[PATCH V2 08/12] net-next: mediatek: add support for mt7620

[John Crispin]

Add support for SoCs from the mt7620 family. These all have one dedicated
external gbit port and a builtin 5 port 100mbit switch. Additionally one
of the 5 switch ports can be changed to become an additional gbit port
that we can attach a phy to. MT7620 was the first SoC released after
Ralink was acquired by MTK and has seen a lot of changes to the core.

With MT7620 we have seen the addition of some advanced features such as
TX vlan offloading, RX scatter gather and TSO. Newer MTK SoCs are based on
this design.

Although the builtin MT7530 is gbit capable, the builtin PHYs are only
100mbit. There are boards in the wild that use one of the gbit MACs to
attach an external MT7530. For this to work a few hacks need to be applied
to reorganize the MDIO address mappings and autopolling for the SoC to
correctly work with the external switch. This is however not part of the
series and will be part of a later series once we evaluated if we want to
use DSA or switchdev.

Signed-off-by: John Crispin <blogic@xxxxxxxxxxx>
Signed-off-by: Felix Fietkau <nbd@xxxxxxxxxxx>
Signed-off-by: Michael Lee <igvtee@xxxxxxxxx>
---
 drivers/net/ethernet/mediatek/mdio_mt7620.c |  168 +++++++++++++++
 drivers/net/ethernet/mediatek/soc_mt7620.c  |  296 +++++++++++++++++++++++++++
 2 files changed, 464 insertions(+)
 create mode 100644 drivers/net/ethernet/mediatek/mdio_mt7620.c
 create mode 100644 drivers/net/ethernet/mediatek/soc_mt7620.c

diff --git a/drivers/net/ethernet/mediatek/mdio_mt7620.c b/drivers/net/ethernet/mediatek/mdio_mt7620.c
new file mode 100644
index 0000000..b9e0eb2
--- /dev/null
+++ b/drivers/net/ethernet/mediatek/mdio_mt7620.c
@@ -0,0 +1,168 @@
+/*   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; version 2 of the License
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   Copyright (C) 2009-2016 John Crispin <blogic@xxxxxxxxxxx>
+ *   Copyright (C) 2009-2016 Felix Fietkau <nbd@xxxxxxxxxxx>
+ *   Copyright (C) 2013-2016 Michael Lee <igvtee@xxxxxxxxx>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+#include "mtk_eth_soc.h"
+#include "gsw_mt7620.h"
+#include "mdio.h"
+
+static int mt7620_mii_busy_wait(struct mt7620_gsw *gsw)
+{
+	unsigned long t_start = jiffies;
+
+	while (1) {
+		if (!(mtk_switch_r32(gsw,
+				     gsw->piac_offset + MT7620_GSW_REG_PIAC) &
+				     GSW_MDIO_ACCESS))
+			return 0;
+		if (time_after(jiffies, t_start + GSW_REG_PHY_TIMEOUT))
+			break;
+	}
+
+	dev_err(gsw->dev, "mdio: MDIO timeout\n");
+	return -1;
+}
+
+u32 _mt7620_mii_write(struct mt7620_gsw *gsw, u32 phy_addr,
+		      u32 phy_register, u32 write_data)
+{
+	if (mt7620_mii_busy_wait(gsw))
+		return -1;
+
+	write_data &= 0xffff;
+
+	mtk_switch_w32(gsw, GSW_MDIO_ACCESS | GSW_MDIO_START | GSW_MDIO_WRITE |
+		(phy_register << GSW_MDIO_REG_SHIFT) |
+		(phy_addr << GSW_MDIO_ADDR_SHIFT) | write_data,
+		MT7620_GSW_REG_PIAC);
+
+	if (mt7620_mii_busy_wait(gsw))
+		return -1;
+
+	return 0;
+}
+
+u32 _mt7620_mii_read(struct mt7620_gsw *gsw, int phy_addr, int phy_reg)
+{
+	u32 d;
+
+	if (mt7620_mii_busy_wait(gsw))
+		return 0xffff;
+
+	mtk_switch_w32(gsw, GSW_MDIO_ACCESS | GSW_MDIO_START | GSW_MDIO_READ |
+		(phy_reg << GSW_MDIO_REG_SHIFT) |
+		(phy_addr << GSW_MDIO_ADDR_SHIFT),
+		MT7620_GSW_REG_PIAC);
+
+	if (mt7620_mii_busy_wait(gsw))
+		return 0xffff;
+
+	d = mtk_switch_r32(gsw, MT7620_GSW_REG_PIAC) & 0xffff;
+
+	return d;
+}
+
+int mt7620_mdio_write(struct mii_bus *bus, int phy_addr, int phy_reg, u16 val)
+{
+	struct mtk_eth *eth = bus->priv;
+	struct mt7620_gsw *gsw = (struct mt7620_gsw *)eth->sw_priv;
+
+	return _mt7620_mii_write(gsw, phy_addr, phy_reg, val);
+}
+
+int mt7620_mdio_read(struct mii_bus *bus, int phy_addr, int phy_reg)
+{
+	struct mtk_eth *eth = bus->priv;
+	struct mt7620_gsw *gsw = (struct mt7620_gsw *)eth->sw_priv;
+
+	return _mt7620_mii_read(gsw, phy_addr, phy_reg);
+}
+
+void mt7530_mdio_w32(struct mt7620_gsw *gsw, u32 reg, u32 val)
+{
+	_mt7620_mii_write(gsw, 0x1f, 0x1f, (reg >> 6) & 0x3ff);
+	_mt7620_mii_write(gsw, 0x1f, (reg >> 2) & 0xf,  val & 0xffff);
+	_mt7620_mii_write(gsw, 0x1f, 0x10, val >> 16);
+}
+
+u32 mt7530_mdio_r32(struct mt7620_gsw *gsw, u32 reg)
+{
+	u16 high, low;
+
+	_mt7620_mii_write(gsw, 0x1f, 0x1f, (reg >> 6) & 0x3ff);
+	low = _mt7620_mii_read(gsw, 0x1f, (reg >> 2) & 0xf);
+	high = _mt7620_mii_read(gsw, 0x1f, 0x10);
+
+	return (high << 16) | (low & 0xffff);
+}
+
+void mt7530_mdio_m32(struct mt7620_gsw *gsw, u32 mask, u32 set, u32 reg)
+{
+	u32 val = mt7530_mdio_r32(gsw, reg);
+
+	val &= mask;
+	val |= set;
+	mt7530_mdio_w32(gsw, reg, val);
+}
+
+static unsigned char *mtk_speed_str(int speed)
+{
+	switch (speed) {
+	case 2:
+	case SPEED_1000:
+		return "1000";
+	case 1:
+	case SPEED_100:
+		return "100";
+	case 0:
+	case SPEED_10:
+		return "10";
+	}
+
+	return "? ";
+}
+
+int mt7620_has_carrier(struct mtk_eth *eth)
+{
+	struct mt7620_gsw *gsw = (struct mt7620_gsw *)eth->sw_priv;
+	int i;
+
+	for (i = 0; i < GSW_PORT6; i++)
+		if (mtk_switch_r32(gsw, GSW_REG_PORT_STATUS(i)) & 0x1)
+			return 1;
+	return 0;
+}
+
+void mt7620_print_link_state(struct mtk_eth *eth, int port, int link,
+			     int speed, int duplex)
+{
+	struct mt7620_gsw *gsw = eth->sw_priv;
+
+	if (link)
+		dev_info(gsw->dev, "port %d link up (%sMbps/%s duplex)\n",
+			 port, mtk_speed_str(speed),
+			 (duplex) ? "Full" : "Half");
+	else
+		dev_info(gsw->dev, "port %d link down\n", port);
+}
+
+void mt7620_mdio_link_adjust(struct mtk_eth *eth, int port)
+{
+	mt7620_print_link_state(eth, port, eth->link[port],
+				eth->phy->speed[port],
+				(eth->phy->duplex[port] == DUPLEX_FULL));
+}
diff --git a/drivers/net/ethernet/mediatek/soc_mt7620.c b/drivers/net/ethernet/mediatek/soc_mt7620.c
new file mode 100644
index 0000000..faf2a84
--- /dev/null
+++ b/drivers/net/ethernet/mediatek/soc_mt7620.c
@@ -0,0 +1,296 @@
+/*   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; version 2 of the License
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   Copyright (C) 2009-2016 John Crispin <blogic@xxxxxxxxxxx>
+ *   Copyright (C) 2009-2016 Felix Fietkau <nbd@xxxxxxxxxxx>
+ *   Copyright (C) 2013-2016 Michael Lee <igvtee@xxxxxxxxx>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/if_vlan.h>
+#include <linux/of_net.h>
+
+#include <asm/mach-ralink/ralink_regs.h>
+
+#include <mt7620.h>
+#include "mtk_eth_soc.h"
+#include "gsw_mt7620.h"
+#include "mdio.h"
+
+#define MT7620_CDMA_CSG_CFG	0x400
+#define MT7620_DMA_VID		(MT7620_CDMA_CSG_CFG + 0x30)
+#define MT7620_RESET_FE		BIT(21)
+#define MT7620_RESET_ESW	BIT(23)
+#define MT7620_L4_VALID		BIT(23)
+
+#define MT7620_TX_DMA_UDF	BIT(15)
+#define TX_DMA_FP_BMAP		((0xff) << 19)
+
+#define CDMA_ICS_EN		BIT(2)
+#define CDMA_UCS_EN		BIT(1)
+#define CDMA_TCS_EN		BIT(0)
+
+#define GDMA_ICS_EN		BIT(22)
+#define GDMA_TCS_EN		BIT(21)
+#define GDMA_UCS_EN		BIT(20)
+#define	GDMA_FRC_P_MASK		0x07
+
+/* frame engine counters */
+#define MT7620_REG_MIB_OFFSET	0x1000
+#define MT7620_PPE_AC_BCNT0	(MT7620_REG_MIB_OFFSET + 0x00)
+#define MT7620_GDM1_TX_GBCNT	(MT7620_REG_MIB_OFFSET + 0x300)
+#define MT7620_GDM2_TX_GBCNT	(MT7620_GDM1_TX_GBCNT + 0x40)
+
+#define GSW_REG_GDMA1_MAC_ADRL	0x508
+#define GSW_REG_GDMA1_MAC_ADRH	0x50C
+
+#define MT7620_MTK_RST_GL	0x04
+#define MT7620_MTK_INT_STATUS2	0x08
+
+/* MTK_INT_STATUS reg on mt7620 define CNT_GDM1_AF at BIT(29)
+ * but after test it should be BIT(13).
+ */
+#define MT7620_MTK_GDM1_AF	BIT(13)
+
+static const u16 mt7620_reg_table[MTK_REG_COUNT] = {
+	[MTK_REG_PDMA_GLO_CFG] = RT5350_PDMA_GLO_CFG,
+	[MTK_REG_PDMA_RST_CFG] = RT5350_PDMA_RST_CFG,
+	[MTK_REG_DLY_INT_CFG] = RT5350_DLY_INT_CFG,
+	[MTK_REG_TX_BASE_PTR0] = RT5350_TX_BASE_PTR0,
+	[MTK_REG_TX_MAX_CNT0] = RT5350_TX_MAX_CNT0,
+	[MTK_REG_TX_CTX_IDX0] = RT5350_TX_CTX_IDX0,
+	[MTK_REG_TX_DTX_IDX0] = RT5350_TX_DTX_IDX0,
+	[MTK_REG_RX_BASE_PTR0] = RT5350_RX_BASE_PTR0,
+	[MTK_REG_RX_MAX_CNT0] = RT5350_RX_MAX_CNT0,
+	[MTK_REG_RX_CALC_IDX0] = RT5350_RX_CALC_IDX0,
+	[MTK_REG_RX_DRX_IDX0] = RT5350_RX_DRX_IDX0,
+	[MTK_REG_MTK_INT_ENABLE] = RT5350_MTK_INT_ENABLE,
+	[MTK_REG_MTK_INT_STATUS] = RT5350_MTK_INT_STATUS,
+	[MTK_REG_MTK_DMA_VID_BASE] = MT7620_DMA_VID,
+	[MTK_REG_MTK_COUNTER_BASE] = MT7620_GDM1_TX_GBCNT,
+	[MTK_REG_MTK_RST_GL] = MT7620_MTK_RST_GL,
+	[MTK_REG_MTK_INT_STATUS2] = MT7620_MTK_INT_STATUS2,
+};
+
+static void mt7620_set_mac(struct mtk_mac *mac, unsigned char *hwaddr)
+{
+	struct mt7620_gsw *gsw = (struct mt7620_gsw *)mac->hw->sw_priv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&mac->hw->page_lock, flags);
+	mtk_switch_w32(gsw, (hwaddr[0] << 8) | hwaddr[1], GSW_REG_SMACCR1);
+	mtk_switch_w32(gsw, (hwaddr[2] << 24) | (hwaddr[3] << 16) |
+			    (hwaddr[4] << 8) | hwaddr[5],
+		       GSW_REG_SMACCR0);
+	spin_unlock_irqrestore(&mac->hw->page_lock, flags);
+}
+
+/* figure out which is the lowest and highest phy connected and enable
+ * autopolling for those phys
+ */
+static void mt7620_auto_poll(struct mt7620_gsw *gsw)
+{
+	int phy;
+	int lsb = -1, msb = 0;
+
+	for_each_set_bit(phy, &gsw->autopoll, 32) {
+		if (lsb < 0)
+			lsb = phy;
+		msb = phy;
+	}
+
+	if (lsb == msb)
+		lsb--;
+
+	mtk_switch_w32(gsw, PHY_AN_EN | PHY_PRE_EN | PMY_MDC_CONF(5) |
+		(msb << 8) | lsb, MT7620_ESW_PHY_POLLING);
+}
+
+static void mt7620_port_init(struct mtk_eth *eth, struct mtk_mac *mac,
+			     struct device_node *np)
+{
+	struct mt7620_gsw *gsw = (struct mt7620_gsw *)eth->sw_priv;
+	const __be32 *_id = of_get_property(np, "reg", NULL);
+	int phy_mode, size, id;
+	int shift = 12;
+	u32 val, mask = 0;
+	int min = (gsw->port4 == PORT4_EPHY) ? (5) : (4);
+
+	if (!_id || (be32_to_cpu(*_id) < min) || (be32_to_cpu(*_id) > 5)) {
+		if (_id)
+			pr_err("%s: invalid port id %d\n", np->name,
+			       be32_to_cpu(*_id));
+		else
+			pr_err("%s: invalid port id\n", np->name);
+		return;
+	}
+
+	id = be32_to_cpu(*_id);
+
+	if (id == 4)
+		shift = 14;
+
+	eth->phy->phy_fixed[id] = of_get_property(np, "mediatek,fixed-link",
+						   &size);
+	if (eth->phy->phy_fixed[id] &&
+	    (size != (4 * sizeof(*eth->phy->phy_fixed[id])))) {
+		pr_err("%s: invalid fixed link property\n", np->name);
+		eth->phy->phy_fixed[id] = NULL;
+		return;
+	}
+
+	phy_mode = of_get_phy_mode(np);
+	switch (phy_mode) {
+	case PHY_INTERFACE_MODE_RGMII:
+		mask = 0;
+		break;
+	case PHY_INTERFACE_MODE_MII:
+		mask = 1;
+		break;
+	case PHY_INTERFACE_MODE_RMII:
+		mask = 2;
+		break;
+	default:
+		dev_err(eth->dev, "port %d - invalid phy mode\n", id);
+		return;
+	}
+
+	eth->phy->phy_node[id] = of_parse_phandle(np, "phy-handle", 0);
+	if (!eth->phy->phy_node[id] && !eth->phy->phy_fixed[id])
+		return;
+
+	val = rt_sysc_r32(SYSC_REG_CFG1);
+	val &= ~(3 << shift);
+	val |= mask << shift;
+	rt_sysc_w32(val, SYSC_REG_CFG1);
+
+	if (eth->phy->phy_fixed[id]) {
+		const __be32 *link = eth->phy->phy_fixed[id];
+		int tx_fc, rx_fc;
+		u32 val = 0;
+
+		eth->phy->speed[id] = be32_to_cpup(link++);
+		tx_fc = be32_to_cpup(link++);
+		rx_fc = be32_to_cpup(link++);
+		eth->phy->duplex[id] = be32_to_cpup(link++);
+		eth->link[id] = 1;
+
+		switch (eth->phy->speed[id]) {
+		case SPEED_10:
+			val = 0;
+			break;
+		case SPEED_100:
+			val = 1;
+			break;
+		case SPEED_1000:
+			val = 2;
+			break;
+		default:
+			dev_err(eth->dev, "invalid link speed: %d\n",
+				eth->phy->speed[id]);
+			eth->phy->phy_fixed[id] = 0;
+			return;
+		}
+		val = PMCR_SPEED(val);
+		val |= PMCR_LINK | PMCR_BACKPRES | PMCR_BACKOFF | PMCR_RX_EN |
+			PMCR_TX_EN | PMCR_FORCE | PMCR_MAC_MODE | PMCR_IPG;
+		if (tx_fc)
+			val |= PMCR_TX_FC;
+		if (rx_fc)
+			val |= PMCR_RX_FC;
+		if (eth->phy->duplex[id])
+			val |= PMCR_DUPLEX;
+		mtk_switch_w32(gsw, val, GSW_REG_PORT_PMCR(id));
+		dev_info(eth->dev, "using fixed link parameters\n");
+		return;
+	}
+
+	if (eth->phy->phy_node[id] && eth->mii_bus->phy_map[id]) {
+		u32 val = PMCR_BACKPRES | PMCR_BACKOFF | PMCR_RX_EN |
+			PMCR_TX_EN |  PMCR_MAC_MODE | PMCR_IPG;
+
+		mtk_switch_w32(gsw, val, GSW_REG_PORT_PMCR(id));
+		mtk_connect_phy_node(eth, mac, eth->phy->phy_node[id]);
+		gsw->autopoll |= BIT(id);
+		mt7620_auto_poll(gsw);
+		return;
+	}
+}
+
+static void mt7620_mtk_reset(struct mtk_eth *eth)
+{
+	mtk_reset(eth, MT7620_RESET_FE | MT7620_RESET_ESW);
+}
+
+static int mt7620_fwd_config(struct mtk_eth *eth)
+{
+	/* Make sure that the CPU port is used as the mac destination port */
+	mtk_w32(eth, mtk_r32(eth, MT7620_GDMA1_FWD_CFG) & ~GDMA_FRC_P_MASK,
+		MT7620_GDMA1_FWD_CFG);
+
+	/* Enable TX Checksum Offloading */
+	mtk_w32(eth,
+		mtk_r32(eth, MT7620_GDMA1_FWD_CFG) |
+		(GDMA_ICS_EN | GDMA_TCS_EN | GDMA_UCS_EN),
+		MT7620_GDMA1_FWD_CFG);
+
+	/* Enable RX Checksum Offloading */
+	mtk_w32(eth,
+		mtk_r32(eth, MT7620_CDMA_CSG_CFG) |
+		(CDMA_ICS_EN | CDMA_UCS_EN | CDMA_TCS_EN),
+		MT7620_CDMA_CSG_CFG);
+
+	return 0;
+}
+
+static void mt7620_init_data(struct mtk_soc_data *data,
+			     struct net_device *netdev)
+{
+	if (mt7620_get_eco() >= 5)
+		netdev->hw_features |= NETIF_F_SG | NETIF_F_TSO | NETIF_F_TSO6 |
+			NETIF_F_IPV6_CSUM;
+}
+
+static struct mtk_soc_data mt7620_data = {
+	.hw_features = NETIF_F_IP_CSUM | NETIF_F_RXCSUM |
+		       NETIF_F_HW_VLAN_CTAG_TX,
+	.dma_type = MTK_PDMA,
+	.dma_ring_size = 256,
+	.napi_weight = 64,
+	.piac_offset = 0x7000,
+	.padding_64b = 1,
+	.rx_2b_offset = 1,
+	.rx_sg_dma = 1,
+	.has_switch = 1,
+	.mac_count = 1,
+	.init_data = mt7620_init_data,
+	.reset_fe = mt7620_mtk_reset,
+	.set_mac = mt7620_set_mac,
+	.fwd_config = mt7620_fwd_config,
+	.switch_init = mtk_gsw_init,
+	.port_init = mt7620_port_init,
+	.reg_table = mt7620_reg_table,
+	.pdma_glo_cfg = MTK_PDMA_SIZE_16DWORDS,
+	.rx_int = RT5350_RX_DONE_INT,
+	.tx_int = RT5350_TX_DONE_INT,
+	.status_int = MT7620_MTK_GDM1_AF,
+	.checksum_bit = MT7620_L4_VALID,
+	.has_carrier = mt7620_has_carrier,
+	.mdio_read = mt7620_mdio_read,
+	.mdio_write = mt7620_mdio_write,
+	.mdio_adjust_link = mt7620_mdio_link_adjust,
+};
+
+const struct of_device_id of_mtk_match[] = {
+	{ .compatible = "mediatek,mt7620-eth", .data = &mt7620_data },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, of_mtk_match);
-- 
1.7.10.4