[PATCH V2 2/2] schemas: pci: bridge: Document PCIe N_FTS
From: Krishna Chaitanya Chundru
Date: Fri Jan 24 2025 - 05:11:21 EST
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@xxxxxxxxxxxxxxxx>
---
dtschema/schemas/pci/pci-bus-common.yaml | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/dtschema/schemas/pci/pci-bus-common.yaml b/dtschema/schemas/pci/pci-bus-common.yaml
index a9309af..968df43 100644
--- a/dtschema/schemas/pci/pci-bus-common.yaml
+++ b/dtschema/schemas/pci/pci-bus-common.yaml
@@ -128,6 +128,15 @@ properties:
$ref: /schemas/types.yaml#/definitions/uint32
enum: [ 1, 2, 4, 8, 16, 32 ]
+ n-fts:
+ description:
+ The number of Fast Training Sequences (N_FTS) required by the
+ Receiver (this component) when transitioning the Link from L0s
+ to L0; advertised during initial Link training
+ $ref: /schemas/types.yaml#/definitions/uint8-array
+ minItems: 1
+ maxItems: 5
+
reset-gpios:
description: GPIO controlled connection to PERST# signal
maxItems: 1
--
2.34.1