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Revision b8dc6038ff894d0eb0b5d61c9fafdf323ec10251 authored by Jan Glauber on 14 January 2006, 21:20:53 UTC, committed by Linus Torvalds on 15 January 2006, 02:27:08 UTC 
[PATCH] s390: des crypto code speedup
 
Provide ECB and CBC encrypt / decrypt functions to crypto API to speed up our
hardware accelerated DES implementation.  This new functions allow the crypto
API to call ECB / CBC directly with large blocks in difference to the old
functions that were calles with algorithm block size (8 bytes for DES).

This is up to factor 10 faster than our old hardware implementation :)

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1 parent c135783
Raw File
gen_crc32table.c 
#include <stdio.h>
#include "crc32defs.h"
#include <inttypes.h>

#define ENTRIES_PER_LINE 4

#define LE_TABLE_SIZE (1 << CRC_LE_BITS)
#define BE_TABLE_SIZE (1 << CRC_BE_BITS)

static uint32_t crc32table_le[LE_TABLE_SIZE];
static uint32_t crc32table_be[BE_TABLE_SIZE];

/**
 * crc32init_le() - allocate and initialize LE table data
 *
 * crc is the crc of the byte i; other entries are filled in based on the
 * fact that crctable[i^j] = crctable[i] ^ crctable[j].
 *
 */
static void crc32init_le(void)
{
	unsigned i, j;
	uint32_t crc = 1;

	crc32table_le[0] = 0;

	for (i = 1 << (CRC_LE_BITS - 1); i; i >>= 1) {
		crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
		for (j = 0; j < LE_TABLE_SIZE; j += 2 * i)
			crc32table_le[i + j] = crc ^ crc32table_le[j];
	}
}

/**
 * crc32init_be() - allocate and initialize BE table data
 */
static void crc32init_be(void)
{
	unsigned i, j;
	uint32_t crc = 0x80000000;

	crc32table_be[0] = 0;

	for (i = 1; i < BE_TABLE_SIZE; i <<= 1) {
		crc = (crc << 1) ^ ((crc & 0x80000000) ? CRCPOLY_BE : 0);
		for (j = 0; j < i; j++)
			crc32table_be[i + j] = crc ^ crc32table_be[j];
	}
}

static void output_table(uint32_t table[], int len, char *trans)
{
	int i;

	for (i = 0; i < len - 1; i++) {
		if (i % ENTRIES_PER_LINE == 0)
			printf("\n");
		printf("%s(0x%8.8xL), ", trans, table[i]);
	}
	printf("%s(0x%8.8xL)\n", trans, table[len - 1]);
}

int main(int argc, char** argv)
{
	printf("/* this file is generated - do not edit */\n\n");

	if (CRC_LE_BITS > 1) {
		crc32init_le();
		printf("static const u32 crc32table_le[] = {");
		output_table(crc32table_le, LE_TABLE_SIZE, "tole");
		printf("};\n");
	}

	if (CRC_BE_BITS > 1) {
		crc32init_be();
		printf("static const u32 crc32table_be[] = {");
		output_table(crc32table_be, BE_TABLE_SIZE, "tobe");
		printf("};\n");
	}

	return 0;
}
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