Commit graph

8 commits

Author SHA1 Message Date
Bjorn Helgaas
82013ff394 PCI/ERR: Add printk level to pcie_print_tlp_log()
aer_print_error() produces output at a printk level (KERN_ERR/KERN_WARNING/
etc) that depends on the kind of error, and it calls pcie_print_tlp_log(),
which previously always produced output at KERN_ERR.

Add a "level" parameter so aer_print_error() can control the level of the
pcie_print_tlp_log() output to match.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://patch.msgid.link/20250522232339.1525671-14-helgaas@kernel.org
2025-05-23 11:02:03 -05:00
Ilpo Järvinen
7e077e6707 PCI/ERR: Handle TLP Log in Flit mode
Flit mode introduced in PCIe r6.0 alters how the TLP Header Log is
presented through AER and DPC Capability registers. The TLP Prefix Log
Register is not present with Flit mode, and the register becomes an
extension of the TLP Header Log (PCIe r6.1 secs 7.8.4.12 & 7.9.14.13).

Adapt pcie_read_tlp_log() and struct pcie_tlp_log to read and store the
extended TLP Header Log when the Link is in Flit mode. As the Prefix Log
and Extended TLP Header are not present at the same time, a C union can be
used.

Determining whether the error occurred while the Link was in Flit mode is a
bit complicated. In case of AER, the Advanced Error Capabilities and
Control Register directly tells whether the error was logged in Flit mode
or not (PCIe r6.1 sec 7.8.4.7). The DPC Capability (PCIe r6.1 sec 7.9.14),
unfortunately, does not contain the same information.

Unlike AER, the DPC Capability does not provide a way to discern whether
the error was logged in Flit mode (this is confirmed by PCI WG to be an
oversight in the spec). DPC will bring the Link down immediately following
an error, which makes it impossible to acquire the Flit Mode Status
directly from the Link Status 2 register because Flit Mode Status is only
set in certain Link states (PCIe r6.1 sec 7.5.3.20). As a workaround, use
the flit_mode value stored into the struct pci_bus.

Link: https://lore.kernel.org/r/20250207161836.2755-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-02-21 17:31:45 -06:00
Ilpo Järvinen
f68ea779d9 PCI: Add pcie_print_tlp_log() to print TLP Header and Prefix Log
Add pcie_print_tlp_log() to print TLP Header and Prefix Log.  Print End-End
Prefixes only if they are non-zero.

Consolidate the few places which currently print TLP using custom
formatting.

Link: https://lore.kernel.org/r/20250114170840.1633-9-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-01-16 12:05:43 -06:00
Ilpo Järvinen
ad41ddeeac PCI: Add TLP Prefix reading to pcie_read_tlp_log()
pcie_read_tlp_log() handles only 4 Header Log DWORDs but TLP Prefix Log
(PCIe r6.1 secs 7.8.4.12 & 7.9.14.13) may also be present.

Generalize pcie_read_tlp_log() and struct pcie_tlp_log to also handle TLP
Prefix Log. The relevant registers are formatted identically in AER and DPC
Capability, but has these variations:

  a) The offsets of TLP Prefix Log registers vary.

  b) DPC RP PIO TLP Prefix Log register can be < 4 DWORDs.

  c) AER TLP Prefix Log Present (PCIe r6.1 sec 7.8.4.7) can indicate Prefix
     Log is not present.

Therefore callers must pass the offset of the TLP Prefix Log register and
the entire length to pcie_read_tlp_log() to be able to read the correct
number of TLP Prefix DWORDs from the correct offset.

Link: https://lore.kernel.org/r/20250114170840.1633-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
[bhelgaas: squash ternary fix from
https://lore.kernel.org/r/20250116172019.88116-1-colin.i.king@gmail.com]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-01-16 12:04:38 -06:00
Ilpo Järvinen
27d41818b6 PCI: Use unsigned int i in pcie_read_tlp_log()
Loop variable i counting from 0 upwards does not need to be signed so make
it unsigned int.

Link: https://lore.kernel.org/r/20250114170840.1633-6-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2025-01-14 17:47:34 -06:00
Ilpo Järvinen
dbfd51ba4c PCI: Use same names in pcie_read_tlp_log() prototype and definition
pcie_read_tlp_log()'s prototype and function signature diverged due to
changes made while applying.

Make the parameters of pcie_read_tlp_log() named identically.

Link: https://lore.kernel.org/r/20250114170840.1633-5-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
2025-01-14 17:46:36 -06:00
Ilpo Järvinen
ede5d5dbef PCI: Add defines for TLP Header/Prefix log sizes
Add defines for AER and DPC capabilities TLP Header Logging register sizes
(PCIe r6.2, sec 7.8.4 / 7.9.14) and replace literals with them.

Link: https://lore.kernel.org/r/20250114170840.1633-4-ilpo.jarvinen@linux.intel.com
Suggested-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2025-01-14 17:39:04 -06:00
Ilpo Järvinen
a71c59269e PCI: Move TLP Log handling to its own file
TLP Log is a PCIe feature and is processed only by AER and DPC.
Configwise, DPC depends AER being enabled. In lack of better place, the TLP
Log handling code was initially placed into pci.c but it can be easily
placed in a separate file.

Move TLP Log handling code to its own file under pcie/ subdirectory and
include it only when AER is enabled.

Link: https://lore.kernel.org/r/20250114170840.1633-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Yazen Ghannam <yazen.ghannam@amd.com>
2025-01-14 17:38:18 -06:00