v4.19.13 snapshot.
diff --git a/drivers/net/phy/swphy.c b/drivers/net/phy/swphy.c
new file mode 100644
index 0000000..34f58f2
--- /dev/null
+++ b/drivers/net/phy/swphy.c
@@ -0,0 +1,179 @@
+/*
+ * Software PHY emulation
+ *
+ * Code taken from fixed_phy.c by Russell King <rmk+kernel@arm.linux.org.uk>
+ *
+ * Author: Vitaly Bordug <vbordug@ru.mvista.com>
+ * Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * Copyright (c) 2006-2007 MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#include <linux/export.h>
+#include <linux/mii.h>
+#include <linux/phy.h>
+#include <linux/phy_fixed.h>
+
+#include "swphy.h"
+
+#define MII_REGS_NUM 29
+
+struct swmii_regs {
+ u16 bmcr;
+ u16 bmsr;
+ u16 lpa;
+ u16 lpagb;
+};
+
+enum {
+ SWMII_SPEED_10 = 0,
+ SWMII_SPEED_100,
+ SWMII_SPEED_1000,
+ SWMII_DUPLEX_HALF = 0,
+ SWMII_DUPLEX_FULL,
+};
+
+/*
+ * These two tables get bitwise-anded together to produce the final result.
+ * This means the speed table must contain both duplex settings, and the
+ * duplex table must contain all speed settings.
+ */
+static const struct swmii_regs speed[] = {
+ [SWMII_SPEED_10] = {
+ .bmcr = BMCR_FULLDPLX,
+ .lpa = LPA_10FULL | LPA_10HALF,
+ },
+ [SWMII_SPEED_100] = {
+ .bmcr = BMCR_FULLDPLX | BMCR_SPEED100,
+ .bmsr = BMSR_100FULL | BMSR_100HALF,
+ .lpa = LPA_100FULL | LPA_100HALF,
+ },
+ [SWMII_SPEED_1000] = {
+ .bmcr = BMCR_FULLDPLX | BMCR_SPEED1000,
+ .bmsr = BMSR_ESTATEN,
+ .lpagb = LPA_1000FULL | LPA_1000HALF,
+ },
+};
+
+static const struct swmii_regs duplex[] = {
+ [SWMII_DUPLEX_HALF] = {
+ .bmcr = ~BMCR_FULLDPLX,
+ .bmsr = BMSR_ESTATEN | BMSR_100HALF,
+ .lpa = LPA_10HALF | LPA_100HALF,
+ .lpagb = LPA_1000HALF,
+ },
+ [SWMII_DUPLEX_FULL] = {
+ .bmcr = ~0,
+ .bmsr = BMSR_ESTATEN | BMSR_100FULL,
+ .lpa = LPA_10FULL | LPA_100FULL,
+ .lpagb = LPA_1000FULL,
+ },
+};
+
+static int swphy_decode_speed(int speed)
+{
+ switch (speed) {
+ case 1000:
+ return SWMII_SPEED_1000;
+ case 100:
+ return SWMII_SPEED_100;
+ case 10:
+ return SWMII_SPEED_10;
+ default:
+ return -EINVAL;
+ }
+}
+
+/**
+ * swphy_validate_state - validate the software phy status
+ * @state: software phy status
+ *
+ * This checks that we can represent the state stored in @state can be
+ * represented in the emulated MII registers. Returns 0 if it can,
+ * otherwise returns -EINVAL.
+ */
+int swphy_validate_state(const struct fixed_phy_status *state)
+{
+ int err;
+
+ if (state->link) {
+ err = swphy_decode_speed(state->speed);
+ if (err < 0) {
+ pr_warn("swphy: unknown speed\n");
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(swphy_validate_state);
+
+/**
+ * swphy_read_reg - return a MII register from the fixed phy state
+ * @reg: MII register
+ * @state: fixed phy status
+ *
+ * Return the MII @reg register generated from the fixed phy state @state.
+ */
+int swphy_read_reg(int reg, const struct fixed_phy_status *state)
+{
+ int speed_index, duplex_index;
+ u16 bmsr = BMSR_ANEGCAPABLE;
+ u16 bmcr = 0;
+ u16 lpagb = 0;
+ u16 lpa = 0;
+
+ if (reg > MII_REGS_NUM)
+ return -1;
+
+ speed_index = swphy_decode_speed(state->speed);
+ if (WARN_ON(speed_index < 0))
+ return 0;
+
+ duplex_index = state->duplex ? SWMII_DUPLEX_FULL : SWMII_DUPLEX_HALF;
+
+ bmsr |= speed[speed_index].bmsr & duplex[duplex_index].bmsr;
+
+ if (state->link) {
+ bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
+
+ bmcr |= speed[speed_index].bmcr & duplex[duplex_index].bmcr;
+ lpa |= speed[speed_index].lpa & duplex[duplex_index].lpa;
+ lpagb |= speed[speed_index].lpagb & duplex[duplex_index].lpagb;
+
+ if (state->pause)
+ lpa |= LPA_PAUSE_CAP;
+
+ if (state->asym_pause)
+ lpa |= LPA_PAUSE_ASYM;
+ }
+
+ switch (reg) {
+ case MII_BMCR:
+ return bmcr;
+ case MII_BMSR:
+ return bmsr;
+ case MII_PHYSID1:
+ case MII_PHYSID2:
+ return 0;
+ case MII_LPA:
+ return lpa;
+ case MII_STAT1000:
+ return lpagb;
+
+ /*
+ * We do not support emulating Clause 45 over Clause 22 register
+ * reads. Return an error instead of bogus data.
+ */
+ case MII_MMD_CTRL:
+ case MII_MMD_DATA:
+ return -1;
+
+ default:
+ return 0xffff;
+ }
+}
+EXPORT_SYMBOL_GPL(swphy_read_reg);