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-rw-r--r--drivers/cxl/pci.c973
1 files changed, 973 insertions, 0 deletions
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
new file mode 100644
index 000000000..8bece1e2e
--- /dev/null
+++ b/drivers/cxl/pci.c
@@ -0,0 +1,973 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/moduleparam.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sizes.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/aer.h>
+#include <linux/io.h>
+#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" : "")
+
+struct cxl_dev_id {
+ struct cxl_dev_state *cxlds;
+};
+
+static int cxl_request_irq(struct cxl_dev_state *cxlds, int irq,
+ irq_handler_t handler, irq_handler_t thread_fn)
+{
+ struct device *dev = cxlds->dev;
+ struct cxl_dev_id *dev_id;
+
+ /* dev_id must be globally unique and must contain the cxlds */
+ 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, handler, 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_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(&mds->mbox_mutex);
+ if (mds->security.sanitize_node)
+ mod_delayed_work(system_wq, &mds->security.poll_dwork, 0);
+ mutex_unlock(&mds->mbox_mutex);
+ } else {
+ /* short-circuit the wait in __cxl_pci_mbox_send_cmd() */
+ rcuwait_wake_up(&mds->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;
+
+ mutex_lock(&mds->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(&mds->mbox_mutex);
+}
+
+/**
+ * __cxl_pci_mbox_send_cmd() - Execute a mailbox command
+ * @mds: The memory device driver data
+ * @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_memdev_state *mds,
+ struct cxl_mbox_cmd *mbox_cmd)
+{
+ struct cxl_dev_state *cxlds = &mds->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(&mds->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(&mds->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, mds->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_memdev_state *mds,
+ struct cxl_mbox_cmd *cmd)
+{
+ int rc;
+
+ mutex_lock_io(&mds->mbox_mutex);
+ rc = __cxl_pci_mbox_send_cmd(mds, cmd);
+ mutex_unlock(&mds->mbox_mutex);
+
+ return rc;
+}
+
+static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds)
+{
+ struct cxl_dev_state *cxlds = &mds->cxlds;
+ 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;
+ }
+
+ mds->mbox_send = cxl_pci_mbox_send;
+ mds->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.
+ */
+ mds->payload_size = min_t(size_t, mds->payload_size, SZ_1M);
+ if (mds->payload_size < 256) {
+ dev_err(dev, "Mailbox is too small (%zub)",
+ mds->payload_size);
+ return -ENXIO;
+ }
+
+ dev_dbg(dev, "Mailbox payload sized %zu", mds->payload_size);
+
+ rcuwait_init(&mds->mbox_wait);
+ INIT_DELAYED_WORK(&mds->security.poll_dwork, cxl_mbox_sanitize_work);
+
+ /* background command interrupts are optional */
+ if (!(cap & CXLDEV_MBOX_CAP_BG_CMD_IRQ))
+ 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, NULL, 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_port *port;
+ struct cxl_dport *dport;
+ resource_size_t component_reg_phys;
+
+ *map = (struct cxl_register_map) {
+ .host = &pdev->dev,
+ .resource = CXL_RESOURCE_NONE,
+ };
+
+ port = cxl_pci_find_port(pdev, &dport);
+ if (!port)
+ return -EPROBE_DEFER;
+
+ component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport);
+
+ put_device(&port->dev);
+
+ 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))
+ rc = cxl_rcrb_get_comp_regs(pdev, map);
+
+ 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_get_event_payload *buf;
+
+ buf = kvmalloc(mds->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 int 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 -ENXIO;
+ }
+ return 0;
+}
+
+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, NULL, cxl_event_thread);
+}
+
+static int cxl_event_get_int_policy(struct cxl_memdev_state *mds,
+ struct cxl_event_interrupt_policy *policy)
+{
+ 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(mds, &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_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(mds, &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)
+{
+ 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;
+
+ rc = cxl_mem_alloc_event_buf(mds);
+ if (rc)
+ return rc;
+
+ 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_event_irqsetup(mds);
+ if (rc)
+ return rc;
+
+ cxl_mem_get_event_records(mds, CXLDEV_EVENT_STATUS_ALL);
+
+ return 0;
+}
+
+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;
+
+ /*
+ * 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_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_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.
+ */
+ cxlds->component_reg_phys = CXL_RESOURCE_NONE;
+ rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &map);
+ if (rc)
+ dev_warn(&pdev->dev, "No component registers (%d)\n", rc);
+ else if (!map.component_map.ras.valid)
+ dev_dbg(&pdev->dev, "RAS registers not found\n");
+
+ cxlds->component_reg_phys = map.resource;
+
+ rc = cxl_map_component_regs(&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_await_media_ready(cxlds);
+ if (rc == 0)
+ cxlds->media_ready = true;
+ else
+ dev_warn(&pdev->dev, "Media not active (%d)\n", rc);
+
+ rc = cxl_alloc_irq_vectors(pdev);
+ if (rc)
+ return rc;
+
+ rc = cxl_pci_setup_mailbox(mds);
+ 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(pdev, &pmu_regs, &map);
+ 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);
+ 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 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);