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// 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"
/**
* 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: 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);
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;
}
/*
* 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;
}
/*
* CXL v3.0 6.2.3 Table 6-4
* The table indicates that if PCIe Flit Mode is set, then CXL is in 256B flits
* mode, otherwise it's 68B flits mode.
*/
static bool cxl_pci_flit_256(struct pci_dev *pdev)
{
u16 lnksta2;
pcie_capability_read_word(pdev, PCI_EXP_LNKSTA2, &lnksta2);
return lnksta2 & PCI_EXP_LNKSTA2_FLIT;
}
static int cxl_pci_ras_unmask(struct pci_dev *pdev)
{
struct pci_host_bridge *host_bridge = pci_find_host_bridge(pdev->bus);
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 CXL error control */
if (!host_bridge->native_cxl_error)
return -ENXIO;
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;
if (!cxl_pci_flit_256(pdev))
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 cxlds->event_log_lock.
*/
static int cxl_mem_alloc_event_buf(struct cxl_dev_state *cxlds)
{
struct cxl_get_event_payload *buf;
buf = kvmalloc(cxlds->payload_size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
cxlds->event.buf = buf;
return devm_add_action_or_reset(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;
}
struct cxl_dev_id {
struct cxl_dev_state *cxlds;
};
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;
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(cxlds, status);
cond_resched();
} while (status);
return IRQ_HANDLED;
}
static int cxl_event_req_irq(struct cxl_dev_state *cxlds, u8 setting)
{
struct device *dev = cxlds->dev;
struct pci_dev *pdev = to_pci_dev(dev);
struct cxl_dev_id *dev_id;
int irq;
if (FIELD_GET(CXLDEV_EVENT_INT_MODE_MASK, setting) != CXL_INT_MSI_MSIX)
return -ENXIO;
/* 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;
irq = pci_irq_vector(pdev,
FIELD_GET(CXLDEV_EVENT_INT_MSGNUM_MASK, setting));
if (irq < 0)
return irq;
return devm_request_threaded_irq(dev, irq, NULL, cxl_event_thread,
IRQF_SHARED | IRQF_ONESHOT, NULL,
dev_id);
}
static int cxl_event_get_int_policy(struct cxl_dev_state *cxlds,
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(cxlds, &mbox_cmd);
if (rc < 0)
dev_err(cxlds->dev, "Failed to get event interrupt policy : %d",
rc);
return rc;
}
static int cxl_event_config_msgnums(struct cxl_dev_state *cxlds,
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(cxlds, &mbox_cmd);
if (rc < 0) {
dev_err(cxlds->dev, "Failed to set event interrupt policy : %d",
rc);
return rc;
}
/* Retrieve final interrupt settings */
return cxl_event_get_int_policy(cxlds, policy);
}
static int cxl_event_irqsetup(struct cxl_dev_state *cxlds)
{
struct cxl_event_interrupt_policy policy;
int rc;
rc = cxl_event_config_msgnums(cxlds, &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_dev_state *cxlds)
{
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(cxlds);
if (rc)
return rc;
rc = cxl_event_get_int_policy(cxlds, &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(cxlds->dev, "FW still in control of Event Logs despite _OSC settings\n");
return -EBUSY;
}
rc = cxl_event_irqsetup(cxlds);
if (rc)
return rc;
cxl_mem_get_event_records(cxlds, 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_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;
pci_set_master(pdev);
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;
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_await_media_ready(cxlds);
if (rc == 0)
cxlds->media_ready = true;
else
dev_warn(&pdev->dev, "Media not active (%d)\n", rc);
rc = cxl_pci_setup_mailbox(cxlds);
if (rc)
return rc;
rc = cxl_enumerate_cmds(cxlds);
if (rc)
return rc;
rc = cxl_set_timestamp(cxlds);
if (rc)
return rc;
rc = cxl_poison_state_init(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;
rc = cxl_alloc_irq_vectors(pdev);
if (rc)
return rc;
cxlmd = devm_cxl_add_memdev(cxlds);
if (IS_ERR(cxlmd))
return PTR_ERR(cxlmd);
rc = cxl_event_config(host_bridge, cxlds);
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);
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