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, 493 insertions, 0 deletions

diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c
new file mode 100644
index 000000000..7450904e3
--- /dev/null
+++ b/drivers/char/ipmi/bt-bmc.c
@@ -0,0 +1,493 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2015-2016, IBM Corporation.
+ */
+
+#include <linux/atomic.h>
+#include <linux/bt-bmc.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+
+/*
+ * This is a BMC device used to communicate to the host
+ */
+#define DEVICE_NAME	"ipmi-bt-host"
+
+#define BT_IO_BASE	0xe4
+#define BT_IRQ		10
+
+#define BT_CR0		0x0
+#define   BT_CR0_IO_BASE		16
+#define   BT_CR0_IRQ			12
+#define   BT_CR0_EN_CLR_SLV_RDP		0x8
+#define   BT_CR0_EN_CLR_SLV_WRP		0x4
+#define   BT_CR0_ENABLE_IBT		0x1
+#define BT_CR1		0x4
+#define   BT_CR1_IRQ_H2B	0x01
+#define   BT_CR1_IRQ_HBUSY	0x40
+#define BT_CR2		0x8
+#define   BT_CR2_IRQ_H2B	0x01
+#define   BT_CR2_IRQ_HBUSY	0x40
+#define BT_CR3		0xc
+#define BT_CTRL		0x10
+#define   BT_CTRL_B_BUSY		0x80
+#define   BT_CTRL_H_BUSY		0x40
+#define   BT_CTRL_OEM0			0x20
+#define   BT_CTRL_SMS_ATN		0x10
+#define   BT_CTRL_B2H_ATN		0x08
+#define   BT_CTRL_H2B_ATN		0x04
+#define   BT_CTRL_CLR_RD_PTR		0x02
+#define   BT_CTRL_CLR_WR_PTR		0x01
+#define BT_BMC2HOST	0x14
+#define BT_INTMASK	0x18
+#define   BT_INTMASK_B2H_IRQEN		0x01
+#define   BT_INTMASK_B2H_IRQ		0x02
+#define   BT_INTMASK_BMC_HWRST		0x80
+
+#define BT_BMC_BUFFER_SIZE 256
+
+struct bt_bmc {
+	struct device		dev;
+	struct miscdevice	miscdev;
+	void __iomem		*base;
+	int			irq;
+	wait_queue_head_t	queue;
+	struct timer_list	poll_timer;
+	struct mutex		mutex;
+};
+
+static atomic_t open_count = ATOMIC_INIT(0);
+
+static u8 bt_inb(struct bt_bmc *bt_bmc, int reg)
+{
+	return readb(bt_bmc->base + reg);
+}
+
+static void bt_outb(struct bt_bmc *bt_bmc, u8 data, int reg)
+{
+	writeb(data, bt_bmc->base + reg);
+}
+
+static void clr_rd_ptr(struct bt_bmc *bt_bmc)
+{
+	bt_outb(bt_bmc, BT_CTRL_CLR_RD_PTR, BT_CTRL);
+}
+
+static void clr_wr_ptr(struct bt_bmc *bt_bmc)
+{
+	bt_outb(bt_bmc, BT_CTRL_CLR_WR_PTR, BT_CTRL);
+}
+
+static void clr_h2b_atn(struct bt_bmc *bt_bmc)
+{
+	bt_outb(bt_bmc, BT_CTRL_H2B_ATN, BT_CTRL);
+}
+
+static void set_b_busy(struct bt_bmc *bt_bmc)
+{
+	if (!(bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_B_BUSY))
+		bt_outb(bt_bmc, BT_CTRL_B_BUSY, BT_CTRL);
+}
+
+static void clr_b_busy(struct bt_bmc *bt_bmc)
+{
+	if (bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_B_BUSY)
+		bt_outb(bt_bmc, BT_CTRL_B_BUSY, BT_CTRL);
+}
+
+static void set_b2h_atn(struct bt_bmc *bt_bmc)
+{
+	bt_outb(bt_bmc, BT_CTRL_B2H_ATN, BT_CTRL);
+}
+
+static u8 bt_read(struct bt_bmc *bt_bmc)
+{
+	return bt_inb(bt_bmc, BT_BMC2HOST);
+}
+
+static ssize_t bt_readn(struct bt_bmc *bt_bmc, u8 *buf, size_t n)
+{
+	int i;
+
+	for (i = 0; i < n; i++)
+		buf[i] = bt_read(bt_bmc);
+	return n;
+}
+
+static void bt_write(struct bt_bmc *bt_bmc, u8 c)
+{
+	bt_outb(bt_bmc, c, BT_BMC2HOST);
+}
+
+static ssize_t bt_writen(struct bt_bmc *bt_bmc, u8 *buf, size_t n)
+{
+	int i;
+
+	for (i = 0; i < n; i++)
+		bt_write(bt_bmc, buf[i]);
+	return n;
+}
+
+static void set_sms_atn(struct bt_bmc *bt_bmc)
+{
+	bt_outb(bt_bmc, BT_CTRL_SMS_ATN, BT_CTRL);
+}
+
+static struct bt_bmc *file_bt_bmc(struct file *file)
+{
+	return container_of(file->private_data, struct bt_bmc, miscdev);
+}
+
+static int bt_bmc_open(struct inode *inode, struct file *file)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+
+	if (atomic_inc_return(&open_count) == 1) {
+		clr_b_busy(bt_bmc);
+		return 0;
+	}
+
+	atomic_dec(&open_count);
+	return -EBUSY;
+}
+
+/*
+ * The BT (Block Transfer) interface means that entire messages are
+ * buffered by the host before a notification is sent to the BMC that
+ * there is data to be read. The first byte is the length and the
+ * message data follows. The read operation just tries to capture the
+ * whole before returning it to userspace.
+ *
+ * BT Message format :
+ *
+ *    Byte 1  Byte 2     Byte 3  Byte 4  Byte 5:N
+ *    Length  NetFn/LUN  Seq     Cmd     Data
+ *
+ */
+static ssize_t bt_bmc_read(struct file *file, char __user *buf,
+			   size_t count, loff_t *ppos)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+	u8 len;
+	int len_byte = 1;
+	u8 kbuffer[BT_BMC_BUFFER_SIZE];
+	ssize_t ret = 0;
+	ssize_t nread;
+
+	WARN_ON(*ppos);
+
+	if (wait_event_interruptible(bt_bmc->queue,
+				     bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_H2B_ATN))
+		return -ERESTARTSYS;
+
+	mutex_lock(&bt_bmc->mutex);
+
+	if (unlikely(!(bt_inb(bt_bmc, BT_CTRL) & BT_CTRL_H2B_ATN))) {
+		ret = -EIO;
+		goto out_unlock;
+	}
+
+	set_b_busy(bt_bmc);
+	clr_h2b_atn(bt_bmc);
+	clr_rd_ptr(bt_bmc);
+
+	/*
+	 * The BT frames start with the message length, which does not
+	 * include the length byte.
+	 */
+	kbuffer[0] = bt_read(bt_bmc);
+	len = kbuffer[0];
+
+	/* We pass the length back to userspace as well */
+	if (len + 1 > count)
+		len = count - 1;
+
+	while (len) {
+		nread = min_t(ssize_t, len, sizeof(kbuffer) - len_byte);
+
+		bt_readn(bt_bmc, kbuffer + len_byte, nread);
+
+		if (copy_to_user(buf, kbuffer, nread + len_byte)) {
+			ret = -EFAULT;
+			break;
+		}
+		len -= nread;
+		buf += nread + len_byte;
+		ret += nread + len_byte;
+		len_byte = 0;
+	}
+
+	clr_b_busy(bt_bmc);
+
+out_unlock:
+	mutex_unlock(&bt_bmc->mutex);
+	return ret;
+}
+
+/*
+ * BT Message response format :
+ *
+ *    Byte 1  Byte 2     Byte 3  Byte 4  Byte 5  Byte 6:N
+ *    Length  NetFn/LUN  Seq     Cmd     Code    Data
+ */
+static ssize_t bt_bmc_write(struct file *file, const char __user *buf,
+			    size_t count, loff_t *ppos)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+	u8 kbuffer[BT_BMC_BUFFER_SIZE];
+	ssize_t ret = 0;
+	ssize_t nwritten;
+
+	/*
+	 * send a minimum response size
+	 */
+	if (count < 5)
+		return -EINVAL;
+
+	WARN_ON(*ppos);
+
+	/*
+	 * There's no interrupt for clearing bmc busy so we have to
+	 * poll
+	 */
+	if (wait_event_interruptible(bt_bmc->queue,
+				     !(bt_inb(bt_bmc, BT_CTRL) &
+				       (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN))))
+		return -ERESTARTSYS;
+
+	mutex_lock(&bt_bmc->mutex);
+
+	if (unlikely(bt_inb(bt_bmc, BT_CTRL) &
+		     (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN))) {
+		ret = -EIO;
+		goto out_unlock;
+	}
+
+	clr_wr_ptr(bt_bmc);
+
+	while (count) {
+		nwritten = min_t(ssize_t, count, sizeof(kbuffer));
+		if (copy_from_user(&kbuffer, buf, nwritten)) {
+			ret = -EFAULT;
+			break;
+		}
+
+		bt_writen(bt_bmc, kbuffer, nwritten);
+
+		count -= nwritten;
+		buf += nwritten;
+		ret += nwritten;
+	}
+
+	set_b2h_atn(bt_bmc);
+
+out_unlock:
+	mutex_unlock(&bt_bmc->mutex);
+	return ret;
+}
+
+static long bt_bmc_ioctl(struct file *file, unsigned int cmd,
+			 unsigned long param)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+
+	switch (cmd) {
+	case BT_BMC_IOCTL_SMS_ATN:
+		set_sms_atn(bt_bmc);
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static int bt_bmc_release(struct inode *inode, struct file *file)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+
+	atomic_dec(&open_count);
+	set_b_busy(bt_bmc);
+	return 0;
+}
+
+static __poll_t bt_bmc_poll(struct file *file, poll_table *wait)
+{
+	struct bt_bmc *bt_bmc = file_bt_bmc(file);
+	__poll_t mask = 0;
+	u8 ctrl;
+
+	poll_wait(file, &bt_bmc->queue, wait);
+
+	ctrl = bt_inb(bt_bmc, BT_CTRL);
+
+	if (ctrl & BT_CTRL_H2B_ATN)
+		mask |= EPOLLIN;
+
+	if (!(ctrl & (BT_CTRL_H_BUSY | BT_CTRL_B2H_ATN)))
+		mask |= EPOLLOUT;
+
+	return mask;
+}
+
+static const struct file_operations bt_bmc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= bt_bmc_open,
+	.read		= bt_bmc_read,
+	.write		= bt_bmc_write,
+	.release	= bt_bmc_release,
+	.poll		= bt_bmc_poll,
+	.unlocked_ioctl	= bt_bmc_ioctl,
+};
+
+static void poll_timer(struct timer_list *t)
+{
+	struct bt_bmc *bt_bmc = from_timer(bt_bmc, t, poll_timer);
+
+	bt_bmc->poll_timer.expires += msecs_to_jiffies(500);
+	wake_up(&bt_bmc->queue);
+	add_timer(&bt_bmc->poll_timer);
+}
+
+static irqreturn_t bt_bmc_irq(int irq, void *arg)
+{
+	struct bt_bmc *bt_bmc = arg;
+	u32 reg;
+
+	reg = readl(bt_bmc->base + BT_CR2);
+
+	reg &= BT_CR2_IRQ_H2B | BT_CR2_IRQ_HBUSY;
+	if (!reg)
+		return IRQ_NONE;
+
+	/* ack pending IRQs */
+	writel(reg, bt_bmc->base + BT_CR2);
+
+	wake_up(&bt_bmc->queue);
+	return IRQ_HANDLED;
+}
+
+static int bt_bmc_config_irq(struct bt_bmc *bt_bmc,
+			     struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	int rc;
+	u32 reg;
+
+	bt_bmc->irq = platform_get_irq_optional(pdev, 0);
+	if (bt_bmc->irq < 0)
+		return bt_bmc->irq;
+
+	rc = devm_request_irq(dev, bt_bmc->irq, bt_bmc_irq, IRQF_SHARED,
+			      DEVICE_NAME, bt_bmc);
+	if (rc < 0) {
+		dev_warn(dev, "Unable to request IRQ %d\n", bt_bmc->irq);
+		bt_bmc->irq = rc;
+		return rc;
+	}
+
+	/*
+	 * Configure IRQs on the bmc clearing the H2B and HBUSY bits;
+	 * H2B will be asserted when the bmc has data for us; HBUSY
+	 * will be cleared (along with B2H) when we can write the next
+	 * message to the BT buffer
+	 */
+	reg = readl(bt_bmc->base + BT_CR1);
+	reg |= BT_CR1_IRQ_H2B | BT_CR1_IRQ_HBUSY;
+	writel(reg, bt_bmc->base + BT_CR1);
+
+	return 0;
+}
+
+static int bt_bmc_probe(struct platform_device *pdev)
+{
+	struct bt_bmc *bt_bmc;
+	struct device *dev;
+	int rc;
+
+	dev = &pdev->dev;
+	dev_info(dev, "Found bt bmc device\n");
+
+	bt_bmc = devm_kzalloc(dev, sizeof(*bt_bmc), GFP_KERNEL);
+	if (!bt_bmc)
+		return -ENOMEM;
+
+	dev_set_drvdata(&pdev->dev, bt_bmc);
+
+	bt_bmc->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(bt_bmc->base))
+		return PTR_ERR(bt_bmc->base);
+
+	mutex_init(&bt_bmc->mutex);
+	init_waitqueue_head(&bt_bmc->queue);
+
+	bt_bmc->miscdev.minor	= MISC_DYNAMIC_MINOR;
+	bt_bmc->miscdev.name	= DEVICE_NAME;
+	bt_bmc->miscdev.fops	= &bt_bmc_fops;
+	bt_bmc->miscdev.parent = dev;
+	rc = misc_register(&bt_bmc->miscdev);
+	if (rc) {
+		dev_err(dev, "Unable to register misc device\n");
+		return rc;
+	}
+
+	bt_bmc_config_irq(bt_bmc, pdev);
+
+	if (bt_bmc->irq >= 0) {
+		dev_info(dev, "Using IRQ %d\n", bt_bmc->irq);
+	} else {
+		dev_info(dev, "No IRQ; using timer\n");
+		timer_setup(&bt_bmc->poll_timer, poll_timer, 0);
+		bt_bmc->poll_timer.expires = jiffies + msecs_to_jiffies(10);
+		add_timer(&bt_bmc->poll_timer);
+	}
+
+	writel((BT_IO_BASE << BT_CR0_IO_BASE) |
+		     (BT_IRQ << BT_CR0_IRQ) |
+		     BT_CR0_EN_CLR_SLV_RDP |
+		     BT_CR0_EN_CLR_SLV_WRP |
+		     BT_CR0_ENABLE_IBT,
+		bt_bmc->base + BT_CR0);
+
+	clr_b_busy(bt_bmc);
+
+	return 0;
+}
+
+static int bt_bmc_remove(struct platform_device *pdev)
+{
+	struct bt_bmc *bt_bmc = dev_get_drvdata(&pdev->dev);
+
+	misc_deregister(&bt_bmc->miscdev);
+	if (bt_bmc->irq < 0)
+		del_timer_sync(&bt_bmc->poll_timer);
+	return 0;
+}
+
+static const struct of_device_id bt_bmc_match[] = {
+	{ .compatible = "aspeed,ast2400-ibt-bmc" },
+	{ .compatible = "aspeed,ast2500-ibt-bmc" },
+	{ .compatible = "aspeed,ast2600-ibt-bmc" },
+	{ },
+};
+
+static struct platform_driver bt_bmc_driver = {
+	.driver = {
+		.name		= DEVICE_NAME,
+		.of_match_table = bt_bmc_match,
+	},
+	.probe = bt_bmc_probe,
+	.remove = bt_bmc_remove,
+};
+
+module_platform_driver(bt_bmc_driver);
+
+MODULE_DEVICE_TABLE(of, bt_bmc_match);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alistair Popple <alistair@popple.id.au>");
+MODULE_DESCRIPTION("Linux device interface to the IPMI BT interface");