Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 703 insertions, 0 deletions

diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
new file mode 100644
index 000000000..c90d22f56
--- /dev/null
+++ b/drivers/thunderbolt/eeprom.c
@@ -0,0 +1,703 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Thunderbolt driver - eeprom access
+ *
+ * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
+ * Copyright (C) 2018, Intel Corporation
+ */
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include "tb.h"
+
+/*
+ * tb_eeprom_ctl_write() - write control word
+ */
+static int tb_eeprom_ctl_write(struct tb_switch *sw, struct tb_eeprom_ctl *ctl)
+{
+	return tb_sw_write(sw, ctl, TB_CFG_SWITCH, sw->cap_plug_events + ROUTER_CS_4, 1);
+}
+
+/*
+ * tb_eeprom_ctl_write() - read control word
+ */
+static int tb_eeprom_ctl_read(struct tb_switch *sw, struct tb_eeprom_ctl *ctl)
+{
+	return tb_sw_read(sw, ctl, TB_CFG_SWITCH, sw->cap_plug_events + ROUTER_CS_4, 1);
+}
+
+enum tb_eeprom_transfer {
+	TB_EEPROM_IN,
+	TB_EEPROM_OUT,
+};
+
+/*
+ * tb_eeprom_active - enable rom access
+ *
+ * WARNING: Always disable access after usage. Otherwise the controller will
+ * fail to reprobe.
+ */
+static int tb_eeprom_active(struct tb_switch *sw, bool enable)
+{
+	struct tb_eeprom_ctl ctl;
+	int res = tb_eeprom_ctl_read(sw, &ctl);
+	if (res)
+		return res;
+	if (enable) {
+		ctl.bit_banging_enable = 1;
+		res = tb_eeprom_ctl_write(sw, &ctl);
+		if (res)
+			return res;
+		ctl.fl_cs = 0;
+		return tb_eeprom_ctl_write(sw, &ctl);
+	} else {
+		ctl.fl_cs = 1;
+		res = tb_eeprom_ctl_write(sw, &ctl);
+		if (res)
+			return res;
+		ctl.bit_banging_enable = 0;
+		return tb_eeprom_ctl_write(sw, &ctl);
+	}
+}
+
+/*
+ * tb_eeprom_transfer - transfer one bit
+ *
+ * If TB_EEPROM_IN is passed, then the bit can be retrieved from ctl->fl_do.
+ * If TB_EEPROM_OUT is passed, then ctl->fl_di will be written.
+ */
+static int tb_eeprom_transfer(struct tb_switch *sw, struct tb_eeprom_ctl *ctl,
+			      enum tb_eeprom_transfer direction)
+{
+	int res;
+	if (direction == TB_EEPROM_OUT) {
+		res = tb_eeprom_ctl_write(sw, ctl);
+		if (res)
+			return res;
+	}
+	ctl->fl_sk = 1;
+	res = tb_eeprom_ctl_write(sw, ctl);
+	if (res)
+		return res;
+	if (direction == TB_EEPROM_IN) {
+		res = tb_eeprom_ctl_read(sw, ctl);
+		if (res)
+			return res;
+	}
+	ctl->fl_sk = 0;
+	return tb_eeprom_ctl_write(sw, ctl);
+}
+
+/*
+ * tb_eeprom_out - write one byte to the bus
+ */
+static int tb_eeprom_out(struct tb_switch *sw, u8 val)
+{
+	struct tb_eeprom_ctl ctl;
+	int i;
+	int res = tb_eeprom_ctl_read(sw, &ctl);
+	if (res)
+		return res;
+	for (i = 0; i < 8; i++) {
+		ctl.fl_di = val & 0x80;
+		res = tb_eeprom_transfer(sw, &ctl, TB_EEPROM_OUT);
+		if (res)
+			return res;
+		val <<= 1;
+	}
+	return 0;
+}
+
+/*
+ * tb_eeprom_in - read one byte from the bus
+ */
+static int tb_eeprom_in(struct tb_switch *sw, u8 *val)
+{
+	struct tb_eeprom_ctl ctl;
+	int i;
+	int res = tb_eeprom_ctl_read(sw, &ctl);
+	if (res)
+		return res;
+	*val = 0;
+	for (i = 0; i < 8; i++) {
+		*val <<= 1;
+		res = tb_eeprom_transfer(sw, &ctl, TB_EEPROM_IN);
+		if (res)
+			return res;
+		*val |= ctl.fl_do;
+	}
+	return 0;
+}
+
+/*
+ * tb_eeprom_get_drom_offset - get drom offset within eeprom
+ */
+static int tb_eeprom_get_drom_offset(struct tb_switch *sw, u16 *offset)
+{
+	struct tb_cap_plug_events cap;
+	int res;
+
+	if (!sw->cap_plug_events) {
+		tb_sw_warn(sw, "no TB_CAP_PLUG_EVENTS, cannot read eeprom\n");
+		return -ENODEV;
+	}
+	res = tb_sw_read(sw, &cap, TB_CFG_SWITCH, sw->cap_plug_events,
+			     sizeof(cap) / 4);
+	if (res)
+		return res;
+
+	if (!cap.eeprom_ctl.present || cap.eeprom_ctl.not_present) {
+		tb_sw_warn(sw, "no NVM\n");
+		return -ENODEV;
+	}
+
+	if (cap.drom_offset > 0xffff) {
+		tb_sw_warn(sw, "drom offset is larger than 0xffff: %#x\n",
+				cap.drom_offset);
+		return -ENXIO;
+	}
+	*offset = cap.drom_offset;
+	return 0;
+}
+
+/*
+ * tb_eeprom_read_n - read count bytes from offset into val
+ */
+static int tb_eeprom_read_n(struct tb_switch *sw, u16 offset, u8 *val,
+		size_t count)
+{
+	u16 drom_offset;
+	int i, res;
+
+	res = tb_eeprom_get_drom_offset(sw, &drom_offset);
+	if (res)
+		return res;
+
+	offset += drom_offset;
+
+	res = tb_eeprom_active(sw, true);
+	if (res)
+		return res;
+	res = tb_eeprom_out(sw, 3);
+	if (res)
+		return res;
+	res = tb_eeprom_out(sw, offset >> 8);
+	if (res)
+		return res;
+	res = tb_eeprom_out(sw, offset);
+	if (res)
+		return res;
+	for (i = 0; i < count; i++) {
+		res = tb_eeprom_in(sw, val + i);
+		if (res)
+			return res;
+	}
+	return tb_eeprom_active(sw, false);
+}
+
+static u8 tb_crc8(u8 *data, int len)
+{
+	int i, j;
+	u8 val = 0xff;
+	for (i = 0; i < len; i++) {
+		val ^= data[i];
+		for (j = 0; j < 8; j++)
+			val = (val << 1) ^ ((val & 0x80) ? 7 : 0);
+	}
+	return val;
+}
+
+static u32 tb_crc32(void *data, size_t len)
+{
+	return ~__crc32c_le(~0, data, len);
+}
+
+#define TB_DROM_DATA_START		13
+#define TB_DROM_HEADER_SIZE		22
+#define USB4_DROM_HEADER_SIZE		16
+
+struct tb_drom_header {
+	/* BYTE 0 */
+	u8 uid_crc8; /* checksum for uid */
+	/* BYTES 1-8 */
+	u64 uid;
+	/* BYTES 9-12 */
+	u32 data_crc32; /* checksum for data_len bytes starting at byte 13 */
+	/* BYTE 13 */
+	u8 device_rom_revision; /* should be <= 1 */
+	u16 data_len:12;
+	u8 reserved:4;
+	/* BYTES 16-21 - Only for TBT DROM, nonexistent in USB4 DROM */
+	u16 vendor_id;
+	u16 model_id;
+	u8 model_rev;
+	u8 eeprom_rev;
+} __packed;
+
+enum tb_drom_entry_type {
+	/* force unsigned to prevent "one-bit signed bitfield" warning */
+	TB_DROM_ENTRY_GENERIC = 0U,
+	TB_DROM_ENTRY_PORT,
+};
+
+struct tb_drom_entry_header {
+	u8 len;
+	u8 index:6;
+	bool port_disabled:1; /* only valid if type is TB_DROM_ENTRY_PORT */
+	enum tb_drom_entry_type type:1;
+} __packed;
+
+struct tb_drom_entry_generic {
+	struct tb_drom_entry_header header;
+	u8 data[];
+} __packed;
+
+struct tb_drom_entry_port {
+	/* BYTES 0-1 */
+	struct tb_drom_entry_header header;
+	/* BYTE 2 */
+	u8 dual_link_port_rid:4;
+	u8 link_nr:1;
+	u8 unknown1:2;
+	bool has_dual_link_port:1;
+
+	/* BYTE 3 */
+	u8 dual_link_port_nr:6;
+	u8 unknown2:2;
+
+	/* BYTES 4 - 5 TODO decode */
+	u8 micro2:4;
+	u8 micro1:4;
+	u8 micro3;
+
+	/* BYTES 6-7, TODO: verify (find hardware that has these set) */
+	u8 peer_port_rid:4;
+	u8 unknown3:3;
+	bool has_peer_port:1;
+	u8 peer_port_nr:6;
+	u8 unknown4:2;
+} __packed;
+
+/* USB4 product descriptor */
+struct tb_drom_entry_desc {
+	struct tb_drom_entry_header header;
+	u16 bcdUSBSpec;
+	u16 idVendor;
+	u16 idProduct;
+	u16 bcdProductFWRevision;
+	u32 TID;
+	u8 productHWRevision;
+};
+
+/**
+ * tb_drom_read_uid_only() - Read UID directly from DROM
+ * @sw: Router whose UID to read
+ * @uid: UID is placed here
+ *
+ * Does not use the cached copy in sw->drom. Used during resume to check switch
+ * identity.
+ */
+int tb_drom_read_uid_only(struct tb_switch *sw, u64 *uid)
+{
+	u8 data[9];
+	u8 crc;
+	int res;
+
+	/* read uid */
+	res = tb_eeprom_read_n(sw, 0, data, 9);
+	if (res)
+		return res;
+
+	crc = tb_crc8(data + 1, 8);
+	if (crc != data[0]) {
+		tb_sw_warn(sw, "uid crc8 mismatch (expected: %#x, got: %#x)\n",
+				data[0], crc);
+		return -EIO;
+	}
+
+	*uid = *(u64 *)(data+1);
+	return 0;
+}
+
+static int tb_drom_parse_entry_generic(struct tb_switch *sw,
+		struct tb_drom_entry_header *header)
+{
+	const struct tb_drom_entry_generic *entry =
+		(const struct tb_drom_entry_generic *)header;
+
+	switch (header->index) {
+	case 1:
+		/* Length includes 2 bytes header so remove it before copy */
+		sw->vendor_name = kstrndup(entry->data,
+			header->len - sizeof(*header), GFP_KERNEL);
+		if (!sw->vendor_name)
+			return -ENOMEM;
+		break;
+
+	case 2:
+		sw->device_name = kstrndup(entry->data,
+			header->len - sizeof(*header), GFP_KERNEL);
+		if (!sw->device_name)
+			return -ENOMEM;
+		break;
+	case 9: {
+		const struct tb_drom_entry_desc *desc =
+			(const struct tb_drom_entry_desc *)entry;
+
+		if (!sw->vendor && !sw->device) {
+			sw->vendor = desc->idVendor;
+			sw->device = desc->idProduct;
+		}
+		break;
+	}
+	}
+
+	return 0;
+}
+
+static int tb_drom_parse_entry_port(struct tb_switch *sw,
+				    struct tb_drom_entry_header *header)
+{
+	struct tb_port *port;
+	int res;
+	enum tb_port_type type;
+
+	/*
+	 * Some DROMs list more ports than the controller actually has
+	 * so we skip those but allow the parser to continue.
+	 */
+	if (header->index > sw->config.max_port_number) {
+		dev_info_once(&sw->dev, "ignoring unnecessary extra entries in DROM\n");
+		return 0;
+	}
+
+	port = &sw->ports[header->index];
+	port->disabled = header->port_disabled;
+	if (port->disabled)
+		return 0;
+
+	res = tb_port_read(port, &type, TB_CFG_PORT, 2, 1);
+	if (res)
+		return res;
+	type &= 0xffffff;
+
+	if (type == TB_TYPE_PORT) {
+		struct tb_drom_entry_port *entry = (void *) header;
+		if (header->len != sizeof(*entry)) {
+			tb_sw_warn(sw,
+				"port entry has size %#x (expected %#zx)\n",
+				header->len, sizeof(struct tb_drom_entry_port));
+			return -EIO;
+		}
+		port->link_nr = entry->link_nr;
+		if (entry->has_dual_link_port)
+			port->dual_link_port =
+				&port->sw->ports[entry->dual_link_port_nr];
+	}
+	return 0;
+}
+
+/*
+ * tb_drom_parse_entries - parse the linked list of drom entries
+ *
+ * Drom must have been copied to sw->drom.
+ */
+static int tb_drom_parse_entries(struct tb_switch *sw, size_t header_size)
+{
+	struct tb_drom_header *header = (void *) sw->drom;
+	u16 pos = header_size;
+	u16 drom_size = header->data_len + TB_DROM_DATA_START;
+	int res;
+
+	while (pos < drom_size) {
+		struct tb_drom_entry_header *entry = (void *) (sw->drom + pos);
+		if (pos + 1 == drom_size || pos + entry->len > drom_size
+				|| !entry->len) {
+			tb_sw_warn(sw, "DROM buffer overrun\n");
+			return -EILSEQ;
+		}
+
+		switch (entry->type) {
+		case TB_DROM_ENTRY_GENERIC:
+			res = tb_drom_parse_entry_generic(sw, entry);
+			break;
+		case TB_DROM_ENTRY_PORT:
+			res = tb_drom_parse_entry_port(sw, entry);
+			break;
+		}
+		if (res)
+			return res;
+
+		pos += entry->len;
+	}
+	return 0;
+}
+
+/*
+ * tb_drom_copy_efi - copy drom supplied by EFI to sw->drom if present
+ */
+static int tb_drom_copy_efi(struct tb_switch *sw, u16 *size)
+{
+	struct device *dev = &sw->tb->nhi->pdev->dev;
+	int len, res;
+
+	len = device_property_count_u8(dev, "ThunderboltDROM");
+	if (len < 0 || len < sizeof(struct tb_drom_header))
+		return -EINVAL;
+
+	sw->drom = kmalloc(len, GFP_KERNEL);
+	if (!sw->drom)
+		return -ENOMEM;
+
+	res = device_property_read_u8_array(dev, "ThunderboltDROM", sw->drom,
+									len);
+	if (res)
+		goto err;
+
+	*size = ((struct tb_drom_header *)sw->drom)->data_len +
+							  TB_DROM_DATA_START;
+	if (*size > len)
+		goto err;
+
+	return 0;
+
+err:
+	kfree(sw->drom);
+	sw->drom = NULL;
+	return -EINVAL;
+}
+
+static int tb_drom_copy_nvm(struct tb_switch *sw, u16 *size)
+{
+	u32 drom_offset;
+	int ret;
+
+	if (!sw->dma_port)
+		return -ENODEV;
+
+	ret = tb_sw_read(sw, &drom_offset, TB_CFG_SWITCH,
+			 sw->cap_plug_events + 12, 1);
+	if (ret)
+		return ret;
+
+	if (!drom_offset)
+		return -ENODEV;
+
+	ret = dma_port_flash_read(sw->dma_port, drom_offset + 14, size,
+				  sizeof(*size));
+	if (ret)
+		return ret;
+
+	/* Size includes CRC8 + UID + CRC32 */
+	*size += 1 + 8 + 4;
+	sw->drom = kzalloc(*size, GFP_KERNEL);
+	if (!sw->drom)
+		return -ENOMEM;
+
+	ret = dma_port_flash_read(sw->dma_port, drom_offset, sw->drom, *size);
+	if (ret)
+		goto err_free;
+
+	/*
+	 * Read UID from the minimal DROM because the one in NVM is just
+	 * a placeholder.
+	 */
+	tb_drom_read_uid_only(sw, &sw->uid);
+	return 0;
+
+err_free:
+	kfree(sw->drom);
+	sw->drom = NULL;
+	return ret;
+}
+
+static int usb4_copy_host_drom(struct tb_switch *sw, u16 *size)
+{
+	int ret;
+
+	ret = usb4_switch_drom_read(sw, 14, size, sizeof(*size));
+	if (ret)
+		return ret;
+
+	/* Size includes CRC8 + UID + CRC32 */
+	*size += 1 + 8 + 4;
+	sw->drom = kzalloc(*size, GFP_KERNEL);
+	if (!sw->drom)
+		return -ENOMEM;
+
+	ret = usb4_switch_drom_read(sw, 0, sw->drom, *size);
+	if (ret) {
+		kfree(sw->drom);
+		sw->drom = NULL;
+	}
+
+	return ret;
+}
+
+static int tb_drom_read_n(struct tb_switch *sw, u16 offset, u8 *val,
+			  size_t count)
+{
+	if (tb_switch_is_usb4(sw))
+		return usb4_switch_drom_read(sw, offset, val, count);
+	return tb_eeprom_read_n(sw, offset, val, count);
+}
+
+static int tb_drom_parse(struct tb_switch *sw)
+{
+	const struct tb_drom_header *header =
+		(const struct tb_drom_header *)sw->drom;
+	u32 crc;
+
+	crc = tb_crc8((u8 *) &header->uid, 8);
+	if (crc != header->uid_crc8) {
+		tb_sw_warn(sw,
+			"DROM UID CRC8 mismatch (expected: %#x, got: %#x)\n",
+			header->uid_crc8, crc);
+		return -EILSEQ;
+	}
+	if (!sw->uid)
+		sw->uid = header->uid;
+	sw->vendor = header->vendor_id;
+	sw->device = header->model_id;
+
+	crc = tb_crc32(sw->drom + TB_DROM_DATA_START, header->data_len);
+	if (crc != header->data_crc32) {
+		tb_sw_warn(sw,
+			"DROM data CRC32 mismatch (expected: %#x, got: %#x), continuing\n",
+			header->data_crc32, crc);
+	}
+
+	return tb_drom_parse_entries(sw, TB_DROM_HEADER_SIZE);
+}
+
+static int usb4_drom_parse(struct tb_switch *sw)
+{
+	const struct tb_drom_header *header =
+		(const struct tb_drom_header *)sw->drom;
+	u32 crc;
+
+	crc = tb_crc32(sw->drom + TB_DROM_DATA_START, header->data_len);
+	if (crc != header->data_crc32) {
+		tb_sw_warn(sw,
+			   "DROM data CRC32 mismatch (expected: %#x, got: %#x), aborting\n",
+			   header->data_crc32, crc);
+		return -EINVAL;
+	}
+
+	return tb_drom_parse_entries(sw, USB4_DROM_HEADER_SIZE);
+}
+
+/**
+ * tb_drom_read() - Copy DROM to sw->drom and parse it
+ * @sw: Router whose DROM to read and parse
+ *
+ * This function reads router DROM and if successful parses the entries and
+ * populates the fields in @sw accordingly. Can be called for any router
+ * generation.
+ *
+ * Returns %0 in case of success and negative errno otherwise.
+ */
+int tb_drom_read(struct tb_switch *sw)
+{
+	u16 size;
+	struct tb_drom_header *header;
+	int res, retries = 1;
+
+	if (sw->drom)
+		return 0;
+
+	if (tb_route(sw) == 0) {
+		/*
+		 * Apple's NHI EFI driver supplies a DROM for the root switch
+		 * in a device property. Use it if available.
+		 */
+		if (tb_drom_copy_efi(sw, &size) == 0)
+			goto parse;
+
+		/* Non-Apple hardware has the DROM as part of NVM */
+		if (tb_drom_copy_nvm(sw, &size) == 0)
+			goto parse;
+
+		/*
+		 * USB4 hosts may support reading DROM through router
+		 * operations.
+		 */
+		if (tb_switch_is_usb4(sw)) {
+			usb4_switch_read_uid(sw, &sw->uid);
+			if (!usb4_copy_host_drom(sw, &size))
+				goto parse;
+		} else {
+			/*
+			 * The root switch contains only a dummy drom
+			 * (header only, no entries). Hardcode the
+			 * configuration here.
+			 */
+			tb_drom_read_uid_only(sw, &sw->uid);
+		}
+
+		return 0;
+	}
+
+	res = tb_drom_read_n(sw, 14, (u8 *) &size, 2);
+	if (res)
+		return res;
+	size &= 0x3ff;
+	size += TB_DROM_DATA_START;
+	tb_sw_dbg(sw, "reading drom (length: %#x)\n", size);
+	if (size < sizeof(*header)) {
+		tb_sw_warn(sw, "drom too small, aborting\n");
+		return -EIO;
+	}
+
+	sw->drom = kzalloc(size, GFP_KERNEL);
+	if (!sw->drom)
+		return -ENOMEM;
+read:
+	res = tb_drom_read_n(sw, 0, sw->drom, size);
+	if (res)
+		goto err;
+
+parse:
+	header = (void *) sw->drom;
+
+	if (header->data_len + TB_DROM_DATA_START != size) {
+		tb_sw_warn(sw, "drom size mismatch\n");
+		if (retries--) {
+			msleep(100);
+			goto read;
+		}
+		goto err;
+	}
+
+	tb_sw_dbg(sw, "DROM version: %d\n", header->device_rom_revision);
+
+	switch (header->device_rom_revision) {
+	case 3:
+		res = usb4_drom_parse(sw);
+		break;
+	default:
+		tb_sw_warn(sw, "DROM device_rom_revision %#x unknown\n",
+			   header->device_rom_revision);
+		fallthrough;
+	case 1:
+		res = tb_drom_parse(sw);
+		break;
+	}
+
+	/* If the DROM parsing fails, wait a moment and retry once */
+	if (res == -EILSEQ && retries--) {
+		tb_sw_warn(sw, "parsing DROM failed\n");
+		msleep(100);
+		goto read;
+	}
+
+	if (!res)
+		return 0;
+
+err:
+	kfree(sw->drom);
+	sw->drom = NULL;
+	return -EIO;
+}