Re: [PATCH V3 0/2] schemas: pci: bridge: Document PCI L0s & L1 entry delay and N_FTS

Rob Herring
2025-02-19T19:49:25Z

On Sun, Feb 16, 2025 at 07:15:08AM +0530, Krishna Chaitanya Chundru wrote:
> Some controllers and endpoints provide provision to program the entry
> delays of L0s & L1 which will allow the link to enter L0s & L1 more
> aggressively to save power.
>
> Per PCIe r6.0, sec 4.2.5.1, during Link training, a PCIe component
> captures the N_FTS value it receives. Per 4.2.5.6, when
> transitioning the Link from L0s to L0, it must transmit N_FTS Fast
> Training Sequences to enable the receiver to obtain bit and Symbol
> lock.
>
> Components may have device-specific ways to configure N_FTS values
> to advertise during Link training. Define an n-fts array with an
> entry for each supported data rate.
>
> Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
> ---
> changes in v3:-
> - Update the description to specfify about entries of the array (rob)
> changes in v2:-
> - Split N_FTS & L1 and L0s entry delay in two patches (bjorn)
> - Update the commit text, description (bjorn)
>
> Krishna Chaitanya Chundru (2):
> schemas: pci: bridge: Document PCI L0s & L1 entry delay
> schemas: pci: bridge: Document PCIe N_FTS
>
> dtschema/schemas/pci/pci-bus-common.yaml | 12 ++++++++++++
> 1 file changed, 12 insertions(+)

Applied, thanks.

Rob