Re: [PATCH v5 0/2] phy: qcom: qmp-pcie: Add PCIe PHY no_csr reset support

[Wenbin Yao (Consultant)]

On 2/26/2025 6:35 PM, Wenbin Yao wrote:
> The series aims to skip phy register programming and drive PCIe PHY with
> register setting programmed in bootloader by simply toggling no_csr reset,
> which once togglled, PHY hardware will be reset while PHY registers are
> retained.
>
> First, determine whether PHY setting can be skipped by checking
> QPHY_START_CTRL register and the existence of nocsr reset. If it is
> programmed and no_csr reset is supported, do no_csr reset and skip BCR
> reset which will reset entire PHY.
>
> This series also remove has_nocsr_reset flag in qmp_phy_cfg structure and
> decide whether the PHY supports nocsr reset by checking the existence of
> nocsr reset in device tree.
>
> The series are tested on X1E80100-QCP and HDK8550.
>
> The commit messages of this patchset have been modified based on comments
> and suggestions.
>
> Changes in v5:
> - Add a check whether the init sequences are exist if the PHY needs to be
>    initialized to Patch 2/2.
> - Link to v4: https://lore.kernel.org/all/20250220102253.755116-1-quic_wenbyao@xxxxxxxxxxx/
>
> Changes in v4:
> - Add Philipp's Reviewed-by tag to Patch 1/2.
> - Use PHY instead of phy in comments in Patch 2/2.
> - Use "if (qmp->nocsr_reset)" instead of "if (!qmp->nocsr_reset)" in
>    function qmp_pcie_exit for readability in Patch 2/2.
> - Use goto statements in function qmp_pcie_power_on and qmp_pcie_power_off
>    for readability in Patch 2/2.
> - Refine the comment of why not checking qmp->skip_init when reset PHY in
>    function qmp_pcie_power_off in Patch 2/2.
> - Link to v3: https://lore.kernel.org/all/20250214104539.281846-1-quic_wenbyao@xxxxxxxxxxx/
>
> Changes in v3:
> - Replace devm_reset_control_get_exclusive with
>    devm_reset_control_get_optional_exclusive when get phy_nocsr reset
>    control in Patch 1/2.
> - Do not ignore -EINVAL when get phy_nocsr reset control in Patch 1/2.
> - Replace phy_initialized with skip_init in struct qmp_pcie in Patch 2/2.
> - Add a comment to why not check qmp->skip_init in function
>    qmp_pcie_power_off in Patch 2/2.
> - Link to v2: https://lore.kernel.org/all/20250211094231.1813558-1-quic_wenbyao@xxxxxxxxxxx/
>
> Changes in v2:
> - Add Abel's and Manivannan's Reviewed-by tag to Patch 1/2.
> - Refine commit msg of Patch 2/2.
> - Link to v1: https://lore.kernel.org/all/20250121094140.4006801-1-quic_wenbyao@xxxxxxxxxxx/
>
> Konrad Dybcio (1):
>    phy: qcom: pcie: Determine has_nocsr_reset dynamically
>
> Qiang Yu (1):
>    phy: qcom: qmp-pcie: Add PHY register retention support
>
>   drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 86 +++++++++++++++++-------
>   1 file changed, 63 insertions(+), 23 deletions(-)
>
>
> base-commit: bcf2acd8f64b0a5783deeeb5fd70c6163ec5acd7

Hi, do you have any futher comments?

--
With best wishes
Wenbin