// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Broadcom Starfighter 2 DSA switch CFP support
 *
 * Copyright (C) 2016, Broadcom
 */

#include <linux/list.h>
#include <linux/ethtool.h>
#include <linux/if_ether.h>
#include <linux/in.h>
#include <linux/netdevice.h>
#include <net/dsa.h>
#include <linux/bitmap.h>
#include <net/flow_offload.h>
#include <net/switchdev.h>
#include <uapi/linux/if_bridge.h>

#include "bcm_sf2.h"
#include "bcm_sf2_regs.h"

struct cfp_rule {
        int port;
        struct ethtool_rx_flow_spec fs;
        struct list_head next;
};

struct cfp_udf_slice_layout {
        u8 slices[UDFS_PER_SLICE];
        u32 mask_value;
        u32 base_offset;
};

struct cfp_udf_layout {
        struct cfp_udf_slice_layout udfs[UDF_NUM_SLICES];
};

static const u8 zero_slice[UDFS_PER_SLICE] = { };

/* UDF slices layout for a TCPv4/UDPv4 specification */
static const struct cfp_udf_layout udf_tcpip4_layout = {
        .udfs = {
                [1] = {
                        .slices = {
                                /* End of L2, byte offset 12, src IP[0:15] */
                                CFG_UDF_EOL2 | 6,
                                /* End of L2, byte offset 14, src IP[16:31] */
                                CFG_UDF_EOL2 | 7,
                                /* End of L2, byte offset 16, dst IP[0:15] */
                                CFG_UDF_EOL2 | 8,
                                /* End of L2, byte offset 18, dst IP[16:31] */
                                CFG_UDF_EOL2 | 9,
                                /* End of L3, byte offset 0, src port */
                                CFG_UDF_EOL3 | 0,
                                /* End of L3, byte offset 2, dst port */
                                CFG_UDF_EOL3 | 1,
                                0, 0, 0
                        },
                        .mask_value = L3_FRAMING_MASK | IPPROTO_MASK | IP_FRAG,
                        .base_offset = CORE_UDF_0_A_0_8_PORT_0 + UDF_SLICE_OFFSET,
                },
        },
};

/* UDF slices layout for a TCPv6/UDPv6 specification */
static const struct cfp_udf_layout udf_tcpip6_layout = {
        .udfs = {
                [0] = {
                        .slices = {
                                /* End of L2, byte offset 8, src IP[0:15] */
                                CFG_UDF_EOL2 | 4,
                                /* End of L2, byte offset 10, src IP[16:31] */
                                CFG_UDF_EOL2 | 5,
                                /* End of L2, byte offset 12, src IP[32:47] */
                                CFG_UDF_EOL2 | 6,
                                /* End of L2, byte offset 14, src IP[48:63] */
                                CFG_UDF_EOL2 | 7,
                                /* End of L2, byte offset 16, src IP[64:79] */
                                CFG_UDF_EOL2 | 8,
                                /* End of L2, byte offset 18, src IP[80:95] */
                                CFG_UDF_EOL2 | 9,
                                /* End of L2, byte offset 20, src IP[96:111] */
                                CFG_UDF_EOL2 | 10,
                                /* End of L2, byte offset 22, src IP[112:127] */
                                CFG_UDF_EOL2 | 11,
                                /* End of L3, byte offset 0, src port */
                                CFG_UDF_EOL3 | 0,
                        },
                        .mask_value = L3_FRAMING_MASK | IPPROTO_MASK | IP_FRAG,
                        .base_offset = CORE_UDF_0_B_0_8_PORT_0,
                },
                [3] = {
                        .slices = {
                                /* End of L2, byte offset 24, dst IP[0:15] */
                                CFG_UDF_EOL2 | 12,
                                /* End of L2, byte offset 26, dst IP[16:31] */
                                CFG_UDF_EOL2 | 13,
                                /* End of L2, byte offset 28, dst IP[32:47] */
                                CFG_UDF_EOL2 | 14,
                                /* End of L2, byte offset 30, dst IP[48:63] */
                                CFG_UDF_EOL2 | 15,
                                /* End of L2, byte offset 32, dst IP[64:79] */
                                CFG_UDF_EOL2 | 16,
                                /* End of L2, byte offset 34, dst IP[80:95] */
                                CFG_UDF_EOL2 | 17,
                                /* End of L2, byte offset 36, dst IP[96:111] */
                                CFG_UDF_EOL2 | 18,
                                /* End of L2, byte offset 38, dst IP[112:127] */
                                CFG_UDF_EOL2 | 19,
                                /* End of L3, byte offset 2, dst port */
                                CFG_UDF_EOL3 | 1,
                        },
                        .mask_value = L3_FRAMING_MASK | IPPROTO_MASK | IP_FRAG,
                        .base_offset = CORE_UDF_0_D_0_11_PORT_0,
                },
        },
};

static inline unsigned int bcm_sf2_get_num_udf_slices(const u8 *layout)
{
        unsigned int i, count = 0;

        for (i = 0; i < UDFS_PER_SLICE; i++) {
                if (layout[i] != 0)
                        count++;
        }

        return count;
}

static inline u32 udf_upper_bits(int num_udf)
{
        return GENMASK(num_udf - 1, 0) >> (UDFS_PER_SLICE - 1);
}

static inline u32 udf_lower_bits(int num_udf)
{
        return (u8)GENMASK(num_udf - 1, 0);
}

static unsigned int bcm_sf2_get_slice_number(const struct cfp_udf_layout *l,
                                             unsigned int start)
{
        const struct cfp_udf_slice_layout *slice_layout;
        unsigned int slice_idx;

        for (slice_idx = start; slice_idx < UDF_NUM_SLICES; slice_idx++) {
                slice_layout = &l->udfs[slice_idx];
                if (memcmp(slice_layout->slices, zero_slice,
                           sizeof(zero_slice)))
                        break;
        }

        return slice_idx;
}

static void bcm_sf2_cfp_udf_set(struct bcm_sf2_priv *priv,
                                const struct cfp_udf_layout *layout,
                                unsigned int slice_num)
{
        u32 offset = layout->udfs[slice_num].base_offset;
        unsigned int i;

        for (i = 0; i < UDFS_PER_SLICE; i++)
                core_writel(priv, layout->udfs[slice_num].slices[i],
                            offset + i * 4);
}

static int bcm_sf2_cfp_op(struct bcm_sf2_priv *priv, unsigned int op)
{
        unsigned int timeout = 1000;
        u32 reg;

        reg = core_readl(priv, CORE_CFP_ACC);
        reg &= ~(OP_SEL_MASK | RAM_SEL_MASK);
        reg |= OP_STR_DONE | op;
        core_writel(priv, reg, CORE_CFP_ACC);

        do {
                reg = core_readl(priv, CORE_CFP_ACC);
                if (!(reg & OP_STR_DONE))
                        break;

                cpu_relax();
        } while (timeout--);

        if (!timeout)
                return -ETIMEDOUT;

        return 0;
}

static inline void bcm_sf2_cfp_rule_addr_set(struct bcm_sf2_priv *priv,
                                             unsigned int addr)
{
        u32 reg;

        WARN_ON(addr >= priv->num_cfp_rules);

        reg = core_readl(priv, CORE_CFP_ACC);
        reg &= ~(XCESS_ADDR_MASK << XCESS_ADDR_SHIFT);
        reg |= addr << XCESS_ADDR_SHIFT;
        core_writel(priv, reg, CORE_CFP_ACC);
}

static inline unsigned int bcm_sf2_cfp_rule_size(struct bcm_sf2_priv *priv)
{
        /* Entry #0 is reserved */
        return priv->num_cfp_rules - 1;
}

static int bcm_sf2_cfp_act_pol_set(struct bcm_sf2_priv *priv,
                                   unsigned int rule_index,
                                   int src_port,
                                   unsigned int port_num,
                                   unsigned int queue_num,
                                   bool fwd_map_change)
{
        int ret;
        u32 reg;

        /* Replace ARL derived destination with DST_MAP derived, define
         * which port and queue this should be forwarded to.
         */
        if (fwd_map_change)
                reg = CHANGE_FWRD_MAP_IB_REP_ARL |
                      BIT(port_num + DST_MAP_IB_SHIFT) |
                      CHANGE_TC | queue_num << NEW_TC_SHIFT;
        else
                reg = 0;

        /* Enable looping back to the original port */
        if (src_port == port_num)
                reg |= LOOP_BK_EN;

        core_writel(priv, reg, CORE_ACT_POL_DATA0);

        /* Set classification ID that needs to be put in Broadcom tag */
        core_writel(priv, rule_index << CHAIN_ID_SHIFT, CORE_ACT_POL_DATA1);

        core_writel(priv, 0, CORE_ACT_POL_DATA2);

        /* Configure policer RAM now */
        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | ACT_POL_RAM);
        if (ret) {
                pr_err("Policer entry at %d failed\n", rule_index);
                return ret;
        }

        /* Disable the policer */
        core_writel(priv, POLICER_MODE_DISABLE, CORE_RATE_METER0);

        /* Now the rate meter */
        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | RATE_METER_RAM);
        if (ret) {
                pr_err("Meter entry at %d failed\n", rule_index);
                return ret;
        }

        return 0;
}

static void bcm_sf2_cfp_slice_ipv4(struct bcm_sf2_priv *priv,
                                   struct flow_dissector_key_ipv4_addrs *addrs,
                                   struct flow_dissector_key_ports *ports,
                                   const __be16 vlan_tci,
                                   unsigned int slice_num, u8 num_udf,
                                   bool mask)
{
        u32 reg, offset;

        /* UDF_Valid[7:0]       [31:24]
         * S-Tag                [23:8]
         * C-Tag                [7:0]
         */
        reg = udf_lower_bits(num_udf) << 24 | be16_to_cpu(vlan_tci) >> 8;
        if (mask)
                core_writel(priv, reg, CORE_CFP_MASK_PORT(5));
        else
                core_writel(priv, reg, CORE_CFP_DATA_PORT(5));

        /* C-Tag                [31:24]
         * UDF_n_A8             [23:8]
         * UDF_n_A7             [7:0]
         */
        reg = (u32)(be16_to_cpu(vlan_tci) & 0xff) << 24;
        if (mask)
                offset = CORE_CFP_MASK_PORT(4);
        else
                offset = CORE_CFP_DATA_PORT(4);
        core_writel(priv, reg, offset);

        /* UDF_n_A7             [31:24]
         * UDF_n_A6             [23:8]
         * UDF_n_A5             [7:0]
         */
        reg = be16_to_cpu(ports->dst) >> 8;
        if (mask)
                offset = CORE_CFP_MASK_PORT(3);
        else
                offset = CORE_CFP_DATA_PORT(3);
        core_writel(priv, reg, offset);

        /* UDF_n_A5             [31:24]
         * UDF_n_A4             [23:8]
         * UDF_n_A3             [7:0]
         */
        reg = (be16_to_cpu(ports->dst) & 0xff) << 24 |
              (u32)be16_to_cpu(ports->src) << 8 |
              (be32_to_cpu(addrs->dst) & 0x0000ff00) >> 8;
        if (mask)
                offset = CORE_CFP_MASK_PORT(2);
        else
                offset = CORE_CFP_DATA_PORT(2);
        core_writel(priv, reg, offset);

        /* UDF_n_A3             [31:24]
         * UDF_n_A2             [23:8]
         * UDF_n_A1             [7:0]
         */
        reg = (u32)(be32_to_cpu(addrs->dst) & 0xff) << 24 |
              (u32)(be32_to_cpu(addrs->dst) >> 16) << 8 |
              (be32_to_cpu(addrs->src) & 0x0000ff00) >> 8;
        if (mask)
                offset = CORE_CFP_MASK_PORT(1);
        else
                offset = CORE_CFP_DATA_PORT(1);
        core_writel(priv, reg, offset);

        /* UDF_n_A1             [31:24]
         * UDF_n_A0             [23:8]
         * Reserved             [7:4]
         * Slice ID             [3:2]
         * Slice valid          [1:0]
         */
        reg = (u32)(be32_to_cpu(addrs->src) & 0xff) << 24 |
              (u32)(be32_to_cpu(addrs->src) >> 16) << 8 |
              SLICE_NUM(slice_num) | SLICE_VALID;
        if (mask)
                offset = CORE_CFP_MASK_PORT(0);
        else
                offset = CORE_CFP_DATA_PORT(0);
        core_writel(priv, reg, offset);
}

static int bcm_sf2_cfp_ipv4_rule_set(struct bcm_sf2_priv *priv, int port,
                                     unsigned int port_num,
                                     unsigned int queue_num,
                                     struct ethtool_rx_flow_spec *fs)
{
        __be16 vlan_tci = 0, vlan_m_tci = htons(0xffff);
        struct ethtool_rx_flow_spec_input input = {};
        const struct cfp_udf_layout *layout;
        unsigned int slice_num, rule_index;
        struct ethtool_rx_flow_rule *flow;
        struct flow_match_ipv4_addrs ipv4;
        struct flow_match_ports ports;
        struct flow_match_ip ip;
        u8 ip_proto, ip_frag;
        u8 num_udf;
        u32 reg;
        int ret;

        switch (fs->flow_type & ~FLOW_EXT) {
        case TCP_V4_FLOW:
                ip_proto = IPPROTO_TCP;
                break;
        case UDP_V4_FLOW:
                ip_proto = IPPROTO_UDP;
                break;
        default:
                return -EINVAL;
        }

        ip_frag = !!(be32_to_cpu(fs->h_ext.data[0]) & 1);

        /* Extract VLAN TCI */
        if (fs->flow_type & FLOW_EXT) {
                vlan_tci = fs->h_ext.vlan_tci;
                vlan_m_tci = fs->m_ext.vlan_tci;
        }

        /* Locate the first rule available */
        if (fs->location == RX_CLS_LOC_ANY)
                rule_index = find_first_zero_bit(priv->cfp.used,
                                                 priv->num_cfp_rules);
        else
                rule_index = fs->location;

        if (rule_index > bcm_sf2_cfp_rule_size(priv))
                return -ENOSPC;

        input.fs = fs;
        flow = ethtool_rx_flow_rule_create(&input);
        if (IS_ERR(flow))
                return PTR_ERR(flow);

        flow_rule_match_ipv4_addrs(flow->rule, &ipv4);
        flow_rule_match_ports(flow->rule, &ports);
        flow_rule_match_ip(flow->rule, &ip);

        layout = &udf_tcpip4_layout;
        /* We only use one UDF slice for now */
        slice_num = bcm_sf2_get_slice_number(layout, 0);
        if (slice_num == UDF_NUM_SLICES) {
                ret = -EINVAL;
                goto out_err_flow_rule;
        }

        num_udf = bcm_sf2_get_num_udf_slices(layout->udfs[slice_num].slices);

        /* Apply the UDF layout for this filter */
        bcm_sf2_cfp_udf_set(priv, layout, slice_num);

        /* Apply to all packets received through this port */
        core_writel(priv, BIT(port), CORE_CFP_DATA_PORT(7));

        /* Source port map match */
        core_writel(priv, 0xff, CORE_CFP_MASK_PORT(7));

        /* S-Tag status         [31:30]
         * C-Tag status         [29:28]
         * L2 framing           [27:26]
         * L3 framing           [25:24]
         * IP ToS               [23:16]
         * IP proto             [15:08]
         * IP Fragm             [7]
         * Non 1st frag         [6]
         * IP Authen            [5]
         * TTL range            [4:3]
         * PPPoE session        [2]
         * Reserved             [1]
         * UDF_Valid[8]         [0]
         */
        core_writel(priv, ip.key->tos << IPTOS_SHIFT |
                    ip_proto << IPPROTO_SHIFT | ip_frag << IP_FRAG_SHIFT |
                    udf_upper_bits(num_udf),
                    CORE_CFP_DATA_PORT(6));

        /* Mask with the specific layout for IPv4 packets */
        core_writel(priv, layout->udfs[slice_num].mask_value |
                    udf_upper_bits(num_udf), CORE_CFP_MASK_PORT(6));

        /* Program the match and the mask */
        bcm_sf2_cfp_slice_ipv4(priv, ipv4.key, ports.key, vlan_tci,
                               slice_num, num_udf, false);
        bcm_sf2_cfp_slice_ipv4(priv, ipv4.mask, ports.mask, vlan_m_tci,
                               SLICE_NUM_MASK, num_udf, true);

        /* Insert into TCAM now */
        bcm_sf2_cfp_rule_addr_set(priv, rule_index);

        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | TCAM_SEL);
        if (ret) {
                pr_err("TCAM entry at addr %d failed\n", rule_index);
                goto out_err_flow_rule;
        }

        /* Insert into Action and policer RAMs now */
        ret = bcm_sf2_cfp_act_pol_set(priv, rule_index, port, port_num,
                                      queue_num, true);
        if (ret)
                goto out_err_flow_rule;

        /* Turn on CFP for this rule now */
        reg = core_readl(priv, CORE_CFP_CTL_REG);
        reg |= BIT(port);
        core_writel(priv, reg, CORE_CFP_CTL_REG);

        /* Flag the rule as being used and return it */
        set_bit(rule_index, priv->cfp.used);
        set_bit(rule_index, priv->cfp.unique);
        fs->location = rule_index;

        return 0;

out_err_flow_rule:
        ethtool_rx_flow_rule_destroy(flow);
        return ret;
}

static void bcm_sf2_cfp_slice_ipv6(struct bcm_sf2_priv *priv,
                                   const __be32 *ip6_addr, const __be16 port,
                                   const __be16 vlan_tci,
                                   unsigned int slice_num, u32 udf_bits,
                                   bool mask)
{
        u32 reg, tmp, val, offset;

        /* UDF_Valid[7:0]       [31:24]
         * S-Tag                [23:8]
         * C-Tag                [7:0]
         */
        reg = udf_bits << 24 | be16_to_cpu(vlan_tci) >> 8;
        if (mask)
                core_writel(priv, reg, CORE_CFP_MASK_PORT(5));
        else
                core_writel(priv, reg, CORE_CFP_DATA_PORT(5));

        /* C-Tag                [31:24]
         * UDF_n_B8             [23:8]  (port)
         * UDF_n_B7 (upper)     [7:0]   (addr[15:8])
         */
        reg = be32_to_cpu(ip6_addr[3]);
        val = (u32)be16_to_cpu(port) << 8 | ((reg >> 8) & 0xff);
        val |= (u32)(be16_to_cpu(vlan_tci) & 0xff) << 24;
        if (mask)
                offset = CORE_CFP_MASK_PORT(4);
        else
                offset = CORE_CFP_DATA_PORT(4);
        core_writel(priv, val, offset);

        /* UDF_n_B7 (lower)     [31:24] (addr[7:0])
         * UDF_n_B6             [23:8] (addr[31:16])
         * UDF_n_B5 (upper)     [7:0] (addr[47:40])
         */
        tmp = be32_to_cpu(ip6_addr[2]);
        val = (u32)(reg & 0xff) << 24 | (u32)(reg >> 16) << 8 |
              ((tmp >> 8) & 0xff);
        if (mask)
                offset = CORE_CFP_MASK_PORT(3);
        else
                offset = CORE_CFP_DATA_PORT(3);
        core_writel(priv, val, offset);

        /* UDF_n_B5 (lower)     [31:24] (addr[39:32])
         * UDF_n_B4             [23:8] (addr[63:48])
         * UDF_n_B3 (upper)     [7:0] (addr[79:72])
         */
        reg = be32_to_cpu(ip6_addr[1]);
        val = (u32)(tmp & 0xff) << 24 | (u32)(tmp >> 16) << 8 |
              ((reg >> 8) & 0xff);
        if (mask)
                offset = CORE_CFP_MASK_PORT(2);
        else
                offset = CORE_CFP_DATA_PORT(2);
        core_writel(priv, val, offset);

        /* UDF_n_B3 (lower)     [31:24] (addr[71:64])
         * UDF_n_B2             [23:8] (addr[95:80])
         * UDF_n_B1 (upper)     [7:0] (addr[111:104])
         */
        tmp = be32_to_cpu(ip6_addr[0]);
        val = (u32)(reg & 0xff) << 24 | (u32)(reg >> 16) << 8 |
              ((tmp >> 8) & 0xff);
        if (mask)
                offset = CORE_CFP_MASK_PORT(1);
        else
                offset = CORE_CFP_DATA_PORT(1);
        core_writel(priv, val, offset);

        /* UDF_n_B1 (lower)     [31:24] (addr[103:96])
         * UDF_n_B0             [23:8] (addr[127:112])
         * Reserved             [7:4]
         * Slice ID             [3:2]
         * Slice valid          [1:0]
         */
        reg = (u32)(tmp & 0xff) << 24 | (u32)(tmp >> 16) << 8 |
               SLICE_NUM(slice_num) | SLICE_VALID;
        if (mask)
                offset = CORE_CFP_MASK_PORT(0);
        else
                offset = CORE_CFP_DATA_PORT(0);
        core_writel(priv, reg, offset);
}

static struct cfp_rule *bcm_sf2_cfp_rule_find(struct bcm_sf2_priv *priv,
                                              int port, u32 location)
{
        struct cfp_rule *rule = NULL;

        list_for_each_entry(rule, &priv->cfp.rules_list, next) {
                if (rule->port == port && rule->fs.location == location)
                        break;
        }

        return rule;
}

static int bcm_sf2_cfp_rule_cmp(struct bcm_sf2_priv *priv, int port,
                                struct ethtool_rx_flow_spec *fs)
{
        struct cfp_rule *rule = NULL;
        size_t fs_size = 0;
        int ret = 1;

        if (list_empty(&priv->cfp.rules_list))
                return ret;

        list_for_each_entry(rule, &priv->cfp.rules_list, next) {
                ret = 1;
                if (rule->port != port)
                        continue;

                if (rule->fs.flow_type != fs->flow_type ||
                    rule->fs.ring_cookie != fs->ring_cookie ||
                    rule->fs.h_ext.data[0] != fs->h_ext.data[0])
                        continue;

                switch (fs->flow_type & ~FLOW_EXT) {
                case TCP_V6_FLOW:
                case UDP_V6_FLOW:
                        fs_size = sizeof(struct ethtool_tcpip6_spec);
                        break;
                case TCP_V4_FLOW:
                case UDP_V4_FLOW:
                        fs_size = sizeof(struct ethtool_tcpip4_spec);
                        break;
                default:
                        continue;
                }

                ret = memcmp(&rule->fs.h_u, &fs->h_u, fs_size);
                ret |= memcmp(&rule->fs.m_u, &fs->m_u, fs_size);
                /* Compare VLAN TCI values as well */
                if (rule->fs.flow_type & FLOW_EXT) {
                        ret |= rule->fs.h_ext.vlan_tci != fs->h_ext.vlan_tci;
                        ret |= rule->fs.m_ext.vlan_tci != fs->m_ext.vlan_tci;
                }
                if (ret == 0)
                        break;
        }

        return ret;
}

static int bcm_sf2_cfp_ipv6_rule_set(struct bcm_sf2_priv *priv, int port,
                                     unsigned int port_num,
                                     unsigned int queue_num,
                                     struct ethtool_rx_flow_spec *fs)
{
        __be16 vlan_tci = 0, vlan_m_tci = htons(0xffff);
        struct ethtool_rx_flow_spec_input input = {};
        unsigned int slice_num, rule_index[2];
        const struct cfp_udf_layout *layout;
        struct ethtool_rx_flow_rule *flow;
        struct flow_match_ipv6_addrs ipv6;
        struct flow_match_ports ports;
        u8 ip_proto, ip_frag;
        int ret = 0;
        u8 num_udf;
        u32 reg;

        switch (fs->flow_type & ~FLOW_EXT) {
        case TCP_V6_FLOW:
                ip_proto = IPPROTO_TCP;
                break;
        case UDP_V6_FLOW:
                ip_proto = IPPROTO_UDP;
                break;
        default:
                return -EINVAL;
        }

        ip_frag = !!(be32_to_cpu(fs->h_ext.data[0]) & 1);

        /* Extract VLAN TCI */
        if (fs->flow_type & FLOW_EXT) {
                vlan_tci = fs->h_ext.vlan_tci;
                vlan_m_tci = fs->m_ext.vlan_tci;
        }

        layout = &udf_tcpip6_layout;
        slice_num = bcm_sf2_get_slice_number(layout, 0);
        if (slice_num == UDF_NUM_SLICES)
                return -EINVAL;

        num_udf = bcm_sf2_get_num_udf_slices(layout->udfs[slice_num].slices);

        /* Negotiate two indexes, one for the second half which we are chained
         * from, which is what we will return to user-space, and a second one
         * which is used to store its first half. That first half does not
         * allow any choice of placement, so it just needs to find the next
         * available bit. We return the second half as fs->location because
         * that helps with the rule lookup later on since the second half is
         * chained from its first half, we can easily identify IPv6 CFP rules
         * by looking whether they carry a CHAIN_ID.
         *
         * We also want the second half to have a lower rule_index than its
         * first half because the HW search is by incrementing addresses.
         */
        if (fs->location == RX_CLS_LOC_ANY)
                rule_index[1] = find_first_zero_bit(priv->cfp.used,
                                                    priv->num_cfp_rules);
        else
                rule_index[1] = fs->location;
        if (rule_index[1] > bcm_sf2_cfp_rule_size(priv))
                return -ENOSPC;

        /* Flag it as used (cleared on error path) such that we can immediately
         * obtain a second one to chain from.
         */
        set_bit(rule_index[1], priv->cfp.used);

        rule_index[0] = find_first_zero_bit(priv->cfp.used,
                                            priv->num_cfp_rules);
        if (rule_index[0] > bcm_sf2_cfp_rule_size(priv)) {
                ret = -ENOSPC;
                goto out_err;
        }

        input.fs = fs;
        flow = ethtool_rx_flow_rule_create(&input);
        if (IS_ERR(flow)) {
                ret = PTR_ERR(flow);
                goto out_err;
        }
        flow_rule_match_ipv6_addrs(flow->rule, &ipv6);
        flow_rule_match_ports(flow->rule, &ports);

        /* Apply the UDF layout for this filter */
        bcm_sf2_cfp_udf_set(priv, layout, slice_num);

        /* Apply to all packets received through this port */
        core_writel(priv, BIT(port), CORE_CFP_DATA_PORT(7));

        /* Source port map match */
        core_writel(priv, 0xff, CORE_CFP_MASK_PORT(7));

        /* S-Tag status         [31:30]
         * C-Tag status         [29:28]
         * L2 framing           [27:26]
         * L3 framing           [25:24]
         * IP ToS               [23:16]
         * IP proto             [15:08]
         * IP Fragm             [7]
         * Non 1st frag         [6]
         * IP Authen            [5]
         * TTL range            [4:3]
         * PPPoE session        [2]
         * Reserved             [1]
         * UDF_Valid[8]         [0]
         */
        reg = 1 << L3_FRAMING_SHIFT | ip_proto << IPPROTO_SHIFT |
                ip_frag << IP_FRAG_SHIFT | udf_upper_bits(num_udf);
        core_writel(priv, reg, CORE_CFP_DATA_PORT(6));

        /* Mask with the specific layout for IPv6 packets including
         * UDF_Valid[8]
         */
        reg = layout->udfs[slice_num].mask_value | udf_upper_bits(num_udf);
        core_writel(priv, reg, CORE_CFP_MASK_PORT(6));

        /* Slice the IPv6 source address and port */
        bcm_sf2_cfp_slice_ipv6(priv, ipv6.key->src.in6_u.u6_addr32,
                               ports.key->src, vlan_tci, slice_num,
                               udf_lower_bits(num_udf), false);
        bcm_sf2_cfp_slice_ipv6(priv, ipv6.mask->src.in6_u.u6_addr32,
                               ports.mask->src, vlan_m_tci, SLICE_NUM_MASK,
                               udf_lower_bits(num_udf), true);

        /* Insert into TCAM now because we need to insert a second rule */
        bcm_sf2_cfp_rule_addr_set(priv, rule_index[0]);

        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | TCAM_SEL);
        if (ret) {
                pr_err("TCAM entry at addr %d failed\n", rule_index[0]);
                goto out_err_flow_rule;
        }

        /* Insert into Action and policer RAMs now */
        ret = bcm_sf2_cfp_act_pol_set(priv, rule_index[0], port, port_num,
                                      queue_num, false);
        if (ret)
                goto out_err_flow_rule;

        /* Now deal with the second slice to chain this rule */
        slice_num = bcm_sf2_get_slice_number(layout, slice_num + 1);
        if (slice_num == UDF_NUM_SLICES) {
                ret = -EINVAL;
                goto out_err_flow_rule;
        }

        num_udf = bcm_sf2_get_num_udf_slices(layout->udfs[slice_num].slices);

        /* Apply the UDF layout for this filter */
        bcm_sf2_cfp_udf_set(priv, layout, slice_num);

        /* Chained rule, source port match is coming from the rule we are
         * chained from.
         */
        core_writel(priv, 0, CORE_CFP_DATA_PORT(7));
        core_writel(priv, 0, CORE_CFP_MASK_PORT(7));

        /*
         * CHAIN ID             [31:24] chain to previous slice
         * Reserved             [23:20]
         * UDF_Valid[11:8]      [19:16]
         * UDF_Valid[7:0]       [15:8]
         * UDF_n_D11            [7:0]
         */
        reg = rule_index[0] << 24 | udf_upper_bits(num_udf) << 16 |
                udf_lower_bits(num_udf) << 8;
        core_writel(priv, reg, CORE_CFP_DATA_PORT(6));

        /* Mask all except chain ID, UDF Valid[8] and UDF Valid[7:0] */
        reg = XCESS_ADDR_MASK << 24 | udf_upper_bits(num_udf) << 16 |
                udf_lower_bits(num_udf) << 8;
        core_writel(priv, reg, CORE_CFP_MASK_PORT(6));

        bcm_sf2_cfp_slice_ipv6(priv, ipv6.key->dst.in6_u.u6_addr32,
                               ports.key->dst, 0, slice_num,
                               0, false);
        bcm_sf2_cfp_slice_ipv6(priv, ipv6.mask->dst.in6_u.u6_addr32,
                               ports.key->dst, 0, SLICE_NUM_MASK,
                               0, true);

        /* Insert into TCAM now */
        bcm_sf2_cfp_rule_addr_set(priv, rule_index[1]);

        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | TCAM_SEL);
        if (ret) {
                pr_err("TCAM entry at addr %d failed\n", rule_index[1]);
                goto out_err_flow_rule;
        }

        /* Insert into Action and policer RAMs now, set chain ID to
         * the one we are chained to
         */
        ret = bcm_sf2_cfp_act_pol_set(priv, rule_index[1], port, port_num,
                                      queue_num, true);
        if (ret)
                goto out_err_flow_rule;

        /* Turn on CFP for this rule now */
        reg = core_readl(priv, CORE_CFP_CTL_REG);
        reg |= BIT(port);
        core_writel(priv, reg, CORE_CFP_CTL_REG);

        /* Flag the second half rule as being used now, return it as the
         * location, and flag it as unique while dumping rules
         */
        set_bit(rule_index[0], priv->cfp.used);
        set_bit(rule_index[1], priv->cfp.unique);
        fs->location = rule_index[1];

        return ret;

out_err_flow_rule:
        ethtool_rx_flow_rule_destroy(flow);
out_err:
        clear_bit(rule_index[1], priv->cfp.used);
        return ret;
}

static int bcm_sf2_cfp_rule_insert(struct dsa_switch *ds, int port,
                                   struct ethtool_rx_flow_spec *fs)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        s8 cpu_port = dsa_to_port(ds, port)->cpu_dp->index;
        __u64 ring_cookie = fs->ring_cookie;
        struct switchdev_obj_port_vlan vlan;
        unsigned int queue_num, port_num;
        u16 vid;
        int ret;

        /* This rule is a Wake-on-LAN filter and we must specifically
         * target the CPU port in order for it to be working.
         */
        if (ring_cookie == RX_CLS_FLOW_WAKE)
                ring_cookie = cpu_port * SF2_NUM_EGRESS_QUEUES;

        /* We do not support discarding packets, check that the
         * destination port is enabled and that we are within the
         * number of ports supported by the switch
         */
        port_num = ring_cookie / SF2_NUM_EGRESS_QUEUES;

        if (ring_cookie == RX_CLS_FLOW_DISC ||
            !(dsa_is_user_port(ds, port_num) ||
              dsa_is_cpu_port(ds, port_num)) ||
            port_num >= priv->hw_params.num_ports)
                return -EINVAL;

        /* If the rule is matching a particular VLAN, make sure that we honor
         * the matching and have it tagged or untagged on the destination port,
         * we do this on egress with a VLAN entry. The egress tagging attribute
         * is expected to be provided in h_ext.data[1] bit 0. A 1 means untagged,
         * a 0 means tagged.
         */
        if (fs->flow_type & FLOW_EXT) {
                /* We cannot support matching multiple VLAN IDs yet */
                if ((be16_to_cpu(fs->m_ext.vlan_tci) & VLAN_VID_MASK) !=
                    VLAN_VID_MASK)
                        return -EINVAL;

                vid = be16_to_cpu(fs->h_ext.vlan_tci) & VLAN_VID_MASK;
                vlan.vid = vid;
                if (be32_to_cpu(fs->h_ext.data[1]) & 1)
                        vlan.flags = BRIDGE_VLAN_INFO_UNTAGGED;
                else
                        vlan.flags = 0;

                ret = ds->ops->port_vlan_add(ds, port_num, &vlan, NULL);
                if (ret)
                        return ret;
        }

        /*
         * We have a small oddity where Port 6 just does not have a
         * valid bit here (so we substract by one).
         */
        queue_num = ring_cookie % SF2_NUM_EGRESS_QUEUES;
        if (port_num >= 7)
                port_num -= 1;

        switch (fs->flow_type & ~FLOW_EXT) {
        case TCP_V4_FLOW:
        case UDP_V4_FLOW:
                ret = bcm_sf2_cfp_ipv4_rule_set(priv, port, port_num,
                                                queue_num, fs);
                break;
        case TCP_V6_FLOW:
        case UDP_V6_FLOW:
                ret = bcm_sf2_cfp_ipv6_rule_set(priv, port, port_num,
                                                queue_num, fs);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int bcm_sf2_cfp_rule_set(struct dsa_switch *ds, int port,
                                struct ethtool_rx_flow_spec *fs)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        struct cfp_rule *rule = NULL;
        int ret = -EINVAL;

        /* Check for unsupported extensions */
        if (fs->flow_type & FLOW_MAC_EXT)
                return -EINVAL;

        if (fs->location != RX_CLS_LOC_ANY &&
            fs->location > bcm_sf2_cfp_rule_size(priv))
                return -EINVAL;

        if ((fs->flow_type & FLOW_EXT) &&
            !(ds->ops->port_vlan_add || ds->ops->port_vlan_del))
                return -EOPNOTSUPP;

        if (fs->location != RX_CLS_LOC_ANY &&
            test_bit(fs->location, priv->cfp.used))
                return -EBUSY;

        ret = bcm_sf2_cfp_rule_cmp(priv, port, fs);
        if (ret == 0)
                return -EEXIST;

        rule = kzalloc(sizeof(*rule), GFP_KERNEL);
        if (!rule)
                return -ENOMEM;

        ret = bcm_sf2_cfp_rule_insert(ds, port, fs);
        if (ret) {
                kfree(rule);
                return ret;
        }

        rule->port = port;
        memcpy(&rule->fs, fs, sizeof(*fs));
        list_add_tail(&rule->next, &priv->cfp.rules_list);

        return ret;
}

static int bcm_sf2_cfp_rule_del_one(struct bcm_sf2_priv *priv, int port,
                                    u32 loc, u32 *next_loc)
{
        int ret;
        u32 reg;

        /* Indicate which rule we want to read */
        bcm_sf2_cfp_rule_addr_set(priv, loc);

        ret =  bcm_sf2_cfp_op(priv, OP_SEL_READ | TCAM_SEL);
        if (ret)
                return ret;

        /* Check if this is possibly an IPv6 rule that would
         * indicate we need to delete its companion rule
         * as well
         */
        reg = core_readl(priv, CORE_CFP_DATA_PORT(6));
        if (next_loc)
                *next_loc = (reg >> 24) & CHAIN_ID_MASK;

        /* Clear its valid bits */
        reg = core_readl(priv, CORE_CFP_DATA_PORT(0));
        reg &= ~SLICE_VALID;
        core_writel(priv, reg, CORE_CFP_DATA_PORT(0));

        /* Write back this entry into the TCAM now */
        ret = bcm_sf2_cfp_op(priv, OP_SEL_WRITE | TCAM_SEL);
        if (ret)
                return ret;

        clear_bit(loc, priv->cfp.used);
        clear_bit(loc, priv->cfp.unique);

        return 0;
}

static int bcm_sf2_cfp_rule_remove(struct bcm_sf2_priv *priv, int port,
                                   u32 loc)
{
        u32 next_loc = 0;
        int ret;

        ret = bcm_sf2_cfp_rule_del_one(priv, port, loc, &next_loc);
        if (ret)
                return ret;

        /* If this was an IPv6 rule, delete is companion rule too */
        if (next_loc)
                ret = bcm_sf2_cfp_rule_del_one(priv, port, next_loc, NULL);

        return ret;
}

static int bcm_sf2_cfp_rule_del(struct bcm_sf2_priv *priv, int port, u32 loc)
{
        struct cfp_rule *rule;
        int ret;

        if (loc > bcm_sf2_cfp_rule_size(priv))
                return -EINVAL;

        /* Refuse deleting unused rules, and those that are not unique since
         * that could leave IPv6 rules with one of the chained rule in the
         * table.
         */
        if (!test_bit(loc, priv->cfp.unique) || loc == 0)
                return -EINVAL;

        rule = bcm_sf2_cfp_rule_find(priv, port, loc);
        if (!rule)
                return -EINVAL;

        ret = bcm_sf2_cfp_rule_remove(priv, port, loc);

        list_del(&rule->next);
        kfree(rule);

        return ret;
}

static void bcm_sf2_invert_masks(struct ethtool_rx_flow_spec *flow)
{
        unsigned int i;

        for (i = 0; i < sizeof(flow->m_u); i++)
                flow->m_u.hdata[i] ^= 0xff;

        flow->m_ext.vlan_etype ^= cpu_to_be16(~0);
        flow->m_ext.vlan_tci ^= cpu_to_be16(~0);
        flow->m_ext.data[0] ^= cpu_to_be32(~0);
        flow->m_ext.data[1] ^= cpu_to_be32(~0);
}

static int bcm_sf2_cfp_rule_get(struct bcm_sf2_priv *priv, int port,
                                struct ethtool_rxnfc *nfc)
{
        struct cfp_rule *rule;

        rule = bcm_sf2_cfp_rule_find(priv, port, nfc->fs.location);
        if (!rule)
                return -EINVAL;

        memcpy(&nfc->fs, &rule->fs, sizeof(rule->fs));

        bcm_sf2_invert_masks(&nfc->fs);

        /* Put the TCAM size here */
        nfc->data = bcm_sf2_cfp_rule_size(priv);

        return 0;
}

/* We implement the search doing a TCAM search operation */
static int bcm_sf2_cfp_rule_get_all(struct bcm_sf2_priv *priv,
                                    int port, struct ethtool_rxnfc *nfc,
                                    u32 *rule_locs)
{
        unsigned int index = 1, rules_cnt = 0;

        for_each_set_bit_from(index, priv->cfp.unique, priv->num_cfp_rules) {
                rule_locs[rules_cnt] = index;
                rules_cnt++;
        }

        /* Put the TCAM size here */
        nfc->data = bcm_sf2_cfp_rule_size(priv);
        nfc->rule_cnt = rules_cnt;

        return 0;
}

int bcm_sf2_get_rxnfc(struct dsa_switch *ds, int port,
                      struct ethtool_rxnfc *nfc, u32 *rule_locs)
{
        struct net_device *p = dsa_to_port(ds, port)->cpu_dp->master;
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        int ret = 0;

        mutex_lock(&priv->cfp.lock);

        switch (nfc->cmd) {
        case ETHTOOL_GRXCLSRLCNT:
                /* Subtract the default, unusable rule */
                nfc->rule_cnt = bitmap_weight(priv->cfp.unique,
                                              priv->num_cfp_rules) - 1;
                /* We support specifying rule locations */
                nfc->data |= RX_CLS_LOC_SPECIAL;
                break;
        case ETHTOOL_GRXCLSRULE:
                ret = bcm_sf2_cfp_rule_get(priv, port, nfc);
                break;
        case ETHTOOL_GRXCLSRLALL:
                ret = bcm_sf2_cfp_rule_get_all(priv, port, nfc, rule_locs);
                break;
        default:
                ret = -EOPNOTSUPP;
                break;
        }

        mutex_unlock(&priv->cfp.lock);

        if (ret)
                return ret;

        /* Pass up the commands to the attached master network device */
        if (p->ethtool_ops->get_rxnfc) {
                ret = p->ethtool_ops->get_rxnfc(p, nfc, rule_locs);
                if (ret == -EOPNOTSUPP)
                        ret = 0;
        }

        return ret;
}

int bcm_sf2_set_rxnfc(struct dsa_switch *ds, int port,
                      struct ethtool_rxnfc *nfc)
{
        struct net_device *p = dsa_to_port(ds, port)->cpu_dp->master;
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        int ret = 0;

        mutex_lock(&priv->cfp.lock);

        switch (nfc->cmd) {
        case ETHTOOL_SRXCLSRLINS:
                ret = bcm_sf2_cfp_rule_set(ds, port, &nfc->fs);
                break;

        case ETHTOOL_SRXCLSRLDEL:
                ret = bcm_sf2_cfp_rule_del(priv, port, nfc->fs.location);
                break;
        default:
                ret = -EOPNOTSUPP;
                break;
        }

        mutex_unlock(&priv->cfp.lock);

        if (ret)
                return ret;

        /* Pass up the commands to the attached master network device.
         * This can fail, so rollback the operation if we need to.
         */
        if (p->ethtool_ops->set_rxnfc) {
                ret = p->ethtool_ops->set_rxnfc(p, nfc);
                if (ret && ret != -EOPNOTSUPP) {
                        mutex_lock(&priv->cfp.lock);
                        bcm_sf2_cfp_rule_del(priv, port, nfc->fs.location);
                        mutex_unlock(&priv->cfp.lock);
                } else {
                        ret = 0;
                }
        }

        return ret;
}

int bcm_sf2_cfp_rst(struct bcm_sf2_priv *priv)
{
        unsigned int timeout = 1000;
        u32 reg;

        reg = core_readl(priv, CORE_CFP_ACC);
        reg |= TCAM_RESET;
        core_writel(priv, reg, CORE_CFP_ACC);

        do {
                reg = core_readl(priv, CORE_CFP_ACC);
                if (!(reg & TCAM_RESET))
                        break;

                cpu_relax();
        } while (timeout--);

        if (!timeout)
                return -ETIMEDOUT;

        return 0;
}

void bcm_sf2_cfp_exit(struct dsa_switch *ds)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        struct cfp_rule *rule, *n;

        if (list_empty(&priv->cfp.rules_list))
                return;

        list_for_each_entry_safe_reverse(rule, n, &priv->cfp.rules_list, next)
                bcm_sf2_cfp_rule_del(priv, rule->port, rule->fs.location);
}

int bcm_sf2_cfp_resume(struct dsa_switch *ds)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        struct cfp_rule *rule;
        int ret = 0;
        u32 reg;

        if (list_empty(&priv->cfp.rules_list))
                return ret;

        reg = core_readl(priv, CORE_CFP_CTL_REG);
        reg &= ~CFP_EN_MAP_MASK;
        core_writel(priv, reg, CORE_CFP_CTL_REG);

        ret = bcm_sf2_cfp_rst(priv);
        if (ret)
                return ret;

        list_for_each_entry(rule, &priv->cfp.rules_list, next) {
                ret = bcm_sf2_cfp_rule_remove(priv, rule->port,
                                              rule->fs.location);
                if (ret) {
                        dev_err(ds->dev, "failed to remove rule\n");
                        return ret;
                }

                ret = bcm_sf2_cfp_rule_insert(ds, rule->port, &rule->fs);
                if (ret) {
                        dev_err(ds->dev, "failed to restore rule\n");
                        return ret;
                }
        }

        return ret;
}

static const struct bcm_sf2_cfp_stat {
        unsigned int offset;
        unsigned int ram_loc;
        const char *name;
} bcm_sf2_cfp_stats[] = {
        {
                .offset = CORE_STAT_GREEN_CNTR,
                .ram_loc = GREEN_STAT_RAM,
                .name = "Green"
        },
        {
                .offset = CORE_STAT_YELLOW_CNTR,
                .ram_loc = YELLOW_STAT_RAM,
                .name = "Yellow"
        },
        {
                .offset = CORE_STAT_RED_CNTR,
                .ram_loc = RED_STAT_RAM,
                .name = "Red"
        },
};

void bcm_sf2_cfp_get_strings(struct dsa_switch *ds, int port,
                             u32 stringset, uint8_t *data)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        unsigned int s = ARRAY_SIZE(bcm_sf2_cfp_stats);
        char buf[ETH_GSTRING_LEN];
        unsigned int i, j, iter;

        if (stringset != ETH_SS_STATS)
                return;

        for (i = 1; i < priv->num_cfp_rules; i++) {
                for (j = 0; j < s; j++) {
                        snprintf(buf, sizeof(buf),
                                 "CFP%03d_%sCntr",
                                 i, bcm_sf2_cfp_stats[j].name);
                        iter = (i - 1) * s + j;
                        strlcpy(data + iter * ETH_GSTRING_LEN,
                                buf, ETH_GSTRING_LEN);
                }
        }
}

void bcm_sf2_cfp_get_ethtool_stats(struct dsa_switch *ds, int port,
                                   uint64_t *data)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
        unsigned int s = ARRAY_SIZE(bcm_sf2_cfp_stats);
        const struct bcm_sf2_cfp_stat *stat;
        unsigned int i, j, iter;
        struct cfp_rule *rule;
        int ret;

        mutex_lock(&priv->cfp.lock);
        for (i = 1; i < priv->num_cfp_rules; i++) {
                rule = bcm_sf2_cfp_rule_find(priv, port, i);
                if (!rule)
                        continue;

                for (j = 0; j < s; j++) {
                        stat = &bcm_sf2_cfp_stats[j];

                        bcm_sf2_cfp_rule_addr_set(priv, i);
                        ret = bcm_sf2_cfp_op(priv, stat->ram_loc | OP_SEL_READ);
                        if (ret)
                                continue;

                        iter = (i - 1) * s + j;
                        data[iter] = core_readl(priv, stat->offset);
                }

        }
        mutex_unlock(&priv->cfp.lock);
}

int bcm_sf2_cfp_get_sset_count(struct dsa_switch *ds, int port, int sset)
{
        struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);

        if (sset != ETH_SS_STATS)
                return 0;

        /* 3 counters per CFP rules */
        return (priv->num_cfp_rules - 1) * ARRAY_SIZE(bcm_sf2_cfp_stats);
}