Re: [PATCH v3 01/11] PCI: qcom: add missing ipq806x clocks in PCIe driver

[Rob Herring]

On Fri, May 01, 2020 at 12:06:08AM +0200, Ansuel Smith wrote:
> Aux and Ref clk are missing in PCIe qcom driver.
> Add support in the driver to fix PCIe initialization in ipq806x.
> 
> Fixes: 82a823833f4e PCI: qcom: Add Qualcomm PCIe controller driver
> Signed-off-by: Sham Muthayyan <smuthayy@xxxxxxxxxxxxxx>
> Signed-off-by: Ansuel Smith <ansuelsmth@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx # v4.5+

Doesn't strike me as stable material. Looks like new h/w enablement.

> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 44 ++++++++++++++++++++++----
>  1 file changed, 38 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 5ea527a6bd9f..2a39dfdccfc8 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -88,6 +88,8 @@ struct qcom_pcie_resources_2_1_0 {
>  	struct clk *iface_clk;
>  	struct clk *core_clk;
>  	struct clk *phy_clk;
> +	struct clk *aux_clk;
> +	struct clk *ref_clk;
>  	struct reset_control *pci_reset;
>  	struct reset_control *axi_reset;
>  	struct reset_control *ahb_reset;
> @@ -246,6 +248,14 @@ static int qcom_pcie_get_resources_2_1_0(struct qcom_pcie *pcie)
>  	if (IS_ERR(res->phy_clk))
>  		return PTR_ERR(res->phy_clk);
>  
> +	res->aux_clk = devm_clk_get_optional(dev, "aux");
> +	if (IS_ERR(res->aux_clk))
> +		return PTR_ERR(res->aux_clk);
> +
> +	res->ref_clk = devm_clk_get_optional(dev, "ref");
> +	if (IS_ERR(res->ref_clk))
> +		return PTR_ERR(res->ref_clk);

Seems like you'd want to report an error for ipq608x? Based on the 
commit msg, they aren't optional.

> +
>  	res->pci_reset = devm_reset_control_get_exclusive(dev, "pci");
>  	if (IS_ERR(res->pci_reset))
>  		return PTR_ERR(res->pci_reset);
> @@ -278,6 +288,8 @@ static void qcom_pcie_deinit_2_1_0(struct qcom_pcie *pcie)
>  	clk_disable_unprepare(res->iface_clk);
>  	clk_disable_unprepare(res->core_clk);
>  	clk_disable_unprepare(res->phy_clk);
> +	clk_disable_unprepare(res->aux_clk);
> +	clk_disable_unprepare(res->ref_clk);
>  	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
>  }
>  
> @@ -307,16 +319,32 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
>  		goto err_assert_ahb;
>  	}
>  
> +	ret = clk_prepare_enable(res->core_clk);

Perhaps use the bulk api.

> +	if (ret) {
> +		dev_err(dev, "cannot prepare/enable core clock\n");
> +		goto err_clk_core;
> +	}
> +
>  	ret = clk_prepare_enable(res->phy_clk);
>  	if (ret) {
>  		dev_err(dev, "cannot prepare/enable phy clock\n");
>  		goto err_clk_phy;
>  	}
>  
> -	ret = clk_prepare_enable(res->core_clk);
> -	if (ret) {
> -		dev_err(dev, "cannot prepare/enable core clock\n");
> -		goto err_clk_core;
> +	if (res->aux_clk) {
> +		ret = clk_prepare_enable(res->aux_clk);
> +		if (ret) {
> +			dev_err(dev, "cannot prepare/enable aux clock\n");
> +			goto err_clk_aux;
> +		}
> +	}
> +
> +	if (res->ref_clk) {
> +		ret = clk_prepare_enable(res->ref_clk);
> +		if (ret) {
> +			dev_err(dev, "cannot prepare/enable ref clock\n");
> +			goto err_clk_ref;
> +		}
>  	}
>  
>  	ret = reset_control_deassert(res->ahb_reset);
> @@ -372,10 +400,14 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
>  	return 0;
>  
>  err_deassert_ahb:
> -	clk_disable_unprepare(res->core_clk);
> -err_clk_core:
> +	clk_disable_unprepare(res->ref_clk);
> +err_clk_ref:
> +	clk_disable_unprepare(res->aux_clk);
> +err_clk_aux:
>  	clk_disable_unprepare(res->phy_clk);
>  err_clk_phy:
> +	clk_disable_unprepare(res->core_clk);
> +err_clk_core:
>  	clk_disable_unprepare(res->iface_clk);
>  err_assert_ahb:
>  	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
> -- 
> 2.25.1
>