diff options
| author | Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> | 2020-03-23 17:26:05 -0700 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2020-03-28 13:19:02 -0500 |
| commit | 20e15e673b05a045fdbe534d40edf948e1b0b1af (patch) | |
| tree | f400e1e8cffd7ad9e05efbcdba8eba051266c572 | |
| parent | 27005618178ef9e9bf9c42fd91101771c92e9308 (diff) | |
PCI/AER: Add pci_aer_raw_clear_status() to unconditionally clear Error Status
Per the SFI _OSC and DPC Updates ECN [1] implementation note flowchart, the
OS seems to be expected to clear AER status even if it doesn't have
ownership of the AER capability. Unlike the DPC capability, where a DPC
ECN [2] specifies a window when the OS is allowed to access DPC registers
even if it doesn't have ownership, there is no clear model for AER.
Add pci_aer_raw_clear_status() to clear the AER error status registers
unconditionally. This is intended for use only by the EDR path (see [2]).
[1] System Firmware Intermediary (SFI) _OSC and DPC Updates ECN, Feb 24,
2020, affecting PCI Firmware Specification, Rev. 3.2
https://members.pcisig.com/wg/PCI-SIG/document/14076
[2] 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: changelog]
Link: https://lore.kernel.org/r/c19ad28f3633cce67448609e89a75635da0da07d.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>
| -rw-r--r-- | drivers/pci/pci.h | 2 | ||||
| -rw-r--r-- | drivers/pci/pcie/aer.c | 22 |
2 files changed, 20 insertions, 4 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index e48677a0ba42..6d09bb22b73d 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -654,12 +654,14 @@ void pci_aer_exit(struct pci_dev *dev); extern const struct attribute_group aer_stats_attr_group; void pci_aer_clear_fatal_status(struct pci_dev *dev); void pci_aer_clear_device_status(struct pci_dev *dev); +int pci_aer_raw_clear_status(struct pci_dev *dev); #else static inline void pci_no_aer(void) { } static inline void pci_aer_init(struct pci_dev *d) { } static inline void pci_aer_exit(struct pci_dev *d) { } static inline void pci_aer_clear_fatal_status(struct pci_dev *dev) { } static inline void pci_aer_clear_device_status(struct pci_dev *dev) { } +static inline int pci_aer_raw_clear_status(struct pci_dev *dev) { return -EINVAL; } #endif #ifdef CONFIG_ACPI diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index c0540c3761dc..bd9f122165e0 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -420,7 +420,16 @@ void pci_aer_clear_fatal_status(struct pci_dev *dev) pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status); } -int pci_cleanup_aer_error_status_regs(struct pci_dev *dev) +/** + * pci_aer_raw_clear_status - Clear AER error registers. + * @dev: the PCI device + * + * Clearing AER error status registers unconditionally, regardless of + * whether they're owned by firmware or the OS. + * + * Returns 0 on success, or negative on failure. + */ +int pci_aer_raw_clear_status(struct pci_dev *dev) { int pos; u32 status; @@ -433,9 +442,6 @@ int pci_cleanup_aer_error_status_regs(struct pci_dev *dev) if (!pos) return -EIO; - if (pcie_aer_get_firmware_first(dev)) - return -EIO; - port_type = pci_pcie_type(dev); if (port_type == PCI_EXP_TYPE_ROOT_PORT) { pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status); @@ -451,6 +457,14 @@ int pci_cleanup_aer_error_status_regs(struct pci_dev *dev) return 0; } +int pci_cleanup_aer_error_status_regs(struct pci_dev *dev) +{ + if (pcie_aer_get_firmware_first(dev)) + return -EIO; + + return pci_aer_raw_clear_status(dev); +} + void pci_save_aer_state(struct pci_dev *dev) { struct pci_cap_saved_state *save_state; |