New driver "sfc" for Solarstorm SFC4000 controller.

The driver supports the 10Xpress PHY and XFP modules on our reference
designs SFE4001 and SFE4002 and the SMC models SMC10GPCIe-XFP and
SMC10GPCIe-10BT.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/sfc/mdio_10g.c b/drivers/net/sfc/mdio_10g.c
new file mode 100644
index 0000000..dc06bb0
--- /dev/null
+++ b/drivers/net/sfc/mdio_10g.c
@@ -0,0 +1,282 @@
+/****************************************************************************
+ * Driver for Solarflare Solarstorm network controllers and boards
+ * Copyright 2006-2008 Solarflare Communications Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation, incorporated herein by reference.
+ */
+/*
+ * Useful functions for working with MDIO clause 45 PHYs
+ */
+#include <linux/types.h>
+#include <linux/ethtool.h>
+#include <linux/delay.h>
+#include "net_driver.h"
+#include "mdio_10g.h"
+#include "boards.h"
+
+int mdio_clause45_reset_mmd(struct efx_nic *port, int mmd,
+			    int spins, int spintime)
+{
+	u32 ctrl;
+	int phy_id = port->mii.phy_id;
+
+	/* Catch callers passing values in the wrong units (or just silly) */
+	EFX_BUG_ON_PARANOID(spins * spintime >= 5000);
+
+	mdio_clause45_write(port, phy_id, mmd, MDIO_MMDREG_CTRL1,
+			    (1 << MDIO_MMDREG_CTRL1_RESET_LBN));
+	/* Wait for the reset bit to clear. */
+	do {
+		msleep(spintime);
+		ctrl = mdio_clause45_read(port, phy_id, mmd, MDIO_MMDREG_CTRL1);
+		spins--;
+
+	} while (spins && (ctrl & (1 << MDIO_MMDREG_CTRL1_RESET_LBN)));
+
+	return spins ? spins : -ETIMEDOUT;
+}
+
+static int mdio_clause45_check_mmd(struct efx_nic *efx, int mmd,
+				   int fault_fatal)
+{
+	int status;
+	int phy_id = efx->mii.phy_id;
+
+	/* Read MMD STATUS2 to check it is responding. */
+	status = mdio_clause45_read(efx, phy_id, mmd, MDIO_MMDREG_STAT2);
+	if (((status >> MDIO_MMDREG_STAT2_PRESENT_LBN) &
+	     ((1 << MDIO_MMDREG_STAT2_PRESENT_WIDTH) - 1)) !=
+	    MDIO_MMDREG_STAT2_PRESENT_VAL) {
+		EFX_ERR(efx, "PHY MMD %d not responding.\n", mmd);
+		return -EIO;
+	}
+
+	/* Read MMD STATUS 1 to check for fault. */
+	status = mdio_clause45_read(efx, phy_id, mmd, MDIO_MMDREG_STAT1);
+	if ((status & (1 << MDIO_MMDREG_STAT1_FAULT_LBN)) != 0) {
+		if (fault_fatal) {
+			EFX_ERR(efx, "PHY MMD %d reporting fatal"
+				" fault: status %x\n", mmd, status);
+			return -EIO;
+		} else {
+			EFX_LOG(efx, "PHY MMD %d reporting status"
+				" %x (expected)\n", mmd, status);
+		}
+	}
+	return 0;
+}
+
+/* This ought to be ridiculous overkill. We expect it to fail rarely */
+#define MDIO45_RESET_TIME	1000 /* ms */
+#define MDIO45_RESET_ITERS	100
+
+int mdio_clause45_wait_reset_mmds(struct efx_nic *efx,
+				  unsigned int mmd_mask)
+{
+	const int spintime = MDIO45_RESET_TIME / MDIO45_RESET_ITERS;
+	int tries = MDIO45_RESET_ITERS;
+	int rc = 0;
+	int in_reset;
+
+	while (tries) {
+		int mask = mmd_mask;
+		int mmd = 0;
+		int stat;
+		in_reset = 0;
+		while (mask) {
+			if (mask & 1) {
+				stat = mdio_clause45_read(efx,
+							  efx->mii.phy_id,
+							  mmd,
+							  MDIO_MMDREG_CTRL1);
+				if (stat < 0) {
+					EFX_ERR(efx, "failed to read status of"
+						" MMD %d\n", mmd);
+					return -EIO;
+				}
+				if (stat & (1 << MDIO_MMDREG_CTRL1_RESET_LBN))
+					in_reset |= (1 << mmd);
+			}
+			mask = mask >> 1;
+			mmd++;
+		}
+		if (!in_reset)
+			break;
+		tries--;
+		msleep(spintime);
+	}
+	if (in_reset != 0) {
+		EFX_ERR(efx, "not all MMDs came out of reset in time."
+			" MMDs still in reset: %x\n", in_reset);
+		rc = -ETIMEDOUT;
+	}
+	return rc;
+}
+
+int mdio_clause45_check_mmds(struct efx_nic *efx,
+			     unsigned int mmd_mask, unsigned int fatal_mask)
+{
+	int devices, mmd = 0;
+	int probe_mmd;
+
+	/* Historically we have probed the PHYXS to find out what devices are
+	 * present,but that doesn't work so well if the PHYXS isn't expected
+	 * to exist, if so just find the first item in the list supplied. */
+	probe_mmd = (mmd_mask & MDIO_MMDREG_DEVS0_PHYXS) ? MDIO_MMD_PHYXS :
+	    __ffs(mmd_mask);
+	devices = mdio_clause45_read(efx, efx->mii.phy_id,
+				     probe_mmd, MDIO_MMDREG_DEVS0);
+
+	/* Check all the expected MMDs are present */
+	if (devices < 0) {
+		EFX_ERR(efx, "failed to read devices present\n");
+		return -EIO;
+	}
+	if ((devices & mmd_mask) != mmd_mask) {
+		EFX_ERR(efx, "required MMDs not present: got %x, "
+			"wanted %x\n", devices, mmd_mask);
+		return -ENODEV;
+	}
+	EFX_TRACE(efx, "Devices present: %x\n", devices);
+
+	/* Check all required MMDs are responding and happy. */
+	while (mmd_mask) {
+		if (mmd_mask & 1) {
+			int fault_fatal = fatal_mask & 1;
+			if (mdio_clause45_check_mmd(efx, mmd, fault_fatal))
+				return -EIO;
+		}
+		mmd_mask = mmd_mask >> 1;
+		fatal_mask = fatal_mask >> 1;
+		mmd++;
+	}
+
+	return 0;
+}
+
+int mdio_clause45_links_ok(struct efx_nic *efx, unsigned int mmd_mask)
+{
+	int phy_id = efx->mii.phy_id;
+	int status;
+	int ok = 1;
+	int mmd = 0;
+	int good;
+
+	while (mmd_mask) {
+		if (mmd_mask & 1) {
+			/* Double reads because link state is latched, and a
+			 * read moves the current state into the register */
+			status = mdio_clause45_read(efx, phy_id,
+						    mmd, MDIO_MMDREG_STAT1);
+			status = mdio_clause45_read(efx, phy_id,
+						    mmd, MDIO_MMDREG_STAT1);
+
+			good = status & (1 << MDIO_MMDREG_STAT1_LINK_LBN);
+			ok = ok && good;
+		}
+		mmd_mask = (mmd_mask >> 1);
+		mmd++;
+	}
+	return ok;
+}
+
+/**
+ * mdio_clause45_get_settings - Read (some of) the PHY settings over MDIO.
+ * @efx:		Efx NIC
+ * @ecmd: 		Buffer for settings
+ *
+ * On return the 'port', 'speed', 'supported' and 'advertising' fields of
+ * ecmd have been filled out based on the PMA type.
+ */
+void mdio_clause45_get_settings(struct efx_nic *efx,
+				struct ethtool_cmd *ecmd)
+{
+	int pma_type;
+
+	/* If no PMA is present we are presumably talking something XAUI-ish
+	 * like CX4. Which we report as FIBRE (see below) */
+	if ((efx->phy_op->mmds & DEV_PRESENT_BIT(MDIO_MMD_PMAPMD)) == 0) {
+		ecmd->speed = SPEED_10000;
+		ecmd->port = PORT_FIBRE;
+		ecmd->supported = SUPPORTED_FIBRE;
+		ecmd->advertising = ADVERTISED_FIBRE;
+		return;
+	}
+
+	pma_type = mdio_clause45_read(efx, efx->mii.phy_id,
+				      MDIO_MMD_PMAPMD, MDIO_MMDREG_CTRL2);
+	pma_type &= MDIO_PMAPMD_CTRL2_TYPE_MASK;
+
+	switch (pma_type) {
+		/* We represent CX4 as fibre in the absence of anything
+		   better. */
+	case MDIO_PMAPMD_CTRL2_10G_CX4:
+		ecmd->speed = SPEED_10000;
+		ecmd->port = PORT_FIBRE;
+		ecmd->supported = SUPPORTED_FIBRE;
+		ecmd->advertising = ADVERTISED_FIBRE;
+		break;
+		/* 10G Base-T */
+	case MDIO_PMAPMD_CTRL2_10G_BT:
+		ecmd->speed = SPEED_10000;
+		ecmd->port = PORT_TP;
+		ecmd->supported = SUPPORTED_TP | SUPPORTED_10000baseT_Full;
+		ecmd->advertising = (ADVERTISED_FIBRE
+				     | ADVERTISED_10000baseT_Full);
+		break;
+	case MDIO_PMAPMD_CTRL2_1G_BT:
+		ecmd->speed = SPEED_1000;
+		ecmd->port = PORT_TP;
+		ecmd->supported = SUPPORTED_TP | SUPPORTED_1000baseT_Full;
+		ecmd->advertising = (ADVERTISED_FIBRE
+				     | ADVERTISED_1000baseT_Full);
+		break;
+	case MDIO_PMAPMD_CTRL2_100_BT:
+		ecmd->speed = SPEED_100;
+		ecmd->port = PORT_TP;
+		ecmd->supported = SUPPORTED_TP | SUPPORTED_100baseT_Full;
+		ecmd->advertising = (ADVERTISED_FIBRE
+				     | ADVERTISED_100baseT_Full);
+		break;
+	case MDIO_PMAPMD_CTRL2_10_BT:
+		ecmd->speed = SPEED_10;
+		ecmd->port = PORT_TP;
+		ecmd->supported = SUPPORTED_TP | SUPPORTED_10baseT_Full;
+		ecmd->advertising = ADVERTISED_FIBRE | ADVERTISED_10baseT_Full;
+		break;
+	/* All the other defined modes are flavours of
+	 * 10G optical */
+	default:
+		ecmd->speed = SPEED_10000;
+		ecmd->port = PORT_FIBRE;
+		ecmd->supported = SUPPORTED_FIBRE;
+		ecmd->advertising = ADVERTISED_FIBRE;
+		break;
+	}
+}
+
+/**
+ * mdio_clause45_set_settings - Set (some of) the PHY settings over MDIO.
+ * @efx:		Efx NIC
+ * @ecmd: 		New settings
+ *
+ * Currently this just enforces that we are _not_ changing the
+ * 'port', 'speed', 'supported' or 'advertising' settings as these
+ * cannot be changed on any currently supported PHY.
+ */
+int mdio_clause45_set_settings(struct efx_nic *efx,
+			       struct ethtool_cmd *ecmd)
+{
+	struct ethtool_cmd tmpcmd;
+	mdio_clause45_get_settings(efx, &tmpcmd);
+	/* None of the current PHYs support more than one mode
+	 * of operation (and only 10GBT ever will), so keep things
+	 * simple for now */
+	if ((ecmd->speed == tmpcmd.speed) && (ecmd->port == tmpcmd.port) &&
+	    (ecmd->supported == tmpcmd.supported) &&
+	    (ecmd->advertising == tmpcmd.advertising))
+		return 0;
+	return -EOPNOTSUPP;
+}