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, 417 insertions, 0 deletions

diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c
new file mode 100644
index 000000000..f5f24a95e
--- /dev/null
+++ b/drivers/clocksource/dw_apb_timer.c
@@ -0,0 +1,417 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * (C) Copyright 2009 Intel Corporation
+ * Author: Jacob Pan (jacob.jun.pan@intel.com)
+ *
+ * Shared with ARM platforms, Jamie Iles, Picochip 2011
+ *
+ * Support for the Synopsys DesignWare APB Timers.
+ */
+#include <linux/dw_apb_timer.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#define APBT_MIN_PERIOD			4
+#define APBT_MIN_DELTA_USEC		200
+
+#define APBTMR_N_LOAD_COUNT		0x00
+#define APBTMR_N_CURRENT_VALUE		0x04
+#define APBTMR_N_CONTROL		0x08
+#define APBTMR_N_EOI			0x0c
+#define APBTMR_N_INT_STATUS		0x10
+
+#define APBTMRS_INT_STATUS		0xa0
+#define APBTMRS_EOI			0xa4
+#define APBTMRS_RAW_INT_STATUS		0xa8
+#define APBTMRS_COMP_VERSION		0xac
+
+#define APBTMR_CONTROL_ENABLE		(1 << 0)
+/* 1: periodic, 0:free running. */
+#define APBTMR_CONTROL_MODE_PERIODIC	(1 << 1)
+#define APBTMR_CONTROL_INT		(1 << 2)
+
+static inline struct dw_apb_clock_event_device *
+ced_to_dw_apb_ced(struct clock_event_device *evt)
+{
+	return container_of(evt, struct dw_apb_clock_event_device, ced);
+}
+
+static inline struct dw_apb_clocksource *
+clocksource_to_dw_apb_clocksource(struct clocksource *cs)
+{
+	return container_of(cs, struct dw_apb_clocksource, cs);
+}
+
+static inline u32 apbt_readl(struct dw_apb_timer *timer, unsigned long offs)
+{
+	return readl(timer->base + offs);
+}
+
+static inline void apbt_writel(struct dw_apb_timer *timer, u32 val,
+			unsigned long offs)
+{
+	writel(val, timer->base + offs);
+}
+
+static inline u32 apbt_readl_relaxed(struct dw_apb_timer *timer, unsigned long offs)
+{
+	return readl_relaxed(timer->base + offs);
+}
+
+static inline void apbt_writel_relaxed(struct dw_apb_timer *timer, u32 val,
+			unsigned long offs)
+{
+	writel_relaxed(val, timer->base + offs);
+}
+
+static void apbt_disable_int(struct dw_apb_timer *timer)
+{
+	u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL);
+
+	ctrl |= APBTMR_CONTROL_INT;
+	apbt_writel(timer, ctrl, APBTMR_N_CONTROL);
+}
+
+/**
+ * dw_apb_clockevent_pause() - stop the clock_event_device from running
+ *
+ * @dw_ced:	The APB clock to stop generating events.
+ */
+void dw_apb_clockevent_pause(struct dw_apb_clock_event_device *dw_ced)
+{
+	disable_irq(dw_ced->timer.irq);
+	apbt_disable_int(&dw_ced->timer);
+}
+
+static void apbt_eoi(struct dw_apb_timer *timer)
+{
+	apbt_readl_relaxed(timer, APBTMR_N_EOI);
+}
+
+static irqreturn_t dw_apb_clockevent_irq(int irq, void *data)
+{
+	struct clock_event_device *evt = data;
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	if (!evt->event_handler) {
+		pr_info("Spurious APBT timer interrupt %d\n", irq);
+		return IRQ_NONE;
+	}
+
+	if (dw_ced->eoi)
+		dw_ced->eoi(&dw_ced->timer);
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static void apbt_enable_int(struct dw_apb_timer *timer)
+{
+	u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL);
+	/* clear pending intr */
+	apbt_readl(timer, APBTMR_N_EOI);
+	ctrl &= ~APBTMR_CONTROL_INT;
+	apbt_writel(timer, ctrl, APBTMR_N_CONTROL);
+}
+
+static int apbt_shutdown(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=shutdown\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_set_oneshot(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=oneshot\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	/*
+	 * set free running mode, this mode will let timer reload max
+	 * timeout which will give time (3min on 25MHz clock) to rearm
+	 * the next event, therefore emulate the one-shot mode.
+	 */
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
+
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/* write again to set free running mode */
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+
+	/*
+	 * DW APB p. 46, load counter with all 1s before starting free
+	 * running mode.
+	 */
+	apbt_writel(&dw_ced->timer, ~0, APBTMR_N_LOAD_COUNT);
+	ctrl &= ~APBTMR_CONTROL_INT;
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_set_periodic(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	unsigned long period = DIV_ROUND_UP(dw_ced->timer.freq, HZ);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=periodic\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl |= APBTMR_CONTROL_MODE_PERIODIC;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/*
+	 * DW APB p. 46, have to disable timer before load counter,
+	 * may cause sync problem.
+	 */
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	udelay(1);
+	pr_debug("Setting clock period %lu for HZ %d\n", period, HZ);
+	apbt_writel(&dw_ced->timer, period, APBTMR_N_LOAD_COUNT);
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_resume(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	pr_debug("%s CPU %d state=resume\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	apbt_enable_int(&dw_ced->timer);
+	return 0;
+}
+
+static int apbt_next_event(unsigned long delta,
+			   struct clock_event_device *evt)
+{
+	u32 ctrl;
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	/* Disable timer */
+	ctrl = apbt_readl_relaxed(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/* write new count */
+	apbt_writel_relaxed(&dw_ced->timer, delta, APBTMR_N_LOAD_COUNT);
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+
+	return 0;
+}
+
+/**
+ * dw_apb_clockevent_init() - use an APB timer as a clock_event_device
+ *
+ * @cpu:	The CPU the events will be targeted at or -1 if CPU affiliation
+ *		isn't required.
+ * @name:	The name used for the timer and the IRQ for it.
+ * @rating:	The rating to give the timer.
+ * @base:	I/O base for the timer registers.
+ * @irq:	The interrupt number to use for the timer.
+ * @freq:	The frequency that the timer counts at.
+ *
+ * This creates a clock_event_device for using with the generic clock layer
+ * but does not start and register it.  This should be done with
+ * dw_apb_clockevent_register() as the next step.  If this is the first time
+ * it has been called for a timer then the IRQ will be requested, if not it
+ * just be enabled to allow CPU hotplug to avoid repeatedly requesting and
+ * releasing the IRQ.
+ */
+struct dw_apb_clock_event_device *
+dw_apb_clockevent_init(int cpu, const char *name, unsigned rating,
+		       void __iomem *base, int irq, unsigned long freq)
+{
+	struct dw_apb_clock_event_device *dw_ced =
+		kzalloc(sizeof(*dw_ced), GFP_KERNEL);
+	int err;
+
+	if (!dw_ced)
+		return NULL;
+
+	dw_ced->timer.base = base;
+	dw_ced->timer.irq = irq;
+	dw_ced->timer.freq = freq;
+
+	clockevents_calc_mult_shift(&dw_ced->ced, freq, APBT_MIN_PERIOD);
+	dw_ced->ced.max_delta_ns = clockevent_delta2ns(0x7fffffff,
+						       &dw_ced->ced);
+	dw_ced->ced.max_delta_ticks = 0x7fffffff;
+	dw_ced->ced.min_delta_ns = clockevent_delta2ns(5000, &dw_ced->ced);
+	dw_ced->ced.min_delta_ticks = 5000;
+	dw_ced->ced.cpumask = cpu < 0 ? cpu_possible_mask : cpumask_of(cpu);
+	dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC |
+				CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
+	dw_ced->ced.set_state_shutdown = apbt_shutdown;
+	dw_ced->ced.set_state_periodic = apbt_set_periodic;
+	dw_ced->ced.set_state_oneshot = apbt_set_oneshot;
+	dw_ced->ced.set_state_oneshot_stopped = apbt_shutdown;
+	dw_ced->ced.tick_resume = apbt_resume;
+	dw_ced->ced.set_next_event = apbt_next_event;
+	dw_ced->ced.irq = dw_ced->timer.irq;
+	dw_ced->ced.rating = rating;
+	dw_ced->ced.name = name;
+
+	dw_ced->eoi = apbt_eoi;
+	err = request_irq(irq, dw_apb_clockevent_irq,
+			  IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
+			  dw_ced->ced.name, &dw_ced->ced);
+	if (err) {
+		pr_err("failed to request timer irq\n");
+		kfree(dw_ced);
+		dw_ced = NULL;
+	}
+
+	return dw_ced;
+}
+
+/**
+ * dw_apb_clockevent_resume() - resume a clock that has been paused.
+ *
+ * @dw_ced:	The APB clock to resume.
+ */
+void dw_apb_clockevent_resume(struct dw_apb_clock_event_device *dw_ced)
+{
+	enable_irq(dw_ced->timer.irq);
+}
+
+/**
+ * dw_apb_clockevent_stop() - stop the clock_event_device and release the IRQ.
+ *
+ * @dw_ced:	The APB clock to stop generating the events.
+ */
+void dw_apb_clockevent_stop(struct dw_apb_clock_event_device *dw_ced)
+{
+	free_irq(dw_ced->timer.irq, &dw_ced->ced);
+}
+
+/**
+ * dw_apb_clockevent_register() - register the clock with the generic layer
+ *
+ * @dw_ced:	The APB clock to register as a clock_event_device.
+ */
+void dw_apb_clockevent_register(struct dw_apb_clock_event_device *dw_ced)
+{
+	apbt_writel(&dw_ced->timer, 0, APBTMR_N_CONTROL);
+	clockevents_register_device(&dw_ced->ced);
+	apbt_enable_int(&dw_ced->timer);
+}
+
+/**
+ * dw_apb_clocksource_start() - start the clocksource counting.
+ *
+ * @dw_cs:	The clocksource to start.
+ *
+ * This is used to start the clocksource before registration and can be used
+ * to enable calibration of timers.
+ */
+void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs)
+{
+	/*
+	 * start count down from 0xffff_ffff. this is done by toggling the
+	 * enable bit then load initial load count to ~0.
+	 */
+	u32 ctrl = apbt_readl(&dw_cs->timer, APBTMR_N_CONTROL);
+
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_cs->timer, ctrl, APBTMR_N_CONTROL);
+	apbt_writel(&dw_cs->timer, ~0, APBTMR_N_LOAD_COUNT);
+	/* enable, mask interrupt */
+	ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
+	ctrl |= (APBTMR_CONTROL_ENABLE | APBTMR_CONTROL_INT);
+	apbt_writel(&dw_cs->timer, ctrl, APBTMR_N_CONTROL);
+	/* read it once to get cached counter value initialized */
+	dw_apb_clocksource_read(dw_cs);
+}
+
+static u64 __apbt_read_clocksource(struct clocksource *cs)
+{
+	u32 current_count;
+	struct dw_apb_clocksource *dw_cs =
+		clocksource_to_dw_apb_clocksource(cs);
+
+	current_count = apbt_readl_relaxed(&dw_cs->timer,
+					APBTMR_N_CURRENT_VALUE);
+
+	return (u64)~current_count;
+}
+
+static void apbt_restart_clocksource(struct clocksource *cs)
+{
+	struct dw_apb_clocksource *dw_cs =
+		clocksource_to_dw_apb_clocksource(cs);
+
+	dw_apb_clocksource_start(dw_cs);
+}
+
+/**
+ * dw_apb_clocksource_init() - use an APB timer as a clocksource.
+ *
+ * @rating:	The rating to give the clocksource.
+ * @name:	The name for the clocksource.
+ * @base:	The I/O base for the timer registers.
+ * @freq:	The frequency that the timer counts at.
+ *
+ * This creates a clocksource using an APB timer but does not yet register it
+ * with the clocksource system.  This should be done with
+ * dw_apb_clocksource_register() as the next step.
+ */
+struct dw_apb_clocksource *
+dw_apb_clocksource_init(unsigned rating, const char *name, void __iomem *base,
+			unsigned long freq)
+{
+	struct dw_apb_clocksource *dw_cs = kzalloc(sizeof(*dw_cs), GFP_KERNEL);
+
+	if (!dw_cs)
+		return NULL;
+
+	dw_cs->timer.base = base;
+	dw_cs->timer.freq = freq;
+	dw_cs->cs.name = name;
+	dw_cs->cs.rating = rating;
+	dw_cs->cs.read = __apbt_read_clocksource;
+	dw_cs->cs.mask = CLOCKSOURCE_MASK(32);
+	dw_cs->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+	dw_cs->cs.resume = apbt_restart_clocksource;
+
+	return dw_cs;
+}
+
+/**
+ * dw_apb_clocksource_register() - register the APB clocksource.
+ *
+ * @dw_cs:	The clocksource to register.
+ */
+void dw_apb_clocksource_register(struct dw_apb_clocksource *dw_cs)
+{
+	clocksource_register_hz(&dw_cs->cs, dw_cs->timer.freq);
+}
+
+/**
+ * dw_apb_clocksource_read() - read the current value of a clocksource.
+ *
+ * @dw_cs:	The clocksource to read.
+ */
+u64 dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs)
+{
+	return (u64)~apbt_readl(&dw_cs->timer, APBTMR_N_CURRENT_VALUE);
+}