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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/pci/ats.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'drivers/pci/ats.c')
-rw-r--r--drivers/pci/ats.c511
1 files changed, 511 insertions, 0 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
new file mode 100644
index 000000000..f9cc2e10b
--- /dev/null
+++ b/drivers/pci/ats.c
@@ -0,0 +1,511 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI Express I/O Virtualization (IOV) support
+ * Address Translation Service 1.0
+ * Page Request Interface added by Joerg Roedel <joerg.roedel@amd.com>
+ * PASID support added by Joerg Roedel <joerg.roedel@amd.com>
+ *
+ * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com>
+ * Copyright (C) 2011 Advanced Micro Devices,
+ */
+
+#include <linux/export.h>
+#include <linux/pci-ats.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+
+#include "pci.h"
+
+void pci_ats_init(struct pci_dev *dev)
+{
+ int pos;
+
+ if (pci_ats_disabled())
+ return;
+
+ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS);
+ if (!pos)
+ return;
+
+ dev->ats_cap = pos;
+}
+
+/**
+ * pci_ats_supported - check if the device can use ATS
+ * @dev: the PCI device
+ *
+ * Returns true if the device supports ATS and is allowed to use it, false
+ * otherwise.
+ */
+bool pci_ats_supported(struct pci_dev *dev)
+{
+ if (!dev->ats_cap)
+ return false;
+
+ return (dev->untrusted == 0);
+}
+EXPORT_SYMBOL_GPL(pci_ats_supported);
+
+/**
+ * pci_enable_ats - enable the ATS capability
+ * @dev: the PCI device
+ * @ps: the IOMMU page shift
+ *
+ * Returns 0 on success, or negative on failure.
+ */
+int pci_enable_ats(struct pci_dev *dev, int ps)
+{
+ u16 ctrl;
+ struct pci_dev *pdev;
+
+ if (!pci_ats_supported(dev))
+ return -EINVAL;
+
+ if (WARN_ON(dev->ats_enabled))
+ return -EBUSY;
+
+ if (ps < PCI_ATS_MIN_STU)
+ return -EINVAL;
+
+ /*
+ * Note that enabling ATS on a VF fails unless it's already enabled
+ * with the same STU on the PF.
+ */
+ ctrl = PCI_ATS_CTRL_ENABLE;
+ if (dev->is_virtfn) {
+ pdev = pci_physfn(dev);
+ if (pdev->ats_stu != ps)
+ return -EINVAL;
+ } else {
+ dev->ats_stu = ps;
+ ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
+ }
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
+
+ dev->ats_enabled = 1;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pci_enable_ats);
+
+/**
+ * pci_disable_ats - disable the ATS capability
+ * @dev: the PCI device
+ */
+void pci_disable_ats(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ if (WARN_ON(!dev->ats_enabled))
+ return;
+
+ pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, &ctrl);
+ ctrl &= ~PCI_ATS_CTRL_ENABLE;
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
+
+ dev->ats_enabled = 0;
+}
+EXPORT_SYMBOL_GPL(pci_disable_ats);
+
+void pci_restore_ats_state(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ if (!dev->ats_enabled)
+ return;
+
+ ctrl = PCI_ATS_CTRL_ENABLE;
+ if (!dev->is_virtfn)
+ ctrl |= PCI_ATS_CTRL_STU(dev->ats_stu - PCI_ATS_MIN_STU);
+ pci_write_config_word(dev, dev->ats_cap + PCI_ATS_CTRL, ctrl);
+}
+
+/**
+ * pci_ats_queue_depth - query the ATS Invalidate Queue Depth
+ * @dev: the PCI device
+ *
+ * Returns the queue depth on success, or negative on failure.
+ *
+ * The ATS spec uses 0 in the Invalidate Queue Depth field to
+ * indicate that the function can accept 32 Invalidate Request.
+ * But here we use the `real' values (i.e. 1~32) for the Queue
+ * Depth; and 0 indicates the function shares the Queue with
+ * other functions (doesn't exclusively own a Queue).
+ */
+int pci_ats_queue_depth(struct pci_dev *dev)
+{
+ u16 cap;
+
+ if (!dev->ats_cap)
+ return -EINVAL;
+
+ if (dev->is_virtfn)
+ return 0;
+
+ pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap);
+ return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : PCI_ATS_MAX_QDEP;
+}
+
+/**
+ * pci_ats_page_aligned - Return Page Aligned Request bit status.
+ * @pdev: the PCI device
+ *
+ * Returns 1, if the Untranslated Addresses generated by the device
+ * are always aligned or 0 otherwise.
+ *
+ * Per PCIe spec r4.0, sec 10.5.1.2, if the Page Aligned Request bit
+ * is set, it indicates the Untranslated Addresses generated by the
+ * device are always aligned to a 4096 byte boundary.
+ */
+int pci_ats_page_aligned(struct pci_dev *pdev)
+{
+ u16 cap;
+
+ if (!pdev->ats_cap)
+ return 0;
+
+ pci_read_config_word(pdev, pdev->ats_cap + PCI_ATS_CAP, &cap);
+
+ if (cap & PCI_ATS_CAP_PAGE_ALIGNED)
+ return 1;
+
+ return 0;
+}
+
+#ifdef CONFIG_PCI_PRI
+void pci_pri_init(struct pci_dev *pdev)
+{
+ u16 status;
+
+ pdev->pri_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
+
+ if (!pdev->pri_cap)
+ return;
+
+ pci_read_config_word(pdev, pdev->pri_cap + PCI_PRI_STATUS, &status);
+ if (status & PCI_PRI_STATUS_PASID)
+ pdev->pasid_required = 1;
+}
+
+/**
+ * pci_enable_pri - Enable PRI capability
+ * @pdev: PCI device structure
+ * @reqs: outstanding requests
+ *
+ * Returns 0 on success, negative value on error
+ */
+int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
+{
+ u16 control, status;
+ u32 max_requests;
+ int pri = pdev->pri_cap;
+
+ /*
+ * VFs must not implement the PRI Capability. If their PF
+ * implements PRI, it is shared by the VFs, so if the PF PRI is
+ * enabled, it is also enabled for the VF.
+ */
+ if (pdev->is_virtfn) {
+ if (pci_physfn(pdev)->pri_enabled)
+ return 0;
+ return -EINVAL;
+ }
+
+ if (WARN_ON(pdev->pri_enabled))
+ return -EBUSY;
+
+ if (!pri)
+ return -EINVAL;
+
+ pci_read_config_word(pdev, pri + PCI_PRI_STATUS, &status);
+ if (!(status & PCI_PRI_STATUS_STOPPED))
+ return -EBUSY;
+
+ pci_read_config_dword(pdev, pri + PCI_PRI_MAX_REQ, &max_requests);
+ reqs = min(max_requests, reqs);
+ pdev->pri_reqs_alloc = reqs;
+ pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
+
+ control = PCI_PRI_CTRL_ENABLE;
+ pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
+
+ pdev->pri_enabled = 1;
+
+ return 0;
+}
+
+/**
+ * pci_disable_pri - Disable PRI capability
+ * @pdev: PCI device structure
+ *
+ * Only clears the enabled-bit, regardless of its former value
+ */
+void pci_disable_pri(struct pci_dev *pdev)
+{
+ u16 control;
+ int pri = pdev->pri_cap;
+
+ /* VFs share the PF PRI */
+ if (pdev->is_virtfn)
+ return;
+
+ if (WARN_ON(!pdev->pri_enabled))
+ return;
+
+ if (!pri)
+ return;
+
+ pci_read_config_word(pdev, pri + PCI_PRI_CTRL, &control);
+ control &= ~PCI_PRI_CTRL_ENABLE;
+ pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
+
+ pdev->pri_enabled = 0;
+}
+EXPORT_SYMBOL_GPL(pci_disable_pri);
+
+/**
+ * pci_restore_pri_state - Restore PRI
+ * @pdev: PCI device structure
+ */
+void pci_restore_pri_state(struct pci_dev *pdev)
+{
+ u16 control = PCI_PRI_CTRL_ENABLE;
+ u32 reqs = pdev->pri_reqs_alloc;
+ int pri = pdev->pri_cap;
+
+ if (pdev->is_virtfn)
+ return;
+
+ if (!pdev->pri_enabled)
+ return;
+
+ if (!pri)
+ return;
+
+ pci_write_config_dword(pdev, pri + PCI_PRI_ALLOC_REQ, reqs);
+ pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
+}
+
+/**
+ * pci_reset_pri - Resets device's PRI state
+ * @pdev: PCI device structure
+ *
+ * The PRI capability must be disabled before this function is called.
+ * Returns 0 on success, negative value on error.
+ */
+int pci_reset_pri(struct pci_dev *pdev)
+{
+ u16 control;
+ int pri = pdev->pri_cap;
+
+ if (pdev->is_virtfn)
+ return 0;
+
+ if (WARN_ON(pdev->pri_enabled))
+ return -EBUSY;
+
+ if (!pri)
+ return -EINVAL;
+
+ control = PCI_PRI_CTRL_RESET;
+ pci_write_config_word(pdev, pri + PCI_PRI_CTRL, control);
+
+ return 0;
+}
+
+/**
+ * pci_prg_resp_pasid_required - Return PRG Response PASID Required bit
+ * status.
+ * @pdev: PCI device structure
+ *
+ * Returns 1 if PASID is required in PRG Response Message, 0 otherwise.
+ */
+int pci_prg_resp_pasid_required(struct pci_dev *pdev)
+{
+ if (pdev->is_virtfn)
+ pdev = pci_physfn(pdev);
+
+ return pdev->pasid_required;
+}
+
+/**
+ * pci_pri_supported - Check if PRI is supported.
+ * @pdev: PCI device structure
+ *
+ * Returns true if PRI capability is present, false otherwise.
+ */
+bool pci_pri_supported(struct pci_dev *pdev)
+{
+ /* VFs share the PF PRI */
+ if (pci_physfn(pdev)->pri_cap)
+ return true;
+ return false;
+}
+EXPORT_SYMBOL_GPL(pci_pri_supported);
+#endif /* CONFIG_PCI_PRI */
+
+#ifdef CONFIG_PCI_PASID
+void pci_pasid_init(struct pci_dev *pdev)
+{
+ pdev->pasid_cap = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
+}
+
+/**
+ * pci_enable_pasid - Enable the PASID capability
+ * @pdev: PCI device structure
+ * @features: Features to enable
+ *
+ * Returns 0 on success, negative value on error. This function checks
+ * whether the features are actually supported by the device and returns
+ * an error if not.
+ */
+int pci_enable_pasid(struct pci_dev *pdev, int features)
+{
+ u16 control, supported;
+ int pasid = pdev->pasid_cap;
+
+ /*
+ * VFs must not implement the PASID Capability, but if a PF
+ * supports PASID, its VFs share the PF PASID configuration.
+ */
+ if (pdev->is_virtfn) {
+ if (pci_physfn(pdev)->pasid_enabled)
+ return 0;
+ return -EINVAL;
+ }
+
+ if (WARN_ON(pdev->pasid_enabled))
+ return -EBUSY;
+
+ if (!pdev->eetlp_prefix_path && !pdev->pasid_no_tlp)
+ return -EINVAL;
+
+ if (!pasid)
+ return -EINVAL;
+
+ if (!pci_acs_path_enabled(pdev, NULL, PCI_ACS_RR | PCI_ACS_UF))
+ return -EINVAL;
+
+ pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
+ supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
+
+ /* User wants to enable anything unsupported? */
+ if ((supported & features) != features)
+ return -EINVAL;
+
+ control = PCI_PASID_CTRL_ENABLE | features;
+ pdev->pasid_features = features;
+
+ pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
+
+ pdev->pasid_enabled = 1;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pci_enable_pasid);
+
+/**
+ * pci_disable_pasid - Disable the PASID capability
+ * @pdev: PCI device structure
+ */
+void pci_disable_pasid(struct pci_dev *pdev)
+{
+ u16 control = 0;
+ int pasid = pdev->pasid_cap;
+
+ /* VFs share the PF PASID configuration */
+ if (pdev->is_virtfn)
+ return;
+
+ if (WARN_ON(!pdev->pasid_enabled))
+ return;
+
+ if (!pasid)
+ return;
+
+ pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
+
+ pdev->pasid_enabled = 0;
+}
+EXPORT_SYMBOL_GPL(pci_disable_pasid);
+
+/**
+ * pci_restore_pasid_state - Restore PASID capabilities
+ * @pdev: PCI device structure
+ */
+void pci_restore_pasid_state(struct pci_dev *pdev)
+{
+ u16 control;
+ int pasid = pdev->pasid_cap;
+
+ if (pdev->is_virtfn)
+ return;
+
+ if (!pdev->pasid_enabled)
+ return;
+
+ if (!pasid)
+ return;
+
+ control = PCI_PASID_CTRL_ENABLE | pdev->pasid_features;
+ pci_write_config_word(pdev, pasid + PCI_PASID_CTRL, control);
+}
+
+/**
+ * pci_pasid_features - Check which PASID features are supported
+ * @pdev: PCI device structure
+ *
+ * Returns a negative value when no PASI capability is present.
+ * Otherwise is returns a bitmask with supported features. Current
+ * features reported are:
+ * PCI_PASID_CAP_EXEC - Execute permission supported
+ * PCI_PASID_CAP_PRIV - Privileged mode supported
+ */
+int pci_pasid_features(struct pci_dev *pdev)
+{
+ u16 supported;
+ int pasid;
+
+ if (pdev->is_virtfn)
+ pdev = pci_physfn(pdev);
+
+ pasid = pdev->pasid_cap;
+ if (!pasid)
+ return -EINVAL;
+
+ pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
+
+ supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
+
+ return supported;
+}
+EXPORT_SYMBOL_GPL(pci_pasid_features);
+
+#define PASID_NUMBER_SHIFT 8
+#define PASID_NUMBER_MASK (0x1f << PASID_NUMBER_SHIFT)
+/**
+ * pci_max_pasids - Get maximum number of PASIDs supported by device
+ * @pdev: PCI device structure
+ *
+ * Returns negative value when PASID capability is not present.
+ * Otherwise it returns the number of supported PASIDs.
+ */
+int pci_max_pasids(struct pci_dev *pdev)
+{
+ u16 supported;
+ int pasid;
+
+ if (pdev->is_virtfn)
+ pdev = pci_physfn(pdev);
+
+ pasid = pdev->pasid_cap;
+ if (!pasid)
+ return -EINVAL;
+
+ pci_read_config_word(pdev, pasid + PCI_PASID_CAP, &supported);
+
+ supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT;
+
+ return (1 << supported);
+}
+EXPORT_SYMBOL_GPL(pci_max_pasids);
+#endif /* CONFIG_PCI_PASID */