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().
  ...

5 files changed, 790 insertions, 0 deletions

diff --git a/drivers/dma/hsu/Kconfig b/drivers/dma/hsu/Kconfig
new file mode 100644
index 000000000..af102baec
--- /dev/null
+++ b/drivers/dma/hsu/Kconfig
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# DMA engine configuration for hsu
+config HSU_DMA
+	tristate
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+
+config HSU_DMA_PCI
+	tristate
+	depends on HSU_DMA && PCI
diff --git a/drivers/dma/hsu/Makefile b/drivers/dma/hsu/Makefile
new file mode 100644
index 000000000..61829b1de
--- /dev/null
+++ b/drivers/dma/hsu/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_HSU_DMA)		+= hsu_dma.o
+hsu_dma-objs		:= hsu.o
+
+obj-$(CONFIG_HSU_DMA_PCI)	+= hsu_dma_pci.o
+hsu_dma_pci-objs	:= pci.o
diff --git a/drivers/dma/hsu/hsu.c b/drivers/dma/hsu/hsu.c
new file mode 100644
index 000000000..af5a2e252
--- /dev/null
+++ b/drivers/dma/hsu/hsu.c
@@ -0,0 +1,512 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Core driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ */
+
+/*
+ * DMA channel allocation:
+ * 1. Even number chans are used for DMA Read (UART TX), odd chans for DMA
+ *    Write (UART RX).
+ * 2. 0/1 channel are assigned to port 0, 2/3 chan to port 1, 4/5 chan to
+ *    port 3, and so on.
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/percpu-defs.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+
+#include "hsu.h"
+
+#define HSU_DMA_BUSWIDTHS				\
+	BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED)	|	\
+	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_3_BYTES)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)		|	\
+	BIT(DMA_SLAVE_BUSWIDTH_16_BYTES)
+
+static inline void hsu_chan_disable(struct hsu_dma_chan *hsuc)
+{
+	hsu_chan_writel(hsuc, HSU_CH_CR, 0);
+}
+
+static inline void hsu_chan_enable(struct hsu_dma_chan *hsuc)
+{
+	u32 cr = HSU_CH_CR_CHA;
+
+	if (hsuc->direction == DMA_MEM_TO_DEV)
+		cr &= ~HSU_CH_CR_CHD;
+	else if (hsuc->direction == DMA_DEV_TO_MEM)
+		cr |= HSU_CH_CR_CHD;
+
+	hsu_chan_writel(hsuc, HSU_CH_CR, cr);
+}
+
+static void hsu_dma_chan_start(struct hsu_dma_chan *hsuc)
+{
+	struct dma_slave_config *config = &hsuc->config;
+	struct hsu_dma_desc *desc = hsuc->desc;
+	u32 bsr = 0, mtsr = 0;	/* to shut the compiler up */
+	u32 dcr = HSU_CH_DCR_CHSOE | HSU_CH_DCR_CHEI;
+	unsigned int i, count;
+
+	if (hsuc->direction == DMA_MEM_TO_DEV) {
+		bsr = config->dst_maxburst;
+		mtsr = config->dst_addr_width;
+	} else if (hsuc->direction == DMA_DEV_TO_MEM) {
+		bsr = config->src_maxburst;
+		mtsr = config->src_addr_width;
+	}
+
+	hsu_chan_disable(hsuc);
+
+	hsu_chan_writel(hsuc, HSU_CH_DCR, 0);
+	hsu_chan_writel(hsuc, HSU_CH_BSR, bsr);
+	hsu_chan_writel(hsuc, HSU_CH_MTSR, mtsr);
+
+	/* Set descriptors */
+	count = desc->nents - desc->active;
+	for (i = 0; i < count && i < HSU_DMA_CHAN_NR_DESC; i++) {
+		hsu_chan_writel(hsuc, HSU_CH_DxSAR(i), desc->sg[i].addr);
+		hsu_chan_writel(hsuc, HSU_CH_DxTSR(i), desc->sg[i].len);
+
+		/* Prepare value for DCR */
+		dcr |= HSU_CH_DCR_DESCA(i);
+		dcr |= HSU_CH_DCR_CHTOI(i);	/* timeout bit, see HSU Errata 1 */
+
+		desc->active++;
+	}
+	/* Only for the last descriptor in the chain */
+	dcr |= HSU_CH_DCR_CHSOD(count - 1);
+	dcr |= HSU_CH_DCR_CHDI(count - 1);
+
+	hsu_chan_writel(hsuc, HSU_CH_DCR, dcr);
+
+	hsu_chan_enable(hsuc);
+}
+
+static void hsu_dma_stop_channel(struct hsu_dma_chan *hsuc)
+{
+	hsu_chan_disable(hsuc);
+	hsu_chan_writel(hsuc, HSU_CH_DCR, 0);
+}
+
+static void hsu_dma_start_channel(struct hsu_dma_chan *hsuc)
+{
+	hsu_dma_chan_start(hsuc);
+}
+
+static void hsu_dma_start_transfer(struct hsu_dma_chan *hsuc)
+{
+	struct virt_dma_desc *vdesc;
+
+	/* Get the next descriptor */
+	vdesc = vchan_next_desc(&hsuc->vchan);
+	if (!vdesc) {
+		hsuc->desc = NULL;
+		return;
+	}
+
+	list_del(&vdesc->node);
+	hsuc->desc = to_hsu_dma_desc(vdesc);
+
+	/* Start the channel with a new descriptor */
+	hsu_dma_start_channel(hsuc);
+}
+
+/*
+ *      hsu_dma_get_status() - get DMA channel status
+ *      @chip: HSUART DMA chip
+ *      @nr: DMA channel number
+ *      @status: pointer for DMA Channel Status Register value
+ *
+ *      Description:
+ *      The function reads and clears the DMA Channel Status Register, checks
+ *      if it was a timeout interrupt and returns a corresponding value.
+ *
+ *      Caller should provide a valid pointer for the DMA Channel Status
+ *      Register value that will be returned in @status.
+ *
+ *      Return:
+ *      1 for DMA timeout status, 0 for other DMA status, or error code for
+ *      invalid parameters or no interrupt pending.
+ */
+int hsu_dma_get_status(struct hsu_dma_chip *chip, unsigned short nr,
+		       u32 *status)
+{
+	struct hsu_dma_chan *hsuc;
+	unsigned long flags;
+	u32 sr;
+
+	/* Sanity check */
+	if (nr >= chip->hsu->nr_channels)
+		return -EINVAL;
+
+	hsuc = &chip->hsu->chan[nr];
+
+	/*
+	 * No matter what situation, need read clear the IRQ status
+	 * There is a bug, see Errata 5, HSD 2900918
+	 */
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	sr = hsu_chan_readl(hsuc, HSU_CH_SR);
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+	/* Check if any interrupt is pending */
+	sr &= ~(HSU_CH_SR_DESCE_ANY | HSU_CH_SR_CDESC_ANY);
+	if (!sr)
+		return -EIO;
+
+	/* Timeout IRQ, need wait some time, see Errata 2 */
+	if (sr & HSU_CH_SR_DESCTO_ANY)
+		udelay(2);
+
+	/*
+	 * At this point, at least one of Descriptor Time Out, Channel Error
+	 * or Descriptor Done bits must be set. Clear the Descriptor Time Out
+	 * bits and if sr is still non-zero, it must be channel error or
+	 * descriptor done which are higher priority than timeout and handled
+	 * in hsu_dma_do_irq(). Else, it must be a timeout.
+	 */
+	sr &= ~HSU_CH_SR_DESCTO_ANY;
+
+	*status = sr;
+
+	return sr ? 0 : 1;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_get_status);
+
+/*
+ *      hsu_dma_do_irq() - DMA interrupt handler
+ *      @chip: HSUART DMA chip
+ *      @nr: DMA channel number
+ *      @status: Channel Status Register value
+ *
+ *      Description:
+ *      This function handles Channel Error and Descriptor Done interrupts.
+ *      This function should be called after determining that the DMA interrupt
+ *      is not a normal timeout interrupt, ie. hsu_dma_get_status() returned 0.
+ *
+ *      Return:
+ *      0 for invalid channel number, 1 otherwise.
+ */
+int hsu_dma_do_irq(struct hsu_dma_chip *chip, unsigned short nr, u32 status)
+{
+	struct dma_chan_percpu *stat;
+	struct hsu_dma_chan *hsuc;
+	struct hsu_dma_desc *desc;
+	unsigned long flags;
+
+	/* Sanity check */
+	if (nr >= chip->hsu->nr_channels)
+		return 0;
+
+	hsuc = &chip->hsu->chan[nr];
+	stat = this_cpu_ptr(hsuc->vchan.chan.local);
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	desc = hsuc->desc;
+	if (desc) {
+		if (status & HSU_CH_SR_CHE) {
+			desc->status = DMA_ERROR;
+		} else if (desc->active < desc->nents) {
+			hsu_dma_start_channel(hsuc);
+		} else {
+			vchan_cookie_complete(&desc->vdesc);
+			desc->status = DMA_COMPLETE;
+			stat->bytes_transferred += desc->length;
+			hsu_dma_start_transfer(hsuc);
+		}
+	}
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+	return 1;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_do_irq);
+
+static struct hsu_dma_desc *hsu_dma_alloc_desc(unsigned int nents)
+{
+	struct hsu_dma_desc *desc;
+
+	desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	desc->sg = kcalloc(nents, sizeof(*desc->sg), GFP_NOWAIT);
+	if (!desc->sg) {
+		kfree(desc);
+		return NULL;
+	}
+
+	return desc;
+}
+
+static void hsu_dma_desc_free(struct virt_dma_desc *vdesc)
+{
+	struct hsu_dma_desc *desc = to_hsu_dma_desc(vdesc);
+
+	kfree(desc->sg);
+	kfree(desc);
+}
+
+static struct dma_async_tx_descriptor *hsu_dma_prep_slave_sg(
+		struct dma_chan *chan, struct scatterlist *sgl,
+		unsigned int sg_len, enum dma_transfer_direction direction,
+		unsigned long flags, void *context)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	struct hsu_dma_desc *desc;
+	struct scatterlist *sg;
+	unsigned int i;
+
+	desc = hsu_dma_alloc_desc(sg_len);
+	if (!desc)
+		return NULL;
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		desc->sg[i].addr = sg_dma_address(sg);
+		desc->sg[i].len = sg_dma_len(sg);
+
+		desc->length += sg_dma_len(sg);
+	}
+
+	desc->nents = sg_len;
+	desc->direction = direction;
+	/* desc->active = 0 by kzalloc */
+	desc->status = DMA_IN_PROGRESS;
+
+	return vchan_tx_prep(&hsuc->vchan, &desc->vdesc, flags);
+}
+
+static void hsu_dma_issue_pending(struct dma_chan *chan)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	if (vchan_issue_pending(&hsuc->vchan) && !hsuc->desc)
+		hsu_dma_start_transfer(hsuc);
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+}
+
+static size_t hsu_dma_active_desc_size(struct hsu_dma_chan *hsuc)
+{
+	struct hsu_dma_desc *desc = hsuc->desc;
+	size_t bytes = 0;
+	int i;
+
+	for (i = desc->active; i < desc->nents; i++)
+		bytes += desc->sg[i].len;
+
+	i = HSU_DMA_CHAN_NR_DESC - 1;
+	do {
+		bytes += hsu_chan_readl(hsuc, HSU_CH_DxTSR(i));
+	} while (--i >= 0);
+
+	return bytes;
+}
+
+static enum dma_status hsu_dma_tx_status(struct dma_chan *chan,
+	dma_cookie_t cookie, struct dma_tx_state *state)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	struct virt_dma_desc *vdesc;
+	enum dma_status status;
+	size_t bytes;
+	unsigned long flags;
+
+	status = dma_cookie_status(chan, cookie, state);
+	if (status == DMA_COMPLETE)
+		return status;
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	vdesc = vchan_find_desc(&hsuc->vchan, cookie);
+	if (hsuc->desc && cookie == hsuc->desc->vdesc.tx.cookie) {
+		bytes = hsu_dma_active_desc_size(hsuc);
+		dma_set_residue(state, bytes);
+		status = hsuc->desc->status;
+	} else if (vdesc) {
+		bytes = to_hsu_dma_desc(vdesc)->length;
+		dma_set_residue(state, bytes);
+	}
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+	return status;
+}
+
+static int hsu_dma_slave_config(struct dma_chan *chan,
+				struct dma_slave_config *config)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+
+	memcpy(&hsuc->config, config, sizeof(hsuc->config));
+
+	return 0;
+}
+
+static int hsu_dma_pause(struct dma_chan *chan)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	if (hsuc->desc && hsuc->desc->status == DMA_IN_PROGRESS) {
+		hsu_chan_disable(hsuc);
+		hsuc->desc->status = DMA_PAUSED;
+	}
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+	return 0;
+}
+
+static int hsu_dma_resume(struct dma_chan *chan)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	unsigned long flags;
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+	if (hsuc->desc && hsuc->desc->status == DMA_PAUSED) {
+		hsuc->desc->status = DMA_IN_PROGRESS;
+		hsu_chan_enable(hsuc);
+	}
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+	return 0;
+}
+
+static int hsu_dma_terminate_all(struct dma_chan *chan)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+	unsigned long flags;
+	LIST_HEAD(head);
+
+	spin_lock_irqsave(&hsuc->vchan.lock, flags);
+
+	hsu_dma_stop_channel(hsuc);
+	if (hsuc->desc) {
+		hsu_dma_desc_free(&hsuc->desc->vdesc);
+		hsuc->desc = NULL;
+	}
+
+	vchan_get_all_descriptors(&hsuc->vchan, &head);
+	spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+	vchan_dma_desc_free_list(&hsuc->vchan, &head);
+
+	return 0;
+}
+
+static void hsu_dma_free_chan_resources(struct dma_chan *chan)
+{
+	vchan_free_chan_resources(to_virt_chan(chan));
+}
+
+static void hsu_dma_synchronize(struct dma_chan *chan)
+{
+	struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+
+	vchan_synchronize(&hsuc->vchan);
+}
+
+int hsu_dma_probe(struct hsu_dma_chip *chip)
+{
+	struct hsu_dma *hsu;
+	void __iomem *addr = chip->regs + chip->offset;
+	unsigned short i;
+	int ret;
+
+	hsu = devm_kzalloc(chip->dev, sizeof(*hsu), GFP_KERNEL);
+	if (!hsu)
+		return -ENOMEM;
+
+	chip->hsu = hsu;
+
+	/* Calculate nr_channels from the IO space length */
+	hsu->nr_channels = (chip->length - chip->offset) / HSU_DMA_CHAN_LENGTH;
+
+	hsu->chan = devm_kcalloc(chip->dev, hsu->nr_channels,
+				 sizeof(*hsu->chan), GFP_KERNEL);
+	if (!hsu->chan)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&hsu->dma.channels);
+	for (i = 0; i < hsu->nr_channels; i++) {
+		struct hsu_dma_chan *hsuc = &hsu->chan[i];
+
+		hsuc->vchan.desc_free = hsu_dma_desc_free;
+		vchan_init(&hsuc->vchan, &hsu->dma);
+
+		hsuc->direction = (i & 0x1) ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
+		hsuc->reg = addr + i * HSU_DMA_CHAN_LENGTH;
+	}
+
+	dma_cap_set(DMA_SLAVE, hsu->dma.cap_mask);
+	dma_cap_set(DMA_PRIVATE, hsu->dma.cap_mask);
+
+	hsu->dma.device_free_chan_resources = hsu_dma_free_chan_resources;
+
+	hsu->dma.device_prep_slave_sg = hsu_dma_prep_slave_sg;
+
+	hsu->dma.device_issue_pending = hsu_dma_issue_pending;
+	hsu->dma.device_tx_status = hsu_dma_tx_status;
+
+	hsu->dma.device_config = hsu_dma_slave_config;
+	hsu->dma.device_pause = hsu_dma_pause;
+	hsu->dma.device_resume = hsu_dma_resume;
+	hsu->dma.device_terminate_all = hsu_dma_terminate_all;
+	hsu->dma.device_synchronize = hsu_dma_synchronize;
+
+	hsu->dma.src_addr_widths = HSU_DMA_BUSWIDTHS;
+	hsu->dma.dst_addr_widths = HSU_DMA_BUSWIDTHS;
+	hsu->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	hsu->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+	hsu->dma.dev = chip->dev;
+
+	dma_set_max_seg_size(hsu->dma.dev, HSU_CH_DxTSR_MASK);
+
+	ret = dma_async_device_register(&hsu->dma);
+	if (ret)
+		return ret;
+
+	dev_info(chip->dev, "Found HSU DMA, %d channels\n", hsu->nr_channels);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_probe);
+
+int hsu_dma_remove(struct hsu_dma_chip *chip)
+{
+	struct hsu_dma *hsu = chip->hsu;
+	unsigned short i;
+
+	dma_async_device_unregister(&hsu->dma);
+
+	for (i = 0; i < hsu->nr_channels; i++) {
+		struct hsu_dma_chan *hsuc = &hsu->chan[i];
+
+		tasklet_kill(&hsuc->vchan.task);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_remove);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA core driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
diff --git a/drivers/dma/hsu/hsu.h b/drivers/dma/hsu/hsu.h
new file mode 100644
index 000000000..3bca577b9
--- /dev/null
+++ b/drivers/dma/hsu/hsu.h
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ */
+
+#ifndef __DMA_HSU_H__
+#define __DMA_HSU_H__
+
+#include <linux/bits.h>
+#include <linux/container_of.h>
+#include <linux/io.h>
+#include <linux/types.h>
+
+#include <linux/dma/hsu.h>
+
+#include "../virt-dma.h"
+
+#define HSU_CH_SR		0x00			/* channel status */
+#define HSU_CH_CR		0x04			/* channel control */
+#define HSU_CH_DCR		0x08			/* descriptor control */
+#define HSU_CH_BSR		0x10			/* FIFO buffer size */
+#define HSU_CH_MTSR		0x14			/* minimum transfer size */
+#define HSU_CH_DxSAR(x)		(0x20 + 8 * (x))	/* desc start addr */
+#define HSU_CH_DxTSR(x)		(0x24 + 8 * (x))	/* desc transfer size */
+#define HSU_CH_D0SAR		0x20			/* desc 0 start addr */
+#define HSU_CH_D0TSR		0x24			/* desc 0 transfer size */
+#define HSU_CH_D1SAR		0x28
+#define HSU_CH_D1TSR		0x2c
+#define HSU_CH_D2SAR		0x30
+#define HSU_CH_D2TSR		0x34
+#define HSU_CH_D3SAR		0x38
+#define HSU_CH_D3TSR		0x3c
+
+#define HSU_DMA_CHAN_NR_DESC	4
+#define HSU_DMA_CHAN_LENGTH	0x40
+
+/* Bits in HSU_CH_SR */
+#define HSU_CH_SR_DESCTO(x)	BIT(8 + (x))
+#define HSU_CH_SR_DESCTO_ANY	GENMASK(11, 8)
+#define HSU_CH_SR_CHE		BIT(15)
+#define HSU_CH_SR_DESCE(x)	BIT(16 + (x))
+#define HSU_CH_SR_DESCE_ANY	GENMASK(19, 16)
+#define HSU_CH_SR_CDESC_ANY	GENMASK(31, 30)
+
+/* Bits in HSU_CH_CR */
+#define HSU_CH_CR_CHA		BIT(0)
+#define HSU_CH_CR_CHD		BIT(1)
+
+/* Bits in HSU_CH_DCR */
+#define HSU_CH_DCR_DESCA(x)	BIT(0 + (x))
+#define HSU_CH_DCR_CHSOD(x)	BIT(8 + (x))
+#define HSU_CH_DCR_CHSOTO	BIT(14)
+#define HSU_CH_DCR_CHSOE	BIT(15)
+#define HSU_CH_DCR_CHDI(x)	BIT(16 + (x))
+#define HSU_CH_DCR_CHEI		BIT(23)
+#define HSU_CH_DCR_CHTOI(x)	BIT(24 + (x))
+
+/* Bits in HSU_CH_DxTSR */
+#define HSU_CH_DxTSR_MASK	GENMASK(15, 0)
+#define HSU_CH_DxTSR_TSR(x)	((x) & HSU_CH_DxTSR_MASK)
+
+struct hsu_dma_sg {
+	dma_addr_t addr;
+	unsigned int len;
+};
+
+struct hsu_dma_desc {
+	struct virt_dma_desc vdesc;
+	enum dma_transfer_direction direction;
+	struct hsu_dma_sg *sg;
+	unsigned int nents;
+	size_t length;
+	unsigned int active;
+	enum dma_status status;
+};
+
+static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
+{
+	return container_of(vdesc, struct hsu_dma_desc, vdesc);
+}
+
+struct hsu_dma_chan {
+	struct virt_dma_chan vchan;
+
+	void __iomem *reg;
+
+	/* hardware configuration */
+	enum dma_transfer_direction direction;
+	struct dma_slave_config config;
+
+	struct hsu_dma_desc *desc;
+};
+
+static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
+{
+	return container_of(chan, struct hsu_dma_chan, vchan.chan);
+}
+
+static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
+{
+	return readl(hsuc->reg + offset);
+}
+
+static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
+				   u32 value)
+{
+	writel(value, hsuc->reg + offset);
+}
+
+struct hsu_dma {
+	struct dma_device		dma;
+
+	/* channels */
+	struct hsu_dma_chan		*chan;
+	unsigned short			nr_channels;
+};
+
+static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
+{
+	return container_of(ddev, struct hsu_dma, dma);
+}
+
+#endif /* __DMA_HSU_H__ */
diff --git a/drivers/dma/hsu/pci.c b/drivers/dma/hsu/pci.c
new file mode 100644
index 000000000..0fcc0c0c2
--- /dev/null
+++ b/drivers/dma/hsu/pci.c
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCI driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "hsu.h"
+
+#define HSU_PCI_DMASR		0x00
+#define HSU_PCI_DMAISR		0x04
+
+#define HSU_PCI_CHAN_OFFSET	0x100
+
+#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA	0x081e
+#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA	0x1192
+
+static irqreturn_t hsu_pci_irq(int irq, void *dev)
+{
+	struct hsu_dma_chip *chip = dev;
+	unsigned long dmaisr;
+	unsigned short i;
+	u32 status;
+	int ret = 0;
+	int err;
+
+	dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
+	for_each_set_bit(i, &dmaisr, chip->hsu->nr_channels) {
+		err = hsu_dma_get_status(chip, i, &status);
+		if (err > 0)
+			ret |= 1;
+		else if (err == 0)
+			ret |= hsu_dma_do_irq(chip, i, status);
+	}
+
+	return IRQ_RETVAL(ret);
+}
+
+static void hsu_pci_dma_remove(void *chip)
+{
+	hsu_dma_remove(chip);
+}
+
+static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct device *dev = &pdev->dev;
+	struct hsu_dma_chip *chip;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
+	if (ret) {
+		dev_err(&pdev->dev, "I/O memory remapping failed\n");
+		return ret;
+	}
+
+	pci_set_master(pdev);
+	pci_try_set_mwi(pdev);
+
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return ret;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+	if (ret < 0)
+		return ret;
+
+	chip->dev = &pdev->dev;
+	chip->regs = pcim_iomap_table(pdev)[0];
+	chip->length = pci_resource_len(pdev, 0);
+	chip->offset = HSU_PCI_CHAN_OFFSET;
+	chip->irq = pci_irq_vector(pdev, 0);
+
+	ret = hsu_dma_probe(chip);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, hsu_pci_dma_remove, chip);
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(dev, chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
+	if (ret)
+		return ret;
+
+	/*
+	 * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
+	 * to have different numbers, is shared between HSU DMA and UART IPs.
+	 * Thus on such SoCs we are expecting that IRQ handler is called in
+	 * UART driver only. Instead of handling the spurious interrupt
+	 * from HSU DMA here and waste CPU time and delay HSU UART interrupt
+	 * handling, disable the interrupt entirely.
+	 */
+	if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
+		disable_irq_nosync(chip->irq);
+
+	pci_set_drvdata(pdev, chip);
+
+	return 0;
+}
+
+static const struct pci_device_id hsu_pci_id_table[] = {
+	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
+	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
+
+static struct pci_driver hsu_pci_driver = {
+	.name		= "hsu_dma_pci",
+	.id_table	= hsu_pci_id_table,
+	.probe		= hsu_pci_probe,
+};
+
+module_pci_driver(hsu_pci_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");