> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Grzegorz Nitka
> Sent: Tuesday, September 23, 2025 5:29 PM
> To: [email protected]
> Cc: [email protected]; Karol Kolacinski
> <[email protected]>; Kubalewski, Arkadiusz
> <[email protected]>
> Subject: [Intel-wired-lan] [PATCH iwl-net] ice: fix destination CGU
> for dual complex E825
>
> On dual complex E825, only complex 0 has functional CGU (Clock
> Generation Unit), powering all the PHYs.
> SBQ (Side Band Queue) destination device 'cgu' in current
> implementation
> points to CGU on current complex and, in order to access primary CGU
> from the secondary complex, the driver should use 'cgu_peer' as
> a destination device in read/write CGU registers operations.
>
> Define new 'cgu_peer' (15) as RDA (Remote Device Access) client over
> SB-IOSF interface and use it as device target when accessing CGU from
> secondary complex.
>
> This problem has been identified when working on recovery clock
> enablement [1]. In existing implementation for E825 devices, only PF0,
> which is clock owner, is involved in CGU configuration, thus the
> problem was not exposed to the user.
>
> [1] https://patchwork.ozlabs.org/project/intel-wired-
> lan/patch/[email protected]/
>
> Fixes: e2193f9f9ec9 ("ice: enable timesync operation on 2xNAC E825
> devices")
> Signed-off-by: Grzegorz Nitka <[email protected]>
> Signed-off-by: Karol Kolacinski <[email protected]>
> Reviewed-by: Arkadiusz Kubalewski <[email protected]>
> ---
> drivers/net/ethernet/intel/ice/ice_common.c | 30 ++++++++++++++++++-
> -
> drivers/net/ethernet/intel/ice/ice_sbq_cmd.h | 1 +
> 2 files changed, 29 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ice/ice_common.c
> b/drivers/net/ethernet/intel/ice/ice_common.c
> index eb6abf452b05..5ea420c76f54 100644
> --- a/drivers/net/ethernet/intel/ice/ice_common.c
> +++ b/drivers/net/ethernet/intel/ice/ice_common.c
> @@ -6382,6 +6382,32 @@ u32 ice_get_link_speed(u16 index)
> return ice_aq_to_link_speed[index];
> }
>
> +/**
> + * ice_get_dest_cgu - get destination CGU dev for given HW
> + * @hw: pointer to the HW struct
> + *
> + * Get CGU client id for CGU register read/write operations.
> + *
> + * Return:
> + * * ice_sbq_dev_cgu - default value
> + * * ice_sbq_dev_cgu_peer - when accessing CGU from 2nd complex (E825
> only)
> + *
> + */
NIT: In kernel‑doc for functions, Return: is expected to be prose (not bullet
items).
Also, prefer “second” to “2nd”, and describe what is returned rather than
enumerating constants.
> +static enum ice_sbq_dev_id ice_get_dest_cgu(struct ice_hw *hw)
> +{
> + /* On dual complex E825 only complex 0 has functional CGU
> powering all
> + * the PHYs.
> + * SBQ destination device cgu points to CGU on a current
> complex and to
> + * access primary CGU from the secondary complex, the driver
> should use
> + * cgu_peer as a destination device.
> + */
> + if (hw->mac_type == ICE_MAC_GENERIC_3K_E825 && ice_is_dual(hw)
> &&
> + !ice_is_primary(hw))
> + return ice_sbq_dev_cgu_peer;
> + else
> + return ice_sbq_dev_cgu;
> +}
Kernel style prefers dropping else when the if branch returns—makes the code
shorter and idiomatic.
> +
> /**
> * ice_read_cgu_reg - Read a CGU register
> * @hw: Pointer to the HW struct
> @@ -6396,8 +6422,8 @@ u32 ice_get_link_speed(u16 index)
> int ice_read_cgu_reg(struct ice_hw *hw, u32 addr, u32 *val)
> {
> struct ice_sbq_msg_input cgu_msg = {
> + .dest_dev = ice_get_dest_cgu(hw),
> .opcode = ice_sbq_msg_rd,
> - .dest_dev = ice_sbq_dev_cgu,
> .msg_addr_low = addr
> };
> int err;
> @@ -6428,8 +6454,8 @@ int ice_read_cgu_reg(struct ice_hw *hw, u32
> addr, u32 *val)
> int ice_write_cgu_reg(struct ice_hw *hw, u32 addr, u32 val)
> {
> struct ice_sbq_msg_input cgu_msg = {
> + .dest_dev = ice_get_dest_cgu(hw),
> .opcode = ice_sbq_msg_wr,
> - .dest_dev = ice_sbq_dev_cgu,
> .msg_addr_low = addr,
> .data = val
> };
> diff --git a/drivers/net/ethernet/intel/ice/ice_sbq_cmd.h
> b/drivers/net/ethernet/intel/ice/ice_sbq_cmd.h
> index 183dd5457d6a..21bb861febbf 100644
> --- a/drivers/net/ethernet/intel/ice/ice_sbq_cmd.h
> +++ b/drivers/net/ethernet/intel/ice/ice_sbq_cmd.h
> @@ -50,6 +50,7 @@ enum ice_sbq_dev_id {
> ice_sbq_dev_phy_0 = 0x02,
> ice_sbq_dev_cgu = 0x06,
> ice_sbq_dev_phy_0_peer = 0x0D,
> + ice_sbq_dev_cgu_peer = 0x0F,
> };
>
> enum ice_sbq_msg_opcode {
>
> base-commit: 84cb3483445f9ac0a106eb846fa100393433d469
> --
> 2.39.3
Some style warnings, otherwise fine.
Reviewed-by: Aleksandr Loktionov <[email protected]>
