include/linux/mii.h

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 * linux/mii.h: definitions for MII-compatible transceivers
 * Originally drivers/net/sunhme.h.
 *
 * Copyright (C) 1996, 1999, 2001 David S. Miller (davem@redhat.com)
 */

#ifndef __LINUX_MII_H__
#define __LINUX_MII_H__

/* Generic MII registers. */
#define MII_BMCR		0x00	/* Basic mode control register */
#define MII_BMSR		0x01	/* Basic mode status register  */
#define MII_PHYSID1		0x02	/* PHYS ID 1                   */
#define MII_PHYSID2		0x03	/* PHYS ID 2                   */
#define MII_ADVERTISE		0x04	/* Advertisement control reg   */
#define MII_LPA			0x05	/* Link partner ability reg    */
#define MII_EXPANSION		0x06	/* Expansion register          */
#define MII_CTRL1000		0x09	/* 1000BASE-T control          */
#define MII_STAT1000		0x0a	/* 1000BASE-T status           */
#define MII_MMD_CTRL		0x0d	/* MMD Access Control Register */
#define MII_MMD_DATA		0x0e	/* MMD Access Data Register */
#define MII_ESTATUS		0x0f	/* Extended Status             */
#define MII_DCOUNTER		0x12	/* Disconnect counter          */
#define MII_FCSCOUNTER		0x13	/* False carrier counter       */
#define MII_NWAYTEST		0x14	/* N-way auto-neg test reg     */
#define MII_RERRCOUNTER		0x15	/* Receive error counter       */
#define MII_SREVISION		0x16	/* Silicon revision            */
#define MII_RESV1		0x17	/* Reserved...                 */
#define MII_LBRERROR		0x18	/* Lpback, rx, bypass error    */
#define MII_PHYADDR		0x19	/* PHY address                 */
#define MII_RESV2		0x1a	/* Reserved...                 */
#define MII_TPISTATUS		0x1b	/* TPI status for 10mbps       */
#define MII_NCONFIG		0x1c	/* Network interface config    */

/* Basic mode control register. */
#define BMCR_RESV		0x003f	/* Unused...                   */
#define BMCR_SPEED1000		0x0040	/* MSB of Speed (1000)         */
#define BMCR_CTST		0x0080	/* Collision test              */
#define BMCR_FULLDPLX		0x0100	/* Full duplex                 */
#define BMCR_ANRESTART		0x0200	/* Auto negotiation restart    */
#define BMCR_ISOLATE		0x0400	/* Isolate data paths from MII */
#define BMCR_PDOWN		0x0800	/* Enable low power state      */
#define BMCR_ANENABLE		0x1000	/* Enable auto negotiation     */
#define BMCR_SPEED100		0x2000	/* Select 100Mbps              */
#define BMCR_LOOPBACK		0x4000	/* TXD loopback bits           */
#define BMCR_RESET		0x8000	/* Reset to default state      */
#define BMCR_SPEED10		0x0000	/* Select 10Mbps               */

/* Basic mode status register. */
#define BMSR_ERCAP		0x0001	/* Ext-reg capability          */
#define BMSR_JCD		0x0002	/* Jabber detected             */
#define BMSR_LSTATUS		0x0004	/* Link status                 */
#define BMSR_ANEGCAPABLE	0x0008	/* Able to do auto-negotiation */
#define BMSR_RFAULT		0x0010	/* Remote fault detected       */
#define BMSR_ANEGCOMPLETE	0x0020	/* Auto-negotiation complete   */
#define BMSR_RESV		0x00c0	/* Unused...                   */
#define BMSR_ESTATEN		0x0100	/* Extended Status in R15      */
#define BMSR_100HALF2		0x0200	/* Can do 100BASE-T2 HDX       */
#define BMSR_100FULL2		0x0400	/* Can do 100BASE-T2 FDX       */
#define BMSR_10HALF		0x0800	/* Can do 10mbps, half-duplex  */
#define BMSR_10FULL		0x1000	/* Can do 10mbps, full-duplex  */
#define BMSR_100HALF		0x2000	/* Can do 100mbps, half-duplex */
#define BMSR_100FULL		0x4000	/* Can do 100mbps, full-duplex */
#define BMSR_100BASE4		0x8000	/* Can do 100mbps, 4k packets  */

/* Advertisement control register. */
#define ADVERTISE_SLCT		0x001f	/* Selector bits               */
#define ADVERTISE_CSMA		0x0001	/* Only selector supported     */
#define ADVERTISE_10HALF	0x0020	/* Try for 10mbps half-duplex  */
#define ADVERTISE_1000XFULL	0x0020	/* Try for 1000BASE-X full-duplex */
#define ADVERTISE_10FULL	0x0040	/* Try for 10mbps full-duplex  */
#define ADVERTISE_1000XHALF	0x0040	/* Try for 1000BASE-X half-duplex */
#define ADVERTISE_100HALF	0x0080	/* Try for 100mbps half-duplex */
#define ADVERTISE_1000XPAUSE	0x0080	/* Try for 1000BASE-X pause    */
#define ADVERTISE_100FULL	0x0100	/* Try for 100mbps full-duplex */
#define ADVERTISE_1000XPSE_ASYM	0x0100	/* Try for 1000BASE-X asym pause */
#define ADVERTISE_100BASE4	0x0200	/* Try for 100mbps 4k packets  */
#define ADVERTISE_PAUSE_CAP	0x0400	/* Try for pause               */
#define ADVERTISE_PAUSE_ASYM	0x0800	/* Try for asymetric pause     */
#define ADVERTISE_RESV		0x1000	/* Unused...                   */
#define ADVERTISE_RFAULT	0x2000	/* Say we can detect faults    */
#define ADVERTISE_LPACK		0x4000	/* Ack link partners response  */
#define ADVERTISE_NPAGE		0x8000	/* Next page bit               */

#define ADVERTISE_FULL		(ADVERTISE_100FULL | ADVERTISE_10FULL | \
				 ADVERTISE_CSMA)
#define ADVERTISE_ALL		(ADVERTISE_10HALF | ADVERTISE_10FULL | \
				 ADVERTISE_100HALF | ADVERTISE_100FULL)

/* Link partner ability register. */
#define LPA_SLCT		0x001f	/* Same as advertise selector  */
#define LPA_10HALF		0x0020	/* Can do 10mbps half-duplex   */
#define LPA_1000XFULL		0x0020	/* Can do 1000BASE-X full-duplex */
#define LPA_10FULL		0x0040	/* Can do 10mbps full-duplex   */
#define LPA_1000XHALF		0x0040	/* Can do 1000BASE-X half-duplex */
#define LPA_100HALF		0x0080	/* Can do 100mbps half-duplex  */
#define LPA_1000XPAUSE		0x0080	/* Can do 1000BASE-X pause     */
#define LPA_100FULL		0x0100	/* Can do 100mbps full-duplex  */
#define LPA_1000XPAUSE_ASYM	0x0100	/* Can do 1000BASE-X pause asym*/
#define LPA_100BASE4		0x0200	/* Can do 100mbps 4k packets   */
#define LPA_PAUSE_CAP		0x0400	/* Can pause                   */
#define LPA_PAUSE_ASYM		0x0800	/* Can pause asymetrically     */
#define LPA_RESV		0x1000	/* Unused...                   */
#define LPA_RFAULT		0x2000	/* Link partner faulted        */
#define LPA_LPACK		0x4000	/* Link partner acked us       */
#define LPA_NPAGE		0x8000	/* Next page bit               */

#define LPA_DUPLEX		(LPA_10FULL | LPA_100FULL)
#define LPA_100			(LPA_100FULL | LPA_100HALF | LPA_100BASE4)

/* Expansion register for auto-negotiation. */
#define EXPANSION_NWAY		0x0001	/* Can do N-way auto-nego      */
#define EXPANSION_LCWP		0x0002	/* Got new RX page code word   */
#define EXPANSION_ENABLENPAGE	0x0004	/* This enables npage words    */
#define EXPANSION_NPCAPABLE	0x0008	/* Link partner supports npage */
#define EXPANSION_MFAULTS	0x0010	/* Multiple faults detected    */
#define EXPANSION_RESV		0xffe0	/* Unused...                   */

#define ESTATUS_1000_XFULL	0x8000	/* Can do 1000BX Full */
#define ESTATUS_1000_XHALF	0x4000	/* Can do 1000BX Half */
#define ESTATUS_1000_TFULL	0x2000	/* Can do 1000BT Full          */
#define ESTATUS_1000_THALF	0x1000	/* Can do 1000BT Half          */

/* N-way test register. */
#define NWAYTEST_RESV1		0x00ff	/* Unused...                   */
#define NWAYTEST_LOOPBACK	0x0100	/* Enable loopback for N-way   */
#define NWAYTEST_RESV2		0xfe00	/* Unused...                   */

/* 1000BASE-T Control register */
#define ADVERTISE_1000FULL	0x0200  /* Advertise 1000BASE-T full duplex */
#define ADVERTISE_1000HALF	0x0100  /* Advertise 1000BASE-T half duplex */
#define CTL1000_AS_MASTER	0x0800
#define CTL1000_ENABLE_MASTER	0x1000

/* 1000BASE-T Status register */
#define LPA_1000LOCALRXOK	0x2000	/* Link partner local receiver status */
#define LPA_1000REMRXOK		0x1000	/* Link partner remote receiver status */
#define LPA_1000FULL		0x0800	/* Link partner 1000BASE-T full duplex */
#define LPA_1000HALF		0x0400	/* Link partner 1000BASE-T half duplex */

/* Flow control flags */
#define FLOW_CTRL_TX		0x01
#define FLOW_CTRL_RX		0x02

/* MMD Access Control register fields */
#define MII_MMD_CTRL_DEVAD_MASK	0x1f	/* Mask MMD DEVAD*/
#define MII_MMD_CTRL_ADDR	0x0000	/* Address */
#define MII_MMD_CTRL_NOINCR	0x4000	/* no post increment */
#define MII_MMD_CTRL_INCR_RDWT	0x8000	/* post increment on reads & writes */
#define MII_MMD_CTRL_INCR_ON_WT	0xC000	/* post increment on writes only */

/**
 * mii_nway_result
 * @negotiated: value of MII ANAR and'd with ANLPAR
 *
 * Given a set of MII abilities, check each bit and returns the
 * currently supported media, in the priority order defined by
 * IEEE 802.3u.  We use LPA_xxx constants but note this is not the
 * value of LPA solely, as described above.
 *
 * The one exception to IEEE 802.3u is that 100baseT4 is placed
 * between 100T-full and 100T-half.  If your phy does not support
 * 100T4 this is fine. If your phy places 100T4 elsewhere in the
 * priority order, you will need to roll your own function.
 */
static inline unsigned int mii_nway_result (unsigned int negotiated)
{
	unsigned int ret;

	if (negotiated & LPA_100FULL)
		ret = LPA_100FULL;
	else if (negotiated & LPA_100BASE4)
		ret = LPA_100BASE4;
	else if (negotiated & LPA_100HALF)
		ret = LPA_100HALF;
	else if (negotiated & LPA_10FULL)
		ret = LPA_10FULL;
	else
		ret = LPA_10HALF;

	return ret;
}

/**
 * mii_duplex
 * @duplex_lock: Non-zero if duplex is locked at full
 * @negotiated: value of MII ANAR and'd with ANLPAR
 *
 * A small helper function for a common case.  Returns one
 * if the media is operating or locked at full duplex, and
 * returns zero otherwise.
 */
static inline unsigned int mii_duplex (unsigned int duplex_lock,
				       unsigned int negotiated)
{
	if (duplex_lock)
		return 1;
	if (mii_nway_result(negotiated) & LPA_DUPLEX)
		return 1;
	return 0;
}

/**
 * mii_resolve_flowctrl_fdx
 * @lcladv: value of MII ADVERTISE register
 * @rmtadv: value of MII LPA register
 *
 * Resolve full duplex flow control as per IEEE 802.3-2005 table 28B-3
 */
static inline u8 mii_resolve_flowctrl_fdx(u16 lcladv, u16 rmtadv)
{
	u8 cap = 0;

	if (lcladv & rmtadv & ADVERTISE_PAUSE_CAP) {
		cap = FLOW_CTRL_TX | FLOW_CTRL_RX;
	} else if (lcladv & rmtadv & ADVERTISE_PAUSE_ASYM) {
		if (lcladv & ADVERTISE_PAUSE_CAP)
			cap = FLOW_CTRL_RX;
		else if (rmtadv & ADVERTISE_PAUSE_CAP)
			cap = FLOW_CTRL_TX;
	}

	return cap;
}

#endif /* __LINUX_MII_H__ */