+/* Generic function which updates the speed and duplex. If
+ * autonegotiation is enabled, it uses the AND of the link
+ * partner's advertised capabilities and our advertised
+ * capabilities. If autonegotiation is disabled, we use the
+ * appropriate bits in the control register.
+ *
+ * Stolen from Linux's mii.c and phy_device.c
+ */
+uint mii_parse_link(uint mii_reg, struct tsec_private *priv)
+{
+ /* We're using autonegotiation */
+ if (mii_reg & PHY_BMSR_AUTN_ABLE) {
+ uint lpa = 0;
+ uint gblpa = 0;
+
+ /* Check for gigabit capability */
+ if (mii_reg & PHY_BMSR_EXT) {
+ /* We want a list of states supported by
+ * both PHYs in the link
+ */
+ gblpa = read_phy_reg(priv, PHY_1000BTSR);
+ gblpa &= read_phy_reg(priv, PHY_1000BTCR) << 2;
+ }
+
+ /* Set the baseline so we only have to set them
+ * if they're different
+ */
+ priv->speed = 10;
+ priv->duplexity = 0;
+
+ /* Check the gigabit fields */
+ if (gblpa & (PHY_1000BTSR_1000FD | PHY_1000BTSR_1000HD)) {
+ priv->speed = 1000;
+
+ if (gblpa & PHY_1000BTSR_1000FD)
+ priv->duplexity = 1;
+
+ /* We're done! */
+ return 0;
+ }
+
+ lpa = read_phy_reg(priv, PHY_ANAR);
+ lpa &= read_phy_reg(priv, PHY_ANLPAR);
+
+ if (lpa & (PHY_ANLPAR_TXFD | PHY_ANLPAR_TX)) {
+ priv->speed = 100;
+
+ if (lpa & PHY_ANLPAR_TXFD)
+ priv->duplexity = 1;
+
+ } else if (lpa & PHY_ANLPAR_10FD)
+ priv->duplexity = 1;
+ } else {
+ uint bmcr = read_phy_reg(priv, PHY_BMCR);
+
+ priv->speed = 10;
+ priv->duplexity = 0;
+
+ if (bmcr & PHY_BMCR_DPLX)
+ priv->duplexity = 1;
+
+ if (bmcr & PHY_BMCR_1000_MBPS)
+ priv->speed = 1000;
+ else if (bmcr & PHY_BMCR_100_MBPS)
+ priv->speed = 100;
+ }
+
+ return 0;
+}
+