linux-kernel - [PATCH V3 2/2] schemas: pci: bridge: Document PCIe N

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250216014510.3990613-3-krishna.chundru@oss.qualcomm.com>
Date: Sun, 16 Feb 2025 07:15:10 +0530
From: Krishna Chaitanya Chundru <krishna.chundru@....qualcomm.com>
To: andersson@...nel.org, robh@...nel.org, dmitry.baryshkov@...aro.org,
        manivannan.sadhasivam@...aro.org, krzk@...nel.org, helgaas@...nel.org
Cc: linux-arm-msm@...r.kernel.org, devicetree@...r.kernel.org,
        lpieralisi@...nel.org, kw@...ux.com, conor+dt@...nel.org,
        linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
        devicetree-spec@...r.kernel.org, quic_vbadigan@...cinc.com,
        Krishna Chaitanya Chundru <krishna.chundru@....qualcomm.com>
Subject: [PATCH V3 2/2] schemas: pci: bridge: Document PCIe N_FTS

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@....qualcomm.com>
---
 dtschema/schemas/pci/pci-bus-common.yaml | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/dtschema/schemas/pci/pci-bus-common.yaml b/dtschema/schemas/pci/pci-bus-common.yaml
index a9309af..ca97a00 100644
--- a/dtschema/schemas/pci/pci-bus-common.yaml
+++ b/dtschema/schemas/pci/pci-bus-common.yaml
@@ -128,6 +128,16 @@ 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. Each entry in
+      the array specifies a PCIe data rate
+    $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