diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 971a572248..0e84c22b50 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -37,6 +37,21 @@ config DM_MDIO_MUX This is currently implemented in net/mdio-mux-uclass.c Look in include/miiphy.h for details. +config DM_DSA + bool "Enable Driver Model for DSA switches" + depends on DM_ETH && DM_MDIO + depends on PHY_FIXED + help + Enable driver model for DSA switches + + Adds UCLASS_DSA class supporting switches that follow the Distributed + Switch Architecture (DSA). These switches rely on the presence of a + management switch port connected to an Ethernet controller capable of + receiving frames from the switch. This host Ethernet controller is + called the "master" Ethernet interface in DSA terminology. + This is currently implemented in net/dsa-uclass.c, refer to + include/net/dsa.h for API details. + config MDIO_SANDBOX depends on DM_MDIO && SANDBOX default y diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index ae4425d7a5..d75de368c5 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -46,6 +46,7 @@ enum uclass_id { UCLASS_DISPLAY, /* Display (e.g. DisplayPort, HDMI) */ UCLASS_DSI_HOST, /* Display Serial Interface host */ UCLASS_DMA, /* Direct Memory Access */ + UCLASS_DSA, /* Distributed (Ethernet) Switch Architecture */ UCLASS_EFI, /* EFI managed devices */ UCLASS_ETH, /* Ethernet device */ UCLASS_ETH_PHY, /* Ethernet PHY device */ diff --git a/include/net.h b/include/net.h index 13da69b7c1..b95d6a6f60 100644 --- a/include/net.h +++ b/include/net.h @@ -499,7 +499,13 @@ struct icmp_hdr { * maximum packet size and multiple of 32 bytes = 1536 */ #define PKTSIZE 1522 +#ifndef CONFIG_DM_DSA #define PKTSIZE_ALIGN 1536 +#else +/* Maximum DSA tagging overhead (headroom and/or tailroom) */ +#define DSA_MAX_OVR 256 +#define PKTSIZE_ALIGN (1536 + DSA_MAX_OVR) +#endif /* * Maximum receive ring size; that is, the number of packets diff --git a/include/net/dsa.h b/include/net/dsa.h new file mode 100644 index 0000000000..0f31a908c9 --- /dev/null +++ b/include/net/dsa.h @@ -0,0 +1,165 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright 2019-2021 NXP Semiconductors + */ + +#ifndef __DSA_H__ +#define __DSA_H__ + +#include +#include + +/** + * DSA stands for Distributed Switch Architecture and it is infrastructure + * intended to support drivers for Switches that rely on an intermediary + * Ethernet device for I/O. These switches may support cascading allowing + * them to be arranged as a tree. + * DSA is documented in detail in the Linux kernel documentation under + * Documentation/networking/dsa/dsa.txt + * The network layout of such a switch is shown below: + * + * |------| + * | eth0 | <--- master eth device (regular eth driver) + * |------| + * ^ | + * tag added by switch -->| | + * | | + * | |<-- tag added by DSA driver + * | v + * |--------------------------------------| + * | | CPU port | | <-- DSA (switch) device + * | ------------ | (DSA driver) + * | _________ _________ _________ | + * | | port0 | | port1 | ... | portn | | <-- ports as eth devices + * |-+-------+--+-------+-------+-------+-| ('dsa-port' eth driver) + * + * In U-Boot the intent is to allow access to front panel ports (shown at the + * bottom of the picture) through the master Ethernet dev (eth0 in the picture). + * Front panel ports are presented as regular Ethernet devices in U-Boot and + * they are expected to support the typical networking commands. + * In general DSA switches require the use of tags, extra headers added both by + * software on Tx and by the switch on Rx. These tags carry at a minimum port + * information and switch information for cascaded set-ups. + * In U-Boot these tags are inserted and parsed by the DSA switch driver, the + * class code helps with headroom/tailroom for the extra headers. + * + * TODO: + * - handle switch cascading, for now U-Boot only supports stand-alone switches. + * - Add support to probe DSA switches connected to a MDIO bus, this is needed + * to convert switch drivers that are now under drivers/net/phy. + */ + +#define DSA_PORT_NAME_LENGTH 16 + +/* Maximum number of ports each DSA device can have */ +#define DSA_MAX_PORTS 12 + +/** + * struct dsa_ops - DSA operations + * + * @port_enable: Initialize a switch port for I/O. + * @port_disable: Disable I/O for a port. + * @xmit: Insert the DSA tag for transmission. + * DSA drivers receive a copy of the packet with headroom and + * tailroom reserved and set to 0. 'packet' points to headroom + * and 'length' is updated to include both head and tailroom. + * @rcv: Process the DSA tag on reception and return the port index + * from the h/w provided tag. Return the index via 'portp'. + * 'packet' and 'length' describe the frame as received from + * master including any additional headers. + */ +struct dsa_ops { + int (*port_enable)(struct udevice *dev, int port, + struct phy_device *phy); + void (*port_disable)(struct udevice *dev, int port, + struct phy_device *phy); + int (*xmit)(struct udevice *dev, int port, void *packet, int length); + int (*rcv)(struct udevice *dev, int *portp, void *packet, int length); +}; + +#define dsa_get_ops(dev) ((struct dsa_ops *)(dev)->driver->ops) + +/** + * struct dsa_port_pdata - DSA port platform data + * + * @phy: PHY device associated with this port. + * The uclass code attempts to set this field for all ports except CPU + * port, based on DT information. It may be NULL. + * @index: Port index in the DSA switch, set by the uclass code. + * @name: Name of the port Eth device. If a label property is present in the + * port DT node, it is used as name. + */ +struct dsa_port_pdata { + struct phy_device *phy; + u32 index; + char name[DSA_PORT_NAME_LENGTH]; +}; + +/** + * struct dsa_pdata - Per-device platform data for DSA DM + * + * @num_ports: Number of ports the device has, must be <= DSA_MAX_PORTS. + * This number is extracted from the DT 'ports' node of this + * DSA device, and it counts the CPU port and all the other + * port subnodes including the disabled ones. + * @cpu_port: Index of the switch port linked to the master Ethernet. + * The uclass code sets this based on DT information. + * @master_node: OF node of the host Ethernet controller. + * @cpu_port_node: DT node of the switch's CPU port. + */ +struct dsa_pdata { + int num_ports; + u32 cpu_port; + ofnode master_node; + ofnode cpu_port_node; +}; + +/** + * dsa_set_tagging() - Configure the headroom and/or tailroom sizes + * + * The DSA class code allocates headroom and tailroom on Tx before + * calling the DSA driver's xmit function. + * All drivers must call this at probe time. + * + * @dev: DSA device pointer + * @headroom: Size, in bytes, of headroom needed for the DSA tag. + * @tailroom: Size, in bytes, of tailroom needed for the DSA tag. + * Total headroom and tailroom size should not exceed + * DSA_MAX_OVR. + * @return 0 if OK, -ve on error + */ +int dsa_set_tagging(struct udevice *dev, ushort headroom, ushort tailroom); + +/* DSA helpers */ + +/** + * dsa_get_master() - Return a reference to the master Ethernet device + * + * Can be called at driver probe time or later. + * + * @dev: DSA device pointer + * @return Master Eth 'udevice' pointer if OK, NULL on error + */ +struct udevice *dsa_get_master(struct udevice *dev); + +/** + * dsa_port_get_pdata() - Helper that returns the platdata of an active + * (non-CPU) DSA port device. + * + * Can be called at driver probe time or later. + * + * @pdev: DSA port device pointer + * @return 'dsa_port_pdata' pointer if OK, NULL on error + */ +static inline struct dsa_port_pdata * + dsa_port_get_pdata(struct udevice *pdev) +{ + struct eth_pdata *eth = dev_get_plat(pdev); + + if (!eth) + return NULL; + + return eth->priv_pdata; +} + +#endif /* __DSA_H__ */ diff --git a/net/Makefile b/net/Makefile index 76527f704c..fb3eba840f 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 0000000000..2ce9ddb90d --- /dev/null +++ b/net/dsa-uclass.c @@ -0,0 +1,478 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2019-2021 NXP + */ + +#include +#include +#include +#include +#include +#include +#include + +#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", ðernet)) + 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", ®)) + 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, +};