/*
 * RSS and Classifier helpers for Marvell PPv2 Network Controller
 *
 * Copyright (C) 2014 Marvell
 *
 * Marcin Wojtas <mw@semihalf.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include "mvpp2.h"
#include "mvpp2_cls.h"

/* Update classification flow table registers */
static void mvpp2_cls_flow_write(struct mvpp2 *priv,
				 struct mvpp2_cls_flow_entry *fe)
{
	mvpp2_write(priv, MVPP2_CLS_FLOW_INDEX_REG, fe->index);
	mvpp2_write(priv, MVPP2_CLS_FLOW_TBL0_REG,  fe->data[0]);
	mvpp2_write(priv, MVPP2_CLS_FLOW_TBL1_REG,  fe->data[1]);
	mvpp2_write(priv, MVPP2_CLS_FLOW_TBL2_REG,  fe->data[2]);
}

/* Update classification lookup table register */
static void mvpp2_cls_lookup_write(struct mvpp2 *priv,
				   struct mvpp2_cls_lookup_entry *le)
{
	u32 val;

	val = (le->way << MVPP2_CLS_LKP_INDEX_WAY_OFFS) | le->lkpid;
	mvpp2_write(priv, MVPP2_CLS_LKP_INDEX_REG, val);
	mvpp2_write(priv, MVPP2_CLS_LKP_TBL_REG, le->data);
}

/* Classifier default initialization */
void mvpp2_cls_init(struct mvpp2 *priv)
{
	struct mvpp2_cls_lookup_entry le;
	struct mvpp2_cls_flow_entry fe;
	int index;

	/* Enable classifier */
	mvpp2_write(priv, MVPP2_CLS_MODE_REG, MVPP2_CLS_MODE_ACTIVE_MASK);

	/* Clear classifier flow table */
	memset(&fe.data, 0, sizeof(fe.data));
	for (index = 0; index < MVPP2_CLS_FLOWS_TBL_SIZE; index++) {
		fe.index = index;
		mvpp2_cls_flow_write(priv, &fe);
	}

	/* Clear classifier lookup table */
	le.data = 0;
	for (index = 0; index < MVPP2_CLS_LKP_TBL_SIZE; index++) {
		le.lkpid = index;
		le.way = 0;
		mvpp2_cls_lookup_write(priv, &le);

		le.way = 1;
		mvpp2_cls_lookup_write(priv, &le);
	}
}

void mvpp2_cls_port_config(struct mvpp2_port *port)
{
	struct mvpp2_cls_lookup_entry le;
	u32 val;

	/* Set way for the port */
	val = mvpp2_read(port->priv, MVPP2_CLS_PORT_WAY_REG);
	val &= ~MVPP2_CLS_PORT_WAY_MASK(port->id);
	mvpp2_write(port->priv, MVPP2_CLS_PORT_WAY_REG, val);

	/* Pick the entry to be accessed in lookup ID decoding table
	 * according to the way and lkpid.
	 */
	le.lkpid = port->id;
	le.way = 0;
	le.data = 0;

	/* Set initial CPU queue for receiving packets */
	le.data &= ~MVPP2_CLS_LKP_TBL_RXQ_MASK;
	le.data |= port->first_rxq;

	/* Disable classification engines */
	le.data &= ~MVPP2_CLS_LKP_TBL_LOOKUP_EN_MASK;

	/* Update lookup ID table entry */
	mvpp2_cls_lookup_write(port->priv, &le);
}

/* Set CPU queue number for oversize packets */
void mvpp2_cls_oversize_rxq_set(struct mvpp2_port *port)
{
	u32 val;

	mvpp2_write(port->priv, MVPP2_CLS_OVERSIZE_RXQ_LOW_REG(port->id),
		    port->first_rxq & MVPP2_CLS_OVERSIZE_RXQ_LOW_MASK);

	mvpp2_write(port->priv, MVPP2_CLS_SWFWD_P2HQ_REG(port->id),
		    (port->first_rxq >> MVPP2_CLS_OVERSIZE_RXQ_LOW_BITS));

	val = mvpp2_read(port->priv, MVPP2_CLS_SWFWD_PCTRL_REG);
	val |= MVPP2_CLS_SWFWD_PCTRL_MASK(port->id);
	mvpp2_write(port->priv, MVPP2_CLS_SWFWD_PCTRL_REG, val);
}

static inline u32 mvpp22_rxfh_indir(struct mvpp2_port *port, u32 rxq)
{
	int nrxqs, cpus = num_possible_cpus();

	/* Number of RXQs per CPU */
	nrxqs = port->nrxqs / cpus;

	/* Indirection to better distribute the paquets on the CPUs when
	 * configuring the RSS queues.
	 */
	return port->first_rxq + ((rxq * nrxqs + rxq / cpus) % port->nrxqs);
}

void mvpp22_rss_fill_table(struct mvpp2_port *port, u32 table)
{
	struct mvpp2 *priv = port->priv;
	int i;

	for (i = 0; i < MVPP22_RSS_TABLE_ENTRIES; i++) {
		u32 sel = MVPP22_RSS_INDEX_TABLE(table) |
			  MVPP22_RSS_INDEX_TABLE_ENTRY(i);
		mvpp2_write(priv, MVPP22_RSS_INDEX, sel);

		mvpp2_write(priv, MVPP22_RSS_TABLE_ENTRY,
			    mvpp22_rxfh_indir(port, port->indir[i]));
	}
}

void mvpp22_init_rss(struct mvpp2_port *port)
{
	struct mvpp2 *priv = port->priv;
	int i;

	/* Set the table width: replace the whole classifier Rx queue number
	 * with the ones configured in RSS table entries.
	 */
	mvpp2_write(priv, MVPP22_RSS_INDEX, MVPP22_RSS_INDEX_TABLE(port->id));
	mvpp2_write(priv, MVPP22_RSS_WIDTH, 8);

	/* The default RxQ is used as a key to select the RSS table to use.
	 * We use one RSS table per port.
	 */
	mvpp2_write(priv, MVPP22_RSS_INDEX,
		    MVPP22_RSS_INDEX_QUEUE(port->first_rxq));
	mvpp2_write(priv, MVPP22_RXQ2RSS_TABLE,
		    MVPP22_RSS_TABLE_POINTER(port->id));

	/* Configure the first table to evenly distribute the packets across
	 * real Rx Queues. The table entries map a hash to a port Rx Queue.
	 */
	for (i = 0; i < MVPP22_RSS_TABLE_ENTRIES; i++)
		port->indir[i] = ethtool_rxfh_indir_default(i, port->nrxqs);

	mvpp22_rss_fill_table(port, port->id);
}