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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/vc.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/vc.c')
-rw-r--r--drivers/pci/vc.c428
1 files changed, 428 insertions, 0 deletions
diff --git a/drivers/pci/vc.c b/drivers/pci/vc.c
new file mode 100644
index 000000000..5fc59ac31
--- /dev/null
+++ b/drivers/pci/vc.c
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI Virtual Channel support
+ *
+ * Copyright (C) 2013 Red Hat, Inc. All rights reserved.
+ * Author: Alex Williamson <alex.williamson@redhat.com>
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <linux/types.h>
+
+#include "pci.h"
+
+/**
+ * pci_vc_save_restore_dwords - Save or restore a series of dwords
+ * @dev: device
+ * @pos: starting config space position
+ * @buf: buffer to save to or restore from
+ * @dwords: number of dwords to save/restore
+ * @save: whether to save or restore
+ */
+static void pci_vc_save_restore_dwords(struct pci_dev *dev, int pos,
+ u32 *buf, int dwords, bool save)
+{
+ int i;
+
+ for (i = 0; i < dwords; i++, buf++) {
+ if (save)
+ pci_read_config_dword(dev, pos + (i * 4), buf);
+ else
+ pci_write_config_dword(dev, pos + (i * 4), *buf);
+ }
+}
+
+/**
+ * pci_vc_load_arb_table - load and wait for VC arbitration table
+ * @dev: device
+ * @pos: starting position of VC capability (VC/VC9/MFVC)
+ *
+ * Set Load VC Arbitration Table bit requesting hardware to apply the VC
+ * Arbitration Table (previously loaded). When the VC Arbitration Table
+ * Status clears, hardware has latched the table into VC arbitration logic.
+ */
+static void pci_vc_load_arb_table(struct pci_dev *dev, int pos)
+{
+ u16 ctrl;
+
+ pci_read_config_word(dev, pos + PCI_VC_PORT_CTRL, &ctrl);
+ pci_write_config_word(dev, pos + PCI_VC_PORT_CTRL,
+ ctrl | PCI_VC_PORT_CTRL_LOAD_TABLE);
+ if (pci_wait_for_pending(dev, pos + PCI_VC_PORT_STATUS,
+ PCI_VC_PORT_STATUS_TABLE))
+ return;
+
+ pci_err(dev, "VC arbitration table failed to load\n");
+}
+
+/**
+ * pci_vc_load_port_arb_table - Load and wait for VC port arbitration table
+ * @dev: device
+ * @pos: starting position of VC capability (VC/VC9/MFVC)
+ * @res: VC resource number, ie. VCn (0-7)
+ *
+ * Set Load Port Arbitration Table bit requesting hardware to apply the Port
+ * Arbitration Table (previously loaded). When the Port Arbitration Table
+ * Status clears, hardware has latched the table into port arbitration logic.
+ */
+static void pci_vc_load_port_arb_table(struct pci_dev *dev, int pos, int res)
+{
+ int ctrl_pos, status_pos;
+ u32 ctrl;
+
+ ctrl_pos = pos + PCI_VC_RES_CTRL + (res * PCI_CAP_VC_PER_VC_SIZEOF);
+ status_pos = pos + PCI_VC_RES_STATUS + (res * PCI_CAP_VC_PER_VC_SIZEOF);
+
+ pci_read_config_dword(dev, ctrl_pos, &ctrl);
+ pci_write_config_dword(dev, ctrl_pos,
+ ctrl | PCI_VC_RES_CTRL_LOAD_TABLE);
+
+ if (pci_wait_for_pending(dev, status_pos, PCI_VC_RES_STATUS_TABLE))
+ return;
+
+ pci_err(dev, "VC%d port arbitration table failed to load\n", res);
+}
+
+/**
+ * pci_vc_enable - Enable virtual channel
+ * @dev: device
+ * @pos: starting position of VC capability (VC/VC9/MFVC)
+ * @res: VC res number, ie. VCn (0-7)
+ *
+ * A VC is enabled by setting the enable bit in matching resource control
+ * registers on both sides of a link. We therefore need to find the opposite
+ * end of the link. To keep this simple we enable from the downstream device.
+ * RC devices do not have an upstream device, nor does it seem that VC9 do
+ * (spec is unclear). Once we find the upstream device, match the VC ID to
+ * get the correct resource, disable and enable on both ends.
+ */
+static void pci_vc_enable(struct pci_dev *dev, int pos, int res)
+{
+ int ctrl_pos, status_pos, id, pos2, evcc, i, ctrl_pos2, status_pos2;
+ u32 ctrl, header, cap1, ctrl2;
+ struct pci_dev *link = NULL;
+
+ /* Enable VCs from the downstream device */
+ if (!pci_is_pcie(dev) || !pcie_downstream_port(dev))
+ return;
+
+ ctrl_pos = pos + PCI_VC_RES_CTRL + (res * PCI_CAP_VC_PER_VC_SIZEOF);
+ status_pos = pos + PCI_VC_RES_STATUS + (res * PCI_CAP_VC_PER_VC_SIZEOF);
+
+ pci_read_config_dword(dev, ctrl_pos, &ctrl);
+ id = ctrl & PCI_VC_RES_CTRL_ID;
+
+ pci_read_config_dword(dev, pos, &header);
+
+ /* If there is no opposite end of the link, skip to enable */
+ if (PCI_EXT_CAP_ID(header) == PCI_EXT_CAP_ID_VC9 ||
+ pci_is_root_bus(dev->bus))
+ goto enable;
+
+ pos2 = pci_find_ext_capability(dev->bus->self, PCI_EXT_CAP_ID_VC);
+ if (!pos2)
+ goto enable;
+
+ pci_read_config_dword(dev->bus->self, pos2 + PCI_VC_PORT_CAP1, &cap1);
+ evcc = cap1 & PCI_VC_CAP1_EVCC;
+
+ /* VC0 is hardwired enabled, so we can start with 1 */
+ for (i = 1; i < evcc + 1; i++) {
+ ctrl_pos2 = pos2 + PCI_VC_RES_CTRL +
+ (i * PCI_CAP_VC_PER_VC_SIZEOF);
+ status_pos2 = pos2 + PCI_VC_RES_STATUS +
+ (i * PCI_CAP_VC_PER_VC_SIZEOF);
+ pci_read_config_dword(dev->bus->self, ctrl_pos2, &ctrl2);
+ if ((ctrl2 & PCI_VC_RES_CTRL_ID) == id) {
+ link = dev->bus->self;
+ break;
+ }
+ }
+
+ if (!link)
+ goto enable;
+
+ /* Disable if enabled */
+ if (ctrl2 & PCI_VC_RES_CTRL_ENABLE) {
+ ctrl2 &= ~PCI_VC_RES_CTRL_ENABLE;
+ pci_write_config_dword(link, ctrl_pos2, ctrl2);
+ }
+
+ /* Enable on both ends */
+ ctrl2 |= PCI_VC_RES_CTRL_ENABLE;
+ pci_write_config_dword(link, ctrl_pos2, ctrl2);
+enable:
+ ctrl |= PCI_VC_RES_CTRL_ENABLE;
+ pci_write_config_dword(dev, ctrl_pos, ctrl);
+
+ if (!pci_wait_for_pending(dev, status_pos, PCI_VC_RES_STATUS_NEGO))
+ pci_err(dev, "VC%d negotiation stuck pending\n", id);
+
+ if (link && !pci_wait_for_pending(link, status_pos2,
+ PCI_VC_RES_STATUS_NEGO))
+ pci_err(link, "VC%d negotiation stuck pending\n", id);
+}
+
+/**
+ * pci_vc_do_save_buffer - Size, save, or restore VC state
+ * @dev: device
+ * @pos: starting position of VC capability (VC/VC9/MFVC)
+ * @save_state: buffer for save/restore
+ * @save: if provided a buffer, this indicates what to do with it
+ *
+ * Walking Virtual Channel config space to size, save, or restore it
+ * is complicated, so we do it all from one function to reduce code and
+ * guarantee ordering matches in the buffer. When called with NULL
+ * @save_state, return the size of the necessary save buffer. When called
+ * with a non-NULL @save_state, @save determines whether we save to the
+ * buffer or restore from it.
+ */
+static int pci_vc_do_save_buffer(struct pci_dev *dev, int pos,
+ struct pci_cap_saved_state *save_state,
+ bool save)
+{
+ u32 cap1;
+ char evcc, lpevcc, parb_size;
+ int i, len = 0;
+ u8 *buf = save_state ? (u8 *)save_state->cap.data : NULL;
+
+ /* Sanity check buffer size for save/restore */
+ if (buf && save_state->cap.size !=
+ pci_vc_do_save_buffer(dev, pos, NULL, save)) {
+ pci_err(dev, "VC save buffer size does not match @0x%x\n", pos);
+ return -ENOMEM;
+ }
+
+ pci_read_config_dword(dev, pos + PCI_VC_PORT_CAP1, &cap1);
+ /* Extended VC Count (not counting VC0) */
+ evcc = cap1 & PCI_VC_CAP1_EVCC;
+ /* Low Priority Extended VC Count (not counting VC0) */
+ lpevcc = (cap1 & PCI_VC_CAP1_LPEVCC) >> 4;
+ /* Port Arbitration Table Entry Size (bits) */
+ parb_size = 1 << ((cap1 & PCI_VC_CAP1_ARB_SIZE) >> 10);
+
+ /*
+ * Port VC Control Register contains VC Arbitration Select, which
+ * cannot be modified when more than one LPVC is in operation. We
+ * therefore save/restore it first, as only VC0 should be enabled
+ * after device reset.
+ */
+ if (buf) {
+ if (save)
+ pci_read_config_word(dev, pos + PCI_VC_PORT_CTRL,
+ (u16 *)buf);
+ else
+ pci_write_config_word(dev, pos + PCI_VC_PORT_CTRL,
+ *(u16 *)buf);
+ buf += 4;
+ }
+ len += 4;
+
+ /*
+ * If we have any Low Priority VCs and a VC Arbitration Table Offset
+ * in Port VC Capability Register 2 then save/restore it next.
+ */
+ if (lpevcc) {
+ u32 cap2;
+ int vcarb_offset;
+
+ pci_read_config_dword(dev, pos + PCI_VC_PORT_CAP2, &cap2);
+ vcarb_offset = ((cap2 & PCI_VC_CAP2_ARB_OFF) >> 24) * 16;
+
+ if (vcarb_offset) {
+ int size, vcarb_phases = 0;
+
+ if (cap2 & PCI_VC_CAP2_128_PHASE)
+ vcarb_phases = 128;
+ else if (cap2 & PCI_VC_CAP2_64_PHASE)
+ vcarb_phases = 64;
+ else if (cap2 & PCI_VC_CAP2_32_PHASE)
+ vcarb_phases = 32;
+
+ /* Fixed 4 bits per phase per lpevcc (plus VC0) */
+ size = ((lpevcc + 1) * vcarb_phases * 4) / 8;
+
+ if (size && buf) {
+ pci_vc_save_restore_dwords(dev,
+ pos + vcarb_offset,
+ (u32 *)buf,
+ size / 4, save);
+ /*
+ * On restore, we need to signal hardware to
+ * re-load the VC Arbitration Table.
+ */
+ if (!save)
+ pci_vc_load_arb_table(dev, pos);
+
+ buf += size;
+ }
+ len += size;
+ }
+ }
+
+ /*
+ * In addition to each VC Resource Control Register, we may have a
+ * Port Arbitration Table attached to each VC. The Port Arbitration
+ * Table Offset in each VC Resource Capability Register tells us if
+ * it exists. The entry size is global from the Port VC Capability
+ * Register1 above. The number of phases is determined per VC.
+ */
+ for (i = 0; i < evcc + 1; i++) {
+ u32 cap;
+ int parb_offset;
+
+ pci_read_config_dword(dev, pos + PCI_VC_RES_CAP +
+ (i * PCI_CAP_VC_PER_VC_SIZEOF), &cap);
+ parb_offset = ((cap & PCI_VC_RES_CAP_ARB_OFF) >> 24) * 16;
+ if (parb_offset) {
+ int size, parb_phases = 0;
+
+ if (cap & PCI_VC_RES_CAP_256_PHASE)
+ parb_phases = 256;
+ else if (cap & (PCI_VC_RES_CAP_128_PHASE |
+ PCI_VC_RES_CAP_128_PHASE_TB))
+ parb_phases = 128;
+ else if (cap & PCI_VC_RES_CAP_64_PHASE)
+ parb_phases = 64;
+ else if (cap & PCI_VC_RES_CAP_32_PHASE)
+ parb_phases = 32;
+
+ size = (parb_size * parb_phases) / 8;
+
+ if (size && buf) {
+ pci_vc_save_restore_dwords(dev,
+ pos + parb_offset,
+ (u32 *)buf,
+ size / 4, save);
+ buf += size;
+ }
+ len += size;
+ }
+
+ /* VC Resource Control Register */
+ if (buf) {
+ int ctrl_pos = pos + PCI_VC_RES_CTRL +
+ (i * PCI_CAP_VC_PER_VC_SIZEOF);
+ if (save)
+ pci_read_config_dword(dev, ctrl_pos,
+ (u32 *)buf);
+ else {
+ u32 tmp, ctrl = *(u32 *)buf;
+ /*
+ * For an FLR case, the VC config may remain.
+ * Preserve enable bit, restore the rest.
+ */
+ pci_read_config_dword(dev, ctrl_pos, &tmp);
+ tmp &= PCI_VC_RES_CTRL_ENABLE;
+ tmp |= ctrl & ~PCI_VC_RES_CTRL_ENABLE;
+ pci_write_config_dword(dev, ctrl_pos, tmp);
+ /* Load port arbitration table if used */
+ if (ctrl & PCI_VC_RES_CTRL_ARB_SELECT)
+ pci_vc_load_port_arb_table(dev, pos, i);
+ /* Re-enable if needed */
+ if ((ctrl ^ tmp) & PCI_VC_RES_CTRL_ENABLE)
+ pci_vc_enable(dev, pos, i);
+ }
+ buf += 4;
+ }
+ len += 4;
+ }
+
+ return buf ? 0 : len;
+}
+
+static struct {
+ u16 id;
+ const char *name;
+} vc_caps[] = { { PCI_EXT_CAP_ID_MFVC, "MFVC" },
+ { PCI_EXT_CAP_ID_VC, "VC" },
+ { PCI_EXT_CAP_ID_VC9, "VC9" } };
+
+/**
+ * pci_save_vc_state - Save VC state to pre-allocate save buffer
+ * @dev: device
+ *
+ * For each type of VC capability, VC/VC9/MFVC, find the capability and
+ * save it to the pre-allocated save buffer.
+ */
+int pci_save_vc_state(struct pci_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(vc_caps); i++) {
+ int pos, ret;
+ struct pci_cap_saved_state *save_state;
+
+ pos = pci_find_ext_capability(dev, vc_caps[i].id);
+ if (!pos)
+ continue;
+
+ save_state = pci_find_saved_ext_cap(dev, vc_caps[i].id);
+ if (!save_state) {
+ pci_err(dev, "%s buffer not found in %s\n",
+ vc_caps[i].name, __func__);
+ return -ENOMEM;
+ }
+
+ ret = pci_vc_do_save_buffer(dev, pos, save_state, true);
+ if (ret) {
+ pci_err(dev, "%s save unsuccessful %s\n",
+ vc_caps[i].name, __func__);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * pci_restore_vc_state - Restore VC state from save buffer
+ * @dev: device
+ *
+ * For each type of VC capability, VC/VC9/MFVC, find the capability and
+ * restore it from the previously saved buffer.
+ */
+void pci_restore_vc_state(struct pci_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(vc_caps); i++) {
+ int pos;
+ struct pci_cap_saved_state *save_state;
+
+ pos = pci_find_ext_capability(dev, vc_caps[i].id);
+ save_state = pci_find_saved_ext_cap(dev, vc_caps[i].id);
+ if (!save_state || !pos)
+ continue;
+
+ pci_vc_do_save_buffer(dev, pos, save_state, false);
+ }
+}
+
+/**
+ * pci_allocate_vc_save_buffers - Allocate save buffers for VC caps
+ * @dev: device
+ *
+ * For each type of VC capability, VC/VC9/MFVC, find the capability, size
+ * it, and allocate a buffer for save/restore.
+ */
+void pci_allocate_vc_save_buffers(struct pci_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(vc_caps); i++) {
+ int len, pos = pci_find_ext_capability(dev, vc_caps[i].id);
+
+ if (!pos)
+ continue;
+
+ len = pci_vc_do_save_buffer(dev, pos, NULL, false);
+ if (pci_add_ext_cap_save_buffer(dev, vc_caps[i].id, len))
+ pci_err(dev, "unable to preallocate %s save buffer\n",
+ vc_caps[i].name);
+ }
+}