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, 884 insertions, 0 deletions

diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
new file mode 100644
index 000000000..1e08704d5
--- /dev/null
+++ b/drivers/ata/ahci_xgene.c
@@ -0,0 +1,884 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AppliedMicro X-Gene SoC SATA Host Controller Driver
+ *
+ * Copyright (c) 2014, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ *         Tuan Phan <tphan@apm.com>
+ *         Suman Tripathi <stripathi@apm.com>
+ *
+ * NOTE: PM support is not currently available.
+ */
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/ahci_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/phy/phy.h>
+#include "ahci.h"
+
+#define DRV_NAME "xgene-ahci"
+
+/* Max # of disk per a controller */
+#define MAX_AHCI_CHN_PERCTR		2
+
+/* MUX CSR */
+#define SATA_ENET_CONFIG_REG		0x00000000
+#define  CFG_SATA_ENET_SELECT_MASK	0x00000001
+
+/* SATA core host controller CSR */
+#define SLVRDERRATTRIBUTES		0x00000000
+#define SLVWRERRATTRIBUTES		0x00000004
+#define MSTRDERRATTRIBUTES		0x00000008
+#define MSTWRERRATTRIBUTES		0x0000000c
+#define BUSCTLREG			0x00000014
+#define IOFMSTRWAUX			0x00000018
+#define INTSTATUSMASK			0x0000002c
+#define ERRINTSTATUS			0x00000030
+#define ERRINTSTATUSMASK		0x00000034
+
+/* SATA host AHCI CSR */
+#define PORTCFG				0x000000a4
+#define  PORTADDR_SET(dst, src) \
+		(((dst) & ~0x0000003f) | (((u32)(src)) & 0x0000003f))
+#define PORTPHY1CFG		0x000000a8
+#define PORTPHY1CFG_FRCPHYRDY_SET(dst, src) \
+		(((dst) & ~0x00100000) | (((u32)(src) << 0x14) & 0x00100000))
+#define PORTPHY2CFG			0x000000ac
+#define PORTPHY3CFG			0x000000b0
+#define PORTPHY4CFG			0x000000b4
+#define PORTPHY5CFG			0x000000b8
+#define SCTL0				0x0000012C
+#define PORTPHY5CFG_RTCHG_SET(dst, src) \
+		(((dst) & ~0xfff00000) | (((u32)(src) << 0x14) & 0xfff00000))
+#define PORTAXICFG_EN_CONTEXT_SET(dst, src) \
+		(((dst) & ~0x01000000) | (((u32)(src) << 0x18) & 0x01000000))
+#define PORTAXICFG			0x000000bc
+#define PORTAXICFG_OUTTRANS_SET(dst, src) \
+		(((dst) & ~0x00f00000) | (((u32)(src) << 0x14) & 0x00f00000))
+#define PORTRANSCFG			0x000000c8
+#define PORTRANSCFG_RXWM_SET(dst, src)		\
+		(((dst) & ~0x0000007f) | (((u32)(src)) & 0x0000007f))
+
+/* SATA host controller AXI CSR */
+#define INT_SLV_TMOMASK			0x00000010
+
+/* SATA diagnostic CSR */
+#define CFG_MEM_RAM_SHUTDOWN		0x00000070
+#define BLOCK_MEM_RDY			0x00000074
+
+/* Max retry for link down */
+#define MAX_LINK_DOWN_RETRY 3
+
+enum xgene_ahci_version {
+	XGENE_AHCI_V1 = 1,
+	XGENE_AHCI_V2,
+};
+
+struct xgene_ahci_context {
+	struct ahci_host_priv *hpriv;
+	struct device *dev;
+	u8 last_cmd[MAX_AHCI_CHN_PERCTR]; /* tracking the last command issued*/
+	u32 class[MAX_AHCI_CHN_PERCTR]; /* tracking the class of device */
+	void __iomem *csr_core;		/* Core CSR address of IP */
+	void __iomem *csr_diag;		/* Diag CSR address of IP */
+	void __iomem *csr_axi;		/* AXI CSR address of IP */
+	void __iomem *csr_mux;		/* MUX CSR address of IP */
+};
+
+static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
+{
+	dev_dbg(ctx->dev, "Release memory from shutdown\n");
+	writel(0x0, ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN);
+	readl(ctx->csr_diag + CFG_MEM_RAM_SHUTDOWN); /* Force a barrier */
+	msleep(1);	/* reset may take up to 1ms */
+	if (readl(ctx->csr_diag + BLOCK_MEM_RDY) != 0xFFFFFFFF) {
+		dev_err(ctx->dev, "failed to release memory from shutdown\n");
+		return -ENODEV;
+	}
+	return 0;
+}
+
+/**
+ * xgene_ahci_poll_reg_val- Poll a register on a specific value.
+ * @ap : ATA port of interest.
+ * @reg : Register of interest.
+ * @val : Value to be attained.
+ * @interval : waiting interval for polling.
+ * @timeout : timeout for achieving the value.
+ */
+static int xgene_ahci_poll_reg_val(struct ata_port *ap,
+				   void __iomem *reg, unsigned
+				   int val, unsigned long interval,
+				   unsigned long timeout)
+{
+	unsigned long deadline;
+	unsigned int tmp;
+
+	tmp = ioread32(reg);
+	deadline = ata_deadline(jiffies, timeout);
+
+	while (tmp != val && time_before(jiffies, deadline)) {
+		ata_msleep(ap, interval);
+		tmp = ioread32(reg);
+	}
+
+	return tmp;
+}
+
+/**
+ * xgene_ahci_restart_engine - Restart the dma engine.
+ * @ap : ATA port of interest
+ *
+ * Waits for completion of multiple commands and restarts
+ * the DMA engine inside the controller.
+ */
+static int xgene_ahci_restart_engine(struct ata_port *ap)
+{
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	struct ahci_port_priv *pp = ap->private_data;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	u32 fbs;
+
+	/*
+	 * In case of PMP multiple IDENTIFY DEVICE commands can be
+	 * issued inside PxCI. So need to poll PxCI for the
+	 * completion of outstanding IDENTIFY DEVICE commands before
+	 * we restart the DMA engine.
+	 */
+	if (xgene_ahci_poll_reg_val(ap, port_mmio +
+				    PORT_CMD_ISSUE, 0x0, 1, 100))
+		  return -EBUSY;
+
+	hpriv->stop_engine(ap);
+	ahci_start_fis_rx(ap);
+
+	/*
+	 * Enable the PxFBS.FBS_EN bit as it
+	 * gets cleared due to stopping the engine.
+	 */
+	if (pp->fbs_supported) {
+		fbs = readl(port_mmio + PORT_FBS);
+		writel(fbs | PORT_FBS_EN, port_mmio + PORT_FBS);
+		fbs = readl(port_mmio + PORT_FBS);
+	}
+
+	hpriv->start_engine(ap);
+
+	return 0;
+}
+
+/**
+ * xgene_ahci_qc_issue - Issue commands to the device
+ * @qc: Command to issue
+ *
+ * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot
+ * clear the BSY bit after receiving the PIO setup FIS. This results in the dma
+ * state machine goes into the CMFatalErrorUpdate state and locks up. By
+ * restarting the dma engine, it removes the controller out of lock up state.
+ *
+ * Due to H/W errata, the controller is unable to save the PMP
+ * field fetched from command header before sending the H2D FIS.
+ * When the device returns the PMP port field in the D2H FIS, there is
+ * a mismatch and results in command completion failure. The
+ * workaround is to write the pmp value to PxFBS.DEV field before issuing
+ * any command to PMP.
+ */
+static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
+{
+	struct ata_port *ap = qc->ap;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	struct xgene_ahci_context *ctx = hpriv->plat_data;
+	int rc = 0;
+	u32 port_fbs;
+	void __iomem *port_mmio = ahci_port_base(ap);
+
+	/*
+	 * Write the pmp value to PxFBS.DEV
+	 * for case of Port Mulitplier.
+	 */
+	if (ctx->class[ap->port_no] == ATA_DEV_PMP) {
+		port_fbs = readl(port_mmio + PORT_FBS);
+		port_fbs &= ~PORT_FBS_DEV_MASK;
+		port_fbs |= qc->dev->link->pmp << PORT_FBS_DEV_OFFSET;
+		writel(port_fbs, port_mmio + PORT_FBS);
+	}
+
+	if (unlikely((ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA) ||
+	    (ctx->last_cmd[ap->port_no] == ATA_CMD_PACKET) ||
+	    (ctx->last_cmd[ap->port_no] == ATA_CMD_SMART)))
+		xgene_ahci_restart_engine(ap);
+
+	rc = ahci_qc_issue(qc);
+
+	/* Save the last command issued */
+	ctx->last_cmd[ap->port_no] = qc->tf.command;
+
+	return rc;
+}
+
+static bool xgene_ahci_is_memram_inited(struct xgene_ahci_context *ctx)
+{
+	void __iomem *diagcsr = ctx->csr_diag;
+
+	return (readl(diagcsr + CFG_MEM_RAM_SHUTDOWN) == 0 &&
+	        readl(diagcsr + BLOCK_MEM_RDY) == 0xFFFFFFFF);
+}
+
+/**
+ * xgene_ahci_read_id - Read ID data from the specified device
+ * @dev: device
+ * @tf: proposed taskfile
+ * @id: data buffer
+ *
+ * This custom read ID function is required due to the fact that the HW
+ * does not support DEVSLP.
+ */
+static unsigned int xgene_ahci_read_id(struct ata_device *dev,
+				       struct ata_taskfile *tf, __le16 *id)
+{
+	u32 err_mask;
+
+	err_mask = ata_do_dev_read_id(dev, tf, id);
+	if (err_mask)
+		return err_mask;
+
+	/*
+	 * Mask reserved area. Word78 spec of Link Power Management
+	 * bit15-8: reserved
+	 * bit7: NCQ autosence
+	 * bit6: Software settings preservation supported
+	 * bit5: reserved
+	 * bit4: In-order sata delivery supported
+	 * bit3: DIPM requests supported
+	 * bit2: DMA Setup FIS Auto-Activate optimization supported
+	 * bit1: DMA Setup FIX non-Zero buffer offsets supported
+	 * bit0: Reserved
+	 *
+	 * Clear reserved bit 8 (DEVSLP bit) as we don't support DEVSLP
+	 */
+	id[ATA_ID_FEATURE_SUPP] &= cpu_to_le16(~(1 << 8));
+
+	return 0;
+}
+
+static void xgene_ahci_set_phy_cfg(struct xgene_ahci_context *ctx, int channel)
+{
+	void __iomem *mmio = ctx->hpriv->mmio;
+	u32 val;
+
+	dev_dbg(ctx->dev, "port configure mmio 0x%p channel %d\n",
+		mmio, channel);
+	val = readl(mmio + PORTCFG);
+	val = PORTADDR_SET(val, channel == 0 ? 2 : 3);
+	writel(val, mmio + PORTCFG);
+	readl(mmio + PORTCFG);  /* Force a barrier */
+	/* Disable fix rate */
+	writel(0x0001fffe, mmio + PORTPHY1CFG);
+	readl(mmio + PORTPHY1CFG); /* Force a barrier */
+	writel(0x28183219, mmio + PORTPHY2CFG);
+	readl(mmio + PORTPHY2CFG); /* Force a barrier */
+	writel(0x13081008, mmio + PORTPHY3CFG);
+	readl(mmio + PORTPHY3CFG); /* Force a barrier */
+	writel(0x00480815, mmio + PORTPHY4CFG);
+	readl(mmio + PORTPHY4CFG); /* Force a barrier */
+	/* Set window negotiation */
+	val = readl(mmio + PORTPHY5CFG);
+	val = PORTPHY5CFG_RTCHG_SET(val, 0x300);
+	writel(val, mmio + PORTPHY5CFG);
+	readl(mmio + PORTPHY5CFG); /* Force a barrier */
+	val = readl(mmio + PORTAXICFG);
+	val = PORTAXICFG_EN_CONTEXT_SET(val, 0x1); /* Enable context mgmt */
+	val = PORTAXICFG_OUTTRANS_SET(val, 0xe); /* Set outstanding */
+	writel(val, mmio + PORTAXICFG);
+	readl(mmio + PORTAXICFG); /* Force a barrier */
+	/* Set the watermark threshold of the receive FIFO */
+	val = readl(mmio + PORTRANSCFG);
+	val = PORTRANSCFG_RXWM_SET(val, 0x30);
+	writel(val, mmio + PORTRANSCFG);
+}
+
+/**
+ * xgene_ahci_do_hardreset - Issue the actual COMRESET
+ * @link: link to reset
+ * @deadline: deadline jiffies for the operation
+ * @online: Return value to indicate if device online
+ *
+ * Due to the limitation of the hardware PHY, a difference set of setting is
+ * required for each supported disk speed - Gen3 (6.0Gbps), Gen2 (3.0Gbps),
+ * and Gen1 (1.5Gbps). Otherwise during long IO stress test, the PHY will
+ * report disparity error and etc. In addition, during COMRESET, there can
+ * be error reported in the register PORT_SCR_ERR. For SERR_DISPARITY and
+ * SERR_10B_8B_ERR, the PHY receiver line must be reseted. Also during long
+ * reboot cycle regression, sometimes the PHY reports link down even if the
+ * device is present because of speed negotiation failure. so need to retry
+ * the COMRESET to get the link up. The following algorithm is followed to
+ * proper configure the hardware PHY during COMRESET:
+ *
+ * Alg Part 1:
+ * 1. Start the PHY at Gen3 speed (default setting)
+ * 2. Issue the COMRESET
+ * 3. If no link, go to Alg Part 3
+ * 4. If link up, determine if the negotiated speed matches the PHY
+ *    configured speed
+ * 5. If they matched, go to Alg Part 2
+ * 6. If they do not matched and first time, configure the PHY for the linked
+ *    up disk speed and repeat step 2
+ * 7. Go to Alg Part 2
+ *
+ * Alg Part 2:
+ * 1. On link up, if there are any SERR_DISPARITY and SERR_10B_8B_ERR error
+ *    reported in the register PORT_SCR_ERR, then reset the PHY receiver line
+ * 2. Go to Alg Part 4
+ *
+ * Alg Part 3:
+ * 1. Check the PORT_SCR_STAT to see whether device presence detected but PHY
+ *    communication establishment failed and maximum link down attempts are
+ *    less than Max attempts 3 then goto Alg Part 1.
+ * 2. Go to Alg Part 4.
+ *
+ * Alg Part 4:
+ * 1. Clear any pending from register PORT_SCR_ERR.
+ *
+ * NOTE: For the initial version, we will NOT support Gen1/Gen2. In addition
+ *       and until the underlying PHY supports an method to reset the receiver
+ *       line, on detection of SERR_DISPARITY or SERR_10B_8B_ERR errors,
+ *       an warning message will be printed.
+ */
+static int xgene_ahci_do_hardreset(struct ata_link *link,
+				   unsigned long deadline, bool *online)
+{
+	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
+	struct ata_port *ap = link->ap;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	struct xgene_ahci_context *ctx = hpriv->plat_data;
+	struct ahci_port_priv *pp = ap->private_data;
+	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	struct ata_taskfile tf;
+	int link_down_retry = 0;
+	int rc;
+	u32 val, sstatus;
+
+	do {
+		/* clear D2H reception area to properly wait for D2H FIS */
+		ata_tf_init(link->device, &tf);
+		tf.status = ATA_BUSY;
+		ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+		rc = sata_link_hardreset(link, timing, deadline, online,
+				 ahci_check_ready);
+		if (*online) {
+			val = readl(port_mmio + PORT_SCR_ERR);
+			if (val & (SERR_DISPARITY | SERR_10B_8B_ERR))
+				dev_warn(ctx->dev, "link has error\n");
+			break;
+		}
+
+		sata_scr_read(link, SCR_STATUS, &sstatus);
+	} while (link_down_retry++ < MAX_LINK_DOWN_RETRY &&
+		 (sstatus & 0xff) == 0x1);
+
+	/* clear all errors if any pending */
+	val = readl(port_mmio + PORT_SCR_ERR);
+	writel(val, port_mmio + PORT_SCR_ERR);
+
+	return rc;
+}
+
+static int xgene_ahci_hardreset(struct ata_link *link, unsigned int *class,
+				unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+        struct ahci_host_priv *hpriv = ap->host->private_data;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	bool online;
+	int rc;
+	u32 portcmd_saved;
+	u32 portclb_saved;
+	u32 portclbhi_saved;
+	u32 portrxfis_saved;
+	u32 portrxfishi_saved;
+
+	/* As hardreset resets these CSR, save it to restore later */
+	portcmd_saved = readl(port_mmio + PORT_CMD);
+	portclb_saved = readl(port_mmio + PORT_LST_ADDR);
+	portclbhi_saved = readl(port_mmio + PORT_LST_ADDR_HI);
+	portrxfis_saved = readl(port_mmio + PORT_FIS_ADDR);
+	portrxfishi_saved = readl(port_mmio + PORT_FIS_ADDR_HI);
+
+	hpriv->stop_engine(ap);
+
+	rc = xgene_ahci_do_hardreset(link, deadline, &online);
+
+	/* As controller hardreset clears them, restore them */
+	writel(portcmd_saved, port_mmio + PORT_CMD);
+	writel(portclb_saved, port_mmio + PORT_LST_ADDR);
+	writel(portclbhi_saved, port_mmio + PORT_LST_ADDR_HI);
+	writel(portrxfis_saved, port_mmio + PORT_FIS_ADDR);
+	writel(portrxfishi_saved, port_mmio + PORT_FIS_ADDR_HI);
+
+	hpriv->start_engine(ap);
+
+	if (online)
+		*class = ahci_dev_classify(ap);
+
+	return rc;
+}
+
+static void xgene_ahci_host_stop(struct ata_host *host)
+{
+	struct ahci_host_priv *hpriv = host->private_data;
+
+	ahci_platform_disable_resources(hpriv);
+}
+
+/**
+ * xgene_ahci_pmp_softreset - Issue the softreset to the drives connected
+ *                            to Port Multiplier.
+ * @link: link to reset
+ * @class: Return value to indicate class of device
+ * @deadline: deadline jiffies for the operation
+ *
+ * Due to H/W errata, the controller is unable to save the PMP
+ * field fetched from command header before sending the H2D FIS.
+ * When the device returns the PMP port field in the D2H FIS, there is
+ * a mismatch and results in command completion failure. The workaround
+ * is to write the pmp value to PxFBS.DEV field before issuing any command
+ * to PMP.
+ */
+static int xgene_ahci_pmp_softreset(struct ata_link *link, unsigned int *class,
+			  unsigned long deadline)
+{
+	int pmp = sata_srst_pmp(link);
+	struct ata_port *ap = link->ap;
+	u32 rc;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	u32 port_fbs;
+
+	/*
+	 * Set PxFBS.DEV field with pmp
+	 * value.
+	 */
+	port_fbs = readl(port_mmio + PORT_FBS);
+	port_fbs &= ~PORT_FBS_DEV_MASK;
+	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
+	writel(port_fbs, port_mmio + PORT_FBS);
+
+	rc = ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
+
+	return rc;
+}
+
+/**
+ * xgene_ahci_softreset - Issue the softreset to the drive.
+ * @link: link to reset
+ * @class: Return value to indicate class of device
+ * @deadline: deadline jiffies for the operation
+ *
+ * Due to H/W errata, the controller is unable to save the PMP
+ * field fetched from command header before sending the H2D FIS.
+ * When the device returns the PMP port field in the D2H FIS, there is
+ * a mismatch and results in command completion failure. The workaround
+ * is to write the pmp value to PxFBS.DEV field before issuing any command
+ * to PMP. Here is the algorithm to detect PMP :
+ *
+ * 1. Save the PxFBS value
+ * 2. Program PxFBS.DEV with pmp value send by framework. Framework sends
+ *    0xF for both PMP/NON-PMP initially
+ * 3. Issue softreset
+ * 4. If signature class is PMP goto 6
+ * 5. restore the original PxFBS and goto 3
+ * 6. return
+ */
+static int xgene_ahci_softreset(struct ata_link *link, unsigned int *class,
+			  unsigned long deadline)
+{
+	int pmp = sata_srst_pmp(link);
+	struct ata_port *ap = link->ap;
+	struct ahci_host_priv *hpriv = ap->host->private_data;
+	struct xgene_ahci_context *ctx = hpriv->plat_data;
+	void __iomem *port_mmio = ahci_port_base(ap);
+	u32 port_fbs;
+	u32 port_fbs_save;
+	u32 retry = 1;
+	u32 rc;
+
+	port_fbs_save = readl(port_mmio + PORT_FBS);
+
+	/*
+	 * Set PxFBS.DEV field with pmp
+	 * value.
+	 */
+	port_fbs = readl(port_mmio + PORT_FBS);
+	port_fbs &= ~PORT_FBS_DEV_MASK;
+	port_fbs |= pmp << PORT_FBS_DEV_OFFSET;
+	writel(port_fbs, port_mmio + PORT_FBS);
+
+softreset_retry:
+	rc = ahci_do_softreset(link, class, pmp,
+			       deadline, ahci_check_ready);
+
+	ctx->class[ap->port_no] = *class;
+	if (*class != ATA_DEV_PMP) {
+		/*
+		 * Retry for normal drives without
+		 * setting PxFBS.DEV field with pmp value.
+		 */
+		if (retry--) {
+			writel(port_fbs_save, port_mmio + PORT_FBS);
+			goto softreset_retry;
+		}
+	}
+
+	return rc;
+}
+
+/**
+ * xgene_ahci_handle_broken_edge_irq - Handle the broken irq.
+ * @host: Host that recieved the irq
+ * @irq_masked: HOST_IRQ_STAT value
+ *
+ * For hardware with broken edge trigger latch
+ * the HOST_IRQ_STAT register misses the edge interrupt
+ * when clearing of HOST_IRQ_STAT register and hardware
+ * reporting the PORT_IRQ_STAT register at the
+ * same clock cycle.
+ * As such, the algorithm below outlines the workaround.
+ *
+ * 1. Read HOST_IRQ_STAT register and save the state.
+ * 2. Clear the HOST_IRQ_STAT register.
+ * 3. Read back the HOST_IRQ_STAT register.
+ * 4. If HOST_IRQ_STAT register equals to zero, then
+ *    traverse the rest of port's PORT_IRQ_STAT register
+ *    to check if an interrupt is triggered at that point else
+ *    go to step 6.
+ * 5. If PORT_IRQ_STAT register of rest ports is not equal to zero
+ *    then update the state of HOST_IRQ_STAT saved in step 1.
+ * 6. Handle port interrupts.
+ * 7. Exit
+ */
+static int xgene_ahci_handle_broken_edge_irq(struct ata_host *host,
+					     u32 irq_masked)
+{
+	struct ahci_host_priv *hpriv = host->private_data;
+	void __iomem *port_mmio;
+	int i;
+
+	if (!readl(hpriv->mmio + HOST_IRQ_STAT)) {
+		for (i = 0; i < host->n_ports; i++) {
+			if (irq_masked & (1 << i))
+				continue;
+
+			port_mmio = ahci_port_base(host->ports[i]);
+			if (readl(port_mmio + PORT_IRQ_STAT))
+				irq_masked |= (1 << i);
+		}
+	}
+
+	return ahci_handle_port_intr(host, irq_masked);
+}
+
+static irqreturn_t xgene_ahci_irq_intr(int irq, void *dev_instance)
+{
+	struct ata_host *host = dev_instance;
+	struct ahci_host_priv *hpriv;
+	unsigned int rc = 0;
+	void __iomem *mmio;
+	u32 irq_stat, irq_masked;
+
+	hpriv = host->private_data;
+	mmio = hpriv->mmio;
+
+	/* sigh.  0xffffffff is a valid return from h/w */
+	irq_stat = readl(mmio + HOST_IRQ_STAT);
+	if (!irq_stat)
+		return IRQ_NONE;
+
+	irq_masked = irq_stat & hpriv->port_map;
+
+	spin_lock(&host->lock);
+
+	/*
+	 * HOST_IRQ_STAT behaves as edge triggered latch meaning that
+	 * it should be cleared before all the port events are cleared.
+	 */
+	writel(irq_stat, mmio + HOST_IRQ_STAT);
+
+	rc = xgene_ahci_handle_broken_edge_irq(host, irq_masked);
+
+	spin_unlock(&host->lock);
+
+	return IRQ_RETVAL(rc);
+}
+
+static struct ata_port_operations xgene_ahci_v1_ops = {
+	.inherits = &ahci_ops,
+	.host_stop = xgene_ahci_host_stop,
+	.hardreset = xgene_ahci_hardreset,
+	.read_id = xgene_ahci_read_id,
+	.qc_issue = xgene_ahci_qc_issue,
+	.softreset = xgene_ahci_softreset,
+	.pmp_softreset = xgene_ahci_pmp_softreset
+};
+
+static const struct ata_port_info xgene_ahci_v1_port_info = {
+	.flags = AHCI_FLAG_COMMON | ATA_FLAG_PMP,
+	.pio_mask = ATA_PIO4,
+	.udma_mask = ATA_UDMA6,
+	.port_ops = &xgene_ahci_v1_ops,
+};
+
+static struct ata_port_operations xgene_ahci_v2_ops = {
+	.inherits = &ahci_ops,
+	.host_stop = xgene_ahci_host_stop,
+	.hardreset = xgene_ahci_hardreset,
+	.read_id = xgene_ahci_read_id,
+};
+
+static const struct ata_port_info xgene_ahci_v2_port_info = {
+	.flags = AHCI_FLAG_COMMON | ATA_FLAG_PMP,
+	.pio_mask = ATA_PIO4,
+	.udma_mask = ATA_UDMA6,
+	.port_ops = &xgene_ahci_v2_ops,
+};
+
+static int xgene_ahci_hw_init(struct ahci_host_priv *hpriv)
+{
+	struct xgene_ahci_context *ctx = hpriv->plat_data;
+	int i;
+	int rc;
+	u32 val;
+
+	/* Remove IP RAM out of shutdown */
+	rc = xgene_ahci_init_memram(ctx);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < MAX_AHCI_CHN_PERCTR; i++)
+		xgene_ahci_set_phy_cfg(ctx, i);
+
+	/* AXI disable Mask */
+	writel(0xffffffff, hpriv->mmio + HOST_IRQ_STAT);
+	readl(hpriv->mmio + HOST_IRQ_STAT); /* Force a barrier */
+	writel(0, ctx->csr_core + INTSTATUSMASK);
+	val = readl(ctx->csr_core + INTSTATUSMASK); /* Force a barrier */
+	dev_dbg(ctx->dev, "top level interrupt mask 0x%X value 0x%08X\n",
+		INTSTATUSMASK, val);
+
+	writel(0x0, ctx->csr_core + ERRINTSTATUSMASK);
+	readl(ctx->csr_core + ERRINTSTATUSMASK); /* Force a barrier */
+	writel(0x0, ctx->csr_axi + INT_SLV_TMOMASK);
+	readl(ctx->csr_axi + INT_SLV_TMOMASK);
+
+	/* Enable AXI Interrupt */
+	writel(0xffffffff, ctx->csr_core + SLVRDERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_core + SLVWRERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_core + MSTRDERRATTRIBUTES);
+	writel(0xffffffff, ctx->csr_core + MSTWRERRATTRIBUTES);
+
+	/* Enable coherency */
+	val = readl(ctx->csr_core + BUSCTLREG);
+	val &= ~0x00000002;     /* Enable write coherency */
+	val &= ~0x00000001;     /* Enable read coherency */
+	writel(val, ctx->csr_core + BUSCTLREG);
+
+	val = readl(ctx->csr_core + IOFMSTRWAUX);
+	val |= (1 << 3);        /* Enable read coherency */
+	val |= (1 << 9);        /* Enable write coherency */
+	writel(val, ctx->csr_core + IOFMSTRWAUX);
+	val = readl(ctx->csr_core + IOFMSTRWAUX);
+	dev_dbg(ctx->dev, "coherency 0x%X value 0x%08X\n",
+		IOFMSTRWAUX, val);
+
+	return rc;
+}
+
+static int xgene_ahci_mux_select(struct xgene_ahci_context *ctx)
+{
+	u32 val;
+
+	/* Check for optional MUX resource */
+	if (!ctx->csr_mux)
+		return 0;
+
+	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
+	val &= ~CFG_SATA_ENET_SELECT_MASK;
+	writel(val, ctx->csr_mux + SATA_ENET_CONFIG_REG);
+	val = readl(ctx->csr_mux + SATA_ENET_CONFIG_REG);
+	return val & CFG_SATA_ENET_SELECT_MASK ? -1 : 0;
+}
+
+static struct scsi_host_template ahci_platform_sht = {
+	AHCI_SHT(DRV_NAME),
+};
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_ahci_acpi_match[] = {
+	{ "APMC0D0D", XGENE_AHCI_V1},
+	{ "APMC0D32", XGENE_AHCI_V2},
+	{},
+};
+MODULE_DEVICE_TABLE(acpi, xgene_ahci_acpi_match);
+#endif
+
+static const struct of_device_id xgene_ahci_of_match[] = {
+	{.compatible = "apm,xgene-ahci", .data = (void *) XGENE_AHCI_V1},
+	{.compatible = "apm,xgene-ahci-v2", .data = (void *) XGENE_AHCI_V2},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, xgene_ahci_of_match);
+
+static int xgene_ahci_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ahci_host_priv *hpriv;
+	struct xgene_ahci_context *ctx;
+	struct resource *res;
+	const struct of_device_id *of_devid;
+	enum xgene_ahci_version version = XGENE_AHCI_V1;
+	const struct ata_port_info *ppi[] = { &xgene_ahci_v1_port_info,
+					      &xgene_ahci_v2_port_info };
+	int rc;
+
+	hpriv = ahci_platform_get_resources(pdev, 0);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+
+	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	hpriv->plat_data = ctx;
+	ctx->hpriv = hpriv;
+	ctx->dev = dev;
+
+	/* Retrieve the IP core resource */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	ctx->csr_core = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ctx->csr_core))
+		return PTR_ERR(ctx->csr_core);
+
+	/* Retrieve the IP diagnostic resource */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	ctx->csr_diag = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ctx->csr_diag))
+		return PTR_ERR(ctx->csr_diag);
+
+	/* Retrieve the IP AXI resource */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	ctx->csr_axi = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ctx->csr_axi))
+		return PTR_ERR(ctx->csr_axi);
+
+	/* Retrieve the optional IP mux resource */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 4);
+	if (res) {
+		void __iomem *csr = devm_ioremap_resource(dev, res);
+		if (IS_ERR(csr))
+			return PTR_ERR(csr);
+
+		ctx->csr_mux = csr;
+	}
+
+	of_devid = of_match_device(xgene_ahci_of_match, dev);
+	if (of_devid) {
+		if (of_devid->data)
+			version = (unsigned long) of_devid->data;
+	}
+#ifdef CONFIG_ACPI
+	else {
+		const struct acpi_device_id *acpi_id;
+		struct acpi_device_info *info;
+		acpi_status status;
+
+		acpi_id = acpi_match_device(xgene_ahci_acpi_match, &pdev->dev);
+		if (!acpi_id) {
+			dev_warn(&pdev->dev, "No node entry in ACPI table. Assume version1\n");
+			version = XGENE_AHCI_V1;
+		} else if (acpi_id->driver_data) {
+			version = (enum xgene_ahci_version) acpi_id->driver_data;
+			status = acpi_get_object_info(ACPI_HANDLE(&pdev->dev), &info);
+			if (ACPI_FAILURE(status)) {
+				dev_warn(&pdev->dev, "%s: Error reading device info. Assume version1\n",
+					__func__);
+				version = XGENE_AHCI_V1;
+			} else {
+				if (info->valid & ACPI_VALID_CID)
+					version = XGENE_AHCI_V2;
+				kfree(info);
+			}
+		}
+	}
+#endif
+
+	dev_dbg(dev, "VAddr 0x%p Mmio VAddr 0x%p\n", ctx->csr_core,
+		hpriv->mmio);
+
+	/* Select ATA */
+	if ((rc = xgene_ahci_mux_select(ctx))) {
+		dev_err(dev, "SATA mux selection failed error %d\n", rc);
+		return -ENODEV;
+	}
+
+	if (xgene_ahci_is_memram_inited(ctx)) {
+		dev_info(dev, "skip clock and PHY initialization\n");
+		goto skip_clk_phy;
+	}
+
+	/* Due to errata, HW requires full toggle transition */
+	rc = ahci_platform_enable_clks(hpriv);
+	if (rc)
+		goto disable_resources;
+	ahci_platform_disable_clks(hpriv);
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		goto disable_resources;
+
+	/* Configure the host controller */
+	xgene_ahci_hw_init(hpriv);
+skip_clk_phy:
+
+	switch (version) {
+	case XGENE_AHCI_V1:
+		hpriv->flags = AHCI_HFLAG_NO_NCQ;
+		break;
+	case XGENE_AHCI_V2:
+		hpriv->flags |= AHCI_HFLAG_YES_FBS;
+		hpriv->irq_handler = xgene_ahci_irq_intr;
+		break;
+	default:
+		break;
+	}
+
+	rc = ahci_platform_init_host(pdev, hpriv, ppi[version - 1],
+				     &ahci_platform_sht);
+	if (rc)
+		goto disable_resources;
+
+	dev_dbg(dev, "X-Gene SATA host controller initialized\n");
+	return 0;
+
+disable_resources:
+	ahci_platform_disable_resources(hpriv);
+	return rc;
+}
+
+static struct platform_driver xgene_ahci_driver = {
+	.probe = xgene_ahci_probe,
+	.remove = ata_platform_remove_one,
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = xgene_ahci_of_match,
+		.acpi_match_table = ACPI_PTR(xgene_ahci_acpi_match),
+	},
+};
+
+module_platform_driver(xgene_ahci_driver);
+
+MODULE_DESCRIPTION("APM X-Gene AHCI SATA driver");
+MODULE_AUTHOR("Loc Ho <lho@apm.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("0.4");