Re: [PATCH v7 09/10] PCI: imx6: Call common PHY API to set mode, speed, and submode

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

On Mon, Jul 08, 2024 at 01:08:13PM -0400, Frank Li wrote:
> Invoke the common PHY API to configure mode, speed, and submode. While
> these functions are optional in the PHY interface, they are necessary for
> certain PHY drivers. Lack of support for these functions in a PHY driver
> does not cause harm.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

I've mentioned an issue below which is unrelated to this patch, but please do
fix it (in a separate patch).

> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 57814a0cfab8c..c72c7a0b0e02d 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -29,6 +29,7 @@
>  #include <linux/types.h>
>  #include <linux/interrupt.h>
>  #include <linux/reset.h>
> +#include <linux/phy/pcie.h>
>  #include <linux/phy/phy.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_runtime.h>
> @@ -229,6 +230,10 @@ static void imx_pcie_configure_type(struct imx_pcie *imx_pcie)
>  
>  	id = imx_pcie->controller_id;
>  
> +	/* If mode_mask is 0, then generic PHY driver is used to set the mode */
> +	if (!drvdata->mode_mask[0])
> +		return;
> +
>  	/* If mode_mask[id] is zero, means each controller have its individual gpr */
>  	if (!drvdata->mode_mask[id])
>  		id = 0;
> @@ -807,7 +812,11 @@ static void imx_pcie_ltssm_enable(struct device *dev)
>  {
>  	struct imx_pcie *imx_pcie = dev_get_drvdata(dev);
>  	const struct imx_pcie_drvdata *drvdata = imx_pcie->drvdata;
> +	u8 offset = dw_pcie_find_capability(imx_pcie->pci, PCI_CAP_ID_EXP);
> +	u32 tmp;
>  
> +	tmp = dw_pcie_readl_dbi(imx_pcie->pci, offset + PCI_EXP_LNKCAP);
> +	phy_set_speed(imx_pcie->phy, FIELD_GET(PCI_EXP_LNKCAP_SLS, tmp));
>  	if (drvdata->ltssm_mask)
>  		regmap_update_bits(imx_pcie->iomuxc_gpr, drvdata->ltssm_off, drvdata->ltssm_mask,
>  				   drvdata->ltssm_mask);
> @@ -820,6 +829,7 @@ static void imx_pcie_ltssm_disable(struct device *dev)
>  	struct imx_pcie *imx_pcie = dev_get_drvdata(dev);
>  	const struct imx_pcie_drvdata *drvdata = imx_pcie->drvdata;
>  
> +	phy_set_speed(imx_pcie->phy, 0);
>  	if (drvdata->ltssm_mask)
>  		regmap_update_bits(imx_pcie->iomuxc_gpr, drvdata->ltssm_off,
>  				   drvdata->ltssm_mask, 0);
> @@ -955,6 +965,12 @@ static int imx_pcie_host_init(struct dw_pcie_rp *pp)
>  			goto err_clk_disable;
>  		}
>  
> +		ret = phy_set_mode_ext(imx_pcie->phy, PHY_MODE_PCIE, PHY_MODE_PCIE_RC);
> +		if (ret) {
> +			dev_err(dev, "unable to set PCIe PHY mode\n");
> +			goto err_phy_off;

'err_phy_off' should power off the PHY, right? But this label is used to do
phy_exit() which is wrong. Please rename this label to err_phy_exit and also
use _this_ label to power off the PHY after the failures of phy_power_on().
Right now, PHY is never turned off in error path.

- Mani

-- 
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