// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Intel Corporation
 * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org>
 */

#include <linux/raid/pq.h>

#ifdef __KERNEL__
#include <asm/simd.h>
#include "neon.h"
#else
#define scoped_ksimd()
#define cpu_has_neon()          (1)
#endif

static int raid6_has_neon(void)
{
        return cpu_has_neon();
}

static void raid6_2data_recov_neon(int disks, size_t bytes, int faila,
                int failb, void **ptrs)
{
        u8 *p, *q, *dp, *dq;
        const u8 *pbmul;        /* P multiplier table for B data */
        const u8 *qmul;         /* Q multiplier table (for both) */

        p = (u8 *)ptrs[disks - 2];
        q = (u8 *)ptrs[disks - 1];

        /*
         * Compute syndrome with zero for the missing data pages
         * Use the dead data pages as temporary storage for
         * delta p and delta q
         */
        dp = (u8 *)ptrs[faila];
        ptrs[faila] = raid6_get_zero_page();
        ptrs[disks - 2] = dp;
        dq = (u8 *)ptrs[failb];
        ptrs[failb] = raid6_get_zero_page();
        ptrs[disks - 1] = dq;

        raid6_call.gen_syndrome(disks, bytes, ptrs);

        /* Restore pointer table */
        ptrs[faila]     = dp;
        ptrs[failb]     = dq;
        ptrs[disks - 2] = p;
        ptrs[disks - 1] = q;

        /* Now, pick the proper data tables */
        pbmul = raid6_vgfmul[raid6_gfexi[failb-faila]];
        qmul  = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila] ^
                                         raid6_gfexp[failb]]];

        scoped_ksimd()
                __raid6_2data_recov_neon(bytes, p, q, dp, dq, pbmul, qmul);
}

static void raid6_datap_recov_neon(int disks, size_t bytes, int faila,
                void **ptrs)
{
        u8 *p, *q, *dq;
        const u8 *qmul;         /* Q multiplier table */

        p = (u8 *)ptrs[disks - 2];
        q = (u8 *)ptrs[disks - 1];

        /*
         * Compute syndrome with zero for the missing data page
         * Use the dead data page as temporary storage for delta q
         */
        dq = (u8 *)ptrs[faila];
        ptrs[faila] = raid6_get_zero_page();
        ptrs[disks - 1] = dq;

        raid6_call.gen_syndrome(disks, bytes, ptrs);

        /* Restore pointer table */
        ptrs[faila]     = dq;
        ptrs[disks - 1] = q;

        /* Now, pick the proper data tables */
        qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila]]];

        scoped_ksimd()
                __raid6_datap_recov_neon(bytes, p, q, dq, qmul);
}

const struct raid6_recov_calls raid6_recov_neon = {
        .data2          = raid6_2data_recov_neon,
        .datap          = raid6_datap_recov_neon,
        .valid          = raid6_has_neon,
        .name           = "neon",
        .priority       = 10,
};