Revert "unicode: Don't special case ignorable code points"

[linux.git] / drivers / net / dsa / microchip / ksz9477_acl.c

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2023 Pengutronix, Oleksij Rempel <kernel@pengutronix.de>

/* Access Control List (ACL) structure:
 *
 * There are multiple groups of registers involved in ACL configuration:
 *
 * - Matching Rules: These registers define the criteria for matching incoming
 *   packets based on their header information (Layer 2 MAC, Layer 3 IP, or
 *   Layer 4 TCP/UDP). Different register settings are used depending on the
 *   matching rule mode (MD) and the Enable (ENB) settings.
 *
 * - Action Rules: These registers define how the ACL should modify the packet's
 *   priority, VLAN tag priority, and forwarding map once a matching rule has
 *   been triggered. The settings vary depending on whether the matching rule is
 *   in Count Mode (MD = 01 and ENB = 00) or not.
 *
 * - Processing Rules: These registers control the overall behavior of the ACL,
 *   such as selecting which matching rule to apply first, enabling/disabling
 *   specific rules, or specifying actions for matched packets.
 *
 * ACL Structure:
 *                             +----------------------+
 * +----------------------+    |    (optional)        |
 * |    Matching Rules    |    |    Matching Rules    |
 * |    (Layer 2, 3, 4)   |    |    (Layer 2, 3, 4)   |
 * +----------------------+    +----------------------+
 *             |                            |
 *             \___________________________/
 *                          v
 *               +----------------------+
 *               |   Processing Rules   |
 *               | (action idx,         |
 *               | matching rule set)   |
 *               +----------------------+
 *                          |
 *                          v
 *               +----------------------+
 *               |    Action Rules      |
 *               | (Modify Priority,    |
 *               |  Forwarding Map,     |
 *               |  VLAN tag, etc)      |
 *               +----------------------+
 */

#include <linux/bitops.h>

#include "ksz9477.h"
#include "ksz9477_reg.h"
#include "ksz_common.h"

#define KSZ9477_PORT_ACL_0              0x600

enum ksz9477_acl_port_access {
        KSZ9477_ACL_PORT_ACCESS_0  = 0x00,
        KSZ9477_ACL_PORT_ACCESS_1  = 0x01,
        KSZ9477_ACL_PORT_ACCESS_2  = 0x02,
        KSZ9477_ACL_PORT_ACCESS_3  = 0x03,
        KSZ9477_ACL_PORT_ACCESS_4  = 0x04,
        KSZ9477_ACL_PORT_ACCESS_5  = 0x05,
        KSZ9477_ACL_PORT_ACCESS_6  = 0x06,
        KSZ9477_ACL_PORT_ACCESS_7  = 0x07,
        KSZ9477_ACL_PORT_ACCESS_8  = 0x08,
        KSZ9477_ACL_PORT_ACCESS_9  = 0x09,
        KSZ9477_ACL_PORT_ACCESS_A  = 0x0A,
        KSZ9477_ACL_PORT_ACCESS_B  = 0x0B,
        KSZ9477_ACL_PORT_ACCESS_C  = 0x0C,
        KSZ9477_ACL_PORT_ACCESS_D  = 0x0D,
        KSZ9477_ACL_PORT_ACCESS_E  = 0x0E,
        KSZ9477_ACL_PORT_ACCESS_F  = 0x0F,
        KSZ9477_ACL_PORT_ACCESS_10 = 0x10,
        KSZ9477_ACL_PORT_ACCESS_11 = 0x11
};

#define KSZ9477_ACL_MD_MASK                     GENMASK(5, 4)
#define KSZ9477_ACL_MD_DISABLE                  0
#define KSZ9477_ACL_MD_L2_MAC                   1
#define KSZ9477_ACL_MD_L3_IP                    2
#define KSZ9477_ACL_MD_L4_TCP_UDP               3

#define KSZ9477_ACL_ENB_MASK                    GENMASK(3, 2)
#define KSZ9477_ACL_ENB_L2_COUNTER              0
#define KSZ9477_ACL_ENB_L2_TYPE                 1
#define KSZ9477_ACL_ENB_L2_MAC                  2
#define KSZ9477_ACL_ENB_L2_MAC_TYPE             3

/* only IPv4 src or dst can be used with mask */
#define KSZ9477_ACL_ENB_L3_IPV4_ADDR_MASK       1
/* only IPv4 src and dst can be used without mask */
#define KSZ9477_ACL_ENB_L3_IPV4_ADDR_SRC_DST    2

#define KSZ9477_ACL_ENB_L4_IP_PROTO             0
#define KSZ9477_ACL_ENB_L4_TCP_SRC_DST_PORT     1
#define KSZ9477_ACL_ENB_L4_UDP_SRC_DST_PORT     2
#define KSZ9477_ACL_ENB_L4_TCP_SEQ_NUMBER       3

#define KSZ9477_ACL_SD_SRC                      BIT(1)
#define KSZ9477_ACL_SD_DST                      0
#define KSZ9477_ACL_EQ_EQUAL                    BIT(0)
#define KSZ9477_ACL_EQ_NOT_EQUAL                0

#define KSZ9477_ACL_PM_M                        GENMASK(7, 6)
#define KSZ9477_ACL_PM_DISABLE                  0
#define KSZ9477_ACL_PM_HIGHER                   1
#define KSZ9477_ACL_PM_LOWER                    2
#define KSZ9477_ACL_PM_REPLACE                  3
#define KSZ9477_ACL_P_M                         GENMASK(5, 3)

#define KSZ9477_PORT_ACL_CTRL_0                 0x0612

#define KSZ9477_ACL_WRITE_DONE                  BIT(6)
#define KSZ9477_ACL_READ_DONE                   BIT(5)
#define KSZ9477_ACL_WRITE                       BIT(4)
#define KSZ9477_ACL_INDEX_M                     GENMASK(3, 0)

/**
 * ksz9477_dump_acl_index - Print the ACL entry at the specified index
 *
 * @dev: Pointer to the ksz9477 device structure.
 * @acle: Pointer to the ACL entry array.
 * @index: The index of the ACL entry to print.
 *
 * This function prints the details of an ACL entry, located at a particular
 * index within the ksz9477 device's ACL table. It omits printing entries that
 * are empty.
 *
 * Return: 1 if the entry is non-empty and printed, 0 otherwise.
 */
static int ksz9477_dump_acl_index(struct ksz_device *dev,
                                  struct ksz9477_acl_entry *acle, int index)
{
        bool empty = true;
        char buf[64];
        u8 *entry;
        int i;

        entry = &acle[index].entry[0];
        for (i = 0; i <= KSZ9477_ACL_PORT_ACCESS_11; i++) {
                if (entry[i])
                        empty = false;

                sprintf(buf + (i * 3), "%02x ", entry[i]);
        }

        /* no need to print empty entries */
        if (empty)
                return 0;

        dev_err(dev->dev, " Entry %02d, prio: %02d : %s", index,
                acle[index].prio, buf);

        return 1;
}

/**
 * ksz9477_dump_acl - Print ACL entries
 *
 * @dev: Pointer to the device structure.
 * @acle: Pointer to the ACL entry array.
 */
static void ksz9477_dump_acl(struct ksz_device *dev,
                             struct ksz9477_acl_entry *acle)
{
        int count = 0;
        int i;

        for (i = 0; i < KSZ9477_ACL_MAX_ENTRIES; i++)
                count += ksz9477_dump_acl_index(dev, acle, i);

        if (count != KSZ9477_ACL_MAX_ENTRIES - 1)
                dev_err(dev->dev, " Empty ACL entries were skipped\n");
}

/**
 * ksz9477_acl_is_valid_matching_rule - Check if an ACL entry contains a valid
 *                                      matching rule.
 *
 * @entry: Pointer to ACL entry buffer
 *
 * This function checks if the given ACL entry buffer contains a valid
 * matching rule by inspecting the Mode (MD) and Enable (ENB) fields.
 *
 * Returns: True if it's a valid matching rule, false otherwise.
 */
static bool ksz9477_acl_is_valid_matching_rule(u8 *entry)
{
        u8 val1, md, enb;

        val1 = entry[KSZ9477_ACL_PORT_ACCESS_1];

        md = FIELD_GET(KSZ9477_ACL_MD_MASK, val1);
        if (md == KSZ9477_ACL_MD_DISABLE)
                return false;

        if (md == KSZ9477_ACL_MD_L2_MAC) {
                /* L2 counter is not support, so it is not valid rule for now */
                enb = FIELD_GET(KSZ9477_ACL_ENB_MASK, val1);
                if (enb == KSZ9477_ACL_ENB_L2_COUNTER)
                        return false;
        }

        return true;
}

/**
 * ksz9477_acl_get_cont_entr - Get count of contiguous ACL entries and validate
 *                             the matching rules.
 * @dev: Pointer to the KSZ9477 device structure.
 * @port: Port number.
 * @index: Index of the starting ACL entry.
 *
 * Based on the KSZ9477 switch's Access Control List (ACL) system, the RuleSet
 * in an ACL entry indicates which entries contain Matching rules linked to it.
 * This RuleSet is represented by two registers: KSZ9477_ACL_PORT_ACCESS_E and
 * KSZ9477_ACL_PORT_ACCESS_F. Each bit set in these registers corresponds to
 * an entry containing a Matching rule for this RuleSet.
 *
 * For a single Matching rule linked, only one bit is set. However, when an
 * entry links multiple Matching rules, forming what's termed a 'complex rule',
 * multiple bits are set in these registers.
 *
 * This function checks that, for complex rules, the entries containing the
 * linked Matching rules are contiguous in terms of their indices. It calculates
 * and returns the number of these contiguous entries.
 *
 * Returns:
 *    - 0 if the entry is empty and can be safely overwritten
 *    - 1 if the entry represents a simple rule
 *    - The number of contiguous entries if it is the root entry of a complex
 *      rule
 *    - -ENOTEMPTY if the entry is part of a complex rule but not the root
 *      entry
 *    - -EINVAL if the validation fails
 */
static int ksz9477_acl_get_cont_entr(struct ksz_device *dev, int port,
                                     int index)
{
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        int start_idx, end_idx, contiguous_count;
        unsigned long val;
        u8 vale, valf;
        u8 *entry;
        int i;

        entry = &acles->entries[index].entry[0];
        vale = entry[KSZ9477_ACL_PORT_ACCESS_E];
        valf = entry[KSZ9477_ACL_PORT_ACCESS_F];

        val = (vale << 8) | valf;

        /* If no bits are set, return an appropriate value or error */
        if (!val) {
                if (ksz9477_acl_is_valid_matching_rule(entry)) {
                        /* Looks like we are about to corrupt some complex rule.
                         * Do not print an error here, as this is a normal case
                         * when we are trying to find a free or starting entry.
                         */
                        dev_dbg(dev->dev, "ACL: entry %d starting with a valid matching rule, but no bits set in RuleSet\n",
                                index);
                        return -ENOTEMPTY;
                }

                /* This entry does not contain a valid matching rule */
                return 0;
        }

        start_idx = find_first_bit((unsigned long *)&val, 16);
        end_idx = find_last_bit((unsigned long *)&val, 16);

        /* Calculate the contiguous count */
        contiguous_count = end_idx - start_idx + 1;

        /* Check if the number of bits set in val matches our calculated count */
        if (contiguous_count != hweight16(val)) {
                /* Probably we have a fragmented complex rule, which is not
                 * supported by this driver.
                 */
                dev_err(dev->dev, "ACL: number of bits set in RuleSet does not match calculated count\n");
                return -EINVAL;
        }

        /* loop over the contiguous entries and check for valid matching rules */
        for (i = start_idx; i <= end_idx; i++) {
                u8 *current_entry = &acles->entries[i].entry[0];

                if (!ksz9477_acl_is_valid_matching_rule(current_entry)) {
                        /* we have something linked without a valid matching
                         * rule. ACL table?
                         */
                        dev_err(dev->dev, "ACL: entry %d does not contain a valid matching rule\n",
                                i);
                        return -EINVAL;
                }

                if (i > start_idx) {
                        vale = current_entry[KSZ9477_ACL_PORT_ACCESS_E];
                        valf = current_entry[KSZ9477_ACL_PORT_ACCESS_F];
                        /* Following entry should have empty linkage list */
                        if (vale || valf) {
                                dev_err(dev->dev, "ACL: entry %d has non-empty RuleSet linkage\n",
                                        i);
                                return -EINVAL;
                        }
                }
        }

        return contiguous_count;
}

/**
 * ksz9477_acl_update_linkage - Update the RuleSet linkage for an ACL entry
 *                              after a move operation.
 *
 * @dev: Pointer to the ksz_device.
 * @entry:   Pointer to the ACL entry array.
 * @old_idx: The original index of the ACL entry before moving.
 * @new_idx: The new index of the ACL entry after moving.
 *
 * This function updates the RuleSet linkage bits for an ACL entry when
 * it's moved from one position to another in the ACL table. The RuleSet
 * linkage is represented by two 8-bit registers, which are combined
 * into a 16-bit value for easier manipulation. The linkage bits are shifted
 * based on the difference between the old and new index. If any bits are lost
 * during the shift operation, an error is returned.
 *
 * Note: Fragmentation within a RuleSet is not supported. Hence, entries must
 * be moved as complete blocks, maintaining the integrity of the RuleSet.
 *
 * Returns: 0 on success, or -EINVAL if any RuleSet linkage bits are lost
 * during the move.
 */
static int ksz9477_acl_update_linkage(struct ksz_device *dev, u8 *entry,
                                      u16 old_idx, u16 new_idx)
{
        unsigned int original_bit_count;
        unsigned long rule_linkage;
        u8 vale, valf, val0;
        int shift;

        val0 = entry[KSZ9477_ACL_PORT_ACCESS_0];
        vale = entry[KSZ9477_ACL_PORT_ACCESS_E];
        valf = entry[KSZ9477_ACL_PORT_ACCESS_F];

        /* Combine the two u8 values into one u16 for easier manipulation */
        rule_linkage = (vale << 8) | valf;
        original_bit_count = hweight16(rule_linkage);

        /* Even if HW is able to handle fragmented RuleSet, we don't support it.
         * RuleSet is filled only for the first entry of the set.
         */
        if (!rule_linkage)
                return 0;

        if (val0 != old_idx) {
                dev_err(dev->dev, "ACL: entry %d has unexpected ActionRule linkage: %d\n",
                        old_idx, val0);
                return -EINVAL;
        }

        val0 = new_idx;

        /* Calculate the number of positions to shift */
        shift = new_idx - old_idx;

        /* Shift the RuleSet */
        if (shift > 0)
                rule_linkage <<= shift;
        else
                rule_linkage >>= -shift;

        /* Check that no bits were lost in the process */
        if (original_bit_count != hweight16(rule_linkage)) {
                dev_err(dev->dev, "ACL RuleSet linkage bits lost during move\n");
                return -EINVAL;
        }

        entry[KSZ9477_ACL_PORT_ACCESS_0] = val0;

        /* Update the RuleSet bitfields in the entry */
        entry[KSZ9477_ACL_PORT_ACCESS_E] = (rule_linkage >> 8) & 0xFF;
        entry[KSZ9477_ACL_PORT_ACCESS_F] = rule_linkage & 0xFF;

        return 0;
}

/**
 * ksz9477_validate_and_get_src_count - Validate source and destination indices
 *                                      and determine the source entry count.
 * @dev: Pointer to the KSZ device structure.
 * @port: Port number on the KSZ device where the ACL entries reside.
 * @src_idx: Index of the starting ACL entry that needs to be validated.
 * @dst_idx: Index of the destination where the source entries are intended to
 *           be moved.
 * @src_count: Pointer to the variable that will hold the number of contiguous
 *           source entries if the validation passes.
 * @dst_count: Pointer to the variable that will hold the number of contiguous
 *           destination entries if the validation passes.
 *
 * This function performs validation on the source and destination indices
 * provided for ACL entries. It checks if the indices are within the valid
 * range, and if the source entries are contiguous. Additionally, the function
 * ensures that there's adequate space at the destination for the source entries
 * and that the destination index isn't in the middle of a RuleSet. If all
 * validations pass, the function returns the number of contiguous source and
 * destination entries.
 *
 * Return: 0 on success, otherwise returns a negative error code if any
 * validation check fails.
 */
static int ksz9477_validate_and_get_src_count(struct ksz_device *dev, int port,
                                              int src_idx, int dst_idx,
                                              int *src_count, int *dst_count)
{
        int ret;

        if (src_idx >= KSZ9477_ACL_MAX_ENTRIES ||
            dst_idx >= KSZ9477_ACL_MAX_ENTRIES) {
                dev_err(dev->dev, "ACL: invalid entry index\n");
                return -EINVAL;
        }

        /* Validate if the source entries are contiguous */
        ret = ksz9477_acl_get_cont_entr(dev, port, src_idx);
        if (ret < 0)
                return ret;
        *src_count = ret;

        if (!*src_count) {
                dev_err(dev->dev, "ACL: source entry is empty\n");
                return -EINVAL;
        }

        if (dst_idx + *src_count >= KSZ9477_ACL_MAX_ENTRIES) {
                dev_err(dev->dev, "ACL: Not enough space at the destination. Move operation will fail.\n");
                return -EINVAL;
        }

        /* Validate if the destination entry is empty or not in the middle of
         * a RuleSet.
         */
        ret = ksz9477_acl_get_cont_entr(dev, port, dst_idx);
        if (ret < 0)
                return ret;
        *dst_count = ret;

        return 0;
}

/**
 * ksz9477_move_entries_downwards - Move a range of ACL entries downwards in
 *                                  the list.
 * @dev: Pointer to the KSZ device structure.
 * @acles: Pointer to the structure encapsulating all the ACL entries.
 * @start_idx: Starting index of the entries to be relocated.
 * @num_entries_to_move: Number of consecutive entries to be relocated.
 * @end_idx: Destination index where the first entry should be situated post
 *           relocation.
 *
 * This function is responsible for rearranging a specific block of ACL entries
 * by shifting them downwards in the list based on the supplied source and
 * destination indices. It ensures that the linkage between the ACL entries is
 * maintained accurately after the relocation.
 *
 * Return: 0 on successful relocation of entries, otherwise returns a negative
 * error code.
 */
static int ksz9477_move_entries_downwards(struct ksz_device *dev,
                                          struct ksz9477_acl_entries *acles,
                                          u16 start_idx,
                                          u16 num_entries_to_move,
                                          u16 end_idx)
{
        struct ksz9477_acl_entry *e;
        int ret, i;

        for (i = start_idx; i < end_idx; i++) {
                e = &acles->entries[i];
                *e = acles->entries[i + num_entries_to_move];

                ret = ksz9477_acl_update_linkage(dev, &e->entry[0],
                                                 i + num_entries_to_move, i);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

/**
 * ksz9477_move_entries_upwards - Move a range of ACL entries upwards in the
 *                                list.
 * @dev: Pointer to the KSZ device structure.
 * @acles: Pointer to the structure holding all the ACL entries.
 * @start_idx: The starting index of the entries to be moved.
 * @num_entries_to_move: Number of contiguous entries to be moved.
 * @target_idx: The destination index where the first entry should be placed
 *              after moving.
 *
 * This function rearranges a chunk of ACL entries by moving them upwards
 * in the list based on the given source and destination indices. The reordering
 * process preserves the linkage between entries by updating it accordingly.
 *
 * Return: 0 if the entries were successfully moved, otherwise a negative error
 * code.
 */
static int ksz9477_move_entries_upwards(struct ksz_device *dev,
                                        struct ksz9477_acl_entries *acles,
                                        u16 start_idx, u16 num_entries_to_move,
                                        u16 target_idx)
{
        struct ksz9477_acl_entry *e;
        int ret, i, b;

        for (i = start_idx; i > target_idx; i--) {
                b = i + num_entries_to_move - 1;

                e = &acles->entries[b];
                *e = acles->entries[i - 1];

                ret = ksz9477_acl_update_linkage(dev, &e->entry[0], i - 1, b);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

/**
 * ksz9477_acl_move_entries - Move a block of contiguous ACL entries from a
 *                            source to a destination index.
 * @dev: Pointer to the KSZ9477 device structure.
 * @port: Port number.
 * @src_idx: Index of the starting source ACL entry.
 * @dst_idx: Index of the starting destination ACL entry.
 *
 * This function aims to move a block of contiguous ACL entries from the source
 * index to the destination index while ensuring the integrity and validity of
 * the ACL table.
 *
 * In case of any errors during the adjustments or copying, the function will
 * restore the ACL entries to their original state from the backup.
 *
 * Return: 0 if the move operation is successful. Returns -EINVAL for validation
 * errors or other error codes based on specific failure conditions.
 */
static int ksz9477_acl_move_entries(struct ksz_device *dev, int port,
                                    u16 src_idx, u16 dst_idx)
{
        struct ksz9477_acl_entry buffer[KSZ9477_ACL_MAX_ENTRIES];
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        int src_count, ret, dst_count;

        /* Nothing to do */
        if (src_idx == dst_idx)
                return 0;

        ret = ksz9477_validate_and_get_src_count(dev, port, src_idx, dst_idx,
                                                 &src_count, &dst_count);
        if (ret)
                return ret;

        /* In case dst_index is greater than src_index, we need to adjust the
         * destination index to account for the entries that will be moved
         * downwards and the size of the entry located at dst_idx.
         */
        if (dst_idx > src_idx)
                dst_idx = dst_idx + dst_count - src_count;

        /* Copy source block to buffer and update its linkage */
        for (int i = 0; i < src_count; i++) {
                buffer[i] = acles->entries[src_idx + i];
                ret = ksz9477_acl_update_linkage(dev, &buffer[i].entry[0],
                                                 src_idx + i, dst_idx + i);
                if (ret < 0)
                        return ret;
        }

        /* Adjust other entries and their linkage based on destination */
        if (dst_idx > src_idx) {
                ret = ksz9477_move_entries_downwards(dev, acles, src_idx,
                                                     src_count, dst_idx);
        } else {
                ret = ksz9477_move_entries_upwards(dev, acles, src_idx,
                                                   src_count, dst_idx);
        }
        if (ret < 0)
                return ret;

        /* Copy buffer to destination block */
        for (int i = 0; i < src_count; i++)
                acles->entries[dst_idx + i] = buffer[i];

        return 0;
}

/**
 * ksz9477_get_next_block_start - Identify the starting index of the next ACL
 *                                block.
 * @dev: Pointer to the device structure.
 * @port: The port number on which the ACL entries are being checked.
 * @start: The starting index from which the search begins.
 *
 * This function looks for the next valid ACL block starting from the provided
 * 'start' index and returns the beginning index of that block. If the block is
 * invalid or if it reaches the end of the ACL entries without finding another
 * block, it returns the maximum ACL entries count.
 *
 * Returns:
 *  - The starting index of the next valid ACL block.
 *  - KSZ9477_ACL_MAX_ENTRIES if no other valid blocks are found after 'start'.
 *  - A negative error code if an error occurs while checking.
 */
static int ksz9477_get_next_block_start(struct ksz_device *dev, int port,
                                        int start)
{
        int block_size;

        for (int i = start; i < KSZ9477_ACL_MAX_ENTRIES;) {
                block_size = ksz9477_acl_get_cont_entr(dev, port, i);
                if (block_size < 0 && block_size != -ENOTEMPTY)
                        return block_size;

                if (block_size > 0)
                        return i;

                i++;
        }
        return KSZ9477_ACL_MAX_ENTRIES;
}

/**
 * ksz9477_swap_acl_blocks - Swap two ACL blocks
 * @dev: Pointer to the device structure.
 * @port: The port number on which the ACL blocks are to be swapped.
 * @i: The starting index of the first ACL block.
 * @j: The starting index of the second ACL block.
 *
 * This function is used to swap two ACL blocks present at given indices. The
 * main purpose is to aid in the sorting and reordering of ACL blocks based on
 * certain criteria, e.g., priority. It checks the validity of the block at
 * index 'i', ensuring it's not an empty block, and then proceeds to swap it
 * with the block at index 'j'.
 *
 * Returns:
 *  - 0 on successful swapping of blocks.
 *  - -EINVAL if the block at index 'i' is empty.
 *  - A negative error code if any other error occurs during the swap.
 */
static int ksz9477_swap_acl_blocks(struct ksz_device *dev, int port, int i,
                                   int j)
{
        int ret, current_block_size;

        current_block_size = ksz9477_acl_get_cont_entr(dev, port, i);
        if (current_block_size < 0)
                return current_block_size;

        if (!current_block_size) {
                dev_err(dev->dev, "ACL: swapping empty entry %d\n", i);
                return -EINVAL;
        }

        ret = ksz9477_acl_move_entries(dev, port, i, j);
        if (ret)
                return ret;

        ret = ksz9477_acl_move_entries(dev, port, j - current_block_size, i);
        if (ret)
                return ret;

        return 0;
}

/**
 * ksz9477_sort_acl_entr_no_back - Sort ACL entries for a given port based on
 *                                 priority without backing up entries.
 * @dev: Pointer to the device structure.
 * @port: The port number whose ACL entries need to be sorted.
 *
 * This function sorts ACL entries of the specified port using a variant of the
 * bubble sort algorithm. It operates on blocks of ACL entries rather than
 * individual entries. Each block's starting point is identified and then
 * compared with subsequent blocks based on their priority. If the current
 * block has a lower priority than the subsequent block, the two blocks are
 * swapped.
 *
 * This is done in order to maintain an organized order of ACL entries based on
 * priority, ensuring efficient and predictable ACL rule application.
 *
 * Returns:
 *  - 0 on successful sorting of entries.
 *  - A negative error code if any issue arises during sorting, e.g.,
 *    if the function is unable to get the next block start.
 */
static int ksz9477_sort_acl_entr_no_back(struct ksz_device *dev, int port)
{
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        struct ksz9477_acl_entry *curr, *next;
        int i, j, ret;

        /* Bubble sort */
        for (i = 0; i < KSZ9477_ACL_MAX_ENTRIES;) {
                curr = &acles->entries[i];

                j = ksz9477_get_next_block_start(dev, port, i + 1);
                if (j < 0)
                        return j;

                while (j < KSZ9477_ACL_MAX_ENTRIES) {
                        next = &acles->entries[j];

                        if (curr->prio > next->prio) {
                                ret = ksz9477_swap_acl_blocks(dev, port, i, j);
                                if (ret)
                                        return ret;
                        }

                        j = ksz9477_get_next_block_start(dev, port, j + 1);
                        if (j < 0)
                                return j;
                }

                i = ksz9477_get_next_block_start(dev, port, i + 1);
                if (i < 0)
                        return i;
        }

        return 0;
}

/**
 * ksz9477_sort_acl_entries - Sort the ACL entries for a given port.
 * @dev: Pointer to the KSZ device.
 * @port: Port number.
 *
 * This function sorts the Access Control List (ACL) entries for a specified
 * port. Before sorting, a backup of the original entries is created. If the
 * sorting process fails, the function will log error messages displaying both
 * the original and attempted sorted entries, and then restore the original
 * entries from the backup.
 *
 * Return: 0 if the sorting succeeds, otherwise a negative error code.
 */
int ksz9477_sort_acl_entries(struct ksz_device *dev, int port)
{
        struct ksz9477_acl_entry backup[KSZ9477_ACL_MAX_ENTRIES];
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        int ret;

        /* create a backup of the ACL entries, if something goes wrong
         * we can restore the ACL entries.
         */
        memcpy(backup, acles->entries, sizeof(backup));

        ret = ksz9477_sort_acl_entr_no_back(dev, port);
        if (ret) {
                dev_err(dev->dev, "ACL: failed to sort entries for port %d\n",
                        port);
                dev_err(dev->dev, "ACL dump before sorting:\n");
                ksz9477_dump_acl(dev, backup);
                dev_err(dev->dev, "ACL dump after sorting:\n");
                ksz9477_dump_acl(dev, acles->entries);
                /* Restore the original entries */
                memcpy(acles->entries, backup, sizeof(backup));
        }

        return ret;
}

/**
 * ksz9477_acl_wait_ready - Waits for the ACL operation to complete on a given
 *                          port.
 * @dev: The ksz_device instance.
 * @port: The port number to wait for.
 *
 * This function checks if the ACL write or read operation is completed by
 * polling the specified register.
 *
 * Returns: 0 if the operation is successful, or a negative error code if an
 * error occurs.
 */
static int ksz9477_acl_wait_ready(struct ksz_device *dev, int port)
{
        unsigned int wr_mask = KSZ9477_ACL_WRITE_DONE | KSZ9477_ACL_READ_DONE;
        unsigned int val, reg;
        int ret;

        reg = dev->dev_ops->get_port_addr(port, KSZ9477_PORT_ACL_CTRL_0);

        ret = regmap_read_poll_timeout(dev->regmap[0], reg, val,
                                       (val & wr_mask) == wr_mask, 1000, 10000);
        if (ret)
                dev_err(dev->dev, "Failed to read/write ACL table\n");

        return ret;
}

/**
 * ksz9477_acl_entry_write - Writes an ACL entry to a given port at the
 *                           specified index.
 * @dev: The ksz_device instance.
 * @port: The port number to write the ACL entry to.
 * @entry: A pointer to the ACL entry data.
 * @idx: The index at which to write the ACL entry.
 *
 * This function writes the provided ACL entry to the specified port at the
 * given index.
 *
 * Returns: 0 if the operation is successful, or a negative error code if an
 * error occurs.
 */
static int ksz9477_acl_entry_write(struct ksz_device *dev, int port, u8 *entry,
                                   int idx)
{
        int ret, i;
        u8 val;

        for (i = 0; i < KSZ9477_ACL_ENTRY_SIZE; i++) {
                ret = ksz_pwrite8(dev, port, KSZ9477_PORT_ACL_0 + i, entry[i]);
                if (ret) {
                        dev_err(dev->dev, "Failed to write ACL entry %d\n", i);
                        return ret;
                }
        }

        /* write everything down */
        val = FIELD_PREP(KSZ9477_ACL_INDEX_M, idx) | KSZ9477_ACL_WRITE;
        ret = ksz_pwrite8(dev, port, KSZ9477_PORT_ACL_CTRL_0, val);
        if (ret)
                return ret;

        /* wait until everything is written  */
        return ksz9477_acl_wait_ready(dev, port);
}

/**
 * ksz9477_acl_port_enable - Enables ACL functionality on a given port.
 * @dev: The ksz_device instance.
 * @port: The port number on which to enable ACL functionality.
 *
 * This function enables ACL functionality on the specified port by configuring
 * the appropriate control registers. It returns 0 if the operation is
 * successful, or a negative error code if an error occurs.
 *
 * 0xn801 - KSZ9477S 5.2.8.2 Port Priority Control Register
 *        Bit 7 - Highest Priority
 *        Bit 6 - OR'ed Priority
 *        Bit 4 - MAC Address Priority Classification
 *        Bit 3 - VLAN Priority Classification
 *        Bit 2 - 802.1p Priority Classification
 *        Bit 1 - Diffserv Priority Classification
 *        Bit 0 - ACL Priority Classification
 *
 * Current driver implementation sets 802.1p priority classification by default.
 * In this function we add ACL priority classification with OR'ed priority.
 * According to testing, priority set by ACL will supersede the 802.1p priority.
 *
 * 0xn803 - KSZ9477S 5.2.8.4 Port Authentication Control Register
 *        Bit 2 - Access Control List (ACL) Enable
 *        Bits 1:0 - Authentication Mode
 *                00 = Reserved
 *                01 = Block Mode. Authentication is enabled. When ACL is
 *                     enabled, all traffic that misses the ACL rules is
 *                     blocked; otherwise ACL actions apply.
 *                10 = Pass Mode. Authentication is disabled. When ACL is
 *                     enabled, all traffic that misses the ACL rules is
 *                     forwarded; otherwise ACL actions apply.
 *                11 = Trap Mode. Authentication is enabled. All traffic is
 *                     forwarded to the host port. When ACL is enabled, all
 *                     traffic that misses the ACL rules is blocked; otherwise
 *                     ACL actions apply.
 *
 * We are using Pass Mode int this function.
 *
 * Returns: 0 if the operation is successful, or a negative error code if an
 * error occurs.
 */
static int ksz9477_acl_port_enable(struct ksz_device *dev, int port)
{
        int ret;

        ret = ksz_prmw8(dev, port, P_PRIO_CTRL, 0, PORT_ACL_PRIO_ENABLE |
                        PORT_OR_PRIO);
        if (ret)
                return ret;

        return ksz_pwrite8(dev, port, REG_PORT_MRI_AUTHEN_CTRL,
                           PORT_ACL_ENABLE |
                           FIELD_PREP(PORT_AUTHEN_MODE, PORT_AUTHEN_PASS));
}

/**
 * ksz9477_acl_port_disable - Disables ACL functionality on a given port.
 * @dev: The ksz_device instance.
 * @port: The port number on which to disable ACL functionality.
 *
 * This function disables ACL functionality on the specified port by writing a
 * value of 0 to the REG_PORT_MRI_AUTHEN_CTRL control register and remove
 * PORT_ACL_PRIO_ENABLE bit from P_PRIO_CTRL register.
 *
 * Returns: 0 if the operation is successful, or a negative error code if an
 * error occurs.
 */
static int ksz9477_acl_port_disable(struct ksz_device *dev, int port)
{
        int ret;

        ret = ksz_prmw8(dev, port, P_PRIO_CTRL, PORT_ACL_PRIO_ENABLE, 0);
        if (ret)
                return ret;

        return ksz_pwrite8(dev, port, REG_PORT_MRI_AUTHEN_CTRL, 0);
}

/**
 * ksz9477_acl_write_list - Write a list of ACL entries to a given port.
 * @dev: The ksz_device instance.
 * @port: The port number on which to write ACL entries.
 *
 * This function enables ACL functionality on the specified port, writes a list
 * of ACL entries to the port, and disables ACL functionality if there are no
 * entries.
 *
 * Returns: 0 if the operation is successful, or a negative error code if an
 * error occurs.
 */
int ksz9477_acl_write_list(struct ksz_device *dev, int port)
{
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        int ret, i;

        /* ACL should be enabled before writing entries */
        ret = ksz9477_acl_port_enable(dev, port);
        if (ret)
                return ret;

        /* write all entries */
        for (i = 0; i < ARRAY_SIZE(acles->entries); i++) {
                u8 *entry = acles->entries[i].entry;

                /* Check if entry was removed and should be zeroed.
                 * If last fields of the entry are not zero, it means
                 * it is removed locally but currently not synced with the HW.
                 * So, we will write it down to the HW to remove it.
                 */
                if (i >= acles->entries_count &&
                    entry[KSZ9477_ACL_PORT_ACCESS_10] == 0 &&
                    entry[KSZ9477_ACL_PORT_ACCESS_11] == 0)
                        continue;

                ret = ksz9477_acl_entry_write(dev, port, entry, i);
                if (ret)
                        return ret;

                /* now removed entry is clean on HW side, so it can
                 * in the cache too
                 */
                if (i >= acles->entries_count &&
                    entry[KSZ9477_ACL_PORT_ACCESS_10] != 0 &&
                    entry[KSZ9477_ACL_PORT_ACCESS_11] != 0) {
                        entry[KSZ9477_ACL_PORT_ACCESS_10] = 0;
                        entry[KSZ9477_ACL_PORT_ACCESS_11] = 0;
                }
        }

        if (!acles->entries_count)
                return ksz9477_acl_port_disable(dev, port);

        return 0;
}

/**
 * ksz9477_acl_remove_entries - Remove ACL entries with a given cookie from a
 *                              specified ksz9477_acl_entries structure.
 * @dev: The ksz_device instance.
 * @port: The port number on which to remove ACL entries.
 * @acles: The ksz9477_acl_entries instance.
 * @cookie: The cookie value to match for entry removal.
 *
 * This function iterates through the entries array, removing any entries with
 * a matching cookie value. The remaining entries are then shifted down to fill
 * the gap.
 */
void ksz9477_acl_remove_entries(struct ksz_device *dev, int port,
                                struct ksz9477_acl_entries *acles,
                                unsigned long cookie)
{
        int entries_count = acles->entries_count;
        int ret, i, src_count;
        int src_idx = -1;

        if (!entries_count)
                return;

        /* Search for the first position with the cookie */
        for (i = 0; i < entries_count; i++) {
                if (acles->entries[i].cookie == cookie) {
                        src_idx = i;
                        break;
                }
        }

        /* No entries with the matching cookie found */
        if (src_idx == -1)
                return;

        /* Get the size of the cookie entry. We may have complex entries. */
        src_count = ksz9477_acl_get_cont_entr(dev, port, src_idx);
        if (src_count <= 0)
                return;

        /* Move all entries down to overwrite removed entry with the cookie */
        ret = ksz9477_move_entries_downwards(dev, acles, src_idx,
                                             src_count,
                                             entries_count - src_count);
        if (ret) {
                dev_err(dev->dev, "Failed to move ACL entries down\n");
                return;
        }

        /* Overwrite new empty places at the end of the list with zeros to make
         * sure not unexpected things will happen or no unexplored quirks will
         * come out.
         */
        for (i = entries_count - src_count; i < entries_count; i++) {
                struct ksz9477_acl_entry *entry = &acles->entries[i];

                memset(entry, 0, sizeof(*entry));

                /* Set all access bits to be able to write zeroed entry to HW */
                entry->entry[KSZ9477_ACL_PORT_ACCESS_10] = 0xff;
                entry->entry[KSZ9477_ACL_PORT_ACCESS_11] = 0xff;
        }

        /* Adjust the total entries count */
        acles->entries_count -= src_count;
}

/**
 * ksz9477_port_acl_init - Initialize the ACL for a specified port on a ksz
 *                         device.
 * @dev: The ksz_device instance.
 * @port: The port number to initialize the ACL for.
 *
 * This function allocates memory for an acl structure, associates it with the
 * specified port, and initializes the ACL entries to a default state. The
 * entries are then written using the ksz9477_acl_write_list function, ensuring
 * the ACL has a predictable initial hardware state.
 *
 * Returns: 0 on success, or an error code on failure.
 */
int ksz9477_port_acl_init(struct ksz_device *dev, int port)
{
        struct ksz9477_acl_entries *acles;
        struct ksz9477_acl_priv *acl;
        int ret, i;

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

        dev->ports[port].acl_priv = acl;

        acles = &acl->acles;
        /* write all entries */
        for (i = 0; i < ARRAY_SIZE(acles->entries); i++) {
                u8 *entry = acles->entries[i].entry;

                /* Set all access bits to be able to write zeroed
                 * entry
                 */
                entry[KSZ9477_ACL_PORT_ACCESS_10] = 0xff;
                entry[KSZ9477_ACL_PORT_ACCESS_11] = 0xff;
        }

        ret = ksz9477_acl_write_list(dev, port);
        if (ret)
                goto free_acl;

        return 0;

free_acl:
        kfree(dev->ports[port].acl_priv);
        dev->ports[port].acl_priv = NULL;

        return ret;
}

/**
 * ksz9477_port_acl_free - Free the ACL resources for a specified port on a ksz
 *                         device.
 * @dev: The ksz_device instance.
 * @port: The port number to initialize the ACL for.
 *
 * This disables the ACL for the specified port and frees the associated memory,
 */
void ksz9477_port_acl_free(struct ksz_device *dev, int port)
{
        if (!dev->ports[port].acl_priv)
                return;

        ksz9477_acl_port_disable(dev, port);

        kfree(dev->ports[port].acl_priv);
        dev->ports[port].acl_priv = NULL;
}

/**
 * ksz9477_acl_set_reg - Set entry[16] and entry[17] depending on the updated
 *                         entry[]
 * @entry: An array containing the entries
 * @reg: The register of the entry that needs to be updated
 * @value: The value to be assigned to the updated entry
 *
 * This function updates the entry[] array based on the provided register and
 * value. It also sets entry[0x10] and entry[0x11] according to the ACL byte
 * enable rules.
 *
 * 0x10 - Byte Enable [15:8]
 *
 * Each bit enables accessing one of the ACL bytes when a read or write is
 * initiated by writing to the Port ACL Byte Enable LSB Register.
 * Bit 0 applies to the Port ACL Access 7 Register
 * Bit 1 applies to the Port ACL Access 6 Register, etc.
 * Bit 7 applies to the Port ACL Access 0 Register
 * 1 = Byte is selected for read/write
 * 0 = Byte is not selected
 *
 * 0x11 - Byte Enable [7:0]
 *
 * Each bit enables accessing one of the ACL bytes when a read or write is
 * initiated by writing to the Port ACL Byte Enable LSB Register.
 * Bit 0 applies to the Port ACL Access F Register
 * Bit 1 applies to the Port ACL Access E Register, etc.
 * Bit 7 applies to the Port ACL Access 8 Register
 * 1 = Byte is selected for read/write
 * 0 = Byte is not selected
 */
static void ksz9477_acl_set_reg(u8 *entry, enum ksz9477_acl_port_access reg,
                                u8 value)
{
        if (reg >= KSZ9477_ACL_PORT_ACCESS_0 &&
            reg <= KSZ9477_ACL_PORT_ACCESS_7) {
                entry[KSZ9477_ACL_PORT_ACCESS_10] |=
                                BIT(KSZ9477_ACL_PORT_ACCESS_7 - reg);
        } else if (reg >= KSZ9477_ACL_PORT_ACCESS_8 &&
                   reg <= KSZ9477_ACL_PORT_ACCESS_F) {
                entry[KSZ9477_ACL_PORT_ACCESS_11] |=
                        BIT(KSZ9477_ACL_PORT_ACCESS_F - reg);
        } else {
                WARN_ON(1);
                return;
        }

        entry[reg] = value;
}

/**
 * ksz9477_acl_matching_rule_cfg_l2 - Configure an ACL filtering entry to match
 *                                    L2 types of Ethernet frames
 * @entry: Pointer to ACL entry buffer
 * @ethertype: Ethertype value
 * @eth_addr: Pointer to Ethernet address
 * @is_src: If true, match the source MAC address; if false, match the
 *          destination MAC address
 *
 * This function configures an Access Control List (ACL) filtering
 * entry to match Layer 2 types of Ethernet frames based on the provided
 * ethertype and Ethernet address. Additionally, it can match either the source
 * or destination MAC address depending on the value of the is_src parameter.
 *
 * Register Descriptions for MD = 01 and ENB != 00 (Layer 2 MAC header
 * filtering)
 *
 * 0x01 - Mode and Enable
 *        Bits 5:4 - MD (Mode)
 *                01 = Layer 2 MAC header or counter filtering
 *        Bits 3:2 - ENB (Enable)
 *                01 = Comparison is performed only on the TYPE value
 *                10 = Comparison is performed only on the MAC Address value
 *                11 = Both the MAC Address and TYPE are tested
 *        Bit  1   - S/D (Source / Destination)
 *                0 = Destination address
 *                1 = Source address
 *        Bit  0   - EQ (Equal / Not Equal)
 *                0 = Not Equal produces true result
 *                1 = Equal produces true result
 *
 * 0x02-0x07 - MAC Address
 *        0x02 - MAC Address [47:40]
 *        0x03 - MAC Address [39:32]
 *        0x04 - MAC Address [31:24]
 *        0x05 - MAC Address [23:16]
 *        0x06 - MAC Address [15:8]
 *        0x07 - MAC Address [7:0]
 *
 * 0x08-0x09 - EtherType
 *        0x08 - EtherType [15:8]
 *        0x09 - EtherType [7:0]
 */
static void ksz9477_acl_matching_rule_cfg_l2(u8 *entry, u16 ethertype,
                                             u8 *eth_addr, bool is_src)
{
        u8 enb = 0;
        u8 val;

        if (ethertype)
                enb |= KSZ9477_ACL_ENB_L2_TYPE;
        if (eth_addr)
                enb |= KSZ9477_ACL_ENB_L2_MAC;

        val = FIELD_PREP(KSZ9477_ACL_MD_MASK, KSZ9477_ACL_MD_L2_MAC) |
              FIELD_PREP(KSZ9477_ACL_ENB_MASK, enb) |
              FIELD_PREP(KSZ9477_ACL_SD_SRC, is_src) | KSZ9477_ACL_EQ_EQUAL;
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_1, val);

        if (eth_addr) {
                int i;

                for (i = 0; i < ETH_ALEN; i++) {
                        ksz9477_acl_set_reg(entry,
                                            KSZ9477_ACL_PORT_ACCESS_2 + i,
                                            eth_addr[i]);
                }
        }

        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_8, ethertype >> 8);
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_9, ethertype & 0xff);
}

/**
 * ksz9477_acl_action_rule_cfg - Set action for an ACL entry
 * @entry: Pointer to the ACL entry
 * @force_prio: If true, force the priority value
 * @prio_val: Priority value
 *
 * This function sets the action for the specified ACL entry. It prepares
 * the priority mode and traffic class values and updates the entry's
 * action registers accordingly. Currently, there is no port or VLAN PCP
 * remapping.
 *
 * ACL Action Rule Parameters for Non-Count Modes (MD ≠ 01 or ENB ≠ 00)
 *
 * 0x0A - PM, P, RPE, RP[2:1]
 *        Bits 7:6 - PM[1:0] - Priority Mode
 *              00 = ACL does not specify the packet priority. Priority is
 *                   determined by standard QoS functions.
 *              01 = Change packet priority to P[2:0] if it is greater than QoS
 *                   result.
 *              10 = Change packet priority to P[2:0] if it is smaller than the
 *                   QoS result.
 *              11 = Always change packet priority to P[2:0].
 *        Bits 5:3 - P[2:0] - Priority value
 *        Bit  2   - RPE - Remark Priority Enable
 *        Bits 1:0 - RP[2:1] - Remarked Priority value (bits 2:1)
 *              0 = Disable priority remarking
 *              1 = Enable priority remarking. VLAN tag priority (PCP) bits are
 *                  replaced by RP[2:0].
 *
 * 0x0B - RP[0], MM
 *        Bit  7   - RP[0] - Remarked Priority value (bit 0)
 *        Bits 6:5 - MM[1:0] - Map Mode
 *              00 = No forwarding remapping
 *              01 = The forwarding map in FORWARD is OR'ed with the forwarding
 *                   map from the Address Lookup Table.
 *              10 = The forwarding map in FORWARD is AND'ed with the forwarding
 *                   map from the Address Lookup Table.
 *              11 = The forwarding map in FORWARD replaces the forwarding map
 *                   from the Address Lookup Table.
 * 0x0D - FORWARD[n:0]
 *       Bits 7:0 - FORWARD[n:0] - Forwarding map. Bit 0 = port 1,
 *                  bit 1 = port 2, etc.
 *              1 = enable forwarding to this port
 *              0 = do not forward to this port
 */
void ksz9477_acl_action_rule_cfg(u8 *entry, bool force_prio, u8 prio_val)
{
        u8 prio_mode, val;

        if (force_prio)
                prio_mode = KSZ9477_ACL_PM_REPLACE;
        else
                prio_mode = KSZ9477_ACL_PM_DISABLE;

        val = FIELD_PREP(KSZ9477_ACL_PM_M, prio_mode) |
              FIELD_PREP(KSZ9477_ACL_P_M, prio_val);
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_A, val);

        /* no port or VLAN PCP remapping for now */
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_B, 0);
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_D, 0);
}

/**
 * ksz9477_acl_processing_rule_set_action - Set the action for the processing
 *                                          rule set.
 * @entry: Pointer to the ACL entry
 * @action_idx: Index of the action to be applied
 *
 * This function sets the action for the processing rule set by updating the
 * appropriate register in the entry. There can be only one action per
 * processing rule.
 *
 * Access Control List (ACL) Processing Rule Registers:
 *
 * 0x00 - First Rule Number (FRN)
 *        Bits 3:0 - First Rule Number. Pointer to an Action rule entry.
 */
void ksz9477_acl_processing_rule_set_action(u8 *entry, u8 action_idx)
{
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_0, action_idx);
}

/**
 * ksz9477_acl_processing_rule_add_match - Add a matching rule to the rule set
 * @entry: Pointer to the ACL entry
 * @match_idx: Index of the matching rule to be added
 *
 * This function adds a matching rule to the rule set by updating the
 * appropriate bits in the entry's rule set registers.
 *
 * Access Control List (ACL) Processing Rule Registers:
 *
 * 0x0E - RuleSet [15:8]
 *        Bits 7:0 - RuleSet [15:8] Specifies a set of one or more Matching rule
 *        entries. RuleSet has one bit for each of the 16 Matching rule entries.
 *        If multiple Matching rules are selected, then all conditions will be
 *        AND'ed to produce a final match result.
 *              0 = Matching rule not selected
 *              1 = Matching rule selected
 *
 * 0x0F - RuleSet [7:0]
 *        Bits 7:0 - RuleSet [7:0]
 */
static void ksz9477_acl_processing_rule_add_match(u8 *entry, u8 match_idx)
{
        u8 vale = entry[KSZ9477_ACL_PORT_ACCESS_E];
        u8 valf = entry[KSZ9477_ACL_PORT_ACCESS_F];

        if (match_idx < 8)
                valf |= BIT(match_idx);
        else
                vale |= BIT(match_idx - 8);

        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_E, vale);
        ksz9477_acl_set_reg(entry, KSZ9477_ACL_PORT_ACCESS_F, valf);
}

/**
 * ksz9477_acl_get_init_entry - Get a new uninitialized entry for a specified
 *                              port on a ksz_device.
 * @dev: The ksz_device instance.
 * @port: The port number to get the uninitialized entry for.
 * @cookie: The cookie to associate with the entry.
 * @prio: The priority to associate with the entry.
 *
 * This function retrieves the next available ACL entry for the specified port,
 * clears all access flags, and associates it with the current cookie.
 *
 * Returns: A pointer to the new uninitialized ACL entry.
 */
static struct ksz9477_acl_entry *
ksz9477_acl_get_init_entry(struct ksz_device *dev, int port,
                           unsigned long cookie, u32 prio)
{
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        struct ksz9477_acl_entry *entry;

        entry = &acles->entries[acles->entries_count];
        entry->cookie = cookie;
        entry->prio = prio;

        /* clear all access flags */
        entry->entry[KSZ9477_ACL_PORT_ACCESS_10] = 0;
        entry->entry[KSZ9477_ACL_PORT_ACCESS_11] = 0;

        return entry;
}

/**
 * ksz9477_acl_match_process_l2 - Configure Layer 2 ACL matching rules and
 *                                processing rules.
 * @dev: Pointer to the ksz_device.
 * @port: Port number.
 * @ethtype: Ethernet type.
 * @src_mac: Source MAC address.
 * @dst_mac: Destination MAC address.
 * @cookie: The cookie to associate with the entry.
 * @prio: The priority of the entry.
 *
 * This function sets up matching and processing rules for Layer 2 ACLs.
 * It takes into account that only one MAC per entry is supported.
 */
void ksz9477_acl_match_process_l2(struct ksz_device *dev, int port,
                                  u16 ethtype, u8 *src_mac, u8 *dst_mac,
                                  unsigned long cookie, u32 prio)
{
        struct ksz9477_acl_priv *acl = dev->ports[port].acl_priv;
        struct ksz9477_acl_entries *acles = &acl->acles;
        struct ksz9477_acl_entry *entry;

        entry = ksz9477_acl_get_init_entry(dev, port, cookie, prio);

        /* ACL supports only one MAC per entry */
        if (src_mac && dst_mac) {
                ksz9477_acl_matching_rule_cfg_l2(entry->entry, ethtype, src_mac,
                                                 true);

                /* Add both match entries to first processing rule */
                ksz9477_acl_processing_rule_add_match(entry->entry,
                                                      acles->entries_count);
                acles->entries_count++;
                ksz9477_acl_processing_rule_add_match(entry->entry,
                                                      acles->entries_count);

                entry = ksz9477_acl_get_init_entry(dev, port, cookie, prio);
                ksz9477_acl_matching_rule_cfg_l2(entry->entry, 0, dst_mac,
                                                 false);
                acles->entries_count++;
        } else {
                u8 *mac = src_mac ? src_mac : dst_mac;
                bool is_src = src_mac ? true : false;

                ksz9477_acl_matching_rule_cfg_l2(entry->entry, ethtype, mac,
                                                 is_src);
                ksz9477_acl_processing_rule_add_match(entry->entry,
                                                      acles->entries_count);
                acles->entries_count++;
        }
}