PCI: Add TLP Processing Hints (TPH) support

Add support for PCIe TLP Processing Hints (TPH) support (see PCIe r6.2,
sec 6.17).

Add TPH register definitions in pci_regs.h, including the TPH Requester
capability register, TPH Requester control register, TPH Completer
capability, and the ST fields of MSI-X entry.

Introduce pcie_enable_tph() and pcie_disable_tph(), enabling drivers to
toggle TPH support and configure specific ST mode as needed. Also add a new
kernel parameter, "pci=notph", allowing users to disable TPH support across
the entire system.

Link: https://lore.kernel.org/r/[email protected]
Co-developed-by: Jing Liu <[email protected]>
Co-developed-by: Paul Luse <[email protected]>
Co-developed-by: Eric Van Tassell <[email protected]>
Signed-off-by: Jing Liu <[email protected]>
Signed-off-by: Paul Luse <[email protected]>
Signed-off-by: Eric Van Tassell <[email protected]>
Signed-off-by: Wei Huang <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Ajit Khaparde <[email protected]>
Reviewed-by: Somnath Kotur <[email protected]>
Reviewed-by: Andy Gospodarek <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Reviewed-by: Lukas Wunner <[email protected]>

0 files changed, 0 insertions, 0 deletions