Re: [PATCH v4 1/2] PCI: qcom: Move IPQ8074 DBI register accesses after phy_power_on()

[Robert Marko]

On Fri, 24 Jun 2022 at 12:44, Robert Marko <robimarko@xxxxxxxxx> wrote:
>
> Currently the Gen2 port in IPQ8074 will cause the system to hang as it
> accesses DBI registers in qcom_pcie_init_2_3_3(), and those are only
> accesible after phy_power_on().
>
> Move the DBI read/writes to a new qcom_pcie_post_init_2_3_3(), which is
> executed after phy_power_on().
>
> Fixes: a0fd361db8e5 ("PCI: dwc: Move "dbi", "dbi2", and "addr_space" resource setup into common code")
> Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

Hi,
Bjorn, is there something else I need to fixup?

Regards,
Robert
> ---
> Changes in v4:
> * Correct title and description
>
> Changes in v3:
> * Make sure it applies onto 5.19-rc3
> * Update the commit description to make it clear this only affects the
> Gen2 port
>
> Changes in v2:
> * Rebase onto next-20220621
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 48 +++++++++++++++-----------
>  1 file changed, 28 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index a1f1aca2fb59..24708d5d817d 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -1061,9 +1061,7 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
>         struct qcom_pcie_resources_2_3_3 *res = &pcie->res.v2_3_3;
>         struct dw_pcie *pci = pcie->pci;
>         struct device *dev = pci->dev;
> -       u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
>         int i, ret;
> -       u32 val;
>
>         for (i = 0; i < ARRAY_SIZE(res->rst); i++) {
>                 ret = reset_control_assert(res->rst[i]);
> @@ -1120,6 +1118,33 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
>                 goto err_clk_aux;
>         }
>
> +       return 0;
> +
> +err_clk_aux:
> +       clk_disable_unprepare(res->ahb_clk);
> +err_clk_ahb:
> +       clk_disable_unprepare(res->axi_s_clk);
> +err_clk_axi_s:
> +       clk_disable_unprepare(res->axi_m_clk);
> +err_clk_axi_m:
> +       clk_disable_unprepare(res->iface);
> +err_clk_iface:
> +       /*
> +        * Not checking for failure, will anyway return
> +        * the original failure in 'ret'.
> +        */
> +       for (i = 0; i < ARRAY_SIZE(res->rst); i++)
> +               reset_control_assert(res->rst[i]);
> +
> +       return ret;
> +}
> +
> +static int qcom_pcie_post_init_2_3_3(struct qcom_pcie *pcie)
> +{
> +       struct dw_pcie *pci = pcie->pci;
> +       u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> +       u32 val;
> +
>         writel(SLV_ADDR_SPACE_SZ,
>                 pcie->parf + PCIE20_v3_PARF_SLV_ADDR_SPACE_SIZE);
>
> @@ -1147,24 +1172,6 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
>                 PCI_EXP_DEVCTL2);
>
>         return 0;
> -
> -err_clk_aux:
> -       clk_disable_unprepare(res->ahb_clk);
> -err_clk_ahb:
> -       clk_disable_unprepare(res->axi_s_clk);
> -err_clk_axi_s:
> -       clk_disable_unprepare(res->axi_m_clk);
> -err_clk_axi_m:
> -       clk_disable_unprepare(res->iface);
> -err_clk_iface:
> -       /*
> -        * Not checking for failure, will anyway return
> -        * the original failure in 'ret'.
> -        */
> -       for (i = 0; i < ARRAY_SIZE(res->rst); i++)
> -               reset_control_assert(res->rst[i]);
> -
> -       return ret;
>  }
>
>  static int qcom_pcie_get_resources_2_7_0(struct qcom_pcie *pcie)
> @@ -1596,6 +1603,7 @@ static const struct qcom_pcie_ops ops_2_4_0 = {
>  static const struct qcom_pcie_ops ops_2_3_3 = {
>         .get_resources = qcom_pcie_get_resources_2_3_3,
>         .init = qcom_pcie_init_2_3_3,
> +       .post_init = qcom_pcie_post_init_2_3_3,
>         .deinit = qcom_pcie_deinit_2_3_3,
>         .ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
>  };
> --
> 2.36.1
>