Re: [PATCH] PCI: mediatek: Add system pm support for MT2712

Ryder Lee
2018-05-31T02:05:36Z

On Wed, 2018-05-30 at 10:35 +0800, honghui.zhang@mediatek.com wrote:
> From: Honghui Zhang <honghui.zhang@mediatek.com>
>
> The MTCMOS of PCIe Host for MT2712 will be off when system suspend, and all
> the internel control register will be reset after system resume. The PCIe
> link should be re-established and the related control register values should
> be re-set after system resume.
>
> Signed-off-by: Honghui Zhang <honghui.zhang@mediatek.com>
> CC: Ryder Lee <ryder.lee@mediatek.com>
> ---
> drivers/pci/host/pcie-mediatek.c | 82 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 82 insertions(+)
>
> diff --git a/drivers/pci/host/pcie-mediatek.c b/drivers/pci/host/pcie-mediatek.c
> index dabf1086..60f98d92 100644
> --- a/drivers/pci/host/pcie-mediatek.c
> +++ b/drivers/pci/host/pcie-mediatek.c
> @@ -132,12 +132,14 @@ struct mtk_pcie_port;
> /**
> * struct mtk_pcie_soc - differentiate between host generations
> * @need_fix_class_id: whether this host's class ID needed to be fixed or not
> + * @pm_support: whether the host's MTCMOS will be off when suspend
> * @ops: pointer to configuration access functions
> * @startup: pointer to controller setting functions
> * @setup_irq: pointer to initialize IRQ functions
> */
> struct mtk_pcie_soc {
> bool need_fix_class_id;
> + bool pm_support;
> struct pci_ops *ops;
> int (*startup)(struct mtk_pcie_port *port);
> int (*setup_irq)(struct mtk_pcie_port *port, struct device_node *node);
> @@ -1179,12 +1181,91 @@ static int mtk_pcie_probe(struct platform_device *pdev)
> return err;
> }
>
> +static int __maybe_unused mtk_pcie_suspend_noirq(struct device *dev)
> +{
> + struct platform_device *pdev;
> + struct mtk_pcie *pcie;
> + struct mtk_pcie_port *port;
> + const struct mtk_pcie_soc *soc;
> +
> + pdev = to_platform_device(dev);
> + pcie = platform_get_drvdata(pdev);

How about this -
struct mtk_pcie *pcie = dev_get_drvdata(dev);

> + soc = pcie->soc;
> + if (!soc->pm_support)
> + return 0;
> +
> + list_for_each_entry(port, &pcie->ports, list) {
> + clk_disable_unprepare(port->ahb_ck);
> + clk_disable_unprepare(port->sys_ck);
> + phy_power_off(port->phy);
> + }
> +
> + return 0;
> +}
> +
> +static int __maybe_unused mtk_pcie_resume_noirq(struct device *dev)
> +{
> + struct platform_device *pdev;
> + struct mtk_pcie *pcie;
> + struct mtk_pcie_port *port;
> + const struct mtk_pcie_soc *soc;
> + int ret;
> +
> + pdev = to_platform_device(dev);
> + pcie = platform_get_drvdata(pdev);

struct mtk_pcie *pcie = dev_get_drvdata(dev);

> + soc = pcie->soc;
> + if (!soc->pm_support)
> + return 0;
> +
> + list_for_each_entry(port, &pcie->ports, list) {
> + ret = phy_power_on(port->phy);
> + if (ret) {
> + dev_err(dev, "could not power on phy\n");
> + return ret;
> + }
> + ret = clk_prepare_enable(port->sys_ck);
> + if (ret) {
> + dev_err(dev, "enable sys clock error\n");
> + phy_power_off(port->phy);
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(port->ahb_ck);
> + if (ret) {
> + dev_err(dev, "enable ahb clock error\n");
> + phy_power_off(port->phy);
> + clk_disable_unprepare(port->sys_ck);
> + return ret;
> + }
> +
> + ret = soc->startup(port);
> + if (ret) {
> + dev_err(dev, "pcie linkup failed\n");
> + phy_power_off(port->phy);
> + clk_disable_unprepare(port->sys_ck);
> + clk_disable_unprepare(port->ahb_ck);
> + return ret;
> + }
> +
> + if (IS_ENABLED(CONFIG_PCI_MSI))
> + mtk_pcie_enable_msi(port);
> + }
> +
> + return 0;
> +}
> +