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, 608 insertions, 0 deletions

diff --git a/drivers/spi/spi-microchip-core.c b/drivers/spi/spi-microchip-core.c
new file mode 100644
index 000000000..aeaa1da88
--- /dev/null
+++ b/drivers/spi/spi-microchip-core.c
@@ -0,0 +1,608 @@
+// SPDX-License-Identifier: (GPL-2.0)
+/*
+ * Microchip CoreSPI SPI controller driver
+ *
+ * Copyright (c) 2018-2022 Microchip Technology Inc. and its subsidiaries
+ *
+ * Author: Daire McNamara <daire.mcnamara@microchip.com>
+ * Author: Conor Dooley <conor.dooley@microchip.com>
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+
+#define MAX_LEN				(0xffff)
+#define MAX_CS				(8)
+#define DEFAULT_FRAMESIZE		(8)
+#define FIFO_DEPTH			(32)
+#define CLK_GEN_MODE1_MAX		(255)
+#define CLK_GEN_MODE0_MAX		(15)
+#define CLK_GEN_MIN			(0)
+#define MODE_X_MASK_SHIFT		(24)
+
+#define CONTROL_ENABLE			BIT(0)
+#define CONTROL_MASTER			BIT(1)
+#define CONTROL_RX_DATA_INT		BIT(4)
+#define CONTROL_TX_DATA_INT		BIT(5)
+#define CONTROL_RX_OVER_INT		BIT(6)
+#define CONTROL_TX_UNDER_INT		BIT(7)
+#define CONTROL_SPO			BIT(24)
+#define CONTROL_SPH			BIT(25)
+#define CONTROL_SPS			BIT(26)
+#define CONTROL_FRAMEURUN		BIT(27)
+#define CONTROL_CLKMODE			BIT(28)
+#define CONTROL_BIGFIFO			BIT(29)
+#define CONTROL_OENOFF			BIT(30)
+#define CONTROL_RESET			BIT(31)
+
+#define CONTROL_MODE_MASK		GENMASK(3, 2)
+#define  MOTOROLA_MODE			(0)
+#define CONTROL_FRAMECNT_MASK		GENMASK(23, 8)
+#define CONTROL_FRAMECNT_SHIFT		(8)
+
+#define STATUS_ACTIVE			BIT(14)
+#define STATUS_SSEL			BIT(13)
+#define STATUS_FRAMESTART		BIT(12)
+#define STATUS_TXFIFO_EMPTY_NEXT_READ	BIT(11)
+#define STATUS_TXFIFO_EMPTY		BIT(10)
+#define STATUS_TXFIFO_FULL_NEXT_WRITE	BIT(9)
+#define STATUS_TXFIFO_FULL		BIT(8)
+#define STATUS_RXFIFO_EMPTY_NEXT_READ	BIT(7)
+#define STATUS_RXFIFO_EMPTY		BIT(6)
+#define STATUS_RXFIFO_FULL_NEXT_WRITE	BIT(5)
+#define STATUS_RXFIFO_FULL		BIT(4)
+#define STATUS_TX_UNDERRUN		BIT(3)
+#define STATUS_RX_OVERFLOW		BIT(2)
+#define STATUS_RXDAT_RXED		BIT(1)
+#define STATUS_TXDAT_SENT		BIT(0)
+
+#define INT_TXDONE			BIT(0)
+#define INT_RXRDY			BIT(1)
+#define INT_RX_CHANNEL_OVERFLOW		BIT(2)
+#define INT_TX_CHANNEL_UNDERRUN		BIT(3)
+
+#define INT_ENABLE_MASK (CONTROL_RX_DATA_INT | CONTROL_TX_DATA_INT | \
+			 CONTROL_RX_OVER_INT | CONTROL_TX_UNDER_INT)
+
+#define REG_CONTROL		(0x00)
+#define REG_FRAME_SIZE		(0x04)
+#define REG_STATUS		(0x08)
+#define REG_INT_CLEAR		(0x0c)
+#define REG_RX_DATA		(0x10)
+#define REG_TX_DATA		(0x14)
+#define REG_CLK_GEN		(0x18)
+#define REG_SLAVE_SELECT	(0x1c)
+#define  SSEL_MASK		GENMASK(7, 0)
+#define  SSEL_DIRECT		BIT(8)
+#define  SSELOUT_SHIFT		9
+#define  SSELOUT		BIT(SSELOUT_SHIFT)
+#define REG_MIS			(0x20)
+#define REG_RIS			(0x24)
+#define REG_CONTROL2		(0x28)
+#define REG_COMMAND		(0x2c)
+#define REG_PKTSIZE		(0x30)
+#define REG_CMD_SIZE		(0x34)
+#define REG_HWSTATUS		(0x38)
+#define REG_STAT8		(0x3c)
+#define REG_CTRL2		(0x48)
+#define REG_FRAMESUP		(0x50)
+
+struct mchp_corespi {
+	void __iomem *regs;
+	struct clk *clk;
+	const u8 *tx_buf;
+	u8 *rx_buf;
+	u32 clk_gen; /* divider for spi output clock generated by the controller */
+	u32 clk_mode;
+	int irq;
+	int tx_len;
+	int rx_len;
+	int pending;
+};
+
+static inline u32 mchp_corespi_read(struct mchp_corespi *spi, unsigned int reg)
+{
+	return readl(spi->regs + reg);
+}
+
+static inline void mchp_corespi_write(struct mchp_corespi *spi, unsigned int reg, u32 val)
+{
+	writel(val, spi->regs + reg);
+}
+
+static inline void mchp_corespi_disable(struct mchp_corespi *spi)
+{
+	u32 control = mchp_corespi_read(spi, REG_CONTROL);
+
+	control &= ~CONTROL_ENABLE;
+
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static inline void mchp_corespi_read_fifo(struct mchp_corespi *spi)
+{
+	u8 data;
+	int fifo_max, i = 0;
+
+	fifo_max = min(spi->rx_len, FIFO_DEPTH);
+
+	while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_RXFIFO_EMPTY)) {
+		data = mchp_corespi_read(spi, REG_RX_DATA);
+
+		if (spi->rx_buf)
+			*spi->rx_buf++ = data;
+		i++;
+	}
+	spi->rx_len -= i;
+	spi->pending -= i;
+}
+
+static void mchp_corespi_enable_ints(struct mchp_corespi *spi)
+{
+	u32 control, mask = INT_ENABLE_MASK;
+
+	mchp_corespi_disable(spi);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+
+	control |= mask;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+
+	control |= CONTROL_ENABLE;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static void mchp_corespi_disable_ints(struct mchp_corespi *spi)
+{
+	u32 control, mask = INT_ENABLE_MASK;
+
+	mchp_corespi_disable(spi);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	control &= ~mask;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+
+	control |= CONTROL_ENABLE;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static inline void mchp_corespi_set_xfer_size(struct mchp_corespi *spi, int len)
+{
+	u32 control;
+	u16 lenpart;
+
+	/*
+	 * Disable the SPI controller. Writes to transfer length have
+	 * no effect when the controller is enabled.
+	 */
+	mchp_corespi_disable(spi);
+
+	/*
+	 * The lower 16 bits of the frame count are stored in the control reg
+	 * for legacy reasons, but the upper 16 written to a different register:
+	 * FRAMESUP. While both the upper and lower bits can be *READ* from the
+	 * FRAMESUP register, writing to the lower 16 bits is a NOP
+	 */
+	lenpart = len & 0xffff;
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	control &= ~CONTROL_FRAMECNT_MASK;
+	control |= lenpart << CONTROL_FRAMECNT_SHIFT;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+
+	lenpart = len & 0xffff0000;
+	mchp_corespi_write(spi, REG_FRAMESUP, lenpart);
+
+	control |= CONTROL_ENABLE;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static inline void mchp_corespi_write_fifo(struct mchp_corespi *spi)
+{
+	u8 byte;
+	int fifo_max, i = 0;
+
+	fifo_max = min(spi->tx_len, FIFO_DEPTH);
+	mchp_corespi_set_xfer_size(spi, fifo_max);
+
+	while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_TXFIFO_FULL)) {
+		byte = spi->tx_buf ? *spi->tx_buf++ : 0xaa;
+		mchp_corespi_write(spi, REG_TX_DATA, byte);
+		i++;
+	}
+
+	spi->tx_len -= i;
+	spi->pending += i;
+}
+
+static inline void mchp_corespi_set_framesize(struct mchp_corespi *spi, int bt)
+{
+	u32 control;
+
+	/*
+	 * Disable the SPI controller. Writes to the frame size have
+	 * no effect when the controller is enabled.
+	 */
+	mchp_corespi_disable(spi);
+
+	mchp_corespi_write(spi, REG_FRAME_SIZE, bt);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	control |= CONTROL_ENABLE;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static void mchp_corespi_set_cs(struct spi_device *spi, bool disable)
+{
+	u32 reg;
+	struct mchp_corespi *corespi = spi_master_get_devdata(spi->master);
+
+	reg = mchp_corespi_read(corespi, REG_SLAVE_SELECT);
+	reg &= ~BIT(spi->chip_select);
+	reg |= !disable << spi->chip_select;
+
+	mchp_corespi_write(corespi, REG_SLAVE_SELECT, reg);
+}
+
+static int mchp_corespi_setup(struct spi_device *spi)
+{
+	struct mchp_corespi *corespi = spi_master_get_devdata(spi->master);
+	u32 reg;
+
+	/*
+	 * Active high slaves need to be specifically set to their inactive
+	 * states during probe by adding them to the "control group" & thus
+	 * driving their select line low.
+	 */
+	if (spi->mode & SPI_CS_HIGH) {
+		reg = mchp_corespi_read(corespi, REG_SLAVE_SELECT);
+		reg |= BIT(spi->chip_select);
+		mchp_corespi_write(corespi, REG_SLAVE_SELECT, reg);
+	}
+	return 0;
+}
+
+static void mchp_corespi_init(struct spi_master *master, struct mchp_corespi *spi)
+{
+	unsigned long clk_hz;
+	u32 control = mchp_corespi_read(spi, REG_CONTROL);
+
+	control |= CONTROL_MASTER;
+
+	control &= ~CONTROL_MODE_MASK;
+	control |= MOTOROLA_MODE;
+
+	mchp_corespi_set_framesize(spi, DEFAULT_FRAMESIZE);
+
+	/* max. possible spi clock rate is the apb clock rate */
+	clk_hz = clk_get_rate(spi->clk);
+	master->max_speed_hz = clk_hz;
+
+	/*
+	 * The controller must be configured so that it doesn't remove Chip
+	 * Select until the entire message has been transferred, even if at
+	 * some points TX FIFO becomes empty.
+	 *
+	 * BIGFIFO mode is also enabled, which sets the fifo depth to 32 frames
+	 * for the 8 bit transfers that this driver uses.
+	 */
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	control |= CONTROL_SPS | CONTROL_BIGFIFO;
+
+	mchp_corespi_write(spi, REG_CONTROL, control);
+
+	mchp_corespi_enable_ints(spi);
+
+	/*
+	 * It is required to enable direct mode, otherwise control over the chip
+	 * select is relinquished to the hardware. SSELOUT is enabled too so we
+	 * can deal with active high slaves.
+	 */
+	mchp_corespi_write(spi, REG_SLAVE_SELECT, SSELOUT | SSEL_DIRECT);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+
+	control &= ~CONTROL_RESET;
+	control |= CONTROL_ENABLE;
+
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static inline void mchp_corespi_set_clk_gen(struct mchp_corespi *spi)
+{
+	u32 control;
+
+	mchp_corespi_disable(spi);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	if (spi->clk_mode)
+		control |= CONTROL_CLKMODE;
+	else
+		control &= ~CONTROL_CLKMODE;
+
+	mchp_corespi_write(spi, REG_CLK_GEN, spi->clk_gen);
+	mchp_corespi_write(spi, REG_CONTROL, control);
+	mchp_corespi_write(spi, REG_CONTROL, control | CONTROL_ENABLE);
+}
+
+static inline void mchp_corespi_set_mode(struct mchp_corespi *spi, unsigned int mode)
+{
+	u32 control, mode_val;
+
+	switch (mode & SPI_MODE_X_MASK) {
+	case SPI_MODE_0:
+		mode_val = 0;
+		break;
+	case SPI_MODE_1:
+		mode_val = CONTROL_SPH;
+		break;
+	case SPI_MODE_2:
+		mode_val = CONTROL_SPO;
+		break;
+	case SPI_MODE_3:
+		mode_val = CONTROL_SPH | CONTROL_SPO;
+		break;
+	}
+
+	/*
+	 * Disable the SPI controller. Writes to the frame size have
+	 * no effect when the controller is enabled.
+	 */
+	mchp_corespi_disable(spi);
+
+	control = mchp_corespi_read(spi, REG_CONTROL);
+	control &= ~(SPI_MODE_X_MASK << MODE_X_MASK_SHIFT);
+	control |= mode_val;
+
+	mchp_corespi_write(spi, REG_CONTROL, control);
+
+	control |= CONTROL_ENABLE;
+	mchp_corespi_write(spi, REG_CONTROL, control);
+}
+
+static irqreturn_t mchp_corespi_interrupt(int irq, void *dev_id)
+{
+	struct spi_master *master = dev_id;
+	struct mchp_corespi *spi = spi_master_get_devdata(master);
+	u32 intfield = mchp_corespi_read(spi, REG_MIS) & 0xf;
+	bool finalise = false;
+
+	/* Interrupt line may be shared and not for us at all */
+	if (intfield == 0)
+		return IRQ_NONE;
+
+	if (intfield & INT_TXDONE) {
+		mchp_corespi_write(spi, REG_INT_CLEAR, INT_TXDONE);
+
+		if (spi->rx_len)
+			mchp_corespi_read_fifo(spi);
+
+		if (spi->tx_len)
+			mchp_corespi_write_fifo(spi);
+
+		if (!spi->rx_len)
+			finalise = true;
+	}
+
+	if (intfield & INT_RXRDY)
+		mchp_corespi_write(spi, REG_INT_CLEAR, INT_RXRDY);
+
+	if (intfield & INT_RX_CHANNEL_OVERFLOW) {
+		mchp_corespi_write(spi, REG_INT_CLEAR, INT_RX_CHANNEL_OVERFLOW);
+		finalise = true;
+		dev_err(&master->dev,
+			"%s: RX OVERFLOW: rxlen: %d, txlen: %d\n", __func__,
+			spi->rx_len, spi->tx_len);
+	}
+
+	if (intfield & INT_TX_CHANNEL_UNDERRUN) {
+		mchp_corespi_write(spi, REG_INT_CLEAR, INT_TX_CHANNEL_UNDERRUN);
+		finalise = true;
+		dev_err(&master->dev,
+			"%s: TX UNDERFLOW: rxlen: %d, txlen: %d\n", __func__,
+			spi->rx_len, spi->tx_len);
+	}
+
+	if (finalise)
+		spi_finalize_current_transfer(master);
+
+	return IRQ_HANDLED;
+}
+
+static int mchp_corespi_calculate_clkgen(struct mchp_corespi *spi,
+					 unsigned long target_hz)
+{
+	unsigned long clk_hz, spi_hz, clk_gen;
+
+	clk_hz = clk_get_rate(spi->clk);
+	if (!clk_hz)
+		return -EINVAL;
+	spi_hz = min(target_hz, clk_hz);
+
+	/*
+	 * There are two possible clock modes for the controller generated
+	 * clock's division ratio:
+	 * CLK_MODE = 0: 1 / (2^(CLK_GEN + 1)) where CLK_GEN = 0 to 15.
+	 * CLK_MODE = 1: 1 / (2 * CLK_GEN + 1) where CLK_GEN = 0 to 255.
+	 * First try mode 1, fall back to 0 and if we have tried both modes and
+	 * we /still/ can't get a good setting, we then throw the toys out of
+	 * the pram and give up
+	 * clk_gen is the register name for the clock divider on MPFS.
+	 */
+	clk_gen = DIV_ROUND_UP(clk_hz, 2 * spi_hz) - 1;
+	if (clk_gen > CLK_GEN_MODE1_MAX || clk_gen <= CLK_GEN_MIN) {
+		clk_gen = DIV_ROUND_UP(clk_hz, spi_hz);
+		clk_gen = fls(clk_gen) - 1;
+
+		if (clk_gen > CLK_GEN_MODE0_MAX)
+			return -EINVAL;
+
+		spi->clk_mode = 0;
+	} else {
+		spi->clk_mode = 1;
+	}
+
+	spi->clk_gen = clk_gen;
+	return 0;
+}
+
+static int mchp_corespi_transfer_one(struct spi_master *master,
+				     struct spi_device *spi_dev,
+				     struct spi_transfer *xfer)
+{
+	struct mchp_corespi *spi = spi_master_get_devdata(master);
+	int ret;
+
+	ret = mchp_corespi_calculate_clkgen(spi, (unsigned long)xfer->speed_hz);
+	if (ret) {
+		dev_err(&master->dev, "failed to set clk_gen for target %u Hz\n", xfer->speed_hz);
+		return ret;
+	}
+
+	mchp_corespi_set_clk_gen(spi);
+
+	spi->tx_buf = xfer->tx_buf;
+	spi->rx_buf = xfer->rx_buf;
+	spi->tx_len = xfer->len;
+	spi->rx_len = xfer->len;
+	spi->pending = 0;
+
+	mchp_corespi_set_xfer_size(spi, (spi->tx_len > FIFO_DEPTH)
+				   ? FIFO_DEPTH : spi->tx_len);
+
+	if (spi->tx_len)
+		mchp_corespi_write_fifo(spi);
+	return 1;
+}
+
+static int mchp_corespi_prepare_message(struct spi_master *master,
+					struct spi_message *msg)
+{
+	struct spi_device *spi_dev = msg->spi;
+	struct mchp_corespi *spi = spi_master_get_devdata(master);
+
+	mchp_corespi_set_framesize(spi, DEFAULT_FRAMESIZE);
+	mchp_corespi_set_mode(spi, spi_dev->mode);
+
+	return 0;
+}
+
+static int mchp_corespi_probe(struct platform_device *pdev)
+{
+	struct spi_master *master;
+	struct mchp_corespi *spi;
+	struct resource *res;
+	u32 num_cs;
+	int ret = 0;
+
+	master = devm_spi_alloc_master(&pdev->dev, sizeof(*spi));
+	if (!master)
+		return dev_err_probe(&pdev->dev, -ENOMEM,
+				     "unable to allocate master for SPI controller\n");
+
+	platform_set_drvdata(pdev, master);
+
+	if (of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs))
+		num_cs = MAX_CS;
+
+	master->num_chipselect = num_cs;
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+	master->setup = mchp_corespi_setup;
+	master->bits_per_word_mask = SPI_BPW_MASK(8);
+	master->transfer_one = mchp_corespi_transfer_one;
+	master->prepare_message = mchp_corespi_prepare_message;
+	master->set_cs = mchp_corespi_set_cs;
+	master->dev.of_node = pdev->dev.of_node;
+
+	spi = spi_master_get_devdata(master);
+
+	spi->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+	if (IS_ERR(spi->regs))
+		return PTR_ERR(spi->regs);
+
+	spi->irq = platform_get_irq(pdev, 0);
+	if (spi->irq <= 0)
+		return dev_err_probe(&pdev->dev, -ENXIO,
+				     "invalid IRQ %d for SPI controller\n",
+				     spi->irq);
+
+	ret = devm_request_irq(&pdev->dev, spi->irq, mchp_corespi_interrupt,
+			       IRQF_SHARED, dev_name(&pdev->dev), master);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "could not request irq\n");
+
+	spi->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(spi->clk))
+		return dev_err_probe(&pdev->dev, PTR_ERR(spi->clk),
+				     "could not get clk\n");
+
+	ret = clk_prepare_enable(spi->clk);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "failed to enable clock\n");
+
+	mchp_corespi_init(master, spi);
+
+	ret = devm_spi_register_master(&pdev->dev, master);
+	if (ret) {
+		mchp_corespi_disable(spi);
+		clk_disable_unprepare(spi->clk);
+		return dev_err_probe(&pdev->dev, ret,
+				     "unable to register master for SPI controller\n");
+	}
+
+	dev_info(&pdev->dev, "Registered SPI controller %d\n", master->bus_num);
+
+	return 0;
+}
+
+static int mchp_corespi_remove(struct platform_device *pdev)
+{
+	struct spi_master *master  = platform_get_drvdata(pdev);
+	struct mchp_corespi *spi = spi_master_get_devdata(master);
+
+	mchp_corespi_disable_ints(spi);
+	clk_disable_unprepare(spi->clk);
+	mchp_corespi_disable(spi);
+
+	return 0;
+}
+
+#define MICROCHIP_SPI_PM_OPS (NULL)
+
+/*
+ * Platform driver data structure
+ */
+
+#if defined(CONFIG_OF)
+static const struct of_device_id mchp_corespi_dt_ids[] = {
+	{ .compatible = "microchip,mpfs-spi" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mchp_corespi_dt_ids);
+#endif
+
+static struct platform_driver mchp_corespi_driver = {
+	.probe = mchp_corespi_probe,
+	.driver = {
+		.name = "microchip-corespi",
+		.pm = MICROCHIP_SPI_PM_OPS,
+		.of_match_table = of_match_ptr(mchp_corespi_dt_ids),
+	},
+	.remove = mchp_corespi_remove,
+};
+module_platform_driver(mchp_corespi_driver);
+MODULE_DESCRIPTION("Microchip coreSPI SPI controller driver");
+MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
+MODULE_LICENSE("GPL");