/* -*- 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,
* Bostom MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* raid6sse1.c
*
* SSE-1/MMXEXT implementation of RAID-6 syndrome functions
*
* This is really an MMX implementation, but it requires SSE-1 or
* AMD MMXEXT for prefetch support and a few other features. The
* support for nontemporal memory accesses is enough to make this
* worthwhile as a separate implementation.
*/
#if defined(__i386__)
#include "raid6.h"
#include "raid6x86.h"
/* Defined in raid6mmx.c */
extern const struct raid6_mmx_constants {
u64 x1d;
} raid6_mmx_constants;
static int raid6_have_sse1_or_mmxext(void)
{
#ifdef __KERNEL__
/* Not really boot_cpu but "all_cpus" */
return boot_cpu_has(X86_FEATURE_MMX) &&
(boot_cpu_has(X86_FEATURE_XMM) ||
boot_cpu_has(X86_FEATURE_MMXEXT));
#else
/* User space test code - this incorrectly breaks on some Athlons */
u32 features = cpuid_features();
return ( (features & (5<<23)) == (5<<23) );
#endif
}
/*
* Plain SSE1 implementation
*/
static void raid6_sse11_gen_syndrome(int disks, size_t bytes, void **ptrs)
{
u8 **dptr = (u8 **)ptrs;
u8 *p, *q;
int d, z, z0;
raid6_mmx_save_t sa;
z0 = disks - 3; /* Highest data disk */
p = dptr[z0+1]; /* XOR parity */
q = dptr[z0+2]; /* RS syndrome */
/* This is really MMX code, not SSE */
raid6_before_mmx(&sa);
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("prefetchnta %0" : : "m" (dptr[z0][d]));
asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
asm volatile("prefetchnta %0" : : "m" (dptr[z0-1][d]));
asm volatile("movq %mm2,%mm4"); /* Q[0] */
asm volatile("movq %0,%%mm6" : : "m" (dptr[z0-1][d]));
for ( z = z0-2 ; z >= 0 ; z-- ) {
asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
asm volatile("pcmpgtb %mm4,%mm5");
asm volatile("paddb %mm4,%mm4");
asm volatile("pand %mm0,%mm5");
asm volatile("pxor %mm5,%mm4");
asm volatile("pxor %mm5,%mm5");
asm volatile("pxor %mm6,%mm2");
asm volatile("pxor %mm6,%mm4");
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");
asm volatile("pxor %mm5,%mm5");
asm volatile("pxor %mm6,%mm2");
asm volatile("pxor %mm6,%mm4");
asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
}
raid6_after_mmx(&sa);
asm volatile("sfence" : : : "memory");
}
const struct raid6_calls raid6_sse1x1 = {
raid6_sse11_gen_syndrome,
raid6_have_sse1_or_mmxext,
"sse1x1",
1 /* Has cache hints */
};
/*
* Unrolled-by-2 SSE1 implementation
*/
static void raid6_sse12_gen_syndrome(int disks, size_t bytes, void **ptrs)
{
u8 **dptr = (u8 **)ptrs;
u8 *p, *q;
int d, z, z0;
raid6_mmx_save_t sa;
z0 = disks - 3; /* Highest data disk */
p = dptr[z0+1]; /* XOR parity */
q = dptr[z0+2]; /* RS syndrome */
raid6_before_mmx(&sa);
asm volatile("movq %0,%%mm0" : : "m" (raid6_mmx_constants.x1d));
asm volatile("pxor %mm5,%mm5"); /* Zero temp */
asm volatile("pxor %mm7,%mm7"); /* Zero temp */
/* We uniformly assume a single prefetch covers at least 16 bytes */
for ( d = 0 ; d < bytes ; d += 16 ) {
asm volatile("prefetchnta %0" : : "m" (dptr[z0][d]));
asm volatile("movq %0,%%mm2" : : "m" (dptr[z0][d])); /* P[0] */
asm volatile("movq %0,%%mm3" : : "m" (dptr[z0][d+8])); /* P[1] */
asm volatile("movq %mm2,%mm4"); /* Q[0] */
asm volatile("movq %mm3,%mm6"); /* Q[1] */
for ( z = z0-1 ; z >= 0 ; z-- ) {
asm volatile("prefetchnta %0" : : "m" (dptr[z][d]));
asm volatile("pcmpgtb %mm4,%mm5");
asm volatile("pcmpgtb %mm6,%mm7");
asm volatile("paddb %mm4,%mm4");
asm volatile("paddb %mm6,%mm6");
asm volatile("pand %mm0,%mm5");
asm volatile("pand %mm0,%mm7");
asm volatile("pxor %mm5,%mm4");
asm volatile("pxor %mm7,%mm6");
asm volatile("movq %0,%%mm5" : : "m" (dptr[z][d]));
asm volatile("movq %0,%%mm7" : : "m" (dptr[z][d+8]));
asm volatile("pxor %mm5,%mm2");
asm volatile("pxor %mm7,%mm3");
asm volatile("pxor %mm5,%mm4");
asm volatile("pxor %mm7,%mm6");
asm volatile("pxor %mm5,%mm5");
asm volatile("pxor %mm7,%mm7");
}
asm volatile("movntq %%mm2,%0" : "=m" (p[d]));
asm volatile("movntq %%mm3,%0" : "=m" (p[d+8]));
asm volatile("movntq %%mm4,%0" : "=m" (q[d]));
asm volatile("movntq %%mm6,%0" : "=m" (q[d+8]));
}
raid6_after_mmx(&sa);
asm volatile("sfence" : :: "memory");
}
const struct raid6_calls raid6_sse1x2 = {
raid6_sse12_gen_syndrome,
raid6_have_sse1_or_mmxext,
"sse1x2",
1 /* Has cache hints */
};
#endif
