2 files changed, 479 insertions, 0 deletions
diff --git a/net/Makefile b/net/Makefile
index 76527f7..fb3eba8 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_NET)      += arp.o
 obj-$(CONFIG_CMD_BOOTP) += bootp.o
 obj-$(CONFIG_CMD_CDP)  += cdp.o
 obj-$(CONFIG_CMD_DNS)  += dns.o
+obj-$(CONFIG_DM_DSA)   += dsa-uclass.o
 ifdef CONFIG_DM_ETH
 obj-$(CONFIG_NET)      += eth-uclass.o
 else
diff --git a/net/dsa-uclass.c b/net/dsa-uclass.c
new file mode 100644
index 0000000..2ce9ddb
--- /dev/null
+++ b/net/dsa-uclass.c
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2019-2021 NXP
+ */
+
+#include <net/dsa.h>
+#include <dm/lists.h>
+#include <dm/device_compat.h>
+#include <dm/device-internal.h>
+#include <dm/uclass-internal.h>
+#include <linux/bitmap.h>
+#include <miiphy.h>
+
+#define DSA_PORT_CHILD_DRV_NAME "dsa-port"
+
+/* per-device internal state structure */
+struct dsa_priv {
+	struct phy_device *cpu_port_fixed_phy;
+	struct udevice *master_dev;
+	int num_ports;
+	u32 cpu_port;
+	int headroom;
+	int tailroom;
+};
+
+/* external API */
+int dsa_set_tagging(struct udevice *dev, ushort headroom, ushort tailroom)
+{
+	struct dsa_priv *priv;
+
+	if (!dev || !dev_get_uclass_priv(dev))
+		return -ENODEV;
+
+	if (headroom + tailroom > DSA_MAX_OVR)
+		return -EINVAL;
+
+	priv = dev_get_uclass_priv(dev);
+
+	if (headroom > 0)
+		priv->headroom = headroom;
+	if (tailroom > 0)
+		priv->tailroom = tailroom;
+
+	return 0;
+}
+
+/* returns the DSA master Ethernet device */
+struct udevice *dsa_get_master(struct udevice *dev)
+{
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+
+	if (!priv)
+		return NULL;
+
+	return priv->master_dev;
+}
+
+/*
+ * Start the desired port, the CPU port and the master Eth interface.
+ * TODO: if cascaded we may need to _start ports in other switches too
+ */
+static int dsa_port_start(struct udevice *pdev)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+	struct udevice *master = dsa_get_master(dev);
+	struct dsa_ops *ops = dsa_get_ops(dev);
+	int err;
+
+	if (!priv)
+		return -ENODEV;
+
+	if (!master) {
+		dev_err(pdev, "DSA master Ethernet device not found!\n");
+		return -EINVAL;
+	}
+
+	if (ops->port_enable) {
+		struct dsa_port_pdata *port_pdata;
+
+		port_pdata = dev_get_parent_plat(pdev);
+		err = ops->port_enable(dev, port_pdata->index,
+				       port_pdata->phy);
+		if (err)
+			return err;
+
+		err = ops->port_enable(dev, priv->cpu_port,
+				       priv->cpu_port_fixed_phy);
+		if (err)
+			return err;
+	}
+
+	return eth_get_ops(master)->start(master);
+}
+
+/* Stop the desired port, the CPU port and the master Eth interface */
+static void dsa_port_stop(struct udevice *pdev)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+	struct udevice *master = dsa_get_master(dev);
+	struct dsa_ops *ops = dsa_get_ops(dev);
+
+	if (!priv)
+		return;
+
+	if (ops->port_disable) {
+		struct dsa_port_pdata *port_pdata;
+
+		port_pdata = dev_get_parent_plat(pdev);
+		ops->port_disable(dev, port_pdata->index, port_pdata->phy);
+		ops->port_disable(dev, priv->cpu_port, NULL);
+	}
+
+	/*
+	 * stop master only if it's active, don't probe it otherwise.
+	 * Under normal usage it would be active because we're using it, but
+	 * during tear-down it may have been removed ahead of us.
+	 */
+	if (master && device_active(master))
+		eth_get_ops(master)->stop(master);
+}
+
+/*
+ * Insert a DSA tag and call master Ethernet send on the resulting packet
+ * We copy the frame to a stack buffer where we have reserved headroom and
+ * tailroom space.  Headroom and tailroom are set to 0.
+ */
+static int dsa_port_send(struct udevice *pdev, void *packet, int length)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+	int head = priv->headroom, tail = priv->tailroom;
+	struct udevice *master = dsa_get_master(dev);
+	struct dsa_ops *ops = dsa_get_ops(dev);
+	uchar dsa_packet_tmp[PKTSIZE_ALIGN];
+	struct dsa_port_pdata *port_pdata;
+	int err;
+
+	if (!master)
+		return -EINVAL;
+
+	if (length + head + tail > PKTSIZE_ALIGN)
+		return -EINVAL;
+
+	memset(dsa_packet_tmp, 0, head);
+	memset(dsa_packet_tmp + head + length, 0, tail);
+	memcpy(dsa_packet_tmp + head, packet, length);
+	length += head + tail;
+	/* copy back to preserve original buffer alignment */
+	memcpy(packet, dsa_packet_tmp, length);
+
+	port_pdata = dev_get_parent_plat(pdev);
+	err = ops->xmit(dev, port_pdata->index, packet, length);
+	if (err)
+		return err;
+
+	return eth_get_ops(master)->send(master, packet, length);
+}
+
+/* Receive a frame from master Ethernet, process it and pass it on */
+static int dsa_port_recv(struct udevice *pdev, int flags, uchar **packetp)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+	int head = priv->headroom, tail = priv->tailroom;
+	struct udevice *master = dsa_get_master(dev);
+	struct dsa_ops *ops = dsa_get_ops(dev);
+	struct dsa_port_pdata *port_pdata;
+	int length, port_index, err;
+
+	if (!master)
+		return -EINVAL;
+
+	length = eth_get_ops(master)->recv(master, flags, packetp);
+	if (length <= 0)
+		return length;
+
+	/*
+	 * If we receive frames from a different port or frames that DSA driver
+	 * doesn't like we discard them here.
+	 * In case of discard we return with no frame and expect to be called
+	 * again instead of looping here, so upper layer can deal with timeouts.
+	 */
+	port_pdata = dev_get_parent_plat(pdev);
+	err = ops->rcv(dev, &port_index, *packetp, length);
+	if (err || port_index != port_pdata->index || (length <= head + tail)) {
+		if (eth_get_ops(master)->free_pkt)
+			eth_get_ops(master)->free_pkt(master, *packetp, length);
+		return -EAGAIN;
+	}
+
+	/*
+	 * We move the pointer over headroom here to avoid a copy.  If free_pkt
+	 * gets called we move the pointer back before calling master free_pkt.
+	 */
+	*packetp += head;
+
+	return length - head - tail;
+}
+
+static int dsa_port_free_pkt(struct udevice *pdev, uchar *packet, int length)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct udevice *master = dsa_get_master(dev);
+	struct dsa_priv *priv;
+
+	if (!master)
+		return -EINVAL;
+
+	priv = dev_get_uclass_priv(dev);
+	if (eth_get_ops(master)->free_pkt) {
+		/* return the original pointer and length to master Eth */
+		packet -= priv->headroom;
+		length += priv->headroom - priv->tailroom;
+
+		return eth_get_ops(master)->free_pkt(master, packet, length);
+	}
+
+	return 0;
+}
+
+static int dsa_port_of_to_pdata(struct udevice *pdev)
+{
+	struct dsa_port_pdata *port_pdata;
+	struct dsa_pdata *dsa_pdata;
+	struct eth_pdata *eth_pdata;
+	struct udevice *dev;
+	const char *label;
+	u32 index;
+	int err;
+
+	if (!pdev)
+		return -ENODEV;
+
+	err = ofnode_read_u32(dev_ofnode(pdev), "reg", &index);
+	if (err)
+		return err;
+
+	dev = dev_get_parent(pdev);
+	dsa_pdata = dev_get_uclass_plat(dev);
+
+	port_pdata = dev_get_parent_plat(pdev);
+	port_pdata->index = index;
+
+	label = ofnode_read_string(dev_ofnode(pdev), "label");
+	if (label)
+		strncpy(port_pdata->name, label, DSA_PORT_NAME_LENGTH);
+
+	eth_pdata = dev_get_plat(pdev);
+	eth_pdata->priv_pdata = port_pdata;
+
+	dev_dbg(pdev, "port %d node %s\n", port_pdata->index,
+		ofnode_get_name(dev_ofnode(pdev)));
+
+	return 0;
+}
+
+static const struct eth_ops dsa_port_ops = {
+	.start		= dsa_port_start,
+	.send		= dsa_port_send,
+	.recv		= dsa_port_recv,
+	.stop		= dsa_port_stop,
+	.free_pkt	= dsa_port_free_pkt,
+};
+
+static int dsa_port_probe(struct udevice *pdev)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct eth_pdata *eth_pdata, *master_pdata;
+	unsigned char env_enetaddr[ARP_HLEN];
+	struct dsa_port_pdata *port_pdata;
+	struct dsa_priv *dsa_priv;
+	struct udevice *master;
+
+	port_pdata = dev_get_parent_plat(pdev);
+	dsa_priv = dev_get_uclass_priv(dev);
+
+	port_pdata->phy = dm_eth_phy_connect(pdev);
+	if (!port_pdata->phy)
+		return -ENODEV;
+
+	/*
+	 * Inherit port's hwaddr from the DSA master, unless the port already
+	 * has a unique MAC address specified in the environment.
+	 */
+	eth_env_get_enetaddr_by_index("eth", dev_seq(pdev), env_enetaddr);
+	if (!is_zero_ethaddr(env_enetaddr))
+		return 0;
+
+	master = dsa_get_master(dev);
+	if (!master)
+		return 0;
+
+	master_pdata = dev_get_plat(master);
+	eth_pdata = dev_get_plat(pdev);
+	memcpy(eth_pdata->enetaddr, master_pdata->enetaddr, ARP_HLEN);
+	eth_env_set_enetaddr_by_index("eth", dev_seq(pdev),
+				      master_pdata->enetaddr);
+
+	return 0;
+}
+
+static int dsa_port_remove(struct udevice *pdev)
+{
+	struct udevice *dev = dev_get_parent(pdev);
+	struct dsa_port_pdata *port_pdata;
+	struct dsa_priv *dsa_priv;
+
+	port_pdata = dev_get_parent_plat(pdev);
+	dsa_priv = dev_get_uclass_priv(dev);
+
+	port_pdata->phy = NULL;
+
+	return 0;
+}
+
+U_BOOT_DRIVER(dsa_port) = {
+	.name	= DSA_PORT_CHILD_DRV_NAME,
+	.id	= UCLASS_ETH,
+	.ops	= &dsa_port_ops,
+	.probe	= dsa_port_probe,
+	.remove	= dsa_port_remove,
+	.of_to_plat = dsa_port_of_to_pdata,
+	.plat_auto = sizeof(struct eth_pdata),
+};
+
+/*
+ * This function mostly deals with pulling information out of the device tree
+ * into the pdata structure.
+ * It goes through the list of switch ports, registers an eth device for each
+ * front panel port and identifies the cpu port connected to master eth device.
+ * TODO: support cascaded switches
+ */
+static int dsa_post_bind(struct udevice *dev)
+{
+	struct dsa_pdata *pdata = dev_get_uclass_plat(dev);
+	ofnode node = dev_ofnode(dev), pnode;
+	int i, err, first_err = 0;
+
+	if (!pdata || !ofnode_valid(node))
+		return -ENODEV;
+
+	pdata->master_node = ofnode_null();
+
+	node = ofnode_find_subnode(node, "ports");
+	if (!ofnode_valid(node))
+		node = ofnode_find_subnode(node, "ethernet-ports");
+	if (!ofnode_valid(node)) {
+		dev_err(dev, "ports node is missing under DSA device!\n");
+		return -EINVAL;
+	}
+
+	pdata->num_ports = ofnode_get_child_count(node);
+	if (pdata->num_ports <= 0 || pdata->num_ports > DSA_MAX_PORTS) {
+		dev_err(dev, "invalid number of ports (%d)\n",
+			pdata->num_ports);
+		return -EINVAL;
+	}
+
+	/* look for the CPU port */
+	ofnode_for_each_subnode(pnode, node) {
+		u32 ethernet;
+
+		if (ofnode_read_u32(pnode, "ethernet", &ethernet))
+			continue;
+
+		pdata->master_node = ofnode_get_by_phandle(ethernet);
+		pdata->cpu_port_node = pnode;
+		break;
+	}
+
+	if (!ofnode_valid(pdata->master_node)) {
+		dev_err(dev, "master eth node missing!\n");
+		return -EINVAL;
+	}
+
+	if (ofnode_read_u32(pnode, "reg", &pdata->cpu_port)) {
+		dev_err(dev, "CPU port node not valid!\n");
+		return -EINVAL;
+	}
+
+	dev_dbg(dev, "master node %s on port %d\n",
+		ofnode_get_name(pdata->master_node), pdata->cpu_port);
+
+	for (i = 0; i < pdata->num_ports; i++) {
+		char name[DSA_PORT_NAME_LENGTH];
+		struct udevice *pdev;
+
+		/*
+		 * If this is the CPU port don't register it as an ETH device,
+		 * we skip it on purpose since I/O to/from it from the CPU
+		 * isn't useful.
+		 */
+		if (i == pdata->cpu_port)
+			continue;
+
+		/*
+		 * Set up default port names.  If present, DT port labels
+		 * will override the default port names.
+		 */
+		snprintf(name, DSA_PORT_NAME_LENGTH, "%s@%d", dev->name, i);
+
+		ofnode_for_each_subnode(pnode, node) {
+			u32 reg;
+
+			if (ofnode_read_u32(pnode, "reg", &reg))
+				continue;
+
+			if (reg == i)
+				break;
+		}
+
+		/*
+		 * skip registration if port id not found or if the port
+		 * is explicitly disabled in DT
+		 */
+		if (!ofnode_valid(pnode) || !ofnode_is_available(pnode))
+			continue;
+
+		err = device_bind_driver_to_node(dev, DSA_PORT_CHILD_DRV_NAME,
+						 name, pnode, &pdev);
+		if (pdev) {
+			struct dsa_port_pdata *port_pdata;
+
+			port_pdata = dev_get_parent_plat(pdev);
+			strncpy(port_pdata->name, name, DSA_PORT_NAME_LENGTH);
+			pdev->name = port_pdata->name;
+		}
+
+		/* try to bind all ports but keep 1st error */
+		if (err && !first_err)
+			first_err = err;
+	}
+
+	if (first_err)
+		return first_err;
+
+	dev_dbg(dev, "DSA ports successfully bound\n");
+
+	return 0;
+}
+
+/**
+ * Initialize the uclass per device internal state structure (priv).
+ * TODO: pick up references to other switch devices here, if we're cascaded.
+ */
+static int dsa_pre_probe(struct udevice *dev)
+{
+	struct dsa_pdata *pdata = dev_get_uclass_plat(dev);
+	struct dsa_priv *priv = dev_get_uclass_priv(dev);
+
+	if (!pdata || !priv)
+		return -ENODEV;
+
+	priv->num_ports = pdata->num_ports;
+	priv->cpu_port = pdata->cpu_port;
+	priv->cpu_port_fixed_phy = fixed_phy_create(pdata->cpu_port_node);
+	if (!priv->cpu_port_fixed_phy) {
+		dev_err(dev, "Failed to register fixed-link for CPU port\n");
+		return -ENODEV;
+	}
+
+	uclass_find_device_by_ofnode(UCLASS_ETH, pdata->master_node,
+				     &priv->master_dev);
+	return 0;
+}
+
+UCLASS_DRIVER(dsa) = {
+	.id = UCLASS_DSA,
+	.name = "dsa",
+	.post_bind = dsa_post_bind,
+	.pre_probe = dsa_pre_probe,
+	.per_device_auto = sizeof(struct dsa_priv),
+	.per_device_plat_auto = sizeof(struct dsa_pdata),
+	.per_child_plat_auto = sizeof(struct dsa_port_pdata),
+	.flags = DM_UC_FLAG_SEQ_ALIAS,
+};