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

Robert Marko
2022-06-29T09:21:59Z

On Fri, 24 Jun 2022 at 12:44, Robert Marko <robimarko@gmail.com> 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@gmail.com>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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
>