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, 675 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_atpx_handler.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_atpx_handler.c
new file mode 100644
index 000000000..d6d986be9
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_atpx_handler.c
@@ -0,0 +1,675 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2010 Red Hat Inc.
+ * Author : Dave Airlie <airlied@redhat.com>
+ *
+ * ATPX support for both Intel/ATI
+ */
+#include <linux/vga_switcheroo.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+
+#include "amdgpu.h"
+#include "amd_acpi.h"
+
+#define AMDGPU_PX_QUIRK_FORCE_ATPX  (1 << 0)
+
+struct amdgpu_px_quirk {
+	u32 chip_vendor;
+	u32 chip_device;
+	u32 subsys_vendor;
+	u32 subsys_device;
+	u32 px_quirk_flags;
+};
+
+struct amdgpu_atpx_functions {
+	bool px_params;
+	bool power_cntl;
+	bool disp_mux_cntl;
+	bool i2c_mux_cntl;
+	bool switch_start;
+	bool switch_end;
+	bool disp_connectors_mapping;
+	bool disp_detection_ports;
+};
+
+struct amdgpu_atpx {
+	acpi_handle handle;
+	struct amdgpu_atpx_functions functions;
+	bool is_hybrid;
+	bool dgpu_req_power_for_displays;
+};
+
+static struct amdgpu_atpx_priv {
+	bool atpx_detected;
+	bool bridge_pm_usable;
+	unsigned int quirks;
+	/* handle for device - and atpx */
+	acpi_handle dhandle;
+	acpi_handle other_handle;
+	struct amdgpu_atpx atpx;
+} amdgpu_atpx_priv;
+
+struct atpx_verify_interface {
+	u16 size;		/* structure size in bytes (includes size field) */
+	u16 version;		/* version */
+	u32 function_bits;	/* supported functions bit vector */
+} __packed;
+
+struct atpx_px_params {
+	u16 size;		/* structure size in bytes (includes size field) */
+	u32 valid_flags;	/* which flags are valid */
+	u32 flags;		/* flags */
+} __packed;
+
+struct atpx_power_control {
+	u16 size;
+	u8 dgpu_state;
+} __packed;
+
+struct atpx_mux {
+	u16 size;
+	u16 mux;
+} __packed;
+
+bool amdgpu_has_atpx(void) {
+	return amdgpu_atpx_priv.atpx_detected;
+}
+
+bool amdgpu_has_atpx_dgpu_power_cntl(void) {
+	return amdgpu_atpx_priv.atpx.functions.power_cntl;
+}
+
+bool amdgpu_is_atpx_hybrid(void) {
+	return amdgpu_atpx_priv.atpx.is_hybrid;
+}
+
+bool amdgpu_atpx_dgpu_req_power_for_displays(void) {
+	return amdgpu_atpx_priv.atpx.dgpu_req_power_for_displays;
+}
+
+#if defined(CONFIG_ACPI)
+void *amdgpu_atpx_get_dhandle(void) {
+	return amdgpu_atpx_priv.dhandle;
+}
+#endif
+
+/**
+ * amdgpu_atpx_call - call an ATPX method
+ *
+ * @handle: acpi handle
+ * @function: the ATPX function to execute
+ * @params: ATPX function params
+ *
+ * Executes the requested ATPX function (all asics).
+ * Returns a pointer to the acpi output buffer.
+ */
+static union acpi_object *amdgpu_atpx_call(acpi_handle handle, int function,
+					   struct acpi_buffer *params)
+{
+	acpi_status status;
+	union acpi_object atpx_arg_elements[2];
+	struct acpi_object_list atpx_arg;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	atpx_arg.count = 2;
+	atpx_arg.pointer = &atpx_arg_elements[0];
+
+	atpx_arg_elements[0].type = ACPI_TYPE_INTEGER;
+	atpx_arg_elements[0].integer.value = function;
+
+	if (params) {
+		atpx_arg_elements[1].type = ACPI_TYPE_BUFFER;
+		atpx_arg_elements[1].buffer.length = params->length;
+		atpx_arg_elements[1].buffer.pointer = params->pointer;
+	} else {
+		/* We need a second fake parameter */
+		atpx_arg_elements[1].type = ACPI_TYPE_INTEGER;
+		atpx_arg_elements[1].integer.value = 0;
+	}
+
+	status = acpi_evaluate_object(handle, NULL, &atpx_arg, &buffer);
+
+	/* Fail only if calling the method fails and ATPX is supported */
+	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
+		printk("failed to evaluate ATPX got %s\n",
+		       acpi_format_exception(status));
+		kfree(buffer.pointer);
+		return NULL;
+	}
+
+	return buffer.pointer;
+}
+
+/**
+ * amdgpu_atpx_parse_functions - parse supported functions
+ *
+ * @f: supported functions struct
+ * @mask: supported functions mask from ATPX
+ *
+ * Use the supported functions mask from ATPX function
+ * ATPX_FUNCTION_VERIFY_INTERFACE to determine what functions
+ * are supported (all asics).
+ */
+static void amdgpu_atpx_parse_functions(struct amdgpu_atpx_functions *f, u32 mask)
+{
+	f->px_params = mask & ATPX_GET_PX_PARAMETERS_SUPPORTED;
+	f->power_cntl = mask & ATPX_POWER_CONTROL_SUPPORTED;
+	f->disp_mux_cntl = mask & ATPX_DISPLAY_MUX_CONTROL_SUPPORTED;
+	f->i2c_mux_cntl = mask & ATPX_I2C_MUX_CONTROL_SUPPORTED;
+	f->switch_start = mask & ATPX_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION_SUPPORTED;
+	f->switch_end = mask & ATPX_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION_SUPPORTED;
+	f->disp_connectors_mapping = mask & ATPX_GET_DISPLAY_CONNECTORS_MAPPING_SUPPORTED;
+	f->disp_detection_ports = mask & ATPX_GET_DISPLAY_DETECTION_PORTS_SUPPORTED;
+}
+
+/**
+ * amdgpu_atpx_validate - validate ATPX functions
+ *
+ * @atpx: amdgpu atpx struct
+ *
+ * Validate that required functions are enabled (all asics).
+ * returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_validate(struct amdgpu_atpx *atpx)
+{
+	u32 valid_bits = 0;
+
+	if (atpx->functions.px_params) {
+		union acpi_object *info;
+		struct atpx_px_params output;
+		size_t size;
+
+		info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_GET_PX_PARAMETERS, NULL);
+		if (!info)
+			return -EIO;
+
+		memset(&output, 0, sizeof(output));
+
+		size = *(u16 *) info->buffer.pointer;
+		if (size < 10) {
+			printk("ATPX buffer is too small: %zu\n", size);
+			kfree(info);
+			return -EINVAL;
+		}
+		size = min(sizeof(output), size);
+
+		memcpy(&output, info->buffer.pointer, size);
+
+		valid_bits = output.flags & output.valid_flags;
+
+		kfree(info);
+	}
+
+	/* if separate mux flag is set, mux controls are required */
+	if (valid_bits & ATPX_SEPARATE_MUX_FOR_I2C) {
+		atpx->functions.i2c_mux_cntl = true;
+		atpx->functions.disp_mux_cntl = true;
+	}
+	/* if any outputs are muxed, mux controls are required */
+	if (valid_bits & (ATPX_CRT1_RGB_SIGNAL_MUXED |
+			  ATPX_TV_SIGNAL_MUXED |
+			  ATPX_DFP_SIGNAL_MUXED))
+		atpx->functions.disp_mux_cntl = true;
+
+
+	/* some bioses set these bits rather than flagging power_cntl as supported */
+	if (valid_bits & (ATPX_DYNAMIC_PX_SUPPORTED |
+			  ATPX_DYNAMIC_DGPU_POWER_OFF_SUPPORTED))
+		atpx->functions.power_cntl = true;
+
+	atpx->is_hybrid = false;
+	if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
+		if (amdgpu_atpx_priv.quirks & AMDGPU_PX_QUIRK_FORCE_ATPX) {
+			printk("ATPX Hybrid Graphics, forcing to ATPX\n");
+			atpx->functions.power_cntl = true;
+			atpx->is_hybrid = false;
+		} else {
+			printk("ATPX Hybrid Graphics\n");
+			/*
+			 * Disable legacy PM methods only when pcie port PM is usable,
+			 * otherwise the device might fail to power off or power on.
+			 */
+			atpx->functions.power_cntl = !amdgpu_atpx_priv.bridge_pm_usable;
+			atpx->is_hybrid = true;
+		}
+	}
+
+	atpx->dgpu_req_power_for_displays = false;
+	if (valid_bits & ATPX_DGPU_REQ_POWER_FOR_DISPLAYS)
+		atpx->dgpu_req_power_for_displays = true;
+
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_verify_interface - verify ATPX
+ *
+ * @atpx: amdgpu atpx struct
+ *
+ * Execute the ATPX_FUNCTION_VERIFY_INTERFACE ATPX function
+ * to initialize ATPX and determine what features are supported
+ * (all asics).
+ * returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_verify_interface(struct amdgpu_atpx *atpx)
+{
+	union acpi_object *info;
+	struct atpx_verify_interface output;
+	size_t size;
+	int err = 0;
+
+	info = amdgpu_atpx_call(atpx->handle, ATPX_FUNCTION_VERIFY_INTERFACE, NULL);
+	if (!info)
+		return -EIO;
+
+	memset(&output, 0, sizeof(output));
+
+	size = *(u16 *) info->buffer.pointer;
+	if (size < 8) {
+		printk("ATPX buffer is too small: %zu\n", size);
+		err = -EINVAL;
+		goto out;
+	}
+	size = min(sizeof(output), size);
+
+	memcpy(&output, info->buffer.pointer, size);
+
+	/* TODO: check version? */
+	printk("ATPX version %u, functions 0x%08x\n",
+	       output.version, output.function_bits);
+
+	amdgpu_atpx_parse_functions(&atpx->functions, output.function_bits);
+
+out:
+	kfree(info);
+	return err;
+}
+
+/**
+ * amdgpu_atpx_set_discrete_state - power up/down discrete GPU
+ *
+ * @atpx: atpx info struct
+ * @state: discrete GPU state (0 = power down, 1 = power up)
+ *
+ * Execute the ATPX_FUNCTION_POWER_CONTROL ATPX function to
+ * power down/up the discrete GPU (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_set_discrete_state(struct amdgpu_atpx *atpx, u8 state)
+{
+	struct acpi_buffer params;
+	union acpi_object *info;
+	struct atpx_power_control input;
+
+	if (atpx->functions.power_cntl) {
+		input.size = 3;
+		input.dgpu_state = state;
+		params.length = input.size;
+		params.pointer = &input;
+		info = amdgpu_atpx_call(atpx->handle,
+					ATPX_FUNCTION_POWER_CONTROL,
+					&params);
+		if (!info)
+			return -EIO;
+		kfree(info);
+
+		/* 200ms delay is required after off */
+		if (state == 0)
+			msleep(200);
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_switch_disp_mux - switch display mux
+ *
+ * @atpx: atpx info struct
+ * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
+ *
+ * Execute the ATPX_FUNCTION_DISPLAY_MUX_CONTROL ATPX function to
+ * switch the display mux between the discrete GPU and integrated GPU
+ * (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_switch_disp_mux(struct amdgpu_atpx *atpx, u16 mux_id)
+{
+	struct acpi_buffer params;
+	union acpi_object *info;
+	struct atpx_mux input;
+
+	if (atpx->functions.disp_mux_cntl) {
+		input.size = 4;
+		input.mux = mux_id;
+		params.length = input.size;
+		params.pointer = &input;
+		info = amdgpu_atpx_call(atpx->handle,
+					ATPX_FUNCTION_DISPLAY_MUX_CONTROL,
+					&params);
+		if (!info)
+			return -EIO;
+		kfree(info);
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_switch_i2c_mux - switch i2c/hpd mux
+ *
+ * @atpx: atpx info struct
+ * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
+ *
+ * Execute the ATPX_FUNCTION_I2C_MUX_CONTROL ATPX function to
+ * switch the i2c/hpd mux between the discrete GPU and integrated GPU
+ * (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_switch_i2c_mux(struct amdgpu_atpx *atpx, u16 mux_id)
+{
+	struct acpi_buffer params;
+	union acpi_object *info;
+	struct atpx_mux input;
+
+	if (atpx->functions.i2c_mux_cntl) {
+		input.size = 4;
+		input.mux = mux_id;
+		params.length = input.size;
+		params.pointer = &input;
+		info = amdgpu_atpx_call(atpx->handle,
+					ATPX_FUNCTION_I2C_MUX_CONTROL,
+					&params);
+		if (!info)
+			return -EIO;
+		kfree(info);
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_switch_start - notify the sbios of a GPU switch
+ *
+ * @atpx: atpx info struct
+ * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
+ *
+ * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION ATPX
+ * function to notify the sbios that a switch between the discrete GPU and
+ * integrated GPU has begun (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_switch_start(struct amdgpu_atpx *atpx, u16 mux_id)
+{
+	struct acpi_buffer params;
+	union acpi_object *info;
+	struct atpx_mux input;
+
+	if (atpx->functions.switch_start) {
+		input.size = 4;
+		input.mux = mux_id;
+		params.length = input.size;
+		params.pointer = &input;
+		info = amdgpu_atpx_call(atpx->handle,
+					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_START_NOTIFICATION,
+					&params);
+		if (!info)
+			return -EIO;
+		kfree(info);
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_switch_end - notify the sbios of a GPU switch
+ *
+ * @atpx: atpx info struct
+ * @mux_id: mux state (0 = integrated GPU, 1 = discrete GPU)
+ *
+ * Execute the ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION ATPX
+ * function to notify the sbios that a switch between the discrete GPU and
+ * integrated GPU has ended (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_switch_end(struct amdgpu_atpx *atpx, u16 mux_id)
+{
+	struct acpi_buffer params;
+	union acpi_object *info;
+	struct atpx_mux input;
+
+	if (atpx->functions.switch_end) {
+		input.size = 4;
+		input.mux = mux_id;
+		params.length = input.size;
+		params.pointer = &input;
+		info = amdgpu_atpx_call(atpx->handle,
+					ATPX_FUNCTION_GRAPHICS_DEVICE_SWITCH_END_NOTIFICATION,
+					&params);
+		if (!info)
+			return -EIO;
+		kfree(info);
+	}
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_switchto - switch to the requested GPU
+ *
+ * @id: GPU to switch to
+ *
+ * Execute the necessary ATPX functions to switch between the discrete GPU and
+ * integrated GPU (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_switchto(enum vga_switcheroo_client_id id)
+{
+	u16 gpu_id;
+
+	if (id == VGA_SWITCHEROO_IGD)
+		gpu_id = ATPX_INTEGRATED_GPU;
+	else
+		gpu_id = ATPX_DISCRETE_GPU;
+
+	amdgpu_atpx_switch_start(&amdgpu_atpx_priv.atpx, gpu_id);
+	amdgpu_atpx_switch_disp_mux(&amdgpu_atpx_priv.atpx, gpu_id);
+	amdgpu_atpx_switch_i2c_mux(&amdgpu_atpx_priv.atpx, gpu_id);
+	amdgpu_atpx_switch_end(&amdgpu_atpx_priv.atpx, gpu_id);
+
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_power_state - power down/up the requested GPU
+ *
+ * @id: GPU to power down/up
+ * @state: requested power state (0 = off, 1 = on)
+ *
+ * Execute the necessary ATPX function to power down/up the discrete GPU
+ * (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_power_state(enum vga_switcheroo_client_id id,
+				   enum vga_switcheroo_state state)
+{
+	/* on w500 ACPI can't change intel gpu state */
+	if (id == VGA_SWITCHEROO_IGD)
+		return 0;
+
+	amdgpu_atpx_set_discrete_state(&amdgpu_atpx_priv.atpx, state);
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_pci_probe_handle - look up the ATPX handle
+ *
+ * @pdev: pci device
+ *
+ * Look up the ATPX handles (all asics).
+ * Returns true if the handles are found, false if not.
+ */
+static bool amdgpu_atpx_pci_probe_handle(struct pci_dev *pdev)
+{
+	acpi_handle dhandle, atpx_handle;
+	acpi_status status;
+
+	dhandle = ACPI_HANDLE(&pdev->dev);
+	if (!dhandle)
+		return false;
+
+	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
+	if (ACPI_FAILURE(status)) {
+		amdgpu_atpx_priv.other_handle = dhandle;
+		return false;
+	}
+	amdgpu_atpx_priv.dhandle = dhandle;
+	amdgpu_atpx_priv.atpx.handle = atpx_handle;
+	return true;
+}
+
+/**
+ * amdgpu_atpx_init - verify the ATPX interface
+ *
+ * Verify the ATPX interface (all asics).
+ * Returns 0 on success, error on failure.
+ */
+static int amdgpu_atpx_init(void)
+{
+	int r;
+
+	/* set up the ATPX handle */
+	r = amdgpu_atpx_verify_interface(&amdgpu_atpx_priv.atpx);
+	if (r)
+		return r;
+
+	/* validate the atpx setup */
+	r = amdgpu_atpx_validate(&amdgpu_atpx_priv.atpx);
+	if (r)
+		return r;
+
+	return 0;
+}
+
+/**
+ * amdgpu_atpx_get_client_id - get the client id
+ *
+ * @pdev: pci device
+ *
+ * look up whether we are the integrated or discrete GPU (all asics).
+ * Returns the client id.
+ */
+static enum vga_switcheroo_client_id amdgpu_atpx_get_client_id(struct pci_dev *pdev)
+{
+	if (amdgpu_atpx_priv.dhandle == ACPI_HANDLE(&pdev->dev))
+		return VGA_SWITCHEROO_IGD;
+	else
+		return VGA_SWITCHEROO_DIS;
+}
+
+static const struct vga_switcheroo_handler amdgpu_atpx_handler = {
+	.switchto = amdgpu_atpx_switchto,
+	.power_state = amdgpu_atpx_power_state,
+	.get_client_id = amdgpu_atpx_get_client_id,
+};
+
+static const struct amdgpu_px_quirk amdgpu_px_quirk_list[] = {
+	/* HG _PR3 doesn't seem to work on this A+A weston board */
+	{ 0x1002, 0x6900, 0x1002, 0x0124, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0x1002, 0x6900, 0x1028, 0x0812, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0x1002, 0x6900, 0x1028, 0x0813, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0x1002, 0x699f, 0x1028, 0x0814, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0x1002, 0x6900, 0x1025, 0x125A, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0x1002, 0x6900, 0x17AA, 0x3806, AMDGPU_PX_QUIRK_FORCE_ATPX },
+	{ 0, 0, 0, 0, 0 },
+};
+
+static void amdgpu_atpx_get_quirks(struct pci_dev *pdev)
+{
+	const struct amdgpu_px_quirk *p = amdgpu_px_quirk_list;
+
+	/* Apply PX quirks */
+	while (p && p->chip_device != 0) {
+		if (pdev->vendor == p->chip_vendor &&
+		    pdev->device == p->chip_device &&
+		    pdev->subsystem_vendor == p->subsys_vendor &&
+		    pdev->subsystem_device == p->subsys_device) {
+			amdgpu_atpx_priv.quirks |= p->px_quirk_flags;
+			break;
+		}
+		++p;
+	}
+}
+
+/**
+ * amdgpu_atpx_detect - detect whether we have PX
+ *
+ * Check if we have a PX system (all asics).
+ * Returns true if we have a PX system, false if not.
+ */
+static bool amdgpu_atpx_detect(void)
+{
+	char acpi_method_name[255] = { 0 };
+	struct acpi_buffer buffer = {sizeof(acpi_method_name), acpi_method_name};
+	struct pci_dev *pdev = NULL;
+	bool has_atpx = false;
+	int vga_count = 0;
+	bool d3_supported = false;
+	struct pci_dev *parent_pdev;
+
+	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev)) != NULL) {
+		vga_count++;
+
+		has_atpx |= amdgpu_atpx_pci_probe_handle(pdev);
+
+		parent_pdev = pci_upstream_bridge(pdev);
+		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
+		amdgpu_atpx_get_quirks(pdev);
+	}
+
+	while ((pdev = pci_get_class(PCI_CLASS_DISPLAY_OTHER << 8, pdev)) != NULL) {
+		vga_count++;
+
+		has_atpx |= amdgpu_atpx_pci_probe_handle(pdev);
+
+		parent_pdev = pci_upstream_bridge(pdev);
+		d3_supported |= parent_pdev && parent_pdev->bridge_d3;
+		amdgpu_atpx_get_quirks(pdev);
+	}
+
+	if (has_atpx && vga_count == 2) {
+		acpi_get_name(amdgpu_atpx_priv.atpx.handle, ACPI_FULL_PATHNAME, &buffer);
+		pr_info("vga_switcheroo: detected switching method %s handle\n",
+			acpi_method_name);
+		amdgpu_atpx_priv.atpx_detected = true;
+		amdgpu_atpx_priv.bridge_pm_usable = d3_supported;
+		amdgpu_atpx_init();
+		return true;
+	}
+	return false;
+}
+
+/**
+ * amdgpu_register_atpx_handler - register with vga_switcheroo
+ *
+ * Register the PX callbacks with vga_switcheroo (all asics).
+ */
+void amdgpu_register_atpx_handler(void)
+{
+	bool r;
+	enum vga_switcheroo_handler_flags_t handler_flags = 0;
+
+	/* detect if we have any ATPX + 2 VGA in the system */
+	r = amdgpu_atpx_detect();
+	if (!r)
+		return;
+
+	vga_switcheroo_register_handler(&amdgpu_atpx_handler, handler_flags);
+}
+
+/**
+ * amdgpu_unregister_atpx_handler - unregister with vga_switcheroo
+ *
+ * Unregister the PX callbacks with vga_switcheroo (all asics).
+ */
+void amdgpu_unregister_atpx_handler(void)
+{
+	vga_switcheroo_unregister_handler();
+}