Re: [PATCH 11/19] PCI: keystone: Cleanup PHY handling

From: Kishon Vijay Abraham I
Date: Tue Oct 16 2018 - 23:22:41 EST


Lorenzo,

On Tuesday 16 October 2018 10:36 PM, Lorenzo Pieralisi wrote:
> On Mon, Oct 15, 2018 at 06:37:13PM +0530, Kishon Vijay Abraham I wrote:
>> Cleanup PHY handling by using devm_phy_optional_get to get PHYs if
>> the PHYs are optional, creating a device link between the PHY device
>> and the controller device and disable PHY on error cases here.
>> Also invoke phy_reset() as part of initializing PHY.
>
> Hi Kishon,
>
> it is a bit of nitpicking, I know it is annoying but when I read "Also"
> in commit logs there is almost certainly a reason to split the patch
> into logical standalone entities, this one looks like one.
>
> Every patch must be a self-contained change that, in case we have to
> revert it, must not affect other patches.
>
> There are some more patches in the series that would benefit from
> splitting so I kindly ask you to go through them and repost, we
> should still be able to hit v4.20.

Sure, I'll repost them.

Thanks
Kishon
>
> Thanks,
> Lorenzo
>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> drivers/pci/controller/dwc/pci-keystone.c | 126 +++++++++++++++++++---
>> 1 file changed, 110 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
>> index e22328f89c84..bf37609ad75b 100644
>> --- a/drivers/pci/controller/dwc/pci-keystone.c
>> +++ b/drivers/pci/controller/dwc/pci-keystone.c
>> @@ -105,6 +105,9 @@ struct keystone_pcie {
>>
>> int num_msi_host_irqs;
>> int msi_host_irqs[MAX_MSI_HOST_IRQS];
>> + int num_lanes;
>> + struct phy **phy;
>> + struct device_link **link;
>> struct device_node *msi_intc_np;
>> struct irq_domain *legacy_irq_domain;
>> struct device_node *np;
>> @@ -880,22 +883,61 @@ static const struct dw_pcie_ops ks_pcie_dw_pcie_ops = {
>> .link_up = ks_pcie_link_up,
>> };
>>
>> -static int __exit ks_pcie_remove(struct platform_device *pdev)
>> +static void ks_pcie_disable_phy(struct keystone_pcie *ks_pcie)
>> {
>> - struct keystone_pcie *ks_pcie = platform_get_drvdata(pdev);
>> + int num_lanes = ks_pcie->num_lanes;
>>
>> - clk_disable_unprepare(ks_pcie->clk);
>> + while (num_lanes--) {
>> + phy_power_off(ks_pcie->phy[num_lanes]);
>> + phy_exit(ks_pcie->phy[num_lanes]);
>> + }
>> +}
>> +
>> +static int ks_pcie_enable_phy(struct keystone_pcie *ks_pcie)
>> +{
>> + int i;
>> + int ret;
>> + int num_lanes = ks_pcie->num_lanes;
>> +
>> + for (i = 0; i < num_lanes; i++) {
>> + ret = phy_reset(ks_pcie->phy[i]);
>> + if (ret < 0)
>> + goto err_phy;
>> +
>> + ret = phy_init(ks_pcie->phy[i]);
>> + if (ret < 0)
>> + goto err_phy;
>> +
>> + ret = phy_power_on(ks_pcie->phy[i]);
>> + if (ret < 0) {
>> + phy_exit(ks_pcie->phy[i]);
>> + goto err_phy;
>> + }
>> + }
>>
>> return 0;
>> +
>> +err_phy:
>> + while (--i >= 0) {
>> + phy_power_off(ks_pcie->phy[i]);
>> + phy_exit(ks_pcie->phy[i]);
>> + }
>> +
>> + return ret;
>> }
>>
>> static int __init ks_pcie_probe(struct platform_device *pdev)
>> {
>> struct device *dev = &pdev->dev;
>> + struct device_node *np = dev->of_node;
>> struct dw_pcie *pci;
>> struct keystone_pcie *ks_pcie;
>> - struct phy *phy;
>> + struct device_link **link;
>> + struct phy **phy;
>> + u32 num_lanes;
>> + char name[10];
>> int ret;
>> + int i;
>>
>> ks_pcie = devm_kzalloc(dev, sizeof(*ks_pcie), GFP_KERNEL);
>> if (!ks_pcie)
>> @@ -908,29 +950,59 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
>> pci->dev = dev;
>> pci->ops = &ks_pcie_dw_pcie_ops;
>>
>> - ks_pcie->pci = pci;
>> + ret = of_property_read_u32(np, "num-lanes", &num_lanes);
>> + if (ret)
>> + num_lanes = 1;
>>
>> - /* initialize SerDes Phy if present */
>> - phy = devm_phy_get(dev, "pcie-phy");
>> - if (PTR_ERR_OR_ZERO(phy) == -EPROBE_DEFER)
>> - return PTR_ERR(phy);
>> + phy = devm_kzalloc(dev, sizeof(*phy) * num_lanes, GFP_KERNEL);
>> + if (!phy)
>> + return -ENOMEM;
>>
>> - if (!IS_ERR_OR_NULL(phy)) {
>> - ret = phy_init(phy);
>> - if (ret < 0)
>> - return ret;
>> + link = devm_kzalloc(dev, sizeof(*link) * num_lanes, GFP_KERNEL);
>> + if (!link)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < num_lanes; i++) {
>> + snprintf(name, sizeof(name), "pcie-phy%d", i);
>> + phy[i] = devm_phy_optional_get(dev, name);
>> + if (IS_ERR(phy[i])) {
>> + ret = PTR_ERR(phy[i]);
>> + goto err_link;
>> + }
>> +
>> + if (!phy[i])
>> + continue;
>> +
>> + link[i] = device_link_add(dev, &phy[i]->dev, DL_FLAG_STATELESS);
>> + if (!link[i]) {
>> + ret = -EINVAL;
>> + goto err_link;
>> + }
>> + }
>> +
>> + ks_pcie->np = np;
>> + ks_pcie->pci = pci;
>> + ks_pcie->link = link;
>> + ks_pcie->num_lanes = num_lanes;
>> + ks_pcie->phy = phy;
>> +
>> + ret = ks_pcie_enable_phy(ks_pcie);
>> + if (ret) {
>> + dev_err(dev, "failed to enable phy\n");
>> + goto err_link;
>> }
>>
>> - ks_pcie->np = dev->of_node;
>> platform_set_drvdata(pdev, ks_pcie);
>> ks_pcie->clk = devm_clk_get(dev, "pcie");
>> if (IS_ERR(ks_pcie->clk)) {
>> dev_err(dev, "Failed to get pcie rc clock\n");
>> - return PTR_ERR(ks_pcie->clk);
>> + ret = PTR_ERR(ks_pcie->clk);
>> + goto err_phy;
>> }
>> +
>> ret = clk_prepare_enable(ks_pcie->clk);
>> if (ret)
>> - return ret;
>> + goto err_phy;
>>
>> ret = ks_pcie_add_pcie_port(ks_pcie, pdev);
>> if (ret < 0)
>> @@ -940,9 +1012,31 @@ static int __init ks_pcie_probe(struct platform_device *pdev)
>> fail_clk:
>> clk_disable_unprepare(ks_pcie->clk);
>>
>> +err_phy:
>> + ks_pcie_disable_phy(ks_pcie);
>> +
>> +err_link:
>> + while (--i >= 0 && link[i])
>> + device_link_del(link[i]);
>> +
>> return ret;
>> }
>>
>> +static int __exit ks_pcie_remove(struct platform_device *pdev)
>> +{
>> + struct keystone_pcie *ks_pcie = platform_get_drvdata(pdev);
>> + struct device_link **link = ks_pcie->link;
>> + int num_lanes = ks_pcie->num_lanes;
>> +
>> + clk_disable_unprepare(ks_pcie->clk);
>> + ks_pcie_disable_phy(ks_pcie);
>> +
>> + while (num_lanes--)
>> + device_link_del(link[num_lanes]);
>> +
>> + return 0;
>> +}
>> +
>> static struct platform_driver ks_pcie_driver __refdata = {
>> .probe = ks_pcie_probe,
>> .remove = __exit_p(ks_pcie_remove),
>> --
>> 2.17.1
>>