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Diffstat (limited to 'arch/s390/crypto/crc32le-vx.S')
| -rw-r--r-- | arch/s390/crypto/crc32le-vx.S | 273 |
1 files changed, 0 insertions, 273 deletions
diff --git a/arch/s390/crypto/crc32le-vx.S b/arch/s390/crypto/crc32le-vx.S deleted file mode 100644 index 71caf0f4ec08..000000000000 --- a/arch/s390/crypto/crc32le-vx.S +++ /dev/null @@ -1,273 +0,0 @@ -/* 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/linkage.h> -#include <asm/nospec-insn.h> -#include <asm/vx-insn.h> - -/* Vector register range containing CRC-32 constants */ -#define CONST_PERM_LE2BE %v9 -#define CONST_R2R1 %v10 -#define CONST_R4R3 %v11 -#define CONST_R5 %v12 -#define CONST_RU_POLY %v13 -#define CONST_CRC_POLY %v14 - -.data -.align 8 - -/* - * 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 - */ - -.Lconstants_CRC_32_LE: - .octa 0x0F0E0D0C0B0A09080706050403020100 # BE->LE mask - .quad 0x1c6e41596, 0x154442bd4 # R2, R1 - .quad 0x0ccaa009e, 0x1751997d0 # R4, R3 - .octa 0x163cd6124 # R5 - .octa 0x1F7011641 # u' - .octa 0x1DB710641 # P'(x) << 1 - -.Lconstants_CRC_32C_LE: - .octa 0x0F0E0D0C0B0A09080706050403020100 # BE->LE mask - .quad 0x09e4addf8, 0x740eef02 # R2, R1 - .quad 0x14cd00bd6, 0xf20c0dfe # R4, R3 - .octa 0x0dd45aab8 # R5 - .octa 0x0dea713f1 # u' - .octa 0x105ec76f0 # P'(x) << 1 - -.previous - - GEN_BR_THUNK %r14 - -.text - -/* - * The CRC-32 functions use these calling conventions: - * - * Parameters: - * - * %r2: Initial CRC value, typically ~0; and final CRC (return) value. - * %r3: Input buffer pointer, performance might be improved if the - * buffer is on a doubleword boundary. - * %r4: Length of the buffer, must be 64 bytes or greater. - * - * Register usage: - * - * %r5: CRC-32 constant pool base pointer. - * 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. - */ - -ENTRY(crc32_le_vgfm_16) - larl %r5,.Lconstants_CRC_32_LE - j crc32_le_vgfm_generic -ENDPROC(crc32_le_vgfm_16) - -ENTRY(crc32c_le_vgfm_16) - larl %r5,.Lconstants_CRC_32C_LE - j crc32_le_vgfm_generic -ENDPROC(crc32c_le_vgfm_16) - -ENTRY(crc32_le_vgfm_generic) - /* Load CRC-32 constants */ - VLM CONST_PERM_LE2BE,CONST_CRC_POLY,0,%r5 - - /* - * 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. - */ - VZERO %v0 /* Clear V0 */ - VLVGF %v0,%r2,3 /* Load CRC into rightmost word */ - - /* Load a 64-byte data chunk and XOR with CRC */ - VLM %v1,%v4,0,%r3 /* 64-bytes into V1..V4 */ - VPERM %v1,%v1,%v1,CONST_PERM_LE2BE - VPERM %v2,%v2,%v2,CONST_PERM_LE2BE - VPERM %v3,%v3,%v3,CONST_PERM_LE2BE - VPERM %v4,%v4,%v4,CONST_PERM_LE2BE - - VX %v1,%v0,%v1 /* V1 ^= CRC */ - aghi %r3,64 /* BUF = BUF + 64 */ - aghi %r4,-64 /* LEN = LEN - 64 */ - - cghi %r4,64 - jl .Lless_than_64bytes - -.Lfold_64bytes_loop: - /* Load the next 64-byte data chunk into V5 to V8 */ - VLM %v5,%v8,0,%r3 - VPERM %v5,%v5,%v5,CONST_PERM_LE2BE - VPERM %v6,%v6,%v6,CONST_PERM_LE2BE - VPERM %v7,%v7,%v7,CONST_PERM_LE2BE - VPERM %v8,%v8,%v8,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. - */ - VGFMAG %v1,CONST_R2R1,%v1,%v5 - VGFMAG %v2,CONST_R2R1,%v2,%v6 - VGFMAG %v3,CONST_R2R1,%v3,%v7 - VGFMAG %v4,CONST_R2R1,%v4,%v8 - - aghi %r3,64 /* BUF = BUF + 64 */ - aghi %r4,-64 /* LEN = LEN - 64 */ - - cghi %r4,64 - jnl .Lfold_64bytes_loop - -.Lless_than_64bytes: - /* - * 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. - */ - VGFMAG %v1,CONST_R4R3,%v1,%v2 - VGFMAG %v1,CONST_R4R3,%v1,%v3 - VGFMAG %v1,CONST_R4R3,%v1,%v4 - - cghi %r4,16 - jl .Lfinal_fold - -.Lfold_16bytes_loop: - - VL %v2,0,,%r3 /* Load next data chunk */ - VPERM %v2,%v2,%v2,CONST_PERM_LE2BE - VGFMAG %v1,CONST_R4R3,%v1,%v2 /* Fold next data chunk */ - - aghi %r3,16 - aghi %r4,-16 - - cghi %r4,16 - jnl .Lfold_16bytes_loop - -.Lfinal_fold: - /* - * 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 - */ - VLEIB %v9,0x40,7 - - /* - * 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. - */ - VSRLB %v0,CONST_R4R3,%v9 - VLEIG %v0,1,0 - - /* - * 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 - */ - VGFMG %v1,%v0,%v1 - - /* - * 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. - */ - VLEIB %v9,0x20,7 /* Shift by words */ - VSRLB %v2,%v1,%v9 /* Store remaining bits in V2 */ - VUPLLF %v1,%v1 /* Split rightmost doubleword */ - VGFMAG %v1,CONST_R5,%v1,%v2 /* 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 */ - VUPLLF %v2,%v1 - VGFMG %v2,CONST_RU_POLY,%v2 - - /* - * 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. - */ - VUPLLF %v2,%v2 - VGFMAG %v2,CONST_CRC_POLY,%v2,%v1 - -.Ldone: - VLGVF %r2,%v2,2 - BR_EX %r14 -ENDPROC(crc32_le_vgfm_generic) - -.previous |