linux-imx

/* -*- linux-c -*- ------------------------------------------------------- *

 *

 *   Copyright 2002 H. Peter Anvin - All Rights Reserved

 *

 *   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, Inc., 53 Temple Place Ste 330,

 *   Boston MA 02111-1307, USA; either version 2 of the License, or

 *   (at your option) any later version; incorporated herein by reference.

 *

 * ----------------------------------------------------------------------- */

​

/*

 * raid6/mmx.c

 *

 * MMX implementation of RAID-6 syndrome functions

 */

​

#ifdef CONFIG_X86_32

​

#include <linux/raid/pq.h>

#include "x86.h"

​

/* Shared with raid6/sse1.c */

const struct raid6_mmx_constants {

    u64 x1d;

} raid6_mmx_constants = {

    0x1d1d1d1d1d1d1d1dULL,

};

​

static int raid6_have_mmx(void)

{

    /* Not really "boot_cpu" but "all_cpus" */

    return boot_cpu_has(X86_FEATURE_MMX);

}

​

/*

 * Plain MMX implementation

 */

static void raid6_mmx1_gen_syndrome(int disks, size_t bytes, void **ptrs)

{

    u8 **dptr = (u8 **)ptrs;

    u8 *p, *q;

    int d, z, z0;

​

    z0 = disks - 3;     /* Highest data disk */

    p = dptr[z0+1];     /* XOR parity */

    q = dptr[z0+2];     /* RS syndrome */

​

    kernel_fpu_begin();

​

    asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));

    asm volatile("pxor %mm5,%mm5"); /* Zero temp */

​

    for ( d = 0 ; d < bytes ; d += 8 ) {

        asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */

        asm volatile("movq %mm2,%mm4"); /* Q[0] */

        for ( z = z0-1 ; z >= 0 ; z-- ) {

            asm volatile("movq %0,%%mm6" : : "m" (dptr[z][d]));

            asm volatile("pcmpgtb %mm4,%mm5");

            asm volatile("paddb %mm4,%mm4");

            asm volatile("pand %mm0,%mm5");

            asm volatile("pxor %mm5,%mm4");