> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Grzegorz Nitka
> Sent: Wednesday, May 20, 2026 11:36 AM
> To: [email protected]
> Cc: Vecera, Ivan <[email protected]>; [email protected];
> [email protected]; [email protected]; [email protected]; Kitszel,
> Przemyslaw <[email protected]>; [email protected];
> [email protected]; [email protected]; Kubalewski,
> Arkadiusz <[email protected]>; [email protected];
> [email protected]; [email protected];
> [email protected]; Nguyen, Anthony L
> <[email protected]>; [email protected]; [email protected]
> Subject: [Intel-wired-lan] [PATCH v10 net-next 6/8] ice: implement CPI
> support for E825C
>
> Add full CPI (Converged PHY Interface) command handling required for
> E825C devices. The CPI interface allows the driver to interact with
> PHY-side control logic through the LM/PHY command registers, including
> enabling/disabling/selection of PHY reference clock.
>
> This patch introduces:
> - a new CPI subsystem (ice_cpi.c / ice_cpi.h) implementing the CPI
> request/acknowledge state machine, including REQ/ACK protocol,
> command execution, and response handling
> - helper functions for reading/writing PHY registers over Sideband
> Queue
> - CPI command execution API (ice_cpi_exec) and a helper for enabling
> or
> disabling Tx reference clocks (CPI 0xF1 opcode 'Config PHY
> clocking')
> - assurance of CPI transaction serialization into the CPI core.
> CPI REQ/ACK is a multi-step handshake and must be executed
> atomically per PHY. Centralize the lock in ice_cpi_exec() and
> use adapter-scoped per-PHY mutexes, which match the hardware
> sharing
> model across PFs.
> - addition of the non-posted write opcode (wr_np) to SBQ
> - Makefile integration to build CPI support together with the PTP
> stack
>
> This provides the infrastructure necessary to support PHY-side
> configuration flows on E825C and is required for advanced link control
> and Tx reference clock management.
>
> Reviewed-by: Arkadiusz Kubalewski <[email protected]>
> Signed-off-by: Grzegorz Nitka <[email protected]>
> ---
> drivers/net/ethernet/intel/ice/Makefile | 2 +-
> drivers/net/ethernet/intel/ice/ice_adapter.c | 4 +
> drivers/net/ethernet/intel/ice/ice_adapter.h | 7 +
> drivers/net/ethernet/intel/ice/ice_cpi.c | 362
> +++++++++++++++++++
> drivers/net/ethernet/intel/ice/ice_cpi.h | 58 +++
> drivers/net/ethernet/intel/ice/ice_sbq_cmd.h | 5 +-
> drivers/net/ethernet/intel/ice/ice_type.h | 2 +
> 7 files changed, 437 insertions(+), 3 deletions(-) create mode
> 100644 drivers/net/ethernet/intel/ice/ice_cpi.c
> create mode 100644 drivers/net/ethernet/intel/ice/ice_cpi.h
>
> diff --git a/drivers/net/ethernet/intel/ice/Makefile
> b/drivers/net/ethernet/intel/ice/Makefile
> index 5b2c666496e7..38db476ab2ec 100644
> --- a/drivers/net/ethernet/intel/ice/Makefile
> +++ b/drivers/net/ethernet/intel/ice/Makefile
> @@ -54,7 +54,7 @@ ice-$(CONFIG_PCI_IOV) += \
> ice_vf_mbx.o \
> ice_vf_vsi_vlan_ops.o \
> ice_vf_lib.o
...
> +
> +/**
> + * ice_cpi_set_cmd - execute CPI SET command
> + * @hw: pointer to the HW struct
> + * @opcode: CPI command opcode
> + * @phy: phy index CPI command is applied for
> + * @port_lane: ephy index CPI command is applied for
> + * @data: CPI opcode context specific data
> + *
> + * Return: 0 on success, negative error code on failure.
> + */
> +static int ice_cpi_set_cmd(struct ice_hw *hw, u16 opcode, u8 phy, u8
> port_lane,
> + u16 data)
> +{
> + struct ice_cpi_resp cpi_resp = {0};
> + struct ice_cpi_cmd cpi_cmd = {
> + .opcode = opcode,
Silent u16 to u8 truncation.
> + .set = true,
> + .port = port_lane,
> + .data = data,
> + };
> +
> + return ice_cpi_exec(hw, phy, &cpi_cmd, &cpi_resp); }
> +
...
> /* Port hardware description */
> struct ice_hw {
> u8 __iomem *hw_addr;
> --
> 2.39.3
