From: Thierry Reding <treding@xxxxxxxxxx>
The current XUSB pad controller bindings are insufficient to describe
PHY devices attached to USB controllers. New bindings have been created
to overcome these restrictions. As a side-effect each root port now is
assigned a set of PHY devices, one for each lane associated with the
root port. This has the benefit of allowing fine-grained control of the
power management for each lane.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Changes in v5:
- fix power off sequence
Changes in v4:
- propagate failure from PHY power on
- refactor PHY power off sequence
Changes in v3:
- cache result of check for new PHY bindings usage (Stephen Warren)
Changes in v2:
- rework commit message to more accurately describe this change
drivers/pci/host/pci-tegra.c | 243 ++++++++++++++++++++++++++++++++++++++++---
1 file changed, 226 insertions(+), 17 deletions(-)
diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c
index 68d1f41b3cbf..12d581130645 100644
--- a/drivers/pci/host/pci-tegra.c
+++ b/drivers/pci/host/pci-tegra.c
@@ -295,6 +295,7 @@ struct tegra_pcie {
struct reset_control *afi_rst;
struct reset_control *pcie_xrst;
+ bool legacy_phy;
struct phy *phy;
struct tegra_msi msi;
@@ -311,11 +312,14 @@ struct tegra_pcie {
struct tegra_pcie_port {
struct tegra_pcie *pcie;
+ struct device_node *np;
struct list_head list;
struct resource regs;
void __iomem *base;
unsigned int index;
unsigned int lanes;
+
+ struct phy **phys;
};
struct tegra_pcie_bus {
@@ -860,6 +864,128 @@ static int tegra_pcie_phy_enable(struct tegra_pcie *pcie)
return 0;
}
+static int tegra_pcie_phy_disable(struct tegra_pcie *pcie)
+{
+ const struct tegra_pcie_soc_data *soc = pcie->soc_data;
+ u32 value;
+
+ /* disable TX/RX data */
+ value = pads_readl(pcie, PADS_CTL);
+ value &= ~(PADS_CTL_TX_DATA_EN_1L | PADS_CTL_RX_DATA_EN_1L);
+ pads_writel(pcie, value, PADS_CTL);
+
+ /* override IDDQ */
+ value = pads_readl(pcie, PADS_CTL);
+ value |= PADS_CTL_IDDQ_1L;
+ pads_writel(pcie, PADS_CTL, value);
+
+ /* reset PLL */
+ value = pads_readl(pcie, soc->pads_pll_ctl);
+ value &= ~PADS_PLL_CTL_RST_B4SM;
+ pads_writel(pcie, value, soc->pads_pll_ctl);
+
+ usleep_range(20, 100);
+
+ return 0;
+}
+
+static int tegra_pcie_port_phy_power_on(struct tegra_pcie_port *port)
+{
+ struct device *dev = port->pcie->dev;
+ unsigned int i;
+ int err;
+
+ for (i = 0; i < port->lanes; i++) {
+ err = phy_power_on(port->phys[i]);
+ if (err < 0) {
+ dev_err(dev, "failed to power on PHY#%u: %d\n", i,
+ err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int tegra_pcie_port_phy_power_off(struct tegra_pcie_port *port)
+{
+ struct device *dev = port->pcie->dev;
+ unsigned int i;
+ int err;
+
+ for (i = 0; i < port->lanes; i++) {
+ err = phy_power_off(port->phys[i]);
+ if (err < 0) {
+ dev_err(dev, "failed to power off PHY#%u: %d\n", i,
+ err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int tegra_pcie_phy_power_on(struct tegra_pcie *pcie)
+{
+ struct tegra_pcie_port *port;
+ int err;
+
+ if (pcie->legacy_phy) {
+ if (pcie->phy)
+ err = phy_power_on(pcie->phy);
+ else
+ err = tegra_pcie_phy_enable(pcie);
+
+ if (err < 0)
+ dev_err(pcie->dev, "failed to power on PHY: %d\n", err);
+
+ return err;
+ }
+
+ list_for_each_entry(port, &pcie->ports, list) {
+ err = tegra_pcie_port_phy_power_on(port);
+ if (err < 0) {
+ dev_err(pcie->dev,
+ "failed to power on PCIe port %u PHY: %d\n",
+ port->index, err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int tegra_pcie_phy_power_off(struct tegra_pcie *pcie)
+{
+ struct tegra_pcie_port *port;
+ int err;
+
+ if (pcie->legacy_phy) {
+ if (pcie->phy)
+ err = phy_power_off(pcie->phy);
+ else
+ err = tegra_pcie_phy_disable(pcie);
+
+ if (err < 0)
+ dev_err(pcie->dev, "failed to power off PHY: %d\n",
+ err);
+
+ return err;
+ }
+
+ list_for_each_entry(port, &pcie->ports, list) {
+ err = tegra_pcie_port_phy_power_off(port);
+ if (err < 0) {
+ dev_err(pcie->dev,
+ "failed to power off PCIe port %u PHY: %d\n",
+ port->index, err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
static int tegra_pcie_enable_controller(struct tegra_pcie *pcie)
{
const struct tegra_pcie_soc_data *soc = pcie->soc_data;
@@ -899,13 +1025,9 @@ static int tegra_pcie_enable_controller(struct tegra_pcie *pcie)
afi_writel(pcie, value, AFI_FUSE);
}
- if (!pcie->phy)
- err = tegra_pcie_phy_enable(pcie);
- else
- err = phy_power_on(pcie->phy);
-
+ err = tegra_pcie_phy_power_on(pcie);
if (err < 0) {
- dev_err(pcie->dev, "failed to power on PHY: %d\n", err);
+ dev_err(pcie->dev, "failed to power on PHY(s): %d\n", err);
return err;
}
@@ -942,9 +1064,9 @@ static void tegra_pcie_power_off(struct tegra_pcie *pcie)
/* TODO: disable and unprepare clocks? */
- err = phy_power_off(pcie->phy);
+ err = tegra_pcie_phy_power_off(pcie);
if (err < 0)
- dev_warn(pcie->dev, "failed to power off PHY: %d\n", err);
+ dev_err(pcie->dev, "failed to power off PHY(s): %d\n", err);
reset_control_assert(pcie->pcie_xrst);
reset_control_assert(pcie->afi_rst);
@@ -1049,6 +1171,99 @@ static int tegra_pcie_resets_get(struct tegra_pcie *pcie)
return 0;
}
+static int tegra_pcie_phys_get_legacy(struct tegra_pcie *pcie)
+{
+ int err;
+
+ pcie->phy = devm_phy_optional_get(pcie->dev, "pcie");
+ if (IS_ERR(pcie->phy)) {
+ err = PTR_ERR(pcie->phy);
+ dev_err(pcie->dev, "failed to get PHY: %d\n", err);
+ return err;
+ }
+
+ err = phy_init(pcie->phy);
+ if (err < 0) {
+ dev_err(pcie->dev, "failed to initialize PHY: %d\n", err);
+ return err;
+ }
+
+ pcie->legacy_phy = true;
+
+ return 0;
+}
+
+static struct phy *devm_of_phy_optional_get_index(struct device *dev,
+ struct device_node *np,
+ const char *consumer,
+ unsigned int index)
+{
+ struct phy *phy;
+ char *name;
+
+ name = kasprintf(GFP_KERNEL, "%s-%u", consumer, index);
+ if (!name)
+ return ERR_PTR(-ENOMEM);
+
+ phy = devm_of_phy_get(dev, np, name);
+ kfree(name);
+
+ if (IS_ERR(phy) && PTR_ERR(phy) == -ENODEV)
+ phy = NULL;
+
+ return phy;
+}
+
+static int tegra_pcie_port_get_phys(struct tegra_pcie_port *port)
+{
+ struct device *dev = port->pcie->dev;
+ struct phy *phy;
+ unsigned int i;
+ int err;
+
+ port->phys = devm_kcalloc(dev, sizeof(phy), port->lanes, GFP_KERNEL);
+ if (!port->phys)
+ return -ENOMEM;
+
+ for (i = 0; i < port->lanes; i++) {
+ phy = devm_of_phy_optional_get_index(dev, port->np, "pcie", i);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to get PHY#%u: %ld\n", i,
+ PTR_ERR(phy));
+ return PTR_ERR(phy);
+ }
+
+ err = phy_init(phy);
+ if (err < 0) {
+ dev_err(dev, "failed to initialize PHY#%u: %d\n", i,
+ err);
+ return err;
+ }
+
+ port->phys[i] = phy;
+ }
+
+ return 0;
+}
+
+static int tegra_pcie_phys_get(struct tegra_pcie *pcie)
+{
+ struct tegra_pcie_port *port;
+ int err;
+
+ if (of_get_property(pcie->dev->of_node, "phys", NULL) != NULL)
+ return tegra_pcie_phys_get_legacy(pcie);
+
+ list_for_each_entry(port, &pcie->ports, list) {
+ err = tegra_pcie_port_get_phys(port);
+ if (err < 0) {
+ return err;
+ }
+ }
+
+ return 0;
+}
+
static int tegra_pcie_get_resources(struct tegra_pcie *pcie)
{
struct platform_device *pdev = to_platform_device(pcie->dev);
@@ -1067,16 +1282,9 @@ static int tegra_pcie_get_resources(struct tegra_pcie *pcie)
return err;
}
- pcie->phy = devm_phy_optional_get(pcie->dev, "pcie");
- if (IS_ERR(pcie->phy)) {
- err = PTR_ERR(pcie->phy);
- dev_err(&pdev->dev, "failed to get PHY: %d\n", err);
- return err;
- }
-
- err = phy_init(pcie->phy);
+ err = tegra_pcie_phys_get(pcie);
if (err < 0) {
- dev_err(&pdev->dev, "failed to initialize PHY: %d\n", err);
+ dev_err(&pdev->dev, "failed to get PHYs: %d\n", err);
return err;
}
@@ -1752,6 +1960,7 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
rp->index = index;
rp->lanes = value;
rp->pcie = pcie;
+ rp->np = port;
rp->base = devm_ioremap_resource(pcie->dev, &rp->regs);
if (IS_ERR(rp->base))
--
2.8.0
--
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