/*
 * SPDX-License-Identifier: BSD-3-Clause
 * Copyright (C) IBM Corporation 2016.
 */

#include "acl_run.h"
#include "acl_vect.h"

struct _altivec_acl_const {
        rte_xmm_t xmm_shuffle_input;
        rte_xmm_t xmm_index_mask;
        rte_xmm_t xmm_ones_16;
        rte_xmm_t range_base;
} altivec_acl_const __rte_cache_aligned = {
        {
                .u32 = {0x00000000, 0x04040404, 0x08080808, 0x0c0c0c0c}
        },
        {
                .u32 = {RTE_ACL_NODE_INDEX, RTE_ACL_NODE_INDEX,
                RTE_ACL_NODE_INDEX, RTE_ACL_NODE_INDEX}
        },
        {
                .u16 = {1, 1, 1, 1, 1, 1, 1, 1}
        },
        {
                .u32 = {0xffffff00, 0xffffff04, 0xffffff08, 0xffffff0c}
        },
};

/*
 * Resolve priority for multiple results (altivec version).
 * This consists comparing the priority of the current traversal with the
 * running set of results for the packet.
 * For each result, keep a running array of the result (rule number) and
 * its priority for each category.
 */
static inline void
resolve_priority_altivec(uint64_t transition, int n,
        const struct rte_acl_ctx *ctx, struct parms *parms,
        const struct rte_acl_match_results *p, uint32_t categories)
{
        uint32_t x;
        xmm_t results, priority, results1, priority1;
        vector bool int selector;
        xmm_t *saved_results, *saved_priority;

        for (x = 0; x < categories; x += RTE_ACL_RESULTS_MULTIPLIER) {

                saved_results = (xmm_t *)(&parms[n].cmplt->results[x]);
                saved_priority =
                        (xmm_t *)(&parms[n].cmplt->priority[x]);

                /* get results and priorities for completed trie */
                results = *(const xmm_t *)&p[transition].results[x];
                priority = *(const xmm_t *)&p[transition].priority[x];

                /* if this is not the first completed trie */
                if (parms[n].cmplt->count != ctx->num_tries) {

                        /* get running best results and their priorities */
                        results1 = *saved_results;
                        priority1 = *saved_priority;

                        /* select results that are highest priority */
                        selector = vec_cmpgt(priority1, priority);
                        results = vec_sel(results, results1, selector);
                        priority = vec_sel(priority, priority1,
                                selector);
                }

                /* save running best results and their priorities */
                *saved_results = results;
                *saved_priority = priority;
        }
}

/*
 * Check for any match in 4 transitions
 */
static __rte_always_inline uint32_t
check_any_match_x4(uint64_t val[])
{
        return (val[0] | val[1] | val[2] | val[3]) & RTE_ACL_NODE_MATCH;
}

static __rte_always_inline void
acl_match_check_x4(int slot, const struct rte_acl_ctx *ctx, struct parms *parms,
        struct acl_flow_data *flows, uint64_t transitions[])
{
        while (check_any_match_x4(transitions)) {
                transitions[0] = acl_match_check(transitions[0], slot, ctx,
                        parms, flows, resolve_priority_altivec);
                transitions[1] = acl_match_check(transitions[1], slot + 1, ctx,
                        parms, flows, resolve_priority_altivec);
                transitions[2] = acl_match_check(transitions[2], slot + 2, ctx,
                        parms, flows, resolve_priority_altivec);
                transitions[3] = acl_match_check(transitions[3], slot + 3, ctx,
                        parms, flows, resolve_priority_altivec);
        }
}

/*
 * Process 4 transitions (in 2 XMM registers) in parallel
 */
static inline __attribute__((optimize("O2"))) xmm_t
transition4(xmm_t next_input, const uint64_t *trans,
        xmm_t *indices1, xmm_t *indices2)
{
        xmm_t addr, tr_lo, tr_hi;
        xmm_t in, node_type, r, t;
        xmm_t dfa_ofs, quad_ofs;
        xmm_t *index_mask, *tp;
        vector bool int dfa_msk;
        vector signed char zeroes = {};
        union {
                uint64_t d64[2];
                uint32_t d32[4];
        } v;

        /* Move low 32 into tr_lo and high 32 into tr_hi */
        tr_lo = (xmm_t){(*indices1)[0], (*indices1)[2],
                        (*indices2)[0], (*indices2)[2]};
        tr_hi = (xmm_t){(*indices1)[1], (*indices1)[3],
                        (*indices2)[1], (*indices2)[3]};

         /* Calculate the address (array index) for all 4 transitions. */
        index_mask = (xmm_t *)&altivec_acl_const.xmm_index_mask.u32;
        t = vec_xor(*index_mask, *index_mask);
        in = vec_perm(next_input, (xmm_t){},
                *(vector unsigned char *)&altivec_acl_const.xmm_shuffle_input);

        /* Calc node type and node addr */
        node_type = vec_and(vec_nor(*index_mask, *index_mask), tr_lo);
        addr = vec_and(tr_lo, *index_mask);

        /* mask for DFA type(0) nodes */
        dfa_msk = vec_cmpeq(node_type, t);

        /* DFA calculations. */
        r = vec_sr(in, (vector unsigned int){30, 30, 30, 30});
        tp = (xmm_t *)&altivec_acl_const.range_base.u32;
        r = vec_add(r, *tp);
        t = vec_sr(in, (vector unsigned int){24, 24, 24, 24});
        r = vec_perm(tr_hi, (xmm_t){(uint16_t)0 << 16},
                (vector unsigned char)r);

        dfa_ofs = vec_sub(t, r);

        /* QUAD/SINGLE caluclations. */
        t = (xmm_t)vec_cmpgt((vector signed char)in, (vector signed char)tr_hi);
        t = (xmm_t)vec_sel(
                vec_sel(
                        (vector signed char)vec_sub(
                                zeroes, (vector signed char)t),
                        (vector signed char)t,
                        vec_cmpgt((vector signed char)t, zeroes)),
                zeroes,
                vec_cmpeq((vector signed char)t, zeroes));

        t = (xmm_t)vec_msum((vector signed char)t,
                (vector unsigned char)t, (xmm_t){});
        quad_ofs = (xmm_t)vec_msum((vector signed short)t,
                *(vector signed short *)&altivec_acl_const.xmm_ones_16.u16,
                (xmm_t){});

        /* blend DFA and QUAD/SINGLE. */
        t = vec_sel(quad_ofs, dfa_ofs, dfa_msk);

        /* calculate address for next transitions. */
        addr = vec_add(addr, t);

        v.d64[0] = (uint64_t)trans[addr[0]];
        v.d64[1] = (uint64_t)trans[addr[1]];
        *indices1 = (xmm_t){v.d32[0], v.d32[1], v.d32[2], v.d32[3]};
        v.d64[0] = (uint64_t)trans[addr[2]];
        v.d64[1] = (uint64_t)trans[addr[3]];
        *indices2 = (xmm_t){v.d32[0], v.d32[1], v.d32[2], v.d32[3]};

        return vec_sr(next_input,
                (vector unsigned int){CHAR_BIT, CHAR_BIT, CHAR_BIT, CHAR_BIT});
}

/*
 * Execute trie traversal with 8 traversals in parallel
 */
static inline int
search_altivec_8(const struct rte_acl_ctx *ctx, const uint8_t **data,
        uint32_t *results, uint32_t total_packets, uint32_t categories)
{
        int n;
        struct acl_flow_data flows;
        uint64_t index_array[MAX_SEARCHES_ALTIVEC8];
        struct completion cmplt[MAX_SEARCHES_ALTIVEC8];
        struct parms parms[MAX_SEARCHES_ALTIVEC8];
        xmm_t input0, input1;

        acl_set_flow(&flows, cmplt, RTE_DIM(cmplt), data, results,
                total_packets, categories, ctx->trans_table);

        for (n = 0; n < MAX_SEARCHES_ALTIVEC8; n++) {
                cmplt[n].count = 0;
                index_array[n] = acl_start_next_trie(&flows, parms, n, ctx);
        }

         /* Check for any matches. */
        acl_match_check_x4(0, ctx, parms, &flows, (uint64_t *)&index_array[0]);
        acl_match_check_x4(4, ctx, parms, &flows, (uint64_t *)&index_array[4]);

        while (flows.started > 0) {

                /* Gather 4 bytes of input data for each stream. */
                input0 = (xmm_t){GET_NEXT_4BYTES(parms, 0),
                                GET_NEXT_4BYTES(parms, 1),
                                GET_NEXT_4BYTES(parms, 2),
                                GET_NEXT_4BYTES(parms, 3)};

                input1 = (xmm_t){GET_NEXT_4BYTES(parms, 4),
                                GET_NEXT_4BYTES(parms, 5),
                                GET_NEXT_4BYTES(parms, 6),
                                GET_NEXT_4BYTES(parms, 7)};

                 /* Process the 4 bytes of input on each stream. */

                input0 = transition4(input0, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input1 = transition4(input1, flows.trans,
                        (xmm_t *)&index_array[4], (xmm_t *)&index_array[6]);

                input0 = transition4(input0, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input1 = transition4(input1, flows.trans,
                        (xmm_t *)&index_array[4], (xmm_t *)&index_array[6]);

                input0 = transition4(input0, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input1 = transition4(input1, flows.trans,
                        (xmm_t *)&index_array[4], (xmm_t *)&index_array[6]);

                input0 = transition4(input0, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input1 = transition4(input1, flows.trans,
                        (xmm_t *)&index_array[4], (xmm_t *)&index_array[6]);

                 /* Check for any matches. */
                acl_match_check_x4(0, ctx, parms, &flows,
                        (uint64_t *)&index_array[0]);
                acl_match_check_x4(4, ctx, parms, &flows,
                        (uint64_t *)&index_array[4]);
        }

        return 0;
}

/*
 * Execute trie traversal with 4 traversals in parallel
 */
static inline int
search_altivec_4(const struct rte_acl_ctx *ctx, const uint8_t **data,
         uint32_t *results, int total_packets, uint32_t categories)
{
        int n;
        struct acl_flow_data flows;
        uint64_t index_array[MAX_SEARCHES_ALTIVEC4];
        struct completion cmplt[MAX_SEARCHES_ALTIVEC4];
        struct parms parms[MAX_SEARCHES_ALTIVEC4];
        xmm_t input;

        acl_set_flow(&flows, cmplt, RTE_DIM(cmplt), data, results,
                total_packets, categories, ctx->trans_table);

        for (n = 0; n < MAX_SEARCHES_ALTIVEC4; n++) {
                cmplt[n].count = 0;
                index_array[n] = acl_start_next_trie(&flows, parms, n, ctx);
        }

        /* Check for any matches. */
        acl_match_check_x4(0, ctx, parms, &flows, index_array);

        while (flows.started > 0) {

                /* Gather 4 bytes of input data for each stream. */
                input = (xmm_t){GET_NEXT_4BYTES(parms, 0),
                                GET_NEXT_4BYTES(parms, 1),
                                GET_NEXT_4BYTES(parms, 2),
                                GET_NEXT_4BYTES(parms, 3)};

                /* Process the 4 bytes of input on each stream. */
                input = transition4(input, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input = transition4(input, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input = transition4(input, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);
                input = transition4(input, flows.trans,
                        (xmm_t *)&index_array[0], (xmm_t *)&index_array[2]);

                /* Check for any matches. */
                acl_match_check_x4(0, ctx, parms, &flows, index_array);
        }

        return 0;
}