net: dsa: ocelot: add driver for Felix switch family

This supports an Ethernet switching core from Vitesse / Microsemi /
Microchip (VSC9959) which is part of the Ocelot family (a brand name),
and whose code name is Felix. The switch can be (and is) integrated on
different SoCs as a PCIe endpoint device.

The functionality is provided by the core of the Ocelot switch driver
(drivers/net/ethernet/mscc). In this regard, the current driver is an
instance of Microsemi's Ocelot core driver, with a DSA front-end. It
inherits its name from VSC9959's code name, to distinguish itself from
the switchdev ocelot driver.

The patch adds the logic for probing a PCI device and defines the
register map for the VSC9959 switch core, since it has some differences
in register addresses and bitfield mappings compared to the other Ocelot
switches (VSC7511, VSC7512, VSC7513, VSC7514).

The Felix driver declares the register map as part of the "instance
table". Currently the VSC9959 inside NXP LS1028A is the only instance,
but presumably it can support other switches in the Ocelot family, when
used in DSA mode (Linux running on the external CPU, and not on the
embedded MIPS).

In a few cases, some h/w operations have to be done differently on
VSC9959 due to missing bitfields.  This is the case for the switch core
reset and init.  Because for this operation Ocelot uses some bits that
are not present on Felix, the latter has to use a register from the
global registers block (GCB) instead.

Although it is a PCI driver, it relies on DT bindings for compatibility
with DSA (CPU port link, PHY library). It does not have any custom
device tree bindings, since we would like to minimize its dependency on
device tree though.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 441 insertions, 0 deletions

diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c
new file mode 100644
index 000000000000..05e3f2898bf6
--- /dev/null
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -0,0 +1,441 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2019 NXP Semiconductors
+ */
+#include <uapi/linux/if_bridge.h>
+#include <soc/mscc/ocelot.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/of.h>
+#include <net/dsa.h>
+#include "felix.h"
+
+static enum dsa_tag_protocol felix_get_tag_protocol(struct dsa_switch *ds,
+						    int port)
+{
+	return DSA_TAG_PROTO_OCELOT;
+}
+
+static int felix_set_ageing_time(struct dsa_switch *ds,
+				 unsigned int ageing_time)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_set_ageing_time(ocelot, ageing_time);
+
+	return 0;
+}
+
+static void felix_adjust_link(struct dsa_switch *ds, int port,
+			      struct phy_device *phydev)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_adjust_link(ocelot, port, phydev);
+}
+
+static int felix_fdb_dump(struct dsa_switch *ds, int port,
+			  dsa_fdb_dump_cb_t *cb, void *data)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_fdb_dump(ocelot, port, cb, data);
+}
+
+static int felix_fdb_add(struct dsa_switch *ds, int port,
+			 const unsigned char *addr, u16 vid)
+{
+	struct ocelot *ocelot = ds->priv;
+	bool vlan_aware;
+
+	vlan_aware = dsa_port_is_vlan_filtering(dsa_to_port(ds, port));
+
+	return ocelot_fdb_add(ocelot, port, addr, vid, vlan_aware);
+}
+
+static int felix_fdb_del(struct dsa_switch *ds, int port,
+			 const unsigned char *addr, u16 vid)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_fdb_del(ocelot, port, addr, vid);
+}
+
+static void felix_bridge_stp_state_set(struct dsa_switch *ds, int port,
+				       u8 state)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_bridge_stp_state_set(ocelot, port, state);
+}
+
+static int felix_bridge_join(struct dsa_switch *ds, int port,
+			     struct net_device *br)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_port_bridge_join(ocelot, port, br);
+}
+
+static void felix_bridge_leave(struct dsa_switch *ds, int port,
+			       struct net_device *br)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_port_bridge_leave(ocelot, port, br);
+}
+
+/* This callback needs to be present */
+static int felix_vlan_prepare(struct dsa_switch *ds, int port,
+			      const struct switchdev_obj_port_vlan *vlan)
+{
+	return 0;
+}
+
+static int felix_vlan_filtering(struct dsa_switch *ds, int port, bool enabled)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_port_vlan_filtering(ocelot, port, enabled);
+
+	return 0;
+}
+
+static void felix_vlan_add(struct dsa_switch *ds, int port,
+			   const struct switchdev_obj_port_vlan *vlan)
+{
+	struct ocelot *ocelot = ds->priv;
+	u16 vid;
+	int err;
+
+	for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
+		err = ocelot_vlan_add(ocelot, port, vid,
+				      vlan->flags & BRIDGE_VLAN_INFO_PVID,
+				      vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED);
+		if (err) {
+			dev_err(ds->dev, "Failed to add VLAN %d to port %d: %d\n",
+				vid, port, err);
+			return;
+		}
+	}
+}
+
+static int felix_vlan_del(struct dsa_switch *ds, int port,
+			  const struct switchdev_obj_port_vlan *vlan)
+{
+	struct ocelot *ocelot = ds->priv;
+	u16 vid;
+	int err;
+
+	for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
+		err = ocelot_vlan_del(ocelot, port, vid);
+		if (err) {
+			dev_err(ds->dev, "Failed to remove VLAN %d from port %d: %d\n",
+				vid, port, err);
+			return err;
+		}
+	}
+	return 0;
+}
+
+static int felix_port_enable(struct dsa_switch *ds, int port,
+			     struct phy_device *phy)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_port_enable(ocelot, port, phy);
+
+	return 0;
+}
+
+static void felix_port_disable(struct dsa_switch *ds, int port)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_port_disable(ocelot, port);
+}
+
+static void felix_get_strings(struct dsa_switch *ds, int port,
+			      u32 stringset, u8 *data)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_get_strings(ocelot, port, stringset, data);
+}
+
+static void felix_get_ethtool_stats(struct dsa_switch *ds, int port, u64 *data)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	ocelot_get_ethtool_stats(ocelot, port, data);
+}
+
+static int felix_get_sset_count(struct dsa_switch *ds, int port, int sset)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_get_sset_count(ocelot, port, sset);
+}
+
+static int felix_get_ts_info(struct dsa_switch *ds, int port,
+			     struct ethtool_ts_info *info)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	return ocelot_get_ts_info(ocelot, port, info);
+}
+
+static int felix_init_structs(struct felix *felix, int num_phys_ports)
+{
+	struct ocelot *ocelot = &felix->ocelot;
+	resource_size_t base;
+	int port, i, err;
+
+	ocelot->num_phys_ports = num_phys_ports;
+	ocelot->ports = devm_kcalloc(ocelot->dev, num_phys_ports,
+				     sizeof(struct ocelot_port *), GFP_KERNEL);
+	if (!ocelot->ports)
+		return -ENOMEM;
+
+	ocelot->map		= felix->info->map;
+	ocelot->stats_layout	= felix->info->stats_layout;
+	ocelot->num_stats	= felix->info->num_stats;
+	ocelot->shared_queue_sz	= felix->info->shared_queue_sz;
+	ocelot->ops		= felix->info->ops;
+
+	base = pci_resource_start(felix->pdev, felix->info->pci_bar);
+
+	for (i = 0; i < TARGET_MAX; i++) {
+		struct regmap *target;
+		struct resource *res;
+
+		if (!felix->info->target_io_res[i].name)
+			continue;
+
+		res = &felix->info->target_io_res[i];
+		res->flags = IORESOURCE_MEM;
+		res->start += base;
+		res->end += base;
+
+		target = ocelot_regmap_init(ocelot, res);
+		if (IS_ERR(target)) {
+			dev_err(ocelot->dev,
+				"Failed to map device memory space\n");
+			return PTR_ERR(target);
+		}
+
+		ocelot->targets[i] = target;
+	}
+
+	err = ocelot_regfields_init(ocelot, felix->info->regfields);
+	if (err) {
+		dev_err(ocelot->dev, "failed to init reg fields map\n");
+		return err;
+	}
+
+	for (port = 0; port < num_phys_ports; port++) {
+		struct ocelot_port *ocelot_port;
+		void __iomem *port_regs;
+		struct resource *res;
+
+		ocelot_port = devm_kzalloc(ocelot->dev,
+					   sizeof(struct ocelot_port),
+					   GFP_KERNEL);
+		if (!ocelot_port) {
+			dev_err(ocelot->dev,
+				"failed to allocate port memory\n");
+			return -ENOMEM;
+		}
+
+		res = &felix->info->port_io_res[port];
+		res->flags = IORESOURCE_MEM;
+		res->start += base;
+		res->end += base;
+
+		port_regs = devm_ioremap_resource(ocelot->dev, res);
+		if (IS_ERR(port_regs)) {
+			dev_err(ocelot->dev,
+				"failed to map registers for port %d\n", port);
+			return PTR_ERR(port_regs);
+		}
+
+		ocelot_port->ocelot = ocelot;
+		ocelot_port->regs = port_regs;
+		ocelot->ports[port] = ocelot_port;
+	}
+
+	return 0;
+}
+
+/* Hardware initialization done here so that we can allocate structures with
+ * devm without fear of dsa_register_switch returning -EPROBE_DEFER and causing
+ * us to allocate structures twice (leak memory) and map PCI memory twice
+ * (which will not work).
+ */
+static int felix_setup(struct dsa_switch *ds)
+{
+	struct ocelot *ocelot = ds->priv;
+	struct felix *felix = ocelot_to_felix(ocelot);
+	int port, err;
+
+	err = felix_init_structs(felix, ds->num_ports);
+	if (err)
+		return err;
+
+	ocelot_init(ocelot);
+
+	for (port = 0; port < ds->num_ports; port++) {
+		ocelot_init_port(ocelot, port);
+
+		if (port == dsa_upstream_port(ds, port))
+			ocelot_set_cpu_port(ocelot, port,
+					    OCELOT_TAG_PREFIX_NONE,
+					    OCELOT_TAG_PREFIX_LONG);
+	}
+
+	return 0;
+}
+
+static void felix_teardown(struct dsa_switch *ds)
+{
+	struct ocelot *ocelot = ds->priv;
+
+	/* stop workqueue thread */
+	ocelot_deinit(ocelot);
+}
+
+static const struct dsa_switch_ops felix_switch_ops = {
+	.get_tag_protocol	= felix_get_tag_protocol,
+	.setup			= felix_setup,
+	.teardown		= felix_teardown,
+	.set_ageing_time	= felix_set_ageing_time,
+	.get_strings		= felix_get_strings,
+	.get_ethtool_stats	= felix_get_ethtool_stats,
+	.get_sset_count		= felix_get_sset_count,
+	.get_ts_info		= felix_get_ts_info,
+	.adjust_link		= felix_adjust_link,
+	.port_enable		= felix_port_enable,
+	.port_disable		= felix_port_disable,
+	.port_fdb_dump		= felix_fdb_dump,
+	.port_fdb_add		= felix_fdb_add,
+	.port_fdb_del		= felix_fdb_del,
+	.port_bridge_join	= felix_bridge_join,
+	.port_bridge_leave	= felix_bridge_leave,
+	.port_stp_state_set	= felix_bridge_stp_state_set,
+	.port_vlan_prepare	= felix_vlan_prepare,
+	.port_vlan_filtering	= felix_vlan_filtering,
+	.port_vlan_add		= felix_vlan_add,
+	.port_vlan_del		= felix_vlan_del,
+};
+
+static struct felix_info *felix_instance_tbl[] = {
+	[FELIX_INSTANCE_VSC9959] = &felix_info_vsc9959,
+};
+
+static int felix_pci_probe(struct pci_dev *pdev,
+			   const struct pci_device_id *id)
+{
+	enum felix_instance instance = id->driver_data;
+	struct dsa_switch *ds;
+	struct ocelot *ocelot;
+	struct felix *felix;
+	int err;
+
+	err = pci_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "device enable failed\n");
+		goto err_pci_enable;
+	}
+
+	/* set up for high or low dma */
+	err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (err) {
+		err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+		if (err) {
+			dev_err(&pdev->dev,
+				"DMA configuration failed: 0x%x\n", err);
+			goto err_dma;
+		}
+	}
+
+	felix = kzalloc(sizeof(struct felix), GFP_KERNEL);
+	if (!felix) {
+		err = -ENOMEM;
+		dev_err(&pdev->dev, "Failed to allocate driver memory\n");
+		goto err_alloc_felix;
+	}
+
+	pci_set_drvdata(pdev, felix);
+	ocelot = &felix->ocelot;
+	ocelot->dev = &pdev->dev;
+	felix->pdev = pdev;
+	felix->info = felix_instance_tbl[instance];
+
+	pci_set_master(pdev);
+
+	ds = kzalloc(sizeof(struct dsa_switch), GFP_KERNEL);
+	if (!ds) {
+		err = -ENOMEM;
+		dev_err(&pdev->dev, "Failed to allocate DSA switch\n");
+		goto err_alloc_ds;
+	}
+
+	ds->dev = &pdev->dev;
+	ds->num_ports = felix->info->num_ports;
+	ds->ops = &felix_switch_ops;
+	ds->priv = ocelot;
+	felix->ds = ds;
+
+	err = dsa_register_switch(ds);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to register DSA switch: %d\n", err);
+		goto err_register_ds;
+	}
+
+	return 0;
+
+err_register_ds:
+	kfree(ds);
+err_alloc_ds:
+err_alloc_felix:
+	kfree(felix);
+err_dma:
+	pci_disable_device(pdev);
+err_pci_enable:
+	return err;
+}
+
+static void felix_pci_remove(struct pci_dev *pdev)
+{
+	struct felix *felix;
+
+	felix = pci_get_drvdata(pdev);
+
+	dsa_unregister_switch(felix->ds);
+
+	kfree(felix->ds);
+	kfree(felix);
+
+	pci_disable_device(pdev);
+}
+
+static struct pci_device_id felix_ids[] = {
+	{
+		/* NXP LS1028A */
+		PCI_DEVICE(PCI_VENDOR_ID_FREESCALE, 0xEEF0),
+		.driver_data = FELIX_INSTANCE_VSC9959,
+	},
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, felix_ids);
+
+static struct pci_driver felix_pci_driver = {
+	.name		= KBUILD_MODNAME,
+	.id_table	= felix_ids,
+	.probe		= felix_pci_probe,
+	.remove		= felix_pci_remove,
+};
+
+module_pci_driver(felix_pci_driver);
+
+MODULE_DESCRIPTION("Felix Switch driver");
+MODULE_LICENSE("GPL v2");