xref: /OK3568_Linux_fs/kernel/drivers/net/ethernet/sfc/falcon/mdio_10g.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /****************************************************************************
3*4882a593Smuzhiyun  * Driver for Solarflare network controllers and boards
4*4882a593Smuzhiyun  * Copyright 2006-2011 Solarflare Communications Inc.
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun /*
7*4882a593Smuzhiyun  * Useful functions for working with MDIO clause 45 PHYs
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun #include <linux/types.h>
10*4882a593Smuzhiyun #include <linux/ethtool.h>
11*4882a593Smuzhiyun #include <linux/delay.h>
12*4882a593Smuzhiyun #include "net_driver.h"
13*4882a593Smuzhiyun #include "mdio_10g.h"
14*4882a593Smuzhiyun #include "workarounds.h"
15*4882a593Smuzhiyun 
ef4_mdio_id_oui(u32 id)16*4882a593Smuzhiyun unsigned ef4_mdio_id_oui(u32 id)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun 	unsigned oui = 0;
19*4882a593Smuzhiyun 	int i;
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun 	/* The bits of the OUI are designated a..x, with a=0 and b variable.
22*4882a593Smuzhiyun 	 * In the id register c is the MSB but the OUI is conventionally
23*4882a593Smuzhiyun 	 * written as bytes h..a, p..i, x..q.  Reorder the bits accordingly. */
24*4882a593Smuzhiyun 	for (i = 0; i < 22; ++i)
25*4882a593Smuzhiyun 		if (id & (1 << (i + 10)))
26*4882a593Smuzhiyun 			oui |= 1 << (i ^ 7);
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	return oui;
29*4882a593Smuzhiyun }
30*4882a593Smuzhiyun 
ef4_mdio_reset_mmd(struct ef4_nic * port,int mmd,int spins,int spintime)31*4882a593Smuzhiyun int ef4_mdio_reset_mmd(struct ef4_nic *port, int mmd,
32*4882a593Smuzhiyun 			    int spins, int spintime)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun 	u32 ctrl;
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	/* Catch callers passing values in the wrong units (or just silly) */
37*4882a593Smuzhiyun 	EF4_BUG_ON_PARANOID(spins * spintime >= 5000);
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun 	ef4_mdio_write(port, mmd, MDIO_CTRL1, MDIO_CTRL1_RESET);
40*4882a593Smuzhiyun 	/* Wait for the reset bit to clear. */
41*4882a593Smuzhiyun 	do {
42*4882a593Smuzhiyun 		msleep(spintime);
43*4882a593Smuzhiyun 		ctrl = ef4_mdio_read(port, mmd, MDIO_CTRL1);
44*4882a593Smuzhiyun 		spins--;
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	} while (spins && (ctrl & MDIO_CTRL1_RESET));
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun 	return spins ? spins : -ETIMEDOUT;
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun 
ef4_mdio_check_mmd(struct ef4_nic * efx,int mmd)51*4882a593Smuzhiyun static int ef4_mdio_check_mmd(struct ef4_nic *efx, int mmd)
52*4882a593Smuzhiyun {
53*4882a593Smuzhiyun 	int status;
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun 	if (mmd != MDIO_MMD_AN) {
56*4882a593Smuzhiyun 		/* Read MMD STATUS2 to check it is responding. */
57*4882a593Smuzhiyun 		status = ef4_mdio_read(efx, mmd, MDIO_STAT2);
58*4882a593Smuzhiyun 		if ((status & MDIO_STAT2_DEVPRST) != MDIO_STAT2_DEVPRST_VAL) {
59*4882a593Smuzhiyun 			netif_err(efx, hw, efx->net_dev,
60*4882a593Smuzhiyun 				  "PHY MMD %d not responding.\n", mmd);
61*4882a593Smuzhiyun 			return -EIO;
62*4882a593Smuzhiyun 		}
63*4882a593Smuzhiyun 	}
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	return 0;
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun /* This ought to be ridiculous overkill. We expect it to fail rarely */
69*4882a593Smuzhiyun #define MDIO45_RESET_TIME	1000 /* ms */
70*4882a593Smuzhiyun #define MDIO45_RESET_ITERS	100
71*4882a593Smuzhiyun 
ef4_mdio_wait_reset_mmds(struct ef4_nic * efx,unsigned int mmd_mask)72*4882a593Smuzhiyun int ef4_mdio_wait_reset_mmds(struct ef4_nic *efx, unsigned int mmd_mask)
73*4882a593Smuzhiyun {
74*4882a593Smuzhiyun 	const int spintime = MDIO45_RESET_TIME / MDIO45_RESET_ITERS;
75*4882a593Smuzhiyun 	int tries = MDIO45_RESET_ITERS;
76*4882a593Smuzhiyun 	int rc = 0;
77*4882a593Smuzhiyun 	int in_reset;
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun 	while (tries) {
80*4882a593Smuzhiyun 		int mask = mmd_mask;
81*4882a593Smuzhiyun 		int mmd = 0;
82*4882a593Smuzhiyun 		int stat;
83*4882a593Smuzhiyun 		in_reset = 0;
84*4882a593Smuzhiyun 		while (mask) {
85*4882a593Smuzhiyun 			if (mask & 1) {
86*4882a593Smuzhiyun 				stat = ef4_mdio_read(efx, mmd, MDIO_CTRL1);
87*4882a593Smuzhiyun 				if (stat < 0) {
88*4882a593Smuzhiyun 					netif_err(efx, hw, efx->net_dev,
89*4882a593Smuzhiyun 						  "failed to read status of"
90*4882a593Smuzhiyun 						  " MMD %d\n", mmd);
91*4882a593Smuzhiyun 					return -EIO;
92*4882a593Smuzhiyun 				}
93*4882a593Smuzhiyun 				if (stat & MDIO_CTRL1_RESET)
94*4882a593Smuzhiyun 					in_reset |= (1 << mmd);
95*4882a593Smuzhiyun 			}
96*4882a593Smuzhiyun 			mask = mask >> 1;
97*4882a593Smuzhiyun 			mmd++;
98*4882a593Smuzhiyun 		}
99*4882a593Smuzhiyun 		if (!in_reset)
100*4882a593Smuzhiyun 			break;
101*4882a593Smuzhiyun 		tries--;
102*4882a593Smuzhiyun 		msleep(spintime);
103*4882a593Smuzhiyun 	}
104*4882a593Smuzhiyun 	if (in_reset != 0) {
105*4882a593Smuzhiyun 		netif_err(efx, hw, efx->net_dev,
106*4882a593Smuzhiyun 			  "not all MMDs came out of reset in time."
107*4882a593Smuzhiyun 			  " MMDs still in reset: %x\n", in_reset);
108*4882a593Smuzhiyun 		rc = -ETIMEDOUT;
109*4882a593Smuzhiyun 	}
110*4882a593Smuzhiyun 	return rc;
111*4882a593Smuzhiyun }
112*4882a593Smuzhiyun 
ef4_mdio_check_mmds(struct ef4_nic * efx,unsigned int mmd_mask)113*4882a593Smuzhiyun int ef4_mdio_check_mmds(struct ef4_nic *efx, unsigned int mmd_mask)
114*4882a593Smuzhiyun {
115*4882a593Smuzhiyun 	int mmd = 0, probe_mmd, devs1, devs2;
116*4882a593Smuzhiyun 	u32 devices;
117*4882a593Smuzhiyun 
118*4882a593Smuzhiyun 	/* Historically we have probed the PHYXS to find out what devices are
119*4882a593Smuzhiyun 	 * present,but that doesn't work so well if the PHYXS isn't expected
120*4882a593Smuzhiyun 	 * to exist, if so just find the first item in the list supplied. */
121*4882a593Smuzhiyun 	probe_mmd = (mmd_mask & MDIO_DEVS_PHYXS) ? MDIO_MMD_PHYXS :
122*4882a593Smuzhiyun 	    __ffs(mmd_mask);
123*4882a593Smuzhiyun 
124*4882a593Smuzhiyun 	/* Check all the expected MMDs are present */
125*4882a593Smuzhiyun 	devs1 = ef4_mdio_read(efx, probe_mmd, MDIO_DEVS1);
126*4882a593Smuzhiyun 	devs2 = ef4_mdio_read(efx, probe_mmd, MDIO_DEVS2);
127*4882a593Smuzhiyun 	if (devs1 < 0 || devs2 < 0) {
128*4882a593Smuzhiyun 		netif_err(efx, hw, efx->net_dev,
129*4882a593Smuzhiyun 			  "failed to read devices present\n");
130*4882a593Smuzhiyun 		return -EIO;
131*4882a593Smuzhiyun 	}
132*4882a593Smuzhiyun 	devices = devs1 | (devs2 << 16);
133*4882a593Smuzhiyun 	if ((devices & mmd_mask) != mmd_mask) {
134*4882a593Smuzhiyun 		netif_err(efx, hw, efx->net_dev,
135*4882a593Smuzhiyun 			  "required MMDs not present: got %x, wanted %x\n",
136*4882a593Smuzhiyun 			  devices, mmd_mask);
137*4882a593Smuzhiyun 		return -ENODEV;
138*4882a593Smuzhiyun 	}
139*4882a593Smuzhiyun 	netif_vdbg(efx, hw, efx->net_dev, "Devices present: %x\n", devices);
140*4882a593Smuzhiyun 
141*4882a593Smuzhiyun 	/* Check all required MMDs are responding and happy. */
142*4882a593Smuzhiyun 	while (mmd_mask) {
143*4882a593Smuzhiyun 		if ((mmd_mask & 1) && ef4_mdio_check_mmd(efx, mmd))
144*4882a593Smuzhiyun 			return -EIO;
145*4882a593Smuzhiyun 		mmd_mask = mmd_mask >> 1;
146*4882a593Smuzhiyun 		mmd++;
147*4882a593Smuzhiyun 	}
148*4882a593Smuzhiyun 
149*4882a593Smuzhiyun 	return 0;
150*4882a593Smuzhiyun }
151*4882a593Smuzhiyun 
ef4_mdio_links_ok(struct ef4_nic * efx,unsigned int mmd_mask)152*4882a593Smuzhiyun bool ef4_mdio_links_ok(struct ef4_nic *efx, unsigned int mmd_mask)
153*4882a593Smuzhiyun {
154*4882a593Smuzhiyun 	/* If the port is in loopback, then we should only consider a subset
155*4882a593Smuzhiyun 	 * of mmd's */
156*4882a593Smuzhiyun 	if (LOOPBACK_INTERNAL(efx))
157*4882a593Smuzhiyun 		return true;
158*4882a593Smuzhiyun 	else if (LOOPBACK_MASK(efx) & LOOPBACKS_WS)
159*4882a593Smuzhiyun 		return false;
160*4882a593Smuzhiyun 	else if (ef4_phy_mode_disabled(efx->phy_mode))
161*4882a593Smuzhiyun 		return false;
162*4882a593Smuzhiyun 	else if (efx->loopback_mode == LOOPBACK_PHYXS)
163*4882a593Smuzhiyun 		mmd_mask &= ~(MDIO_DEVS_PHYXS |
164*4882a593Smuzhiyun 			      MDIO_DEVS_PCS |
165*4882a593Smuzhiyun 			      MDIO_DEVS_PMAPMD |
166*4882a593Smuzhiyun 			      MDIO_DEVS_AN);
167*4882a593Smuzhiyun 	else if (efx->loopback_mode == LOOPBACK_PCS)
168*4882a593Smuzhiyun 		mmd_mask &= ~(MDIO_DEVS_PCS |
169*4882a593Smuzhiyun 			      MDIO_DEVS_PMAPMD |
170*4882a593Smuzhiyun 			      MDIO_DEVS_AN);
171*4882a593Smuzhiyun 	else if (efx->loopback_mode == LOOPBACK_PMAPMD)
172*4882a593Smuzhiyun 		mmd_mask &= ~(MDIO_DEVS_PMAPMD |
173*4882a593Smuzhiyun 			      MDIO_DEVS_AN);
174*4882a593Smuzhiyun 
175*4882a593Smuzhiyun 	return mdio45_links_ok(&efx->mdio, mmd_mask);
176*4882a593Smuzhiyun }
177*4882a593Smuzhiyun 
ef4_mdio_transmit_disable(struct ef4_nic * efx)178*4882a593Smuzhiyun void ef4_mdio_transmit_disable(struct ef4_nic *efx)
179*4882a593Smuzhiyun {
180*4882a593Smuzhiyun 	ef4_mdio_set_flag(efx, MDIO_MMD_PMAPMD,
181*4882a593Smuzhiyun 			  MDIO_PMA_TXDIS, MDIO_PMD_TXDIS_GLOBAL,
182*4882a593Smuzhiyun 			  efx->phy_mode & PHY_MODE_TX_DISABLED);
183*4882a593Smuzhiyun }
184*4882a593Smuzhiyun 
ef4_mdio_phy_reconfigure(struct ef4_nic * efx)185*4882a593Smuzhiyun void ef4_mdio_phy_reconfigure(struct ef4_nic *efx)
186*4882a593Smuzhiyun {
187*4882a593Smuzhiyun 	ef4_mdio_set_flag(efx, MDIO_MMD_PMAPMD,
188*4882a593Smuzhiyun 			  MDIO_CTRL1, MDIO_PMA_CTRL1_LOOPBACK,
189*4882a593Smuzhiyun 			  efx->loopback_mode == LOOPBACK_PMAPMD);
190*4882a593Smuzhiyun 	ef4_mdio_set_flag(efx, MDIO_MMD_PCS,
191*4882a593Smuzhiyun 			  MDIO_CTRL1, MDIO_PCS_CTRL1_LOOPBACK,
192*4882a593Smuzhiyun 			  efx->loopback_mode == LOOPBACK_PCS);
193*4882a593Smuzhiyun 	ef4_mdio_set_flag(efx, MDIO_MMD_PHYXS,
194*4882a593Smuzhiyun 			  MDIO_CTRL1, MDIO_PHYXS_CTRL1_LOOPBACK,
195*4882a593Smuzhiyun 			  efx->loopback_mode == LOOPBACK_PHYXS_WS);
196*4882a593Smuzhiyun }
197*4882a593Smuzhiyun 
ef4_mdio_set_mmd_lpower(struct ef4_nic * efx,int lpower,int mmd)198*4882a593Smuzhiyun static void ef4_mdio_set_mmd_lpower(struct ef4_nic *efx,
199*4882a593Smuzhiyun 				    int lpower, int mmd)
200*4882a593Smuzhiyun {
201*4882a593Smuzhiyun 	int stat = ef4_mdio_read(efx, mmd, MDIO_STAT1);
202*4882a593Smuzhiyun 
203*4882a593Smuzhiyun 	netif_vdbg(efx, drv, efx->net_dev, "Setting low power mode for MMD %d to %d\n",
204*4882a593Smuzhiyun 		  mmd, lpower);
205*4882a593Smuzhiyun 
206*4882a593Smuzhiyun 	if (stat & MDIO_STAT1_LPOWERABLE) {
207*4882a593Smuzhiyun 		ef4_mdio_set_flag(efx, mmd, MDIO_CTRL1,
208*4882a593Smuzhiyun 				  MDIO_CTRL1_LPOWER, lpower);
209*4882a593Smuzhiyun 	}
210*4882a593Smuzhiyun }
211*4882a593Smuzhiyun 
ef4_mdio_set_mmds_lpower(struct ef4_nic * efx,int low_power,unsigned int mmd_mask)212*4882a593Smuzhiyun void ef4_mdio_set_mmds_lpower(struct ef4_nic *efx,
213*4882a593Smuzhiyun 			      int low_power, unsigned int mmd_mask)
214*4882a593Smuzhiyun {
215*4882a593Smuzhiyun 	int mmd = 0;
216*4882a593Smuzhiyun 	mmd_mask &= ~MDIO_DEVS_AN;
217*4882a593Smuzhiyun 	while (mmd_mask) {
218*4882a593Smuzhiyun 		if (mmd_mask & 1)
219*4882a593Smuzhiyun 			ef4_mdio_set_mmd_lpower(efx, low_power, mmd);
220*4882a593Smuzhiyun 		mmd_mask = (mmd_mask >> 1);
221*4882a593Smuzhiyun 		mmd++;
222*4882a593Smuzhiyun 	}
223*4882a593Smuzhiyun }
224*4882a593Smuzhiyun 
225*4882a593Smuzhiyun /**
226*4882a593Smuzhiyun  * ef4_mdio_set_link_ksettings - Set (some of) the PHY settings over MDIO.
227*4882a593Smuzhiyun  * @efx:		Efx NIC
228*4882a593Smuzhiyun  * @cmd:		New settings
229*4882a593Smuzhiyun  */
ef4_mdio_set_link_ksettings(struct ef4_nic * efx,const struct ethtool_link_ksettings * cmd)230*4882a593Smuzhiyun int ef4_mdio_set_link_ksettings(struct ef4_nic *efx,
231*4882a593Smuzhiyun 				const struct ethtool_link_ksettings *cmd)
232*4882a593Smuzhiyun {
233*4882a593Smuzhiyun 	struct ethtool_link_ksettings prev = {
234*4882a593Smuzhiyun 		.base.cmd = ETHTOOL_GLINKSETTINGS
235*4882a593Smuzhiyun 	};
236*4882a593Smuzhiyun 	u32 prev_advertising, advertising;
237*4882a593Smuzhiyun 	u32 prev_supported;
238*4882a593Smuzhiyun 
239*4882a593Smuzhiyun 	efx->phy_op->get_link_ksettings(efx, &prev);
240*4882a593Smuzhiyun 
241*4882a593Smuzhiyun 	ethtool_convert_link_mode_to_legacy_u32(&advertising,
242*4882a593Smuzhiyun 						cmd->link_modes.advertising);
243*4882a593Smuzhiyun 	ethtool_convert_link_mode_to_legacy_u32(&prev_advertising,
244*4882a593Smuzhiyun 						prev.link_modes.advertising);
245*4882a593Smuzhiyun 	ethtool_convert_link_mode_to_legacy_u32(&prev_supported,
246*4882a593Smuzhiyun 						prev.link_modes.supported);
247*4882a593Smuzhiyun 
248*4882a593Smuzhiyun 	if (advertising == prev_advertising &&
249*4882a593Smuzhiyun 	    cmd->base.speed == prev.base.speed &&
250*4882a593Smuzhiyun 	    cmd->base.duplex == prev.base.duplex &&
251*4882a593Smuzhiyun 	    cmd->base.port == prev.base.port &&
252*4882a593Smuzhiyun 	    cmd->base.autoneg == prev.base.autoneg)
253*4882a593Smuzhiyun 		return 0;
254*4882a593Smuzhiyun 
255*4882a593Smuzhiyun 	/* We can only change these settings for -T PHYs */
256*4882a593Smuzhiyun 	if (prev.base.port != PORT_TP || cmd->base.port != PORT_TP)
257*4882a593Smuzhiyun 		return -EINVAL;
258*4882a593Smuzhiyun 
259*4882a593Smuzhiyun 	/* Check that PHY supports these settings */
260*4882a593Smuzhiyun 	if (!cmd->base.autoneg ||
261*4882a593Smuzhiyun 	    (advertising | SUPPORTED_Autoneg) & ~prev_supported)
262*4882a593Smuzhiyun 		return -EINVAL;
263*4882a593Smuzhiyun 
264*4882a593Smuzhiyun 	ef4_link_set_advertising(efx, advertising | ADVERTISED_Autoneg);
265*4882a593Smuzhiyun 	ef4_mdio_an_reconfigure(efx);
266*4882a593Smuzhiyun 	return 0;
267*4882a593Smuzhiyun }
268*4882a593Smuzhiyun 
269*4882a593Smuzhiyun /**
270*4882a593Smuzhiyun  * ef4_mdio_an_reconfigure - Push advertising flags and restart autonegotiation
271*4882a593Smuzhiyun  * @efx:		Efx NIC
272*4882a593Smuzhiyun  */
ef4_mdio_an_reconfigure(struct ef4_nic * efx)273*4882a593Smuzhiyun void ef4_mdio_an_reconfigure(struct ef4_nic *efx)
274*4882a593Smuzhiyun {
275*4882a593Smuzhiyun 	int reg;
276*4882a593Smuzhiyun 
277*4882a593Smuzhiyun 	WARN_ON(!(efx->mdio.mmds & MDIO_DEVS_AN));
278*4882a593Smuzhiyun 
279*4882a593Smuzhiyun 	/* Set up the base page */
280*4882a593Smuzhiyun 	reg = ADVERTISE_CSMA | ADVERTISE_RESV;
281*4882a593Smuzhiyun 	if (efx->link_advertising & ADVERTISED_Pause)
282*4882a593Smuzhiyun 		reg |= ADVERTISE_PAUSE_CAP;
283*4882a593Smuzhiyun 	if (efx->link_advertising & ADVERTISED_Asym_Pause)
284*4882a593Smuzhiyun 		reg |= ADVERTISE_PAUSE_ASYM;
285*4882a593Smuzhiyun 	ef4_mdio_write(efx, MDIO_MMD_AN, MDIO_AN_ADVERTISE, reg);
286*4882a593Smuzhiyun 
287*4882a593Smuzhiyun 	/* Set up the (extended) next page */
288*4882a593Smuzhiyun 	efx->phy_op->set_npage_adv(efx, efx->link_advertising);
289*4882a593Smuzhiyun 
290*4882a593Smuzhiyun 	/* Enable and restart AN */
291*4882a593Smuzhiyun 	reg = ef4_mdio_read(efx, MDIO_MMD_AN, MDIO_CTRL1);
292*4882a593Smuzhiyun 	reg |= MDIO_AN_CTRL1_ENABLE | MDIO_AN_CTRL1_RESTART | MDIO_AN_CTRL1_XNP;
293*4882a593Smuzhiyun 	ef4_mdio_write(efx, MDIO_MMD_AN, MDIO_CTRL1, reg);
294*4882a593Smuzhiyun }
295*4882a593Smuzhiyun 
ef4_mdio_get_pause(struct ef4_nic * efx)296*4882a593Smuzhiyun u8 ef4_mdio_get_pause(struct ef4_nic *efx)
297*4882a593Smuzhiyun {
298*4882a593Smuzhiyun 	BUILD_BUG_ON(EF4_FC_AUTO & (EF4_FC_RX | EF4_FC_TX));
299*4882a593Smuzhiyun 
300*4882a593Smuzhiyun 	if (!(efx->wanted_fc & EF4_FC_AUTO))
301*4882a593Smuzhiyun 		return efx->wanted_fc;
302*4882a593Smuzhiyun 
303*4882a593Smuzhiyun 	WARN_ON(!(efx->mdio.mmds & MDIO_DEVS_AN));
304*4882a593Smuzhiyun 
305*4882a593Smuzhiyun 	return mii_resolve_flowctrl_fdx(
306*4882a593Smuzhiyun 		mii_advertise_flowctrl(efx->wanted_fc),
307*4882a593Smuzhiyun 		ef4_mdio_read(efx, MDIO_MMD_AN, MDIO_AN_LPA));
308*4882a593Smuzhiyun }
309*4882a593Smuzhiyun 
ef4_mdio_test_alive(struct ef4_nic * efx)310*4882a593Smuzhiyun int ef4_mdio_test_alive(struct ef4_nic *efx)
311*4882a593Smuzhiyun {
312*4882a593Smuzhiyun 	int rc;
313*4882a593Smuzhiyun 	int devad = __ffs(efx->mdio.mmds);
314*4882a593Smuzhiyun 	u16 physid1, physid2;
315*4882a593Smuzhiyun 
316*4882a593Smuzhiyun 	mutex_lock(&efx->mac_lock);
317*4882a593Smuzhiyun 
318*4882a593Smuzhiyun 	physid1 = ef4_mdio_read(efx, devad, MDIO_DEVID1);
319*4882a593Smuzhiyun 	physid2 = ef4_mdio_read(efx, devad, MDIO_DEVID2);
320*4882a593Smuzhiyun 
321*4882a593Smuzhiyun 	if ((physid1 == 0x0000) || (physid1 == 0xffff) ||
322*4882a593Smuzhiyun 	    (physid2 == 0x0000) || (physid2 == 0xffff)) {
323*4882a593Smuzhiyun 		netif_err(efx, hw, efx->net_dev,
324*4882a593Smuzhiyun 			  "no MDIO PHY present with ID %d\n", efx->mdio.prtad);
325*4882a593Smuzhiyun 		rc = -EINVAL;
326*4882a593Smuzhiyun 	} else {
327*4882a593Smuzhiyun 		rc = ef4_mdio_check_mmds(efx, efx->mdio.mmds);
328*4882a593Smuzhiyun 	}
329*4882a593Smuzhiyun 
330*4882a593Smuzhiyun 	mutex_unlock(&efx->mac_lock);
331*4882a593Smuzhiyun 	return rc;
332*4882a593Smuzhiyun }
333