// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2018-2019, Vladimir Oltean <olteanv@gmail.com>
 */
#include "sja1105.h"

#define SJA1105_SIZE_DYN_CMD					4

#define SJA1105ET_SIZE_MAC_CONFIG_DYN_ENTRY			\
	SJA1105_SIZE_DYN_CMD

#define SJA1105ET_SIZE_L2_LOOKUP_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + SJA1105ET_SIZE_L2_LOOKUP_ENTRY)

#define SJA1105PQRS_SIZE_L2_LOOKUP_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY)

#define SJA1105_SIZE_VLAN_LOOKUP_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + 4 + SJA1105_SIZE_VLAN_LOOKUP_ENTRY)

#define SJA1105_SIZE_L2_FORWARDING_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + SJA1105_SIZE_L2_FORWARDING_ENTRY)

#define SJA1105ET_SIZE_MAC_CONFIG_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + SJA1105ET_SIZE_MAC_CONFIG_DYN_ENTRY)

#define SJA1105PQRS_SIZE_MAC_CONFIG_DYN_CMD			\
	(SJA1105_SIZE_DYN_CMD + SJA1105PQRS_SIZE_MAC_CONFIG_ENTRY)

#define SJA1105ET_SIZE_L2_LOOKUP_PARAMS_DYN_CMD			\
	SJA1105_SIZE_DYN_CMD

#define SJA1105ET_SIZE_GENERAL_PARAMS_DYN_CMD			\
	SJA1105_SIZE_DYN_CMD

#define SJA1105_MAX_DYN_CMD_SIZE				\
	SJA1105PQRS_SIZE_MAC_CONFIG_DYN_CMD

static void
sja1105pqrs_l2_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				  enum packing_op op)
{
	u8 *p = buf + SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY;
	const int size = SJA1105_SIZE_DYN_CMD;

	sja1105_packing(p, &cmd->valid,    31, 31, size, op);
	sja1105_packing(p, &cmd->rdwrset,  30, 30, size, op);
	sja1105_packing(p, &cmd->errors,   29, 29, size, op);
	sja1105_packing(p, &cmd->valident, 27, 27, size, op);
	/* Hack - The hardware takes the 'index' field within
	 * struct sja1105_l2_lookup_entry as the index on which this command
	 * will operate. However it will ignore everything else, so 'index'
	 * is logically part of command but physically part of entry.
	 * Populate the 'index' entry field from within the command callback,
	 * such that our API doesn't need to ask for a full-blown entry
	 * structure when e.g. a delete is requested.
	 */
	sja1105_packing(buf, &cmd->index, 29, 20,
			SJA1105PQRS_SIZE_L2_LOOKUP_ENTRY, op);
	/* TODO hostcmd */
}

static void
sja1105et_l2_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				enum packing_op op)
{
	u8 *p = buf + SJA1105ET_SIZE_L2_LOOKUP_ENTRY;
	const int size = SJA1105_SIZE_DYN_CMD;

	sja1105_packing(p, &cmd->valid,    31, 31, size, op);
	sja1105_packing(p, &cmd->rdwrset,  30, 30, size, op);
	sja1105_packing(p, &cmd->errors,   29, 29, size, op);
	sja1105_packing(p, &cmd->valident, 27, 27, size, op);
	/* Hack - see comments above. */
	sja1105_packing(buf, &cmd->index, 29, 20,
			SJA1105ET_SIZE_L2_LOOKUP_ENTRY, op);
}

static void
sja1105et_mgmt_route_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				 enum packing_op op)
{
	u8 *p = buf + SJA1105ET_SIZE_L2_LOOKUP_ENTRY;
	u64 mgmtroute = 1;

	sja1105et_l2_lookup_cmd_packing(buf, cmd, op);
	if (op == PACK)
		sja1105_pack(p, &mgmtroute, 26, 26, SJA1105_SIZE_DYN_CMD);
}

static size_t sja1105et_mgmt_route_entry_packing(void *buf, void *entry_ptr,
						 enum packing_op op)
{
	struct sja1105_mgmt_entry *entry = entry_ptr;
	const size_t size = SJA1105ET_SIZE_L2_LOOKUP_ENTRY;

	/* UM10944: To specify if a PTP egress timestamp shall be captured on
	 * each port upon transmission of the frame, the LSB of VLANID in the
	 * ENTRY field provided by the host must be set.
	 * Bit 1 of VLANID then specifies the register where the timestamp for
	 * this port is stored in.
	 */
	sja1105_packing(buf, &entry->tsreg,     85, 85, size, op);
	sja1105_packing(buf, &entry->takets,    84, 84, size, op);
	sja1105_packing(buf, &entry->macaddr,   83, 36, size, op);
	sja1105_packing(buf, &entry->destports, 35, 31, size, op);
	sja1105_packing(buf, &entry->enfport,   30, 30, size, op);
	return size;
}

/* In E/T, entry is at addresses 0x27-0x28. There is a 4 byte gap at 0x29,
 * and command is at 0x2a. Similarly in P/Q/R/S there is a 1 register gap
 * between entry (0x2d, 0x2e) and command (0x30).
 */
static void
sja1105_vlan_lookup_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				enum packing_op op)
{
	u8 *p = buf + SJA1105_SIZE_VLAN_LOOKUP_ENTRY + 4;
	const int size = SJA1105_SIZE_DYN_CMD;

	sja1105_packing(p, &cmd->valid,    31, 31, size, op);
	sja1105_packing(p, &cmd->rdwrset,  30, 30, size, op);
	sja1105_packing(p, &cmd->valident, 27, 27, size, op);
	/* Hack - see comments above, applied for 'vlanid' field of
	 * struct sja1105_vlan_lookup_entry.
	 */
	sja1105_packing(buf, &cmd->index, 38, 27,
			SJA1105_SIZE_VLAN_LOOKUP_ENTRY, op);
}

static void
sja1105_l2_forwarding_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				  enum packing_op op)
{
	u8 *p = buf + SJA1105_SIZE_L2_FORWARDING_ENTRY;
	const int size = SJA1105_SIZE_DYN_CMD;

	sja1105_packing(p, &cmd->valid,   31, 31, size, op);
	sja1105_packing(p, &cmd->errors,  30, 30, size, op);
	sja1105_packing(p, &cmd->rdwrset, 29, 29, size, op);
	sja1105_packing(p, &cmd->index,    4,  0, size, op);
}

static void
sja1105et_mac_config_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				 enum packing_op op)
{
	const int size = SJA1105_SIZE_DYN_CMD;
	/* Yup, user manual definitions are reversed */
	u8 *reg1 = buf + 4;

	sja1105_packing(reg1, &cmd->valid, 31, 31, size, op);
	sja1105_packing(reg1, &cmd->index, 26, 24, size, op);
}

static size_t sja1105et_mac_config_entry_packing(void *buf, void *entry_ptr,
						 enum packing_op op)
{
	const int size = SJA1105ET_SIZE_MAC_CONFIG_DYN_ENTRY;
	struct sja1105_mac_config_entry *entry = entry_ptr;
	/* Yup, user manual definitions are reversed */
	u8 *reg1 = buf + 4;
	u8 *reg2 = buf;

	sja1105_packing(reg1, &entry->speed,     30, 29, size, op);
	sja1105_packing(reg1, &entry->drpdtag,   23, 23, size, op);
	sja1105_packing(reg1, &entry->drpuntag,  22, 22, size, op);
	sja1105_packing(reg1, &entry->retag,     21, 21, size, op);
	sja1105_packing(reg1, &entry->dyn_learn, 20, 20, size, op);
	sja1105_packing(reg1, &entry->egress,    19, 19, size, op);
	sja1105_packing(reg1, &entry->ingress,   18, 18, size, op);
	sja1105_packing(reg1, &entry->ing_mirr,  17, 17, size, op);
	sja1105_packing(reg1, &entry->egr_mirr,  16, 16, size, op);
	sja1105_packing(reg1, &entry->vlanprio,  14, 12, size, op);
	sja1105_packing(reg1, &entry->vlanid,    11,  0, size, op);
	sja1105_packing(reg2, &entry->tp_delin,  31, 16, size, op);
	sja1105_packing(reg2, &entry->tp_delout, 15,  0, size, op);
	/* MAC configuration table entries which can't be reconfigured:
	 * top, base, enabled, ifg, maxage, drpnona664
	 */
	/* Bogus return value, not used anywhere */
	return 0;
}

static void
sja1105pqrs_mac_config_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				   enum packing_op op)
{
	const int size = SJA1105ET_SIZE_MAC_CONFIG_DYN_ENTRY;
	u8 *p = buf + SJA1105PQRS_SIZE_MAC_CONFIG_ENTRY;

	sja1105_packing(p, &cmd->valid,   31, 31, size, op);
	sja1105_packing(p, &cmd->errors,  30, 30, size, op);
	sja1105_packing(p, &cmd->rdwrset, 29, 29, size, op);
	sja1105_packing(p, &cmd->index,    2,  0, size, op);
}

static void
sja1105et_l2_lookup_params_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				       enum packing_op op)
{
	sja1105_packing(buf, &cmd->valid, 31, 31,
			SJA1105ET_SIZE_L2_LOOKUP_PARAMS_DYN_CMD, op);
}

static size_t
sja1105et_l2_lookup_params_entry_packing(void *buf, void *entry_ptr,
					 enum packing_op op)
{
	struct sja1105_l2_lookup_params_entry *entry = entry_ptr;

	sja1105_packing(buf, &entry->poly, 7, 0,
			SJA1105ET_SIZE_L2_LOOKUP_PARAMS_DYN_CMD, op);
	/* Bogus return value, not used anywhere */
	return 0;
}

static void
sja1105et_general_params_cmd_packing(void *buf, struct sja1105_dyn_cmd *cmd,
				     enum packing_op op)
{
	const int size = SJA1105ET_SIZE_GENERAL_PARAMS_DYN_CMD;

	sja1105_packing(buf, &cmd->valid,  31, 31, size, op);
	sja1105_packing(buf, &cmd->errors, 30, 30, size, op);
}

static size_t
sja1105et_general_params_entry_packing(void *buf, void *entry_ptr,
				       enum packing_op op)
{
	struct sja1105_general_params_entry *entry = entry_ptr;
	const int size = SJA1105ET_SIZE_GENERAL_PARAMS_DYN_CMD;

	sja1105_packing(buf, &entry->mirr_port, 2, 0, size, op);
	/* Bogus return value, not used anywhere */
	return 0;
}

#define OP_READ		BIT(0)
#define OP_WRITE	BIT(1)
#define OP_DEL		BIT(2)

/* SJA1105E/T: First generation */
struct sja1105_dynamic_table_ops sja1105et_dyn_ops[BLK_IDX_MAX_DYN] = {
	[BLK_IDX_L2_LOOKUP] = {
		.entry_packing = sja1105et_l2_lookup_entry_packing,
		.cmd_packing = sja1105et_l2_lookup_cmd_packing,
		.access = (OP_READ | OP_WRITE | OP_DEL),
		.max_entry_count = SJA1105_MAX_L2_LOOKUP_COUNT,
		.packed_size = SJA1105ET_SIZE_L2_LOOKUP_DYN_CMD,
		.addr = 0x20,
	},
	[BLK_IDX_MGMT_ROUTE] = {
		.entry_packing = sja1105et_mgmt_route_entry_packing,
		.cmd_packing = sja1105et_mgmt_route_cmd_packing,
		.access = (OP_READ | OP_WRITE),
		.max_entry_count = SJA1105_NUM_PORTS,
		.packed_size = SJA1105ET_SIZE_L2_LOOKUP_DYN_CMD,
		.addr = 0x20,
	},
	[BLK_IDX_L2_POLICING] = {0},
	[BLK_IDX_VLAN_LOOKUP] = {
		.entry_packing = sja1105_vlan_lookup_entry_packing,
		.cmd_packing = sja1105_vlan_lookup_cmd_packing,
		.access = (OP_WRITE | OP_DEL),
		.max_entry_count = SJA1105_MAX_VLAN_LOOKUP_COUNT,
		.packed_size = SJA1105_SIZE_VLAN_LOOKUP_DYN_CMD,
		.addr = 0x27,
	},
	[BLK_IDX_L2_FORWARDING] = {
		.entry_packing = sja1105_l2_forwarding_entry_packing,
		.cmd_packing = sja1105_l2_forwarding_cmd_packing,
		.max_entry_count = SJA1105_MAX_L2_FORWARDING_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105_SIZE_L2_FORWARDING_DYN_CMD,
		.addr = 0x24,
	},
	[BLK_IDX_MAC_CONFIG] = {
		.entry_packing = sja1105et_mac_config_entry_packing,
		.cmd_packing = sja1105et_mac_config_cmd_packing,
		.max_entry_count = SJA1105_MAX_MAC_CONFIG_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105ET_SIZE_MAC_CONFIG_DYN_CMD,
		.addr = 0x36,
	},
	[BLK_IDX_L2_LOOKUP_PARAMS] = {
		.entry_packing = sja1105et_l2_lookup_params_entry_packing,
		.cmd_packing = sja1105et_l2_lookup_params_cmd_packing,
		.max_entry_count = SJA1105_MAX_L2_LOOKUP_PARAMS_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105ET_SIZE_L2_LOOKUP_PARAMS_DYN_CMD,
		.addr = 0x38,
	},
	[BLK_IDX_L2_FORWARDING_PARAMS] = {0},
	[BLK_IDX_GENERAL_PARAMS] = {
		.entry_packing = sja1105et_general_params_entry_packing,
		.cmd_packing = sja1105et_general_params_cmd_packing,
		.max_entry_count = SJA1105_MAX_GENERAL_PARAMS_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105ET_SIZE_GENERAL_PARAMS_DYN_CMD,
		.addr = 0x34,
	},
	[BLK_IDX_XMII_PARAMS] = {0},
};

/* SJA1105P/Q/R/S: Second generation: TODO */
struct sja1105_dynamic_table_ops sja1105pqrs_dyn_ops[BLK_IDX_MAX_DYN] = {
	[BLK_IDX_L2_LOOKUP] = {
		.entry_packing = sja1105pqrs_l2_lookup_entry_packing,
		.cmd_packing = sja1105pqrs_l2_lookup_cmd_packing,
		.access = (OP_READ | OP_WRITE | OP_DEL),
		.max_entry_count = SJA1105_MAX_L2_LOOKUP_COUNT,
		.packed_size = SJA1105ET_SIZE_L2_LOOKUP_DYN_CMD,
		.addr = 0x24,
	},
	[BLK_IDX_L2_POLICING] = {0},
	[BLK_IDX_VLAN_LOOKUP] = {
		.entry_packing = sja1105_vlan_lookup_entry_packing,
		.cmd_packing = sja1105_vlan_lookup_cmd_packing,
		.access = (OP_READ | OP_WRITE | OP_DEL),
		.max_entry_count = SJA1105_MAX_VLAN_LOOKUP_COUNT,
		.packed_size = SJA1105_SIZE_VLAN_LOOKUP_DYN_CMD,
		.addr = 0x2D,
	},
	[BLK_IDX_L2_FORWARDING] = {
		.entry_packing = sja1105_l2_forwarding_entry_packing,
		.cmd_packing = sja1105_l2_forwarding_cmd_packing,
		.max_entry_count = SJA1105_MAX_L2_FORWARDING_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105_SIZE_L2_FORWARDING_DYN_CMD,
		.addr = 0x2A,
	},
	[BLK_IDX_MAC_CONFIG] = {
		.entry_packing = sja1105pqrs_mac_config_entry_packing,
		.cmd_packing = sja1105pqrs_mac_config_cmd_packing,
		.max_entry_count = SJA1105_MAX_MAC_CONFIG_COUNT,
		.access = (OP_READ | OP_WRITE),
		.packed_size = SJA1105PQRS_SIZE_MAC_CONFIG_DYN_CMD,
		.addr = 0x4B,
	},
	[BLK_IDX_L2_LOOKUP_PARAMS] = {
		.entry_packing = sja1105et_l2_lookup_params_entry_packing,
		.cmd_packing = sja1105et_l2_lookup_params_cmd_packing,
		.max_entry_count = SJA1105_MAX_L2_LOOKUP_PARAMS_COUNT,
		.access = (OP_READ | OP_WRITE),
		.packed_size = SJA1105ET_SIZE_L2_LOOKUP_PARAMS_DYN_CMD,
		.addr = 0x38,
	},
	[BLK_IDX_L2_FORWARDING_PARAMS] = {0},
	[BLK_IDX_GENERAL_PARAMS] = {
		.entry_packing = sja1105et_general_params_entry_packing,
		.cmd_packing = sja1105et_general_params_cmd_packing,
		.max_entry_count = SJA1105_MAX_GENERAL_PARAMS_COUNT,
		.access = OP_WRITE,
		.packed_size = SJA1105ET_SIZE_GENERAL_PARAMS_DYN_CMD,
		.addr = 0x34,
	},
	[BLK_IDX_XMII_PARAMS] = {0},
};

int sja1105_dynamic_config_read(struct sja1105_private *priv,
				enum sja1105_blk_idx blk_idx,
				int index, void *entry)
{
	const struct sja1105_dynamic_table_ops *ops;
	struct sja1105_dyn_cmd cmd = {0};
	/* SPI payload buffer */
	u8 packed_buf[SJA1105_MAX_DYN_CMD_SIZE] = {0};
	int retries = 3;
	int rc;

	if (blk_idx >= BLK_IDX_MAX_DYN)
		return -ERANGE;

	ops = &priv->info->dyn_ops[blk_idx];

	if (index >= ops->max_entry_count)
		return -ERANGE;
	if (!(ops->access & OP_READ))
		return -EOPNOTSUPP;
	if (ops->packed_size > SJA1105_MAX_DYN_CMD_SIZE)
		return -ERANGE;
	if (!ops->cmd_packing)
		return -EOPNOTSUPP;
	if (!ops->entry_packing)
		return -EOPNOTSUPP;

	cmd.valid = true; /* Trigger action on table entry */
	cmd.rdwrset = SPI_READ; /* Action is read */
	cmd.index = index;
	ops->cmd_packing(packed_buf, &cmd, PACK);

	/* Send SPI write operation: read config table entry */
	rc = sja1105_spi_send_packed_buf(priv, SPI_WRITE, ops->addr,
					 packed_buf, ops->packed_size);
	if (rc < 0)
		return rc;

	/* Loop until we have confirmation that hardware has finished
	 * processing the command and has cleared the VALID field
	 */
	do {
		memset(packed_buf, 0, ops->packed_size);

		/* Retrieve the read operation's result */
		rc = sja1105_spi_send_packed_buf(priv, SPI_READ, ops->addr,
						 packed_buf, ops->packed_size);
		if (rc < 0)
			return rc;

		cmd = (struct sja1105_dyn_cmd) {0};
		ops->cmd_packing(packed_buf, &cmd, UNPACK);
		/* UM10944: [valident] will always be found cleared
		 * during a read access with MGMTROUTE set.
		 * So don't error out in that case.
		 */
		if (!cmd.valident && blk_idx != BLK_IDX_MGMT_ROUTE)
			return -EINVAL;
		cpu_relax();
	} while (cmd.valid && --retries);

	if (cmd.valid)
		return -ETIMEDOUT;

	/* Don't dereference possibly NULL pointer - maybe caller
	 * only wanted to see whether the entry existed or not.
	 */
	if (entry)
		ops->entry_packing(packed_buf, entry, UNPACK);
	return 0;
}

int sja1105_dynamic_config_write(struct sja1105_private *priv,
				 enum sja1105_blk_idx blk_idx,
				 int index, void *entry, bool keep)
{
	const struct sja1105_dynamic_table_ops *ops;
	struct sja1105_dyn_cmd cmd = {0};
	/* SPI payload buffer */
	u8 packed_buf[SJA1105_MAX_DYN_CMD_SIZE] = {0};
	int rc;

	if (blk_idx >= BLK_IDX_MAX_DYN)
		return -ERANGE;

	ops = &priv->info->dyn_ops[blk_idx];

	if (index >= ops->max_entry_count)
		return -ERANGE;
	if (!(ops->access & OP_WRITE))
		return -EOPNOTSUPP;
	if (!keep && !(ops->access & OP_DEL))
		return -EOPNOTSUPP;
	if (ops->packed_size > SJA1105_MAX_DYN_CMD_SIZE)
		return -ERANGE;

	cmd.valident = keep; /* If false, deletes entry */
	cmd.valid = true; /* Trigger action on table entry */
	cmd.rdwrset = SPI_WRITE; /* Action is write */
	cmd.index = index;

	if (!ops->cmd_packing)
		return -EOPNOTSUPP;
	ops->cmd_packing(packed_buf, &cmd, PACK);

	if (!ops->entry_packing)
		return -EOPNOTSUPP;
	/* Don't dereference potentially NULL pointer if just
	 * deleting a table entry is what was requested. For cases
	 * where 'index' field is physically part of entry structure,
	 * and needed here, we deal with that in the cmd_packing callback.
	 */
	if (keep)
		ops->entry_packing(packed_buf, entry, PACK);

	/* Send SPI write operation: read config table entry */
	rc = sja1105_spi_send_packed_buf(priv, SPI_WRITE, ops->addr,
					 packed_buf, ops->packed_size);
	if (rc < 0)
		return rc;

	cmd = (struct sja1105_dyn_cmd) {0};
	ops->cmd_packing(packed_buf, &cmd, UNPACK);
	if (cmd.errors)
		return -EINVAL;

	return 0;
}

static u8 sja1105_crc8_add(u8 crc, u8 byte, u8 poly)
{
	int i;

	for (i = 0; i < 8; i++) {
		if ((crc ^ byte) & (1 << 7)) {
			crc <<= 1;
			crc ^= poly;
		} else {
			crc <<= 1;
		}
		byte <<= 1;
	}
	return crc;
}

/* CRC8 algorithm with non-reversed input, non-reversed output,
 * no input xor and no output xor. Code customized for receiving
 * the SJA1105 E/T FDB keys (vlanid, macaddr) as input. CRC polynomial
 * is also received as argument in the Koopman notation that the switch
 * hardware stores it in.
 */
u8 sja1105_fdb_hash(struct sja1105_private *priv, const u8 *addr, u16 vid)
{
	struct sja1105_l2_lookup_params_entry *l2_lookup_params =
		priv->static_config.tables[BLK_IDX_L2_LOOKUP_PARAMS].entries;
	u64 poly_koopman = l2_lookup_params->poly;
	/* Convert polynomial from Koopman to 'normal' notation */
	u8 poly = (u8)(1 + (poly_koopman << 1));
	u64 vlanid = l2_lookup_params->shared_learn ? 0 : vid;
	u64 input = (vlanid << 48) | ether_addr_to_u64(addr);
	u8 crc = 0; /* seed */
	int i;

	/* Mask the eight bytes starting from MSB one at a time */
	for (i = 56; i >= 0; i -= 8) {
		u8 byte = (input & (0xffull << i)) >> i;

		crc = sja1105_crc8_add(crc, byte, poly);
	}
	return crc;
}