// 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 #include "cxlmem.h" #include "cxlpci.h" #include "cxl.h" #include "pmu.h" /** * 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" : "") /* * Threaded irq dev_id's must be globally unique. cxl_dev_id provides a unique * wrapper object for each irq within the same cxlds. */ struct cxl_dev_id { struct cxl_dev_state *cxlds; }; static int cxl_request_irq(struct cxl_dev_state *cxlds, int irq, irq_handler_t thread_fn) { struct device *dev = cxlds->dev; struct cxl_dev_id *dev_id; dev_id = devm_kzalloc(dev, sizeof(*dev_id), GFP_KERNEL); if (!dev_id) return -ENOMEM; dev_id->cxlds = cxlds; return devm_request_threaded_irq(dev, irq, NULL, thread_fn, IRQF_SHARED | IRQF_ONESHOT, NULL, dev_id); } static bool cxl_mbox_background_complete(struct cxl_dev_state *cxlds) { u64 reg; reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_BG_CMD_STATUS_OFFSET); return FIELD_GET(CXLDEV_MBOX_BG_CMD_COMMAND_PCT_MASK, reg) == 100; } static irqreturn_t cxl_pci_mbox_irq(int irq, void *id) { u64 reg; u16 opcode; struct cxl_dev_id *dev_id = id; struct cxl_dev_state *cxlds = dev_id->cxlds; struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox; struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); if (!cxl_mbox_background_complete(cxlds)) return IRQ_NONE; reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_BG_CMD_STATUS_OFFSET); opcode = FIELD_GET(CXLDEV_MBOX_BG_CMD_COMMAND_OPCODE_MASK, reg); if (opcode == CXL_MBOX_OP_SANITIZE) { mutex_lock(&cxl_mbox->mbox_mutex); if (mds->security.sanitize_node) mod_delayed_work(system_wq, &mds->security.poll_dwork, 0); mutex_unlock(&cxl_mbox->mbox_mutex); } else { /* short-circuit the wait in __cxl_pci_mbox_send_cmd() */ rcuwait_wake_up(&cxl_mbox->mbox_wait); } return IRQ_HANDLED; } /* * Sanitization operation polling mode. */ static void cxl_mbox_sanitize_work(struct work_struct *work) { struct cxl_memdev_state *mds = container_of(work, typeof(*mds), security.poll_dwork.work); struct cxl_dev_state *cxlds = &mds->cxlds; struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox; mutex_lock(&cxl_mbox->mbox_mutex); if (cxl_mbox_background_complete(cxlds)) { mds->security.poll_tmo_secs = 0; if (mds->security.sanitize_node) sysfs_notify_dirent(mds->security.sanitize_node); mds->security.sanitize_active = false; dev_dbg(cxlds->dev, "Sanitization operation ended\n"); } else { int timeout = mds->security.poll_tmo_secs + 10; mds->security.poll_tmo_secs = min(15 * 60, timeout); schedule_delayed_work(&mds->security.poll_dwork, timeout * HZ); } mutex_unlock(&cxl_mbox->mbox_mutex); } /** * __cxl_pci_mbox_send_cmd() - Execute a mailbox command * @cxl_mbox: CXL mailbox context * @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_mailbox *cxl_mbox, struct cxl_mbox_cmd *mbox_cmd) { struct cxl_dev_state *cxlds = mbox_to_cxlds(cxl_mbox); struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); 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(&cxl_mbox->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; } /* * With sanitize polling, hardware might be done and the poller still * not be in sync. Ensure no new command comes in until so. Keep the * hardware semantics and only allow device health status. */ if (mds->security.poll_tmo_secs > 0) { if (mbox_cmd->opcode != CXL_MBOX_OP_GET_HEALTH_INFO) 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: 0x%04x\n", mbox_cmd->opcode); 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); /* * Handle the background command in a synchronous manner. * * All other mailbox commands will serialize/queue on the mbox_mutex, * which we currently hold. Furthermore this also guarantees that * cxl_mbox_background_complete() checks are safe amongst each other, * in that no new bg operation can occur in between. * * Background operations are timesliced in accordance with the nature * of the command. In the event of timeout, the mailbox state is * indeterminate until the next successful command submission and the * driver can get back in sync with the hardware state. */ if (mbox_cmd->return_code == CXL_MBOX_CMD_RC_BACKGROUND) { u64 bg_status_reg; int i, timeout; /* * Sanitization is a special case which monopolizes the device * and cannot be timesliced. Handle asynchronously instead, * and allow userspace to poll(2) for completion. */ if (mbox_cmd->opcode == CXL_MBOX_OP_SANITIZE) { if (mds->security.sanitize_active) return -EBUSY; /* give first timeout a second */ timeout = 1; mds->security.poll_tmo_secs = timeout; mds->security.sanitize_active = true; schedule_delayed_work(&mds->security.poll_dwork, timeout * HZ); dev_dbg(dev, "Sanitization operation started\n"); goto success; } dev_dbg(dev, "Mailbox background operation (0x%04x) started\n", mbox_cmd->opcode); timeout = mbox_cmd->poll_interval_ms; for (i = 0; i < mbox_cmd->poll_count; i++) { if (rcuwait_wait_event_timeout(&cxl_mbox->mbox_wait, cxl_mbox_background_complete(cxlds), TASK_UNINTERRUPTIBLE, msecs_to_jiffies(timeout)) > 0) break; } if (!cxl_mbox_background_complete(cxlds)) { dev_err(dev, "timeout waiting for background (%d ms)\n", timeout * mbox_cmd->poll_count); return -ETIMEDOUT; } bg_status_reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_BG_CMD_STATUS_OFFSET); mbox_cmd->return_code = FIELD_GET(CXLDEV_MBOX_BG_CMD_COMMAND_RC_MASK, bg_status_reg); dev_dbg(dev, "Mailbox background operation (0x%04x) completed\n", mbox_cmd->opcode); } 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 */ } success: /* #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; n = min3(mbox_cmd->size_out, cxl_mbox->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_mailbox *cxl_mbox, struct cxl_mbox_cmd *cmd) { int rc; mutex_lock_io(&cxl_mbox->mbox_mutex); rc = __cxl_pci_mbox_send_cmd(cxl_mbox, cmd); mutex_unlock(&cxl_mbox->mbox_mutex); return rc; } static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds, bool irq_avail) { struct cxl_dev_state *cxlds = &mds->cxlds; struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox; const int cap = readl(cxlds->regs.mbox + CXLDEV_MBOX_CAPS_OFFSET); struct device *dev = cxlds->dev; unsigned long timeout; int irq, msgnum; u64 md_status; u32 ctrl; 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(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(dev, md_status, "timeout awaiting mailbox idle"); return -ETIMEDOUT; } cxl_mbox->mbox_send = cxl_pci_mbox_send; cxl_mbox->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. */ cxl_mbox->payload_size = min_t(size_t, cxl_mbox->payload_size, SZ_1M); if (cxl_mbox->payload_size < 256) { dev_err(dev, "Mailbox is too small (%zub)", cxl_mbox->payload_size); return -ENXIO; } dev_dbg(dev, "Mailbox payload sized %zu", cxl_mbox->payload_size); INIT_DELAYED_WORK(&mds->security.poll_dwork, cxl_mbox_sanitize_work); /* background command interrupts are optional */ if (!(cap & CXLDEV_MBOX_CAP_BG_CMD_IRQ) || !irq_avail) return 0; msgnum = FIELD_GET(CXLDEV_MBOX_CAP_IRQ_MSGNUM_MASK, cap); irq = pci_irq_vector(to_pci_dev(cxlds->dev), msgnum); if (irq < 0) return 0; if (cxl_request_irq(cxlds, irq, cxl_pci_mbox_irq)) return 0; dev_dbg(cxlds->dev, "Mailbox interrupts enabled\n"); /* enable background command mbox irq support */ ctrl = readl(cxlds->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET); ctrl |= CXLDEV_MBOX_CTRL_BG_CMD_IRQ; writel(ctrl, cxlds->regs.mbox + CXLDEV_MBOX_CTRL_OFFSET); return 0; } /* * 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 int cxl_rcrb_get_comp_regs(struct pci_dev *pdev, struct cxl_register_map *map, struct cxl_dport *dport) { resource_size_t component_reg_phys; *map = (struct cxl_register_map) { .host = &pdev->dev, .resource = CXL_RESOURCE_NONE, }; struct cxl_port *port __free(put_cxl_port) = cxl_pci_find_port(pdev, &dport); if (!port) return -EPROBE_DEFER; component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport); if (component_reg_phys == CXL_RESOURCE_NONE) return -ENXIO; map->resource = component_reg_phys; map->reg_type = CXL_REGLOC_RBI_COMPONENT; map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE; return 0; } static int cxl_pci_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 the Register Locator DVSEC does not exist, check if it * is an RCH and try to extract the Component Registers from * an RCRB. */ if (rc && type == CXL_REGLOC_RBI_COMPONENT && is_cxl_restricted(pdev)) { struct cxl_dport *dport; struct cxl_port *port __free(put_cxl_port) = cxl_pci_find_port(pdev, &dport); if (!port) return -EPROBE_DEFER; rc = cxl_rcrb_get_comp_regs(pdev, map, dport); if (rc) return rc; rc = cxl_dport_map_rcd_linkcap(pdev, dport); if (rc) return rc; } else if (rc) { return rc; } return cxl_setup_regs(map); } static int cxl_pci_ras_unmask(struct pci_dev *pdev) { struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); void __iomem *addr; u32 orig_val, val, mask; u16 cap; int rc; if (!cxlds->regs.ras) { dev_dbg(&pdev->dev, "No RAS registers.\n"); return 0; } /* BIOS has PCIe AER error control */ if (!pcie_aer_is_native(pdev)) return 0; rc = pcie_capability_read_word(pdev, PCI_EXP_DEVCTL, &cap); if (rc) return rc; if (cap & PCI_EXP_DEVCTL_URRE) { addr = cxlds->regs.ras + CXL_RAS_UNCORRECTABLE_MASK_OFFSET; orig_val = readl(addr); mask = CXL_RAS_UNCORRECTABLE_MASK_MASK | CXL_RAS_UNCORRECTABLE_MASK_F256B_MASK; val = orig_val & ~mask; writel(val, addr); dev_dbg(&pdev->dev, "Uncorrectable RAS Errors Mask: %#x -> %#x\n", orig_val, val); } if (cap & PCI_EXP_DEVCTL_CERE) { addr = cxlds->regs.ras + CXL_RAS_CORRECTABLE_MASK_OFFSET; orig_val = readl(addr); val = orig_val & ~CXL_RAS_CORRECTABLE_MASK_MASK; writel(val, addr); dev_dbg(&pdev->dev, "Correctable RAS Errors Mask: %#x -> %#x\n", orig_val, val); } return 0; } static void free_event_buf(void *buf) { kvfree(buf); } /* * There is a single buffer for reading event logs from the mailbox. All logs * share this buffer protected by the mds->event_log_lock. */ static int cxl_mem_alloc_event_buf(struct cxl_memdev_state *mds) { struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox; struct cxl_get_event_payload *buf; buf = kvmalloc(cxl_mbox->payload_size, GFP_KERNEL); if (!buf) return -ENOMEM; mds->event.buf = buf; return devm_add_action_or_reset(mds->cxlds.dev, free_event_buf, buf); } static bool cxl_alloc_irq_vectors(struct pci_dev *pdev) { int nvecs; /* * Per CXL 3.0 3.1.1 CXL.io Endpoint a function on a CXL device must * not generate INTx messages if that function participates in * CXL.cache or CXL.mem. * * Additionally pci_alloc_irq_vectors() handles calling * pci_free_irq_vectors() automatically despite not being called * pcim_*. See pci_setup_msi_context(). */ nvecs = pci_alloc_irq_vectors(pdev, 1, CXL_PCI_DEFAULT_MAX_VECTORS, PCI_IRQ_MSIX | PCI_IRQ_MSI); if (nvecs < 1) { dev_dbg(&pdev->dev, "Failed to alloc irq vectors: %d\n", nvecs); return false; } return true; } static irqreturn_t cxl_event_thread(int irq, void *id) { struct cxl_dev_id *dev_id = id; struct cxl_dev_state *cxlds = dev_id->cxlds; struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); u32 status; do { /* * CXL 3.0 8.2.8.3.1: The lower 32 bits are the status; * ignore the reserved upper 32 bits */ status = readl(cxlds->regs.status + CXLDEV_DEV_EVENT_STATUS_OFFSET); /* Ignore logs unknown to the driver */ status &= CXLDEV_EVENT_STATUS_ALL; if (!status) break; cxl_mem_get_event_records(mds, status); cond_resched(); } while (status); return IRQ_HANDLED; } static int cxl_event_req_irq(struct cxl_dev_state *cxlds, u8 setting) { struct pci_dev *pdev = to_pci_dev(cxlds->dev); int irq; if (FIELD_GET(CXLDEV_EVENT_INT_MODE_MASK, setting) != CXL_INT_MSI_MSIX) return -ENXIO; irq = pci_irq_vector(pdev, FIELD_GET(CXLDEV_EVENT_INT_MSGNUM_MASK, setting)); if (irq < 0) return irq; return cxl_request_irq(cxlds, irq, cxl_event_thread); } static int cxl_event_get_int_policy(struct cxl_memdev_state *mds, struct cxl_event_interrupt_policy *policy) { struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox; struct cxl_mbox_cmd mbox_cmd = { .opcode = CXL_MBOX_OP_GET_EVT_INT_POLICY, .payload_out = policy, .size_out = sizeof(*policy), }; int rc; rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd); if (rc < 0) dev_err(mds->cxlds.dev, "Failed to get event interrupt policy : %d", rc); return rc; } static int cxl_event_config_msgnums(struct cxl_memdev_state *mds, struct cxl_event_interrupt_policy *policy) { struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox; struct cxl_mbox_cmd mbox_cmd; int rc; *policy = (struct cxl_event_interrupt_policy) { .info_settings = CXL_INT_MSI_MSIX, .warn_settings = CXL_INT_MSI_MSIX, .failure_settings = CXL_INT_MSI_MSIX, .fatal_settings = CXL_INT_MSI_MSIX, }; mbox_cmd = (struct cxl_mbox_cmd) { .opcode = CXL_MBOX_OP_SET_EVT_INT_POLICY, .payload_in = policy, .size_in = sizeof(*policy), }; rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd); if (rc < 0) { dev_err(mds->cxlds.dev, "Failed to set event interrupt policy : %d", rc); return rc; } /* Retrieve final interrupt settings */ return cxl_event_get_int_policy(mds, policy); } static int cxl_event_irqsetup(struct cxl_memdev_state *mds) { struct cxl_dev_state *cxlds = &mds->cxlds; struct cxl_event_interrupt_policy policy; int rc; rc = cxl_event_config_msgnums(mds, &policy); if (rc) return rc; rc = cxl_event_req_irq(cxlds, policy.info_settings); if (rc) { dev_err(cxlds->dev, "Failed to get interrupt for event Info log\n"); return rc; } rc = cxl_event_req_irq(cxlds, policy.warn_settings); if (rc) { dev_err(cxlds->dev, "Failed to get interrupt for event Warn log\n"); return rc; } rc = cxl_event_req_irq(cxlds, policy.failure_settings); if (rc) { dev_err(cxlds->dev, "Failed to get interrupt for event Failure log\n"); return rc; } rc = cxl_event_req_irq(cxlds, policy.fatal_settings); if (rc) { dev_err(cxlds->dev, "Failed to get interrupt for event Fatal log\n"); return rc; } return 0; } static bool cxl_event_int_is_fw(u8 setting) { u8 mode = FIELD_GET(CXLDEV_EVENT_INT_MODE_MASK, setting); return mode == CXL_INT_FW; } static int cxl_event_config(struct pci_host_bridge *host_bridge, struct cxl_memdev_state *mds, bool irq_avail) { struct cxl_event_interrupt_policy policy; int rc; /* * When BIOS maintains CXL error reporting control, it will process * event records. Only one agent can do so. */ if (!host_bridge->native_cxl_error) return 0; if (!irq_avail) { dev_info(mds->cxlds.dev, "No interrupt support, disable event processing.\n"); return 0; } rc = cxl_event_get_int_policy(mds, &policy); if (rc) return rc; if (cxl_event_int_is_fw(policy.info_settings) || cxl_event_int_is_fw(policy.warn_settings) || cxl_event_int_is_fw(policy.failure_settings) || cxl_event_int_is_fw(policy.fatal_settings)) { dev_err(mds->cxlds.dev, "FW still in control of Event Logs despite _OSC settings\n"); return -EBUSY; } rc = cxl_mem_alloc_event_buf(mds); if (rc) return rc; rc = cxl_event_irqsetup(mds); if (rc) return rc; cxl_mem_get_event_records(mds, CXLDEV_EVENT_STATUS_ALL); return 0; } static int cxl_pci_type3_init_mailbox(struct cxl_dev_state *cxlds) { int rc; /* * Fail the init if there's no mailbox. For a type3 this is out of spec. */ if (!cxlds->reg_map.device_map.mbox.valid) return -ENODEV; rc = cxl_mailbox_init(&cxlds->cxl_mbox, cxlds->dev); if (rc) return rc; return 0; } static ssize_t rcd_pcie_cap_emit(struct device *dev, u16 offset, char *buf, size_t width) { struct cxl_dev_state *cxlds = dev_get_drvdata(dev); struct cxl_memdev *cxlmd = cxlds->cxlmd; struct device *root_dev; struct cxl_dport *dport; struct cxl_port *root __free(put_cxl_port) = cxl_mem_find_port(cxlmd, &dport); if (!root) return -ENXIO; root_dev = root->uport_dev; if (!root_dev) return -ENXIO; guard(device)(root_dev); if (!root_dev->driver) return -ENXIO; switch (width) { case 2: return sysfs_emit(buf, "%#x\n", readw(dport->regs.rcd_pcie_cap + offset)); case 4: return sysfs_emit(buf, "%#x\n", readl(dport->regs.rcd_pcie_cap + offset)); default: return -EINVAL; } } static ssize_t rcd_link_cap_show(struct device *dev, struct device_attribute *attr, char *buf) { return rcd_pcie_cap_emit(dev, PCI_EXP_LNKCAP, buf, sizeof(u32)); } static DEVICE_ATTR_RO(rcd_link_cap); static ssize_t rcd_link_ctrl_show(struct device *dev, struct device_attribute *attr, char *buf) { return rcd_pcie_cap_emit(dev, PCI_EXP_LNKCTL, buf, sizeof(u16)); } static DEVICE_ATTR_RO(rcd_link_ctrl); static ssize_t rcd_link_status_show(struct device *dev, struct device_attribute *attr, char *buf) { return rcd_pcie_cap_emit(dev, PCI_EXP_LNKSTA, buf, sizeof(u16)); } static DEVICE_ATTR_RO(rcd_link_status); static struct attribute *cxl_rcd_attrs[] = { &dev_attr_rcd_link_cap.attr, &dev_attr_rcd_link_ctrl.attr, &dev_attr_rcd_link_status.attr, NULL }; static umode_t cxl_rcd_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = kobj_to_dev(kobj); struct pci_dev *pdev = to_pci_dev(dev); if (is_cxl_restricted(pdev)) return a->mode; return 0; } static struct attribute_group cxl_rcd_group = { .attrs = cxl_rcd_attrs, .is_visible = cxl_rcd_visible, }; __ATTRIBUTE_GROUPS(cxl_rcd); static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct pci_host_bridge *host_bridge = pci_find_host_bridge(pdev->bus); struct cxl_memdev_state *mds; struct cxl_dev_state *cxlds; struct cxl_register_map map; struct cxl_memdev *cxlmd; int i, rc, pmu_count; bool irq_avail; /* * 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; pci_set_master(pdev); mds = cxl_memdev_state_create(&pdev->dev); if (IS_ERR(mds)) return PTR_ERR(mds); cxlds = &mds->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_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_pci_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map); if (rc) return rc; rc = cxl_map_device_regs(&map, &cxlds->regs.device_regs); 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. */ rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &cxlds->reg_map); if (rc) dev_warn(&pdev->dev, "No component registers (%d)\n", rc); else if (!cxlds->reg_map.component_map.ras.valid) dev_dbg(&pdev->dev, "RAS registers not found\n"); rc = cxl_map_component_regs(&cxlds->reg_map, &cxlds->regs.component, BIT(CXL_CM_CAP_CAP_ID_RAS)); if (rc) dev_dbg(&pdev->dev, "Failed to map RAS capability.\n"); rc = cxl_pci_type3_init_mailbox(cxlds); if (rc) return rc; rc = cxl_await_media_ready(cxlds); if (rc == 0) cxlds->media_ready = true; else dev_warn(&pdev->dev, "Media not active (%d)\n", rc); irq_avail = cxl_alloc_irq_vectors(pdev); rc = cxl_pci_setup_mailbox(mds, irq_avail); if (rc) return rc; rc = cxl_enumerate_cmds(mds); if (rc) return rc; rc = cxl_set_timestamp(mds); if (rc) return rc; rc = cxl_poison_state_init(mds); if (rc) return rc; rc = cxl_dev_state_identify(mds); if (rc) return rc; rc = cxl_mem_create_range_info(mds); if (rc) return rc; cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlds); if (IS_ERR(cxlmd)) return PTR_ERR(cxlmd); rc = devm_cxl_setup_fw_upload(&pdev->dev, mds); if (rc) return rc; rc = devm_cxl_sanitize_setup_notifier(&pdev->dev, cxlmd); if (rc) return rc; pmu_count = cxl_count_regblock(pdev, CXL_REGLOC_RBI_PMU); for (i = 0; i < pmu_count; i++) { struct cxl_pmu_regs pmu_regs; rc = cxl_find_regblock_instance(pdev, CXL_REGLOC_RBI_PMU, &map, i); if (rc) { dev_dbg(&pdev->dev, "Could not find PMU regblock\n"); break; } rc = cxl_map_pmu_regs(&map, &pmu_regs); if (rc) { dev_dbg(&pdev->dev, "Could not map PMU regs\n"); break; } rc = devm_cxl_pmu_add(cxlds->dev, &pmu_regs, cxlmd->id, i, CXL_PMU_MEMDEV); if (rc) { dev_dbg(&pdev->dev, "Could not add PMU instance\n"); break; } } rc = cxl_event_config(host_bridge, mds, irq_avail); if (rc) return rc; rc = cxl_pci_ras_unmask(pdev); if (rc) dev_dbg(&pdev->dev, "No RAS reporting unmasked\n"); 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); 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_reset_done(struct pci_dev *pdev) { struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); struct cxl_memdev *cxlmd = cxlds->cxlmd; struct device *dev = &pdev->dev; /* * FLR does not expect to touch the HDM decoders and related * registers. SBR, however, will wipe all device configurations. * Issue a warning if there was an active decoder before the reset * that no longer exists. */ guard(device)(&cxlmd->dev); if (cxlmd->endpoint && cxl_endpoint_decoder_reset_detected(cxlmd->endpoint)) { dev_crit(dev, "SBR happened without memory regions removal.\n"); dev_crit(dev, "System may be unstable if regions hosted system memory.\n"); add_taint(TAINT_USER, LOCKDEP_STILL_OK); } } 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, .reset_done = cxl_reset_done, }; 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, .dev_groups = cxl_rcd_groups, .driver = { .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, }; #define CXL_EVENT_HDR_FLAGS_REC_SEVERITY GENMASK(1, 0) static void cxl_handle_cper_event(enum cxl_event_type ev_type, struct cxl_cper_event_rec *rec) { struct cper_cxl_event_devid *device_id = &rec->hdr.device_id; struct pci_dev *pdev __free(pci_dev_put) = NULL; enum cxl_event_log_type log_type; struct cxl_dev_state *cxlds; unsigned int devfn; u32 hdr_flags; pr_debug("CPER event %d for device %u:%u:%u.%u\n", ev_type, device_id->segment_num, device_id->bus_num, device_id->device_num, device_id->func_num); devfn = PCI_DEVFN(device_id->device_num, device_id->func_num); pdev = pci_get_domain_bus_and_slot(device_id->segment_num, device_id->bus_num, devfn); if (!pdev) return; guard(device)(&pdev->dev); if (pdev->driver != &cxl_pci_driver) return; cxlds = pci_get_drvdata(pdev); if (!cxlds) return; /* Fabricate a log type */ hdr_flags = get_unaligned_le24(rec->event.generic.hdr.flags); log_type = FIELD_GET(CXL_EVENT_HDR_FLAGS_REC_SEVERITY, hdr_flags); cxl_event_trace_record(cxlds->cxlmd, log_type, ev_type, &uuid_null, &rec->event); } static void cxl_cper_work_fn(struct work_struct *work) { struct cxl_cper_work_data wd; while (cxl_cper_kfifo_get(&wd)) cxl_handle_cper_event(wd.event_type, &wd.rec); } static DECLARE_WORK(cxl_cper_work, cxl_cper_work_fn); static int __init cxl_pci_driver_init(void) { int rc; rc = pci_register_driver(&cxl_pci_driver); if (rc) return rc; rc = cxl_cper_register_work(&cxl_cper_work); if (rc) pci_unregister_driver(&cxl_pci_driver); return rc; } static void __exit cxl_pci_driver_exit(void) { cxl_cper_unregister_work(&cxl_cper_work); cancel_work_sync(&cxl_cper_work); pci_unregister_driver(&cxl_pci_driver); } module_init(cxl_pci_driver_init); module_exit(cxl_pci_driver_exit); MODULE_DESCRIPTION("CXL: PCI manageability"); MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS("CXL");