PCI: tegra: Put PEX CLK & BIAS pads in DPD mode

In Tegra210 AFI design has clamp value for the BIAS pad as 0, which keeps
the bias pad in non power down mode. This is leading to power consumption
of 2 mW in BIAS pad, even if the PCIe partition is powergated. To avoid
unnecessary power consumption, put PEX CLK & BIAS pads in deep power down
mode when PCIe partition is power gated.

Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
index 6be4ea72da92f70b1dffb3a09335f724a07684c9..0fd1c1a8c1b9f8bfec9e1477713d8ec4a5b73717 100644 (file)
--- a/drivers/pci/controller/pci-tegra.c
+++ b/drivers/pci/controller/pci-tegra.c
@@ -30,6 +30,7 @@
 #include <linux/of_platform.h>
 #include <linux/pci.h>
 #include <linux/phy/phy.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
 #include <linux/sizes.h>
@@ -2853,6 +2854,7 @@ static int __maybe_unused tegra_pcie_pm_suspend(struct device *dev)
        if (IS_ENABLED(CONFIG_PCI_MSI))
                tegra_pcie_disable_msi(pcie);
 
+       pinctrl_pm_select_idle_state(dev);
        tegra_pcie_power_off(pcie);
 
        return 0;
@@ -2868,6 +2870,13 @@ static int __maybe_unused tegra_pcie_pm_resume(struct device *dev)
                dev_err(dev, "tegra pcie power on fail: %d\n", err);
                return err;
        }
+
+       err = pinctrl_pm_select_default_state(dev);
+       if (err < 0) {
+               dev_err(dev, "failed to disable PCIe IO DPD: %d\n", err);
+               goto poweroff;
+       }
+
        tegra_pcie_enable_controller(pcie);
        tegra_pcie_setup_translations(pcie);
 
@@ -2877,7 +2886,7 @@ static int __maybe_unused tegra_pcie_pm_resume(struct device *dev)
        err = clk_prepare_enable(pcie->pex_clk);
        if (err) {
                dev_err(dev, "failed to enable PEX clock: %d\n", err);
-               goto poweroff;
+               goto pex_dpd_enable;
        }
 
        reset_control_deassert(pcie->pex_rst);
@@ -2898,6 +2907,8 @@ static int __maybe_unused tegra_pcie_pm_resume(struct device *dev)
 disable_pex_clk:
        reset_control_assert(pcie->pex_rst);
        clk_disable_unprepare(pcie->pex_clk);
+pex_dpd_enable:
+       pinctrl_pm_select_idle_state(dev);
 poweroff:
        tegra_pcie_power_off(pcie);