+	 * of the loaded input data.
+	 */
+	fpu_vzero(0);			/* Clear V0 */
+	fpu_vlvgf(0, crc, 3);		/* Load CRC into rightmost word */
+
+	/* Load a 64-byte data chunk and XOR with CRC */
+	fpu_vlm(1, 4, buf);
+	fpu_vperm(1, 1, 1, CONST_PERM_LE2BE);
+	fpu_vperm(2, 2, 2, CONST_PERM_LE2BE);
+	fpu_vperm(3, 3, 3, CONST_PERM_LE2BE);
+	fpu_vperm(4, 4, 4, CONST_PERM_LE2BE);
+
+	fpu_vx(1, 0, 1);		/* V1 ^= CRC */
+	buf += 64;
+	size -= 64;
+
+	while (size >= 64) {
+		fpu_vlm(5, 8, buf);
+		fpu_vperm(5, 5, 5, CONST_PERM_LE2BE);
+		fpu_vperm(6, 6, 6, CONST_PERM_LE2BE);
+		fpu_vperm(7, 7, 7, CONST_PERM_LE2BE);
+		fpu_vperm(8, 8, 8, CONST_PERM_LE2BE);
+		/*
+		 * Perform a GF(2) multiplication of the doublewords in V1 with
+		 * the R1 and R2 reduction constants in V0.  The intermediate
+		 * result is then folded (accumulated) with the next data chunk
+		 * in V5 and stored in V1. Repeat this step for the register
+		 * contents in V2, V3, and V4 respectively.
+		 */
+		fpu_vgfmag(1, CONST_R2R1, 1, 5);
+		fpu_vgfmag(2, CONST_R2R1, 2, 6);
+		fpu_vgfmag(3, CONST_R2R1, 3, 7);
+		fpu_vgfmag(4, CONST_R2R1, 4, 8);
+		buf += 64;
+		size -= 64;
+	}
+
+	/*
+	 * Fold V1 to V4 into a single 128-bit value in V1.  Multiply V1 with R3
+	 * and R4 and accumulating the next 128-bit chunk until a single 128-bit
+	 * value remains.
+	 */
+	fpu_vgfmag(1, CONST_R4R3, 1, 2);
+	fpu_vgfmag(1, CONST_R4R3, 1, 3);
+	fpu_vgfmag(1, CONST_R4R3, 1, 4);
+
+	while (size >= 16) {
+		fpu_vl(2, buf);
+		fpu_vperm(2, 2, 2, CONST_PERM_LE2BE);
+		fpu_vgfmag(1, CONST_R4R3, 1, 2);
+		buf += 16;
+		size -= 16;
+	}
+
+	/*
+	 * Set up a vector register for byte shifts.  The shift value must
+	 * be loaded in bits 1-4 in byte element 7 of a vector register.
+	 * Shift by 8 bytes: 0x40
+	 * Shift by 4 bytes: 0x20
+	 */
+	fpu_vleib(9, 0x40, 7);
+
+	/*
+	 * Prepare V0 for the next GF(2) multiplication: shift V0 by 8 bytes
+	 * to move R4 into the rightmost doubleword and set the leftmost
+	 * doubleword to 0x1.
+	 */
+	fpu_vsrlb(0, CONST_R4R3, 9);
+	fpu_vleig(0, 1, 0);
+
+	/*
+	 * Compute GF(2) product of V1 and V0.	The rightmost doubleword
+	 * of V1 is multiplied with R4.  The leftmost doubleword of V1 is
+	 * multiplied by 0x1 and is then XORed with rightmost product.
+	 * Implicitly, the intermediate leftmost product becomes padded
+	 */
+	fpu_vgfmg(1, 0, 1);
+
+	/*
+	 * Now do the final 32-bit fold by multiplying the rightmost word
+	 * in V1 with R5 and XOR the result with the remaining bits in V1.
+	 *
+	 * To achieve this by a single VGFMAG, right shift V1 by a word
+	 * and store the result in V2 which is then accumulated.  Use the
+	 * vector unpack instruction to load the rightmost half of the
+	 * doubleword into the rightmost doubleword element of V1; the other
+	 * half is loaded in the leftmost doubleword.
+	 * The vector register with CONST_R5 contains the R5 constant in the
+	 * rightmost doubleword and the leftmost doubleword is zero to ignore
+	 * the leftmost product of V1.
+	 */
+	fpu_vleib(9, 0x20, 7);		  /* Shift by words */
+	fpu_vsrlb(2, 1, 9);		  /* Store remaining bits in V2 */
+	fpu_vupllf(1, 1);		  /* Split rightmost doubleword */
+	fpu_vgfmag(1, CONST_R5, 1, 2);	  /* V1 = (V1 * R5) XOR V2 */
+
+	/*
+	 * Apply a Barret reduction to compute the final 32-bit CRC value.
+	 *
+	 * The input values to the Barret reduction are the degree-63 polynomial
+	 * in V1 (R(x)), degree-32 generator polynomial, and the reduction
+	 * constant u.	The Barret reduction result is the CRC value of R(x) mod
+	 * P(x).
+	 *
+	 * The Barret reduction algorithm is defined as:
+	 *
+	 *    1. T1(x) = floor( R(x) / x^32 ) GF2MUL u
+	 *    2. T2(x) = floor( T1(x) / x^32 ) GF2MUL P(x)
+	 *    3. C(x)  = R(x) XOR T2(x) mod x^32
+	 *
+	 *  Note: The leftmost doubleword of vector register containing
+	 *  CONST_RU_POLY is zero and, thus, the intermediate GF(2) product
+	 *  is zero and does not contribute to the final result.
+	 */
+
+	/* T1(x) = floor( R(x) / x^32 ) GF2MUL u */
+	fpu_vupllf(2, 1);
+	fpu_vgfmg(2, CONST_RU_POLY, 2);
+
+	/*
+	 * Compute the GF(2) product of the CRC polynomial with T1(x) in
+	 * V2 and XOR the intermediate result, T2(x), with the value in V1.
+	 * The final result is stored in word element 2 of V2.
+	 */
+	fpu_vupllf(2, 2);
+	fpu_vgfmag(2, CONST_CRC_POLY, 2, 1);
+
+	return fpu_vlgvf(2, 2);
+}
+
+u32 crc32_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size)
+{
+	return crc32_le_vgfm_generic(crc, buf, size, &constants_CRC_32_LE[0]);
+}
+
+u32 crc32c_le_vgfm_16(u32 crc, unsigned char const *buf, size_t size)
+{
+	return crc32_le_vgfm_generic(crc, buf, size, &constants_CRC_32C_LE[0]);
+}