linux/drivers/pci/pcie
Rajat Jain 4353594eb0 PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum
Some devices have an erratum such that they only support DWORD accesses to
some registers.  E.g., this Bayhub O2 device ([VID:DID] = [0x1217:0x8621])
only supports DWORD accesses to LTR latency registers and L1 PM substates
control registers:

  https://github.com/rajatxjain/public_shared/blob/main/OZ711LV2_appnote.pdf

The L1 PM substate control registers are DWORD sized, and hence their
access in the kernel is already DWORD sized, so we don't need to do
anything for them.

However, the LTR registers being WORD sized, are in need of a solution.
Convert the WORD sized accesses to these registers into DWORD sized
accesses while saving and restoring them.

Link: https://lore.kernel.org/r/20211222012105.3438916-1-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-01-11 10:41:24 -06:00
..
aer_inject.c PCI/AER: Add RCEC AER error injection support 2020-12-05 15:26:02 -06:00
aer.c PCI: Correct misspelled and remove duplicated words 2021-10-08 17:14:04 -05:00
aspm.c PCI: Use DWORD accesses for LTR, L1 SS to avoid erratum 2022-01-11 10:41:24 -06:00
dpc.c PCI: pciehp: Ignore Link Down/Up caused by DPC 2021-06-16 17:16:57 -05:00
edr.c PCI/EDR: Log only ACPI_NOTIFY_DISCONNECT_RECOVER events 2020-04-24 18:33:29 -05:00
err.c Revert "PCI: Use to_pci_driver() instead of pci_dev->driver" 2021-11-11 13:36:22 -06:00
Kconfig PCI/LINK: Remove bandwidth notification 2021-02-02 14:25:11 -06:00
Makefile PCI/ERR: Reduce compile time for CONFIG_PCIEAER=n 2021-10-16 09:16:59 -05:00
pme.c PCI: Fix kernel-doc errors 2021-03-11 17:37:20 -06:00
portdrv_core.c Merge branch 'pci/portdrv' 2021-11-05 11:28:45 -05:00
portdrv_pci.c PCI/portdrv: Remove unused resume err_handler 2021-10-15 14:25:08 -05:00
portdrv.h PCI/portdrv: Remove unused pcie_port_bus_{,un}register() declarations 2021-10-15 14:25:18 -05:00
ptm.c pci-v5.15-changes 2021-09-07 19:13:42 -07:00
rcec.c PCI/RCEC: Fix RCiEP device to RCEC association 2021-03-10 15:10:46 -06:00