linux/drivers/cxl/pci.c
Linus Torvalds f0bae243b2 pci-v6.10-changes
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Merge tag 'pci-v6.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Skip E820 checks for MCFG ECAM regions for new (2016+) machines,
     since there's no requirement to describe them in E820 and some
     platforms require ECAM to work (Bjorn Helgaas)

   - Rename PCI_IRQ_LEGACY to PCI_IRQ_INTX to be more specific (Damien
     Le Moal)

   - Remove last user and pci_enable_device_io() (Heiner Kallweit)

   - Wait for Link Training==0 to avoid possible race (Ilpo Järvinen)

   - Skip waiting for devices that have been disconnected while
     suspended (Ilpo Järvinen)

   - Clear Secondary Status errors after enumeration since Master Aborts
     and Unsupported Request errors are an expected part of enumeration
     (Vidya Sagar)

  MSI:

   - Remove unused IMS (Interrupt Message Store) support (Bjorn Helgaas)

  Error handling:

   - Mask Genesys GL975x SD host controller Replay Timer Timeout
     correctable errors caused by a hardware defect; the errors cause
     interrupts that prevent system suspend (Kai-Heng Feng)

   - Fix EDR-related _DSM support, which previously evaluated revision 5
     but assumed revision 6 behavior (Kuppuswamy Sathyanarayanan)

  ASPM:

   - Simplify link state definitions and mask calculation (Ilpo
     Järvinen)

  Power management:

   - Avoid D3cold for HP Pavilion 17 PC/1972 PCIe Ports, where BIOS
     apparently doesn't know how to put them back in D0 (Mario
     Limonciello)

  CXL:

   - Support resetting CXL devices; special handling required because
     CXL Ports mask Secondary Bus Reset by default (Dave Jiang)

  DOE:

   - Support DOE Discovery Version 2 (Alexey Kardashevskiy)

  Endpoint framework:

   - Set endpoint BAR to be 64-bit if the driver says that's all the
     device supports, in addition to doing so if the size is >2GB
     (Niklas Cassel)

   - Simplify endpoint BAR allocation and setting interfaces (Niklas
     Cassel)

  Cadence PCIe controller driver:

   - Drop DT binding redundant msi-parent and pci-bus.yaml (Krzysztof
     Kozlowski)

  Cadence PCIe endpoint driver:

   - Configure endpoint BARs to be 64-bit based on the BAR type, not the
     BAR value (Niklas Cassel)

  Freescale Layerscape PCIe controller driver:

   - Convert DT binding to YAML (Frank Li)

  MediaTek MT7621 PCIe controller driver:

   - Add DT binding missing 'reg' property for child Root Ports
     (Krzysztof Kozlowski)

   - Fix theoretical string truncation in PHY name (Sergio Paracuellos)

  NVIDIA Tegra194 PCIe controller driver:

   - Return success for endpoint probe instead of falling through to the
     failure path (Vidya Sagar)

  Renesas R-Car PCIe controller driver:

   - Add DT binding missing IOMMU properties (Geert Uytterhoeven)

   - Add DT binding R-Car V4H compatible for host and endpoint mode
     (Yoshihiro Shimoda)

  Rockchip PCIe controller driver:

   - Configure endpoint BARs to be 64-bit based on the BAR type, not the
     BAR value (Niklas Cassel)

   - Add DT binding missing maxItems to ep-gpios (Krzysztof Kozlowski)

   - Set the Subsystem Vendor ID, which was previously zero because it
     was masked incorrectly (Rick Wertenbroek)

  Synopsys DesignWare PCIe controller driver:

   - Restructure DBI register access to accommodate devices where this
     requires Refclk to be active (Manivannan Sadhasivam)

   - Remove the deinit() callback, which was only need by the
     pcie-rcar-gen4, and do it directly in that driver (Manivannan
     Sadhasivam)

   - Add dw_pcie_ep_cleanup() so drivers that support PERST# can clean
     up things like eDMA (Manivannan Sadhasivam)

   - Rename dw_pcie_ep_exit() to dw_pcie_ep_deinit() to make it parallel
     to dw_pcie_ep_init() (Manivannan Sadhasivam)

   - Rename dw_pcie_ep_init_complete() to dw_pcie_ep_init_registers() to
     reflect the actual functionality (Manivannan Sadhasivam)

   - Call dw_pcie_ep_init_registers() directly from all the glue
     drivers, not just those that require active Refclk from the host
     (Manivannan Sadhasivam)

   - Remove the "core_init_notifier" flag, which was an obscure way for
     glue drivers to indicate that they depend on Refclk from the host
     (Manivannan Sadhasivam)

  TI J721E PCIe driver:

   - Add DT binding J784S4 SoC Device ID (Siddharth Vadapalli)

   - Add DT binding J722S SoC support (Siddharth Vadapalli)

  TI Keystone PCIe controller driver:

   - Add DT binding missing num-viewport, phys and phy-name properties
     (Jan Kiszka)

  Miscellaneous:

   - Constify and annotate with __ro_after_init (Heiner Kallweit)

   - Convert DT bindings to YAML (Krzysztof Kozlowski)

   - Check for kcalloc() failure in of_pci_prop_intr_map() (Duoming
     Zhou)"

* tag 'pci-v6.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (97 commits)
  PCI: Do not wait for disconnected devices when resuming
  x86/pci: Skip early E820 check for ECAM region
  PCI: Remove unused pci_enable_device_io()
  ata: pata_cs5520: Remove unnecessary call to pci_enable_device_io()
  PCI: Update pci_find_capability() stub return types
  PCI: Remove PCI_IRQ_LEGACY
  scsi: vmw_pvscsi: Do not use PCI_IRQ_LEGACY instead of PCI_IRQ_LEGACY
  scsi: pmcraid: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  scsi: mpt3sas: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  scsi: megaraid_sas: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  scsi: ipr: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  scsi: hpsa: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  scsi: arcmsr: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  wifi: rtw89: Use PCI_IRQ_INTX instead of PCI_IRQ_LEGACY
  dt-bindings: PCI: rockchip,rk3399-pcie: Add missing maxItems to ep-gpios
  Revert "genirq/msi: Provide constants for PCI/IMS support"
  Revert "x86/apic/msi: Enable PCI/IMS"
  Revert "iommu/vt-d: Enable PCI/IMS"
  Revert "iommu/amd: Enable PCI/IMS"
  Revert "PCI/MSI: Provide IMS (Interrupt Message Store) support"
  ...
2024-05-21 10:09:28 -07:00

1071 lines
29 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright(c) 2020 Intel Corporation. All rights reserved. */
#include <asm-generic/unaligned.h>
#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" : "")
/*
* 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_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, bool irq_avail)
{
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) || !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_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 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_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, 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_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;
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_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,
.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_LICENSE("GPL v2");
MODULE_IMPORT_NS(CXL);