Re: [PATCH net-next v6 01/14] dt-bindings: net: Add PPE for Qualcomm IPQ9574 SoC
From: Luo Jie
Date: Wed Jul 23 2025 - 01:01:41 EST
On 7/22/2025 3:35 AM, Rob Herring wrote:
On Sun, Jul 20, 2025 at 06:57:08PM +0800, Luo Jie wrote:
The PPE (packet process engine) hardware block is available in Qualcomm
IPQ chipsets that support PPE architecture, such as IPQ9574. The PPE in
the IPQ9574 SoC includes six ethernet ports (6 GMAC and 6 XGMAC), which
are used to connect with external PHY devices by PCS. It includes an L2
switch function for bridging packets among the 6 ethernet ports and the
CPU port. The CPU port enables packet transfer between the ethernet ports
and the ARM cores in the SoC, using the ethernet DMA.
The PPE also includes packet processing offload capabilities for various
networking functions such as route and bridge flows, VLANs, different
tunnel protocols and VPN.
The PPE switch is modeled according to the ethernet switch schema, with
additional properties defined for the switch node for interrupts, clocks,
resets, interconnects and Ethernet DMA. The switch port node is extended
with additional properties for clocks and resets.
Signed-off-by: Luo Jie <quic_luoj@xxxxxxxxxxx>
---
.../devicetree/bindings/net/qcom,ipq9574-ppe.yaml | 529 +++++++++++++++++++++
1 file changed, 529 insertions(+)
diff --git a/Documentation/devicetree/bindings/net/qcom,ipq9574-ppe.yaml b/Documentation/devicetree/bindings/net/qcom,ipq9574-ppe.yaml
new file mode 100644
index 000000000000..d48169a8ba7c
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/qcom,ipq9574-ppe.yaml
@@ -0,0 +1,529 @@
+# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/qcom,ipq9574-ppe.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm IPQ packet process engine (PPE)
+
+maintainers:
+ - Luo Jie <quic_luoj@xxxxxxxxxxx>
+ - Lei Wei <quic_leiwei@xxxxxxxxxxx>
+ - Suruchi Agarwal <quic_suruchia@xxxxxxxxxxx>
+ - Pavithra R <quic_pavir@xxxxxxxxxxx>
+
+description: |
+ The Ethernet functionality in the PPE (Packet Process Engine) is comprised
+ of three components, the switch core, port wrapper and Ethernet DMA.
+
+ The Switch core in the IPQ9574 PPE has maximum of 6 front panel ports and
+ two FIFO interfaces. One of the two FIFO interfaces is used for Ethernet
+ port to host CPU communication using Ethernet DMA. The other is used
+ communicating to the EIP engine which is used for IPsec offload. On the
+ IPQ9574, the PPE includes 6 GMAC/XGMACs that can be connected with external
+ Ethernet PHY. Switch core also includes BM (Buffer Management), QM (Queue
+ Management) and SCH (Scheduler) modules for supporting the packet processing.
+
+ The port wrapper provides connections from the 6 GMAC/XGMACS to UNIPHY (PCS)
+ supporting various modes such as SGMII/QSGMII/PSGMII/USXGMII/10G-BASER. There
+ are 3 UNIPHY (PCS) instances supported on the IPQ9574.
+
+ Ethernet DMA is used to transmit and receive packets between the six Ethernet
+ ports and ARM host CPU.
+
+ The follow diagram shows the PPE hardware block along with its connectivity
+ to the external hardware blocks such clock hardware blocks (CMNPLL, GCC,
+ NSS clock controller) and ethernet PCS/PHY blocks. For depicting the PHY
+ connectivity, one 4x1 Gbps PHY (QCA8075) and two 10 GBps PHYs are used as an
+ example.
+
+ +---------+
+ | 48 MHZ |
+ +----+----+
+ |(clock)
+ v
+ +----+----+
+ +------| CMN PLL |
+ | +----+----+
+ | |(clock)
+ | v
+ | +----+----+ +----+----+ (clock) +----+----+
+ | +---| NSSCC | | GCC |--------->| MDIO |
+ | | +----+----+ +----+----+ +----+----+
+ | | |(clock & reset) |(clock)
+ | | v v
+ | | +----+---------------------+--+----------+----------+---------+
+ | | | +-----+ |EDMA FIFO | | EIP FIFO|
+ | | | | SCH | +----------+ +---------+
+ | | | +-----+ | | |
+ | | | +------+ +------+ +-------------------+ |
+ | | | | BM | | QM | IPQ9574-PPE | L2/L3 Process | |
+ | | | +------+ +------+ +-------------------+ |
+ | | | | |
+ | | | +-------+ +-------+ +-------+ +-------+ +-------+ +-------+ |
+ | | | | MAC0 | | MAC1 | | MAC2 | | MAC3 | | XGMAC4| |XGMAC5 | |
+ | | | +---+---+ +---+---+ +---+---+ +---+---+ +---+---+ +---+---+ |
+ | | | | | | | | | |
+ | | +-----+---------+---------+---------+---------+---------+-----+
+ | | | | | | | |
+ | | +---+---------+---------+---------+---+ +---+---+ +---+---+
+ +--+---->| PCS0 | | PCS1 | | PCS2 |
+ |(clock) +---+---------+---------+---------+---+ +---+---+ +---+---+
+ | | | | | | |
+ | +---+---------+---------+---------+---+ +---+---+ +---+---+
+ +------->| QCA8075 PHY | | PHY4 | | PHY5 |
+ (clock) +-------------------------------------+ +-------+ +-------+
+
+properties:
+ compatible:
+ enum:
+ - qcom,ipq9574-ppe
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: PPE core clock from NSS clock controller
+ - description: PPE APB (Advanced Peripheral Bus) clock from NSS clock controller
+ - description: PPE ingress process engine clock from NSS clock controller
+ - description: PPE BM, QM and scheduler clock from NSS clock controller
Drop 'from NSS clock controller'. That's outside the scope of this
binding.
Ok, will update.
+
+ clock-names:
+ items:
+ - const: ppe
+ - const: apb
+ - const: ipe
+ - const: btq
+
+ resets:
+ maxItems: 1
+ description: PPE reset, which is necessary before configuring PPE hardware
+
+ interrupts:
+ maxItems: 1
+ description: PPE switch miscellaneous interrupt
+
+ interconnects:
+ items:
+ - description: Clock path leading to PPE switch core function
+ - description: Clock path leading to PPE register access
+ - description: Clock path leading to QoS generation
+ - description: Clock path leading to timeout reference
+ - description: Clock path leading to NSS NOC from memory NOC
+ - description: Clock path leading to memory NOC from NSS NOC
+ - description: Clock path leading to enhanced memory NOC from NSS NOC
Clock path? This should be bus interconnect paths.
Sure, I will use "bus interconnect path" for clarity.
+
+ interconnect-names:
+ items:
+ - const: ppe
+ - const: ppe_cfg
+ - const: qos_gen
+ - const: timeout_ref
+ - const: nssnoc_memnoc
+ - const: memnoc_nssnoc
+ - const: memnoc_nssnoc_1
+
+ ethernet-dma:
+ type: object
+ additionalProperties: false
+ description:
+ EDMA (Ethernet DMA) is used to transmit packets between PPE and ARM
+ host CPU. There are 32 TX descriptor rings, 32 TX completion rings,
+ 24 RX descriptor rings and 8 RX fill rings supported.
+
+ properties:
+ clocks:
+ items:
+ - description: EDMA system clock from NSS Clock Controller
+ - description: EDMA APB (Advanced Peripheral Bus) clock from
+ NSS Clock Controller
+
+ clock-names:
+ items:
+ - const: sys
+ - const: apb
+
+ resets:
+ maxItems: 1
+ description: EDMA reset from NSS clock controller
+
+ interrupts:
+ minItems: 65
+ maxItems: 65
+
+ interrupt-names:
+ minItems: 65
+ maxItems: 65
+ description:
+ Interrupts "txcmpl_[0-31]" are the Ethernet DMA TX completion ring interrupts.
+ Interrupts "rxfill_[0-7]" are the Ethernet DMA RX fill ring interrupts.
+ Interrupts "rxdesc_[0-23]" are the Ethernet DMA RX Descriptor ring interrupts.
+ Interrupt "misc" is the Ethernet DMA miscellaneous error interrupt.
items:
oneOf:
- pattern: '^txcmpl_([1-2]?[0-9]|3[01])$'
- pattern: '^rxfill_[0-7]$'
- pattern: '^rxdesc_(1?[0-9]|2[0-3])$'
- const: misc
Thanks for the suggestion, I will add the constraint.
+
+ required:
+ - clocks
+ - clock-names
+ - resets
+ - interrupts
+ - interrupt-names
+
+patternProperties:
+ "^(ethernet-)?ports$":
New binding, does 'ethernet-' part need to be optional? No.
OK, understand. Will update to make 'ethernet-' mandatory.
+ patternProperties:
+ "^ethernet-port@[1-6]+$":
+ type: object
+ unevaluatedProperties: false
+ $ref: ethernet-switch-port.yaml#
+
+ properties:
+ reg:
+ minimum: 1
+ maximum: 6
+ description: PPE Ethernet port ID
+
+ clocks:
+ items:
+ - description: Port MAC clock from NSS clock controller
+ - description: Port RX clock from NSS clock controller
+ - description: Port TX clock from NSS clock controller
+
+ clock-names:
+ items:
+ - const: mac
+ - const: rx
+ - const: tx
+
+ resets:
+ items:
+ - description: Port MAC reset from NSS clock controller
+ - description: Port RX reset from NSS clock controller
+ - description: Port TX reset from NSS clock controller
+
+ reset-names:
+ items:
+ - const: mac
+ - const: rx
+ - const: tx
+
+ required:
+ - reg
+ - clocks
+ - clock-names
+ - resets
+ - reset-names
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+ - resets
+ - interconnects
+ - interconnect-names
+ - ethernet-dma
+
+allOf:
+ - $ref: ethernet-switch.yaml
+
+unevaluatedProperties: false