From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- drivers/pci/access.c | 588 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 588 insertions(+) create mode 100644 drivers/pci/access.c (limited to 'drivers/pci/access.c') diff --git a/drivers/pci/access.c b/drivers/pci/access.c new file mode 100644 index 000000000..3c230ca3d --- /dev/null +++ b/drivers/pci/access.c @@ -0,0 +1,588 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +#include "pci.h" + +/* + * This interrupt-safe spinlock protects all accesses to PCI + * configuration space. + */ + +DEFINE_RAW_SPINLOCK(pci_lock); + +/* + * Wrappers for all PCI configuration access functions. They just check + * alignment, do locking and call the low-level functions pointed to + * by pci_dev->ops. + */ + +#define PCI_byte_BAD 0 +#define PCI_word_BAD (pos & 1) +#define PCI_dword_BAD (pos & 3) + +#ifdef CONFIG_PCI_LOCKLESS_CONFIG +# define pci_lock_config(f) do { (void)(f); } while (0) +# define pci_unlock_config(f) do { (void)(f); } while (0) +#else +# define pci_lock_config(f) raw_spin_lock_irqsave(&pci_lock, f) +# define pci_unlock_config(f) raw_spin_unlock_irqrestore(&pci_lock, f) +#endif + +#define PCI_OP_READ(size, type, len) \ +int noinline pci_bus_read_config_##size \ + (struct pci_bus *bus, unsigned int devfn, int pos, type *value) \ +{ \ + int res; \ + unsigned long flags; \ + u32 data = 0; \ + if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; \ + pci_lock_config(flags); \ + res = bus->ops->read(bus, devfn, pos, len, &data); \ + if (res) \ + PCI_SET_ERROR_RESPONSE(value); \ + else \ + *value = (type)data; \ + pci_unlock_config(flags); \ + return res; \ +} + +#define PCI_OP_WRITE(size, type, len) \ +int noinline pci_bus_write_config_##size \ + (struct pci_bus *bus, unsigned int devfn, int pos, type value) \ +{ \ + int res; \ + unsigned long flags; \ + if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER; \ + pci_lock_config(flags); \ + res = bus->ops->write(bus, devfn, pos, len, value); \ + pci_unlock_config(flags); \ + return res; \ +} + +PCI_OP_READ(byte, u8, 1) +PCI_OP_READ(word, u16, 2) +PCI_OP_READ(dword, u32, 4) +PCI_OP_WRITE(byte, u8, 1) +PCI_OP_WRITE(word, u16, 2) +PCI_OP_WRITE(dword, u32, 4) + +EXPORT_SYMBOL(pci_bus_read_config_byte); +EXPORT_SYMBOL(pci_bus_read_config_word); +EXPORT_SYMBOL(pci_bus_read_config_dword); +EXPORT_SYMBOL(pci_bus_write_config_byte); +EXPORT_SYMBOL(pci_bus_write_config_word); +EXPORT_SYMBOL(pci_bus_write_config_dword); + +int pci_generic_config_read(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + void __iomem *addr; + + addr = bus->ops->map_bus(bus, devfn, where); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (size == 1) + *val = readb(addr); + else if (size == 2) + *val = readw(addr); + else + *val = readl(addr); + + return PCIBIOS_SUCCESSFUL; +} +EXPORT_SYMBOL_GPL(pci_generic_config_read); + +int pci_generic_config_write(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + void __iomem *addr; + + addr = bus->ops->map_bus(bus, devfn, where); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (size == 1) + writeb(val, addr); + else if (size == 2) + writew(val, addr); + else + writel(val, addr); + + return PCIBIOS_SUCCESSFUL; +} +EXPORT_SYMBOL_GPL(pci_generic_config_write); + +int pci_generic_config_read32(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 *val) +{ + void __iomem *addr; + + addr = bus->ops->map_bus(bus, devfn, where & ~0x3); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + *val = readl(addr); + + if (size <= 2) + *val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1); + + return PCIBIOS_SUCCESSFUL; +} +EXPORT_SYMBOL_GPL(pci_generic_config_read32); + +int pci_generic_config_write32(struct pci_bus *bus, unsigned int devfn, + int where, int size, u32 val) +{ + void __iomem *addr; + u32 mask, tmp; + + addr = bus->ops->map_bus(bus, devfn, where & ~0x3); + if (!addr) + return PCIBIOS_DEVICE_NOT_FOUND; + + if (size == 4) { + writel(val, addr); + return PCIBIOS_SUCCESSFUL; + } + + /* + * In general, hardware that supports only 32-bit writes on PCI is + * not spec-compliant. For example, software may perform a 16-bit + * write. If the hardware only supports 32-bit accesses, we must + * do a 32-bit read, merge in the 16 bits we intend to write, + * followed by a 32-bit write. If the 16 bits we *don't* intend to + * write happen to have any RW1C (write-one-to-clear) bits set, we + * just inadvertently cleared something we shouldn't have. + */ + if (!bus->unsafe_warn) { + dev_warn(&bus->dev, "%d-byte config write to %04x:%02x:%02x.%d offset %#x may corrupt adjacent RW1C bits\n", + size, pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), where); + bus->unsafe_warn = 1; + } + + mask = ~(((1 << (size * 8)) - 1) << ((where & 0x3) * 8)); + tmp = readl(addr) & mask; + tmp |= val << ((where & 0x3) * 8); + writel(tmp, addr); + + return PCIBIOS_SUCCESSFUL; +} +EXPORT_SYMBOL_GPL(pci_generic_config_write32); + +/** + * pci_bus_set_ops - Set raw operations of pci bus + * @bus: pci bus struct + * @ops: new raw operations + * + * Return previous raw operations + */ +struct pci_ops *pci_bus_set_ops(struct pci_bus *bus, struct pci_ops *ops) +{ + struct pci_ops *old_ops; + unsigned long flags; + + raw_spin_lock_irqsave(&pci_lock, flags); + old_ops = bus->ops; + bus->ops = ops; + raw_spin_unlock_irqrestore(&pci_lock, flags); + return old_ops; +} +EXPORT_SYMBOL(pci_bus_set_ops); + +/* + * The following routines are to prevent the user from accessing PCI config + * space when it's unsafe to do so. Some devices require this during BIST and + * we're required to prevent it during D-state transitions. + * + * We have a bit per device to indicate it's blocked and a global wait queue + * for callers to sleep on until devices are unblocked. + */ +static DECLARE_WAIT_QUEUE_HEAD(pci_cfg_wait); + +static noinline void pci_wait_cfg(struct pci_dev *dev) + __must_hold(&pci_lock) +{ + do { + raw_spin_unlock_irq(&pci_lock); + wait_event(pci_cfg_wait, !dev->block_cfg_access); + raw_spin_lock_irq(&pci_lock); + } while (dev->block_cfg_access); +} + +/* Returns 0 on success, negative values indicate error. */ +#define PCI_USER_READ_CONFIG(size, type) \ +int pci_user_read_config_##size \ + (struct pci_dev *dev, int pos, type *val) \ +{ \ + int ret = PCIBIOS_SUCCESSFUL; \ + u32 data = -1; \ + if (PCI_##size##_BAD) \ + return -EINVAL; \ + raw_spin_lock_irq(&pci_lock); \ + if (unlikely(dev->block_cfg_access)) \ + pci_wait_cfg(dev); \ + ret = dev->bus->ops->read(dev->bus, dev->devfn, \ + pos, sizeof(type), &data); \ + raw_spin_unlock_irq(&pci_lock); \ + if (ret) \ + PCI_SET_ERROR_RESPONSE(val); \ + else \ + *val = (type)data; \ + return pcibios_err_to_errno(ret); \ +} \ +EXPORT_SYMBOL_GPL(pci_user_read_config_##size); + +/* Returns 0 on success, negative values indicate error. */ +#define PCI_USER_WRITE_CONFIG(size, type) \ +int pci_user_write_config_##size \ + (struct pci_dev *dev, int pos, type val) \ +{ \ + int ret = PCIBIOS_SUCCESSFUL; \ + if (PCI_##size##_BAD) \ + return -EINVAL; \ + raw_spin_lock_irq(&pci_lock); \ + if (unlikely(dev->block_cfg_access)) \ + pci_wait_cfg(dev); \ + ret = dev->bus->ops->write(dev->bus, dev->devfn, \ + pos, sizeof(type), val); \ + raw_spin_unlock_irq(&pci_lock); \ + return pcibios_err_to_errno(ret); \ +} \ +EXPORT_SYMBOL_GPL(pci_user_write_config_##size); + +PCI_USER_READ_CONFIG(byte, u8) +PCI_USER_READ_CONFIG(word, u16) +PCI_USER_READ_CONFIG(dword, u32) +PCI_USER_WRITE_CONFIG(byte, u8) +PCI_USER_WRITE_CONFIG(word, u16) +PCI_USER_WRITE_CONFIG(dword, u32) + +/** + * pci_cfg_access_lock - Lock PCI config reads/writes + * @dev: pci device struct + * + * When access is locked, any userspace reads or writes to config + * space and concurrent lock requests will sleep until access is + * allowed via pci_cfg_access_unlock() again. + */ +void pci_cfg_access_lock(struct pci_dev *dev) +{ + might_sleep(); + + raw_spin_lock_irq(&pci_lock); + if (dev->block_cfg_access) + pci_wait_cfg(dev); + dev->block_cfg_access = 1; + raw_spin_unlock_irq(&pci_lock); +} +EXPORT_SYMBOL_GPL(pci_cfg_access_lock); + +/** + * pci_cfg_access_trylock - try to lock PCI config reads/writes + * @dev: pci device struct + * + * Same as pci_cfg_access_lock, but will return 0 if access is + * already locked, 1 otherwise. This function can be used from + * atomic contexts. + */ +bool pci_cfg_access_trylock(struct pci_dev *dev) +{ + unsigned long flags; + bool locked = true; + + raw_spin_lock_irqsave(&pci_lock, flags); + if (dev->block_cfg_access) + locked = false; + else + dev->block_cfg_access = 1; + raw_spin_unlock_irqrestore(&pci_lock, flags); + + return locked; +} +EXPORT_SYMBOL_GPL(pci_cfg_access_trylock); + +/** + * pci_cfg_access_unlock - Unlock PCI config reads/writes + * @dev: pci device struct + * + * This function allows PCI config accesses to resume. + */ +void pci_cfg_access_unlock(struct pci_dev *dev) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&pci_lock, flags); + + /* + * This indicates a problem in the caller, but we don't need + * to kill them, unlike a double-block above. + */ + WARN_ON(!dev->block_cfg_access); + + dev->block_cfg_access = 0; + raw_spin_unlock_irqrestore(&pci_lock, flags); + + wake_up_all(&pci_cfg_wait); +} +EXPORT_SYMBOL_GPL(pci_cfg_access_unlock); + +static inline int pcie_cap_version(const struct pci_dev *dev) +{ + return pcie_caps_reg(dev) & PCI_EXP_FLAGS_VERS; +} + +bool pcie_cap_has_lnkctl(const struct pci_dev *dev) +{ + int type = pci_pcie_type(dev); + + return type == PCI_EXP_TYPE_ENDPOINT || + type == PCI_EXP_TYPE_LEG_END || + type == PCI_EXP_TYPE_ROOT_PORT || + type == PCI_EXP_TYPE_UPSTREAM || + type == PCI_EXP_TYPE_DOWNSTREAM || + type == PCI_EXP_TYPE_PCI_BRIDGE || + type == PCI_EXP_TYPE_PCIE_BRIDGE; +} + +bool pcie_cap_has_lnkctl2(const struct pci_dev *dev) +{ + return pcie_cap_has_lnkctl(dev) && pcie_cap_version(dev) > 1; +} + +static inline bool pcie_cap_has_sltctl(const struct pci_dev *dev) +{ + return pcie_downstream_port(dev) && + pcie_caps_reg(dev) & PCI_EXP_FLAGS_SLOT; +} + +bool pcie_cap_has_rtctl(const struct pci_dev *dev) +{ + int type = pci_pcie_type(dev); + + return type == PCI_EXP_TYPE_ROOT_PORT || + type == PCI_EXP_TYPE_RC_EC; +} + +static bool pcie_capability_reg_implemented(struct pci_dev *dev, int pos) +{ + if (!pci_is_pcie(dev)) + return false; + + switch (pos) { + case PCI_EXP_FLAGS: + return true; + case PCI_EXP_DEVCAP: + case PCI_EXP_DEVCTL: + case PCI_EXP_DEVSTA: + return true; + case PCI_EXP_LNKCAP: + case PCI_EXP_LNKCTL: + case PCI_EXP_LNKSTA: + return pcie_cap_has_lnkctl(dev); + case PCI_EXP_SLTCAP: + case PCI_EXP_SLTCTL: + case PCI_EXP_SLTSTA: + return pcie_cap_has_sltctl(dev); + case PCI_EXP_RTCTL: + case PCI_EXP_RTCAP: + case PCI_EXP_RTSTA: + return pcie_cap_has_rtctl(dev); + case PCI_EXP_DEVCAP2: + case PCI_EXP_DEVCTL2: + return pcie_cap_version(dev) > 1; + case PCI_EXP_LNKCAP2: + case PCI_EXP_LNKCTL2: + case PCI_EXP_LNKSTA2: + return pcie_cap_has_lnkctl2(dev); + default: + return false; + } +} + +/* + * Note that these accessor functions are only for the "PCI Express + * Capability" (see PCIe spec r3.0, sec 7.8). They do not apply to the + * other "PCI Express Extended Capabilities" (AER, VC, ACS, MFVC, etc.) + */ +int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val) +{ + int ret; + + *val = 0; + if (pos & 1) + return PCIBIOS_BAD_REGISTER_NUMBER; + + if (pcie_capability_reg_implemented(dev, pos)) { + ret = pci_read_config_word(dev, pci_pcie_cap(dev) + pos, val); + /* + * Reset *val to 0 if pci_read_config_word() fails; it may + * have been written as 0xFFFF (PCI_ERROR_RESPONSE) if the + * config read failed on PCI. + */ + if (ret) + *val = 0; + return ret; + } + + /* + * For Functions that do not implement the Slot Capabilities, + * Slot Status, and Slot Control registers, these spaces must + * be hardwired to 0b, with the exception of the Presence Detect + * State bit in the Slot Status register of Downstream Ports, + * which must be hardwired to 1b. (PCIe Base Spec 3.0, sec 7.8) + */ + if (pci_is_pcie(dev) && pcie_downstream_port(dev) && + pos == PCI_EXP_SLTSTA) + *val = PCI_EXP_SLTSTA_PDS; + + return 0; +} +EXPORT_SYMBOL(pcie_capability_read_word); + +int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val) +{ + int ret; + + *val = 0; + if (pos & 3) + return PCIBIOS_BAD_REGISTER_NUMBER; + + if (pcie_capability_reg_implemented(dev, pos)) { + ret = pci_read_config_dword(dev, pci_pcie_cap(dev) + pos, val); + /* + * Reset *val to 0 if pci_read_config_dword() fails; it may + * have been written as 0xFFFFFFFF (PCI_ERROR_RESPONSE) if + * the config read failed on PCI. + */ + if (ret) + *val = 0; + return ret; + } + + if (pci_is_pcie(dev) && pcie_downstream_port(dev) && + pos == PCI_EXP_SLTSTA) + *val = PCI_EXP_SLTSTA_PDS; + + return 0; +} +EXPORT_SYMBOL(pcie_capability_read_dword); + +int pcie_capability_write_word(struct pci_dev *dev, int pos, u16 val) +{ + if (pos & 1) + return PCIBIOS_BAD_REGISTER_NUMBER; + + if (!pcie_capability_reg_implemented(dev, pos)) + return 0; + + return pci_write_config_word(dev, pci_pcie_cap(dev) + pos, val); +} +EXPORT_SYMBOL(pcie_capability_write_word); + +int pcie_capability_write_dword(struct pci_dev *dev, int pos, u32 val) +{ + if (pos & 3) + return PCIBIOS_BAD_REGISTER_NUMBER; + + if (!pcie_capability_reg_implemented(dev, pos)) + return 0; + + return pci_write_config_dword(dev, pci_pcie_cap(dev) + pos, val); +} +EXPORT_SYMBOL(pcie_capability_write_dword); + +int pcie_capability_clear_and_set_word(struct pci_dev *dev, int pos, + u16 clear, u16 set) +{ + int ret; + u16 val; + + ret = pcie_capability_read_word(dev, pos, &val); + if (!ret) { + val &= ~clear; + val |= set; + ret = pcie_capability_write_word(dev, pos, val); + } + + return ret; +} +EXPORT_SYMBOL(pcie_capability_clear_and_set_word); + +int pcie_capability_clear_and_set_dword(struct pci_dev *dev, int pos, + u32 clear, u32 set) +{ + int ret; + u32 val; + + ret = pcie_capability_read_dword(dev, pos, &val); + if (!ret) { + val &= ~clear; + val |= set; + ret = pcie_capability_write_dword(dev, pos, val); + } + + return ret; +} +EXPORT_SYMBOL(pcie_capability_clear_and_set_dword); + +int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val) +{ + if (pci_dev_is_disconnected(dev)) { + PCI_SET_ERROR_RESPONSE(val); + return PCIBIOS_DEVICE_NOT_FOUND; + } + return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_read_config_byte); + +int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val) +{ + if (pci_dev_is_disconnected(dev)) { + PCI_SET_ERROR_RESPONSE(val); + return PCIBIOS_DEVICE_NOT_FOUND; + } + return pci_bus_read_config_word(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_read_config_word); + +int pci_read_config_dword(const struct pci_dev *dev, int where, + u32 *val) +{ + if (pci_dev_is_disconnected(dev)) { + PCI_SET_ERROR_RESPONSE(val); + return PCIBIOS_DEVICE_NOT_FOUND; + } + return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_read_config_dword); + +int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val) +{ + if (pci_dev_is_disconnected(dev)) + return PCIBIOS_DEVICE_NOT_FOUND; + return pci_bus_write_config_byte(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_write_config_byte); + +int pci_write_config_word(const struct pci_dev *dev, int where, u16 val) +{ + if (pci_dev_is_disconnected(dev)) + return PCIBIOS_DEVICE_NOT_FOUND; + return pci_bus_write_config_word(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_write_config_word); + +int pci_write_config_dword(const struct pci_dev *dev, int where, + u32 val) +{ + if (pci_dev_is_disconnected(dev)) + return PCIBIOS_DEVICE_NOT_FOUND; + return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val); +} +EXPORT_SYMBOL(pci_write_config_dword); -- cgit v1.2.3