[PATCH 0/5] cxl: Log downport PCIe AER and CXL RAS error information

From: Terry Bowman
Date: Fri Oct 21 2022 - 14:56:29 EST


This patchset adds CXL downport PCI AER and CXL RAS logging to the CXL
error handling. This is necessary for communicating CXL HW issues to users.
The included patches find and cache pointers to the AER and CXL RAS PCIe
capability structures. The cached pointers are then used to display the
error information in a later patch. These changes follow the CXL
specification, Chapter 8 'Control and Status Registers'.[1]

The first patch enables CXL1.1 RCD support through the ACPI _OSC support
method.

The 2nd and 3rd patches find and map PCIe AER and CXL RAS capabilities.

The 4th patch enables AER error reporting.

The 5th patch adds functionality to log the PCIe AER and RAS capabilities.

TODO work remains to consolidate the HDM and CXL RAS register mapping
(patch#3). The current CXL RAS register mapping will be replaced to reuse
cxl_probe_component_regs() function as David Jiang and Alison Schofield
upstreamed. Should the same be done for the AER registers (patch#2)? The
AER registers are not in the component register block but are instead in
the downport and upport (RCRB).

TODO work remains to add support for upports in some cases here where
downport is addressed. For instance, will need another aer_map to support
upport AER ?

TODO work to support CXL2.0. Should be trivial since aer_cap and aer_stats
is member of 'struct pci_dev'.

Base is from: https://patchwork.kernel.org/project/cxl/list/?series=686272

[1] - https://www.computeexpresslink.org/spec-landing

Terry Bowman (5):
cxl/acpi: Set ACPI's CXL _OSC to indicate CXL1.1 support
cxl/pci: Discover and cache pointer to RCD dport's PCIe AER capability
cxl/pci: Discover and cache pointer to RCD dport's CXL RAS registers
cxl/pci: Enable RCD dport AER reporting
cxl/pci: Log CXL device's PCIe AER and CXL RAS error information

drivers/acpi/pci_root.c | 1 +
drivers/cxl/acpi.c | 56 +++++++
drivers/cxl/core/regs.c | 1 +
drivers/cxl/cxl.h | 13 ++
drivers/cxl/cxlmem.h | 3 +
drivers/cxl/mem.c | 2 +
drivers/cxl/pci.c | 319 ++++++++++++++++++++++++++++++++++++++++
drivers/pci/pcie/aer.c | 45 +++++-
include/linux/pci.h | 4 +
9 files changed, 443 insertions(+), 1 deletion(-)

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2.34.1