linux_dsm_epyc7002/include/linux/pci-acpi.h
Kuppuswamy Sathyanarayanan ac1c8e35a3 PCI/DPC: Add Error Disconnect Recover (EDR) support
Error Disconnect Recover (EDR) is a feature that allows ACPI firmware to
notify OSPM that a device has been disconnected due to an error condition
(ACPI v6.3, sec 5.6.6).  OSPM advertises its support for EDR on PCI devices
via _OSC (see [1], sec 4.5.1, table 4-4).  The OSPM EDR notify handler
should invalidate software state associated with disconnected devices and
may attempt to recover them.  OSPM communicates the status of recovery to
the firmware via _OST (sec 6.3.5.2).

For PCIe, firmware may use Downstream Port Containment (DPC) to support
EDR.  Per [1], sec 4.5.1, table 4-6, even if firmware has retained control
of DPC, OSPM may read/write DPC control and status registers during the EDR
notification processing window, i.e., from the time it receives an EDR
notification until it clears the DPC Trigger Status.

Note that per [1], sec 4.5.1 and 4.5.2.4,

  1. If the OS supports EDR, it should advertise that to firmware by
     setting OSC_PCI_EDR_SUPPORT in _OSC Support.

  2. If the OS sets OSC_PCI_EXPRESS_DPC_CONTROL in _OSC Control to request
     control of the DPC capability, it must also set OSC_PCI_EDR_SUPPORT in
     _OSC Support.

Add an EDR notify handler to attempt recovery.

[1] Downstream Port Containment Related Enhancements ECN, Jan 28, 2019,
    affecting PCI Firmware Specification, Rev. 3.2
    https://members.pcisig.com/wg/PCI-SIG/document/12888

[bhelgaas: squash add/enable patches into one]
Link: https://lore.kernel.org/r/90f91fe6d25c13f9d2255d2ce97ca15be307e1bb.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
2020-03-28 13:19:04 -05:00

135 lines
3.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* File pci-acpi.h
*
* Copyright (C) 2004 Intel
* Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
*/
#ifndef _PCI_ACPI_H_
#define _PCI_ACPI_H_
#include <linux/acpi.h>
#ifdef CONFIG_ACPI
extern acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev);
static inline acpi_status pci_acpi_remove_bus_pm_notifier(struct acpi_device *dev)
{
return acpi_remove_pm_notifier(dev);
}
extern acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
struct pci_dev *pci_dev);
static inline acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
{
return acpi_remove_pm_notifier(dev);
}
extern phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle);
struct pci_ecam_ops;
extern int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres,
struct pci_ecam_ops **ecam_ops);
static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
{
struct pci_bus *pbus = pdev->bus;
/* Find a PCI root bus */
while (!pci_is_root_bus(pbus))
pbus = pbus->parent;
return ACPI_HANDLE(pbus->bridge);
}
static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus)
{
struct device *dev;
if (pci_is_root_bus(pbus))
dev = pbus->bridge;
else {
/* If pbus is a virtual bus, there is no bridge to it */
if (!pbus->self)
return NULL;
dev = &pbus->self->dev;
}
return ACPI_HANDLE(dev);
}
struct acpi_pci_root;
struct acpi_pci_root_ops;
struct acpi_pci_root_info {
struct acpi_pci_root *root;
struct acpi_device *bridge;
struct acpi_pci_root_ops *ops;
struct list_head resources;
char name[16];
};
struct acpi_pci_root_ops {
struct pci_ops *pci_ops;
int (*init_info)(struct acpi_pci_root_info *info);
void (*release_info)(struct acpi_pci_root_info *info);
int (*prepare_resources)(struct acpi_pci_root_info *info);
};
extern int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info);
extern struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
struct acpi_pci_root_ops *ops,
struct acpi_pci_root_info *info,
void *sd);
void acpi_pci_add_bus(struct pci_bus *bus);
void acpi_pci_remove_bus(struct pci_bus *bus);
#ifdef CONFIG_ACPI_PCI_SLOT
void acpi_pci_slot_init(void);
void acpi_pci_slot_enumerate(struct pci_bus *bus);
void acpi_pci_slot_remove(struct pci_bus *bus);
#else
static inline void acpi_pci_slot_init(void) { }
static inline void acpi_pci_slot_enumerate(struct pci_bus *bus) { }
static inline void acpi_pci_slot_remove(struct pci_bus *bus) { }
#endif
#ifdef CONFIG_HOTPLUG_PCI_ACPI
void acpiphp_init(void);
void acpiphp_enumerate_slots(struct pci_bus *bus);
void acpiphp_remove_slots(struct pci_bus *bus);
void acpiphp_check_host_bridge(struct acpi_device *adev);
#else
static inline void acpiphp_init(void) { }
static inline void acpiphp_enumerate_slots(struct pci_bus *bus) { }
static inline void acpiphp_remove_slots(struct pci_bus *bus) { }
static inline void acpiphp_check_host_bridge(struct acpi_device *adev) { }
#endif
extern const guid_t pci_acpi_dsm_guid;
#define IGNORE_PCI_BOOT_CONFIG_DSM 0x05
#define DEVICE_LABEL_DSM 0x07
#define RESET_DELAY_DSM 0x08
#define FUNCTION_DELAY_DSM 0x09
#ifdef CONFIG_PCIE_EDR
void pci_acpi_add_edr_notifier(struct pci_dev *pdev);
void pci_acpi_remove_edr_notifier(struct pci_dev *pdev);
#else
static inline void pci_acpi_add_edr_notifier(struct pci_dev *pdev) { }
static inline void pci_acpi_remove_edr_notifier(struct pci_dev *pdev) { }
#endif /* CONFIG_PCIE_EDR */
#else /* CONFIG_ACPI */
static inline void acpi_pci_add_bus(struct pci_bus *bus) { }
static inline void acpi_pci_remove_bus(struct pci_bus *bus) { }
#endif /* CONFIG_ACPI */
#ifdef CONFIG_ACPI_APEI
extern bool aer_acpi_firmware_first(void);
#else
static inline bool aer_acpi_firmware_first(void) { return false; }
#endif
#endif /* _PCI_ACPI_H_ */