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/cxl/pci.c | 672 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 672 insertions(+) create mode 100644 drivers/cxl/pci.c (limited to 'drivers/cxl/pci.c') diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c new file mode 100644 index 000000000..258004f34 --- /dev/null +++ b/drivers/cxl/pci.c @@ -0,0 +1,672 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. All rights reserved. */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "cxlmem.h" +#include "cxlpci.h" +#include "cxl.h" +#define CREATE_TRACE_POINTS +#include + +/** + * DOC: cxl pci + * + * This implements the PCI exclusive functionality for a CXL device as it is + * defined by the Compute Express Link specification. CXL devices may surface + * certain functionality even if it isn't CXL enabled. While this driver is + * focused around the PCI specific aspects of a CXL device, it binds to the + * specific CXL memory device class code, and therefore the implementation of + * cxl_pci is focused around CXL memory devices. + * + * The driver has several responsibilities, mainly: + * - Create the memX device and register on the CXL bus. + * - Enumerate device's register interface and map them. + * - Registers nvdimm bridge device with cxl_core. + * - Registers a CXL mailbox with cxl_core. + */ + +#define cxl_doorbell_busy(cxlds) \ + (readl((cxlds)->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET) & \ + CXLDEV_MBOX_CTRL_DOORBELL) + +/* CXL 2.0 - 8.2.8.4 */ +#define CXL_MAILBOX_TIMEOUT_MS (2 * HZ) + +/* + * CXL 2.0 ECN "Add Mailbox Ready Time" defines a capability field to + * dictate how long to wait for the mailbox to become ready. The new + * field allows the device to tell software the amount of time to wait + * before mailbox ready. This field per the spec theoretically allows + * for up to 255 seconds. 255 seconds is unreasonably long, its longer + * than the maximum SATA port link recovery wait. Default to 60 seconds + * until someone builds a CXL device that needs more time in practice. + */ +static unsigned short mbox_ready_timeout = 60; +module_param(mbox_ready_timeout, ushort, 0644); +MODULE_PARM_DESC(mbox_ready_timeout, "seconds to wait for mailbox ready"); + +static int cxl_pci_mbox_wait_for_doorbell(struct cxl_dev_state *cxlds) +{ + const unsigned long start = jiffies; + unsigned long end = start; + + while (cxl_doorbell_busy(cxlds)) { + end = jiffies; + + if (time_after(end, start + CXL_MAILBOX_TIMEOUT_MS)) { + /* Check again in case preempted before timeout test */ + if (!cxl_doorbell_busy(cxlds)) + break; + return -ETIMEDOUT; + } + cpu_relax(); + } + + dev_dbg(cxlds->dev, "Doorbell wait took %dms", + jiffies_to_msecs(end) - jiffies_to_msecs(start)); + return 0; +} + +#define cxl_err(dev, status, msg) \ + dev_err_ratelimited(dev, msg ", device state %s%s\n", \ + status & CXLMDEV_DEV_FATAL ? " fatal" : "", \ + status & CXLMDEV_FW_HALT ? " firmware-halt" : "") + +#define cxl_cmd_err(dev, cmd, status, msg) \ + dev_err_ratelimited(dev, msg " (opcode: %#x), device state %s%s\n", \ + (cmd)->opcode, \ + status & CXLMDEV_DEV_FATAL ? " fatal" : "", \ + status & CXLMDEV_FW_HALT ? " firmware-halt" : "") + +/** + * __cxl_pci_mbox_send_cmd() - Execute a mailbox command + * @cxlds: The device state to communicate with. + * @mbox_cmd: Command to send to the memory device. + * + * Context: Any context. Expects mbox_mutex to be held. + * Return: -ETIMEDOUT if timeout occurred waiting for completion. 0 on success. + * Caller should check the return code in @mbox_cmd to make sure it + * succeeded. + * + * This is a generic form of the CXL mailbox send command thus only using the + * registers defined by the mailbox capability ID - CXL 2.0 8.2.8.4. Memory + * devices, and perhaps other types of CXL devices may have further information + * available upon error conditions. Driver facilities wishing to send mailbox + * commands should use the wrapper command. + * + * The CXL spec allows for up to two mailboxes. The intention is for the primary + * mailbox to be OS controlled and the secondary mailbox to be used by system + * firmware. This allows the OS and firmware to communicate with the device and + * not need to coordinate with each other. The driver only uses the primary + * mailbox. + */ +static int __cxl_pci_mbox_send_cmd(struct cxl_dev_state *cxlds, + struct cxl_mbox_cmd *mbox_cmd) +{ + void __iomem *payload = cxlds->regs.mbox + CXLDEV_MBOX_PAYLOAD_OFFSET; + struct device *dev = cxlds->dev; + u64 cmd_reg, status_reg; + size_t out_len; + int rc; + + lockdep_assert_held(&cxlds->mbox_mutex); + + /* + * Here are the steps from 8.2.8.4 of the CXL 2.0 spec. + * 1. Caller reads MB Control Register to verify doorbell is clear + * 2. Caller writes Command Register + * 3. Caller writes Command Payload Registers if input payload is non-empty + * 4. Caller writes MB Control Register to set doorbell + * 5. Caller either polls for doorbell to be clear or waits for interrupt if configured + * 6. Caller reads MB Status Register to fetch Return code + * 7. If command successful, Caller reads Command Register to get Payload Length + * 8. If output payload is non-empty, host reads Command Payload Registers + * + * Hardware is free to do whatever it wants before the doorbell is rung, + * and isn't allowed to change anything after it clears the doorbell. As + * such, steps 2 and 3 can happen in any order, and steps 6, 7, 8 can + * also happen in any order (though some orders might not make sense). + */ + + /* #1 */ + if (cxl_doorbell_busy(cxlds)) { + u64 md_status = + readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); + + cxl_cmd_err(cxlds->dev, mbox_cmd, md_status, + "mailbox queue busy"); + return -EBUSY; + } + + cmd_reg = FIELD_PREP(CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK, + mbox_cmd->opcode); + if (mbox_cmd->size_in) { + if (WARN_ON(!mbox_cmd->payload_in)) + return -EINVAL; + + cmd_reg |= FIELD_PREP(CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK, + mbox_cmd->size_in); + memcpy_toio(payload, mbox_cmd->payload_in, mbox_cmd->size_in); + } + + /* #2, #3 */ + writeq(cmd_reg, cxlds->regs.mbox + CXLDEV_MBOX_CMD_OFFSET); + + /* #4 */ + dev_dbg(dev, "Sending command\n"); + writel(CXLDEV_MBOX_CTRL_DOORBELL, + cxlds->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET); + + /* #5 */ + rc = cxl_pci_mbox_wait_for_doorbell(cxlds); + if (rc == -ETIMEDOUT) { + u64 md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); + + cxl_cmd_err(cxlds->dev, mbox_cmd, md_status, "mailbox timeout"); + return rc; + } + + /* #6 */ + status_reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_STATUS_OFFSET); + mbox_cmd->return_code = + FIELD_GET(CXLDEV_MBOX_STATUS_RET_CODE_MASK, status_reg); + + if (mbox_cmd->return_code != CXL_MBOX_CMD_RC_SUCCESS) { + dev_dbg(dev, "Mailbox operation had an error: %s\n", + cxl_mbox_cmd_rc2str(mbox_cmd)); + return 0; /* completed but caller must check return_code */ + } + + /* #7 */ + cmd_reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_CMD_OFFSET); + out_len = FIELD_GET(CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK, cmd_reg); + + /* #8 */ + if (out_len && mbox_cmd->payload_out) { + /* + * Sanitize the copy. If hardware misbehaves, out_len per the + * spec can actually be greater than the max allowed size (21 + * bits available but spec defined 1M max). The caller also may + * have requested less data than the hardware supplied even + * within spec. + */ + size_t n = min3(mbox_cmd->size_out, cxlds->payload_size, out_len); + + memcpy_fromio(mbox_cmd->payload_out, payload, n); + mbox_cmd->size_out = n; + } else { + mbox_cmd->size_out = 0; + } + + return 0; +} + +static int cxl_pci_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd) +{ + int rc; + + mutex_lock_io(&cxlds->mbox_mutex); + rc = __cxl_pci_mbox_send_cmd(cxlds, cmd); + mutex_unlock(&cxlds->mbox_mutex); + + return rc; +} + +static int cxl_pci_setup_mailbox(struct cxl_dev_state *cxlds) +{ + const int cap = readl(cxlds->regs.mbox + CXLDEV_MBOX_CAPS_OFFSET); + unsigned long timeout; + u64 md_status; + + timeout = jiffies + mbox_ready_timeout * HZ; + do { + md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); + if (md_status & CXLMDEV_MBOX_IF_READY) + break; + if (msleep_interruptible(100)) + break; + } while (!time_after(jiffies, timeout)); + + if (!(md_status & CXLMDEV_MBOX_IF_READY)) { + cxl_err(cxlds->dev, md_status, + "timeout awaiting mailbox ready"); + return -ETIMEDOUT; + } + + /* + * A command may be in flight from a previous driver instance, + * think kexec, do one doorbell wait so that + * __cxl_pci_mbox_send_cmd() can assume that it is the only + * source for future doorbell busy events. + */ + if (cxl_pci_mbox_wait_for_doorbell(cxlds) != 0) { + cxl_err(cxlds->dev, md_status, "timeout awaiting mailbox idle"); + return -ETIMEDOUT; + } + + cxlds->mbox_send = cxl_pci_mbox_send; + cxlds->payload_size = + 1 << FIELD_GET(CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK, cap); + + /* + * CXL 2.0 8.2.8.4.3 Mailbox Capabilities Register + * + * If the size is too small, mandatory commands will not work and so + * there's no point in going forward. If the size is too large, there's + * no harm is soft limiting it. + */ + cxlds->payload_size = min_t(size_t, cxlds->payload_size, SZ_1M); + if (cxlds->payload_size < 256) { + dev_err(cxlds->dev, "Mailbox is too small (%zub)", + cxlds->payload_size); + return -ENXIO; + } + + dev_dbg(cxlds->dev, "Mailbox payload sized %zu", + cxlds->payload_size); + + return 0; +} + +static int cxl_map_regblock(struct pci_dev *pdev, struct cxl_register_map *map) +{ + struct device *dev = &pdev->dev; + + map->base = ioremap(map->resource, map->max_size); + if (!map->base) { + dev_err(dev, "failed to map registers\n"); + return -ENOMEM; + } + + dev_dbg(dev, "Mapped CXL Memory Device resource %pa\n", &map->resource); + return 0; +} + +static void cxl_unmap_regblock(struct pci_dev *pdev, + struct cxl_register_map *map) +{ + iounmap(map->base); + map->base = NULL; +} + +static int cxl_probe_regs(struct pci_dev *pdev, struct cxl_register_map *map) +{ + struct cxl_component_reg_map *comp_map; + struct cxl_device_reg_map *dev_map; + struct device *dev = &pdev->dev; + void __iomem *base = map->base; + + switch (map->reg_type) { + case CXL_REGLOC_RBI_COMPONENT: + comp_map = &map->component_map; + cxl_probe_component_regs(dev, base, comp_map); + if (!comp_map->hdm_decoder.valid) { + dev_err(dev, "HDM decoder registers not found\n"); + return -ENXIO; + } + + if (!comp_map->ras.valid) + dev_dbg(dev, "RAS registers not found\n"); + + dev_dbg(dev, "Set up component registers\n"); + break; + case CXL_REGLOC_RBI_MEMDEV: + dev_map = &map->device_map; + cxl_probe_device_regs(dev, base, dev_map); + if (!dev_map->status.valid || !dev_map->mbox.valid || + !dev_map->memdev.valid) { + dev_err(dev, "registers not found: %s%s%s\n", + !dev_map->status.valid ? "status " : "", + !dev_map->mbox.valid ? "mbox " : "", + !dev_map->memdev.valid ? "memdev " : ""); + return -ENXIO; + } + + dev_dbg(dev, "Probing device registers...\n"); + break; + default: + break; + } + + return 0; +} + +static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type, + struct cxl_register_map *map) +{ + int rc; + + rc = cxl_find_regblock(pdev, type, map); + if (rc) + return rc; + + rc = cxl_map_regblock(pdev, map); + if (rc) + return rc; + + rc = cxl_probe_regs(pdev, map); + cxl_unmap_regblock(pdev, map); + + return rc; +} + +static void cxl_pci_destroy_doe(void *mbs) +{ + xa_destroy(mbs); +} + +static void devm_cxl_pci_create_doe(struct cxl_dev_state *cxlds) +{ + struct device *dev = cxlds->dev; + struct pci_dev *pdev = to_pci_dev(dev); + u16 off = 0; + + xa_init(&cxlds->doe_mbs); + if (devm_add_action(&pdev->dev, cxl_pci_destroy_doe, &cxlds->doe_mbs)) { + dev_err(dev, "Failed to create XArray for DOE's\n"); + return; + } + + /* + * Mailbox creation is best effort. Higher layers must determine if + * the lack of a mailbox for their protocol is a device failure or not. + */ + pci_doe_for_each_off(pdev, off) { + struct pci_doe_mb *doe_mb; + + doe_mb = pcim_doe_create_mb(pdev, off); + if (IS_ERR(doe_mb)) { + dev_err(dev, "Failed to create MB object for MB @ %x\n", + off); + continue; + } + + if (!pci_request_config_region_exclusive(pdev, off, + PCI_DOE_CAP_SIZEOF, + dev_name(dev))) + pci_err(pdev, "Failed to exclude DOE registers\n"); + + if (xa_insert(&cxlds->doe_mbs, off, doe_mb, GFP_KERNEL)) { + dev_err(dev, "xa_insert failed to insert MB @ %x\n", + off); + continue; + } + + dev_dbg(dev, "Created DOE mailbox @%x\n", off); + } +} + +/* + * Assume that any RCIEP that emits the CXL memory expander class code + * is an RCD + */ +static bool is_cxl_restricted(struct pci_dev *pdev) +{ + return pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END; +} + +static void disable_aer(void *pdev) +{ + pci_disable_pcie_error_reporting(pdev); +} + +static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct cxl_register_map map; + struct cxl_memdev *cxlmd; + struct cxl_dev_state *cxlds; + int rc; + + /* + * Double check the anonymous union trickery in struct cxl_regs + * FIXME switch to struct_group() + */ + BUILD_BUG_ON(offsetof(struct cxl_regs, memdev) != + offsetof(struct cxl_regs, device_regs.memdev)); + + rc = pcim_enable_device(pdev); + if (rc) + return rc; + + cxlds = cxl_dev_state_create(&pdev->dev); + if (IS_ERR(cxlds)) + return PTR_ERR(cxlds); + pci_set_drvdata(pdev, cxlds); + + cxlds->rcd = is_cxl_restricted(pdev); + cxlds->serial = pci_get_dsn(pdev); + cxlds->cxl_dvsec = pci_find_dvsec_capability( + pdev, PCI_DVSEC_VENDOR_ID_CXL, CXL_DVSEC_PCIE_DEVICE); + if (!cxlds->cxl_dvsec) + dev_warn(&pdev->dev, + "Device DVSEC not present, skip CXL.mem init\n"); + + rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map); + if (rc) + return rc; + + rc = cxl_map_device_regs(&pdev->dev, &cxlds->regs.device_regs, &map); + if (rc) + return rc; + + /* + * If the component registers can't be found, the cxl_pci driver may + * still be useful for management functions so don't return an error. + */ + cxlds->component_reg_phys = CXL_RESOURCE_NONE; + rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &map); + if (rc) + dev_warn(&pdev->dev, "No component registers (%d)\n", rc); + + cxlds->component_reg_phys = map.resource; + + devm_cxl_pci_create_doe(cxlds); + + rc = cxl_map_component_regs(&pdev->dev, &cxlds->regs.component, + &map, BIT(CXL_CM_CAP_CAP_ID_RAS)); + if (rc) + dev_dbg(&pdev->dev, "Failed to map RAS capability.\n"); + + rc = cxl_pci_setup_mailbox(cxlds); + if (rc) + return rc; + + rc = cxl_enumerate_cmds(cxlds); + if (rc) + return rc; + + rc = cxl_dev_state_identify(cxlds); + if (rc) + return rc; + + rc = cxl_mem_create_range_info(cxlds); + if (rc) + return rc; + + cxlmd = devm_cxl_add_memdev(cxlds); + if (IS_ERR(cxlmd)) + return PTR_ERR(cxlmd); + + if (cxlds->regs.ras) { + pci_enable_pcie_error_reporting(pdev); + rc = devm_add_action_or_reset(&pdev->dev, disable_aer, pdev); + if (rc) + return rc; + } + pci_save_state(pdev); + + return rc; +} + +static const struct pci_device_id cxl_mem_pci_tbl[] = { + /* PCI class code for CXL.mem Type-3 Devices */ + { PCI_DEVICE_CLASS((PCI_CLASS_MEMORY_CXL << 8 | CXL_MEMORY_PROGIF), ~0)}, + { /* terminate list */ }, +}; +MODULE_DEVICE_TABLE(pci, cxl_mem_pci_tbl); + +/* CXL spec rev3.0 8.2.4.16.1 */ +static void header_log_copy(struct cxl_dev_state *cxlds, u32 *log) +{ + void __iomem *addr; + u32 *log_addr; + int i, log_u32_size = CXL_HEADERLOG_SIZE / sizeof(u32); + + addr = cxlds->regs.ras + CXL_RAS_HEADER_LOG_OFFSET; + log_addr = log; + + for (i = 0; i < log_u32_size; i++) { + *log_addr = readl(addr); + log_addr++; + addr += sizeof(u32); + } +} + +/* + * Log the state of the RAS status registers and prepare them to log the + * next error status. Return 1 if reset needed. + */ +static bool cxl_report_and_clear(struct cxl_dev_state *cxlds) +{ + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &cxlmd->dev; + u32 hl[CXL_HEADERLOG_SIZE_U32]; + void __iomem *addr; + u32 status; + u32 fe; + + if (!cxlds->regs.ras) + return false; + + addr = cxlds->regs.ras + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET; + status = readl(addr); + if (!(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK)) + return false; + + /* If multiple errors, log header points to first error from ctrl reg */ + if (hweight32(status) > 1) { + void __iomem *rcc_addr = + cxlds->regs.ras + CXL_RAS_CAP_CONTROL_OFFSET; + + fe = BIT(FIELD_GET(CXL_RAS_CAP_CONTROL_FE_MASK, + readl(rcc_addr))); + } else { + fe = status; + } + + header_log_copy(cxlds, hl); + trace_cxl_aer_uncorrectable_error(dev, status, fe, hl); + writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr); + + return true; +} + +static pci_ers_result_t cxl_error_detected(struct pci_dev *pdev, + pci_channel_state_t state) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &cxlmd->dev; + bool ue; + + /* + * A frozen channel indicates an impending reset which is fatal to + * CXL.mem operation, and will likely crash the system. On the off + * chance the situation is recoverable dump the status of the RAS + * capability registers and bounce the active state of the memdev. + */ + ue = cxl_report_and_clear(cxlds); + + switch (state) { + case pci_channel_io_normal: + if (ue) { + device_release_driver(dev); + return PCI_ERS_RESULT_NEED_RESET; + } + return PCI_ERS_RESULT_CAN_RECOVER; + case pci_channel_io_frozen: + dev_warn(&pdev->dev, + "%s: frozen state error detected, disable CXL.mem\n", + dev_name(dev)); + device_release_driver(dev); + return PCI_ERS_RESULT_NEED_RESET; + case pci_channel_io_perm_failure: + dev_warn(&pdev->dev, + "failure state error detected, request disconnect\n"); + return PCI_ERS_RESULT_DISCONNECT; + } + return PCI_ERS_RESULT_NEED_RESET; +} + +static pci_ers_result_t cxl_slot_reset(struct pci_dev *pdev) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &cxlmd->dev; + + dev_info(&pdev->dev, "%s: restart CXL.mem after slot reset\n", + dev_name(dev)); + pci_restore_state(pdev); + if (device_attach(dev) <= 0) + return PCI_ERS_RESULT_DISCONNECT; + return PCI_ERS_RESULT_RECOVERED; +} + +static void cxl_error_resume(struct pci_dev *pdev) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &cxlmd->dev; + + dev_info(&pdev->dev, "%s: error resume %s\n", dev_name(dev), + dev->driver ? "successful" : "failed"); +} + +static void cxl_cor_error_detected(struct pci_dev *pdev) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct cxl_memdev *cxlmd = cxlds->cxlmd; + struct device *dev = &cxlmd->dev; + void __iomem *addr; + u32 status; + + if (!cxlds->regs.ras) + return; + + addr = cxlds->regs.ras + CXL_RAS_CORRECTABLE_STATUS_OFFSET; + status = readl(addr); + if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) { + writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr); + trace_cxl_aer_correctable_error(dev, status); + } +} + +static const struct pci_error_handlers cxl_error_handlers = { + .error_detected = cxl_error_detected, + .slot_reset = cxl_slot_reset, + .resume = cxl_error_resume, + .cor_error_detected = cxl_cor_error_detected, +}; + +static struct pci_driver cxl_pci_driver = { + .name = KBUILD_MODNAME, + .id_table = cxl_mem_pci_tbl, + .probe = cxl_pci_probe, + .err_handler = &cxl_error_handlers, + .driver = { + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, +}; + +MODULE_LICENSE("GPL v2"); +module_pci_driver(cxl_pci_driver); +MODULE_IMPORT_NS(CXL); -- cgit v1.2.3