[PATCH v4 6/7] PCI: xilinx-nwl: Add phy support

Sean Anderson
2024-05-31T16:14:02Z

Add support for enabling/disabling PCIe phys. We can't really do
anything about failures in the disable/remove path, so just print an
error.

Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
---

Changes in v4:
- Remove if in err_phy
- Fix error path in phy_enable skipping the first phy
- Disable phys in reverse order
- Use dev_err instead of WARN for errors

Changes in v2:
- Get phys by index and not by name

drivers/pci/controller/pcie-xilinx-nwl.c | 84 +++++++++++++++++++++++-
1 file changed, 81 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
index e85158dc4e6c..d17630357999 100644
--- a/drivers/pci/controller/pcie-xilinx-nwl.c
+++ b/drivers/pci/controller/pcie-xilinx-nwl.c
@@ -19,6 +19,7 @@
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/pci-ecam.h>
+#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/irqchip/chained_irq.h>

@@ -157,6 +158,7 @@ struct nwl_pcie {
void __iomem *breg_base;
void __iomem *pcireg_base;
void __iomem *ecam_base;
+ struct phy *phy[4];
phys_addr_t phys_breg_base; /* Physical Bridge Register Base */
phys_addr_t phys_pcie_reg_base; /* Physical PCIe Controller Base */
phys_addr_t phys_ecam_base; /* Physical Configuration Base */
@@ -521,6 +523,60 @@ static int nwl_pcie_init_msi_irq_domain(struct nwl_pcie *pcie)
return 0;
}

+static void nwl_pcie_phy_power_off(struct nwl_pcie *pcie, int i)
+{
+ int err = phy_power_off(pcie->phy[i]);
+
+ if (err)
+ dev_err(pcie->dev, "could not power off phy %d (err=%d)\n", i,
+ err);
+}
+
+static void nwl_pcie_phy_exit(struct nwl_pcie *pcie, int i)
+{
+ int err = phy_exit(pcie->phy[i]);
+
+ if (err)
+ dev_err(pcie->dev, "could not exit phy %d (err=%d)\n", i, err);
+}
+
+static int nwl_pcie_phy_enable(struct nwl_pcie *pcie)
+{
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(pcie->phy); i++) {
+ ret = phy_init(pcie->phy[i]);
+ if (ret)
+ goto err;
+
+ ret = phy_power_on(pcie->phy[i]);
+ if (ret) {
+ nwl_pcie_phy_exit(pcie, i);
+ goto err;
+ }
+ }
+
+ return 0;
+
+err:
+ while (i--) {
+ nwl_pcie_phy_power_off(pcie, i);
+ nwl_pcie_phy_exit(pcie, i);
+ }
+
+ return ret;
+}
+
+static void nwl_pcie_phy_disable(struct nwl_pcie *pcie)
+{
+ int i;
+
+ for (i = ARRAY_SIZE(pcie->phy); i--;) {
+ nwl_pcie_phy_power_off(pcie, i);
+ nwl_pcie_phy_exit(pcie, i);
+ }
+}
+
static int nwl_pcie_init_irq_domain(struct nwl_pcie *pcie)
{
struct device *dev = pcie->dev;
@@ -732,6 +788,7 @@ static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
{
struct device *dev = pcie->dev;
struct resource *res;
+ int i;

res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "breg");
pcie->breg_base = devm_ioremap_resource(dev, res);
@@ -759,6 +816,18 @@ static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
irq_set_chained_handler_and_data(pcie->irq_intx,
nwl_pcie_leg_handler, pcie);

+
+ for (i = 0; i < ARRAY_SIZE(pcie->phy); i++) {
+ pcie->phy[i] = devm_of_phy_get_by_index(dev, dev->of_node, i);
+ if (PTR_ERR(pcie->phy[i]) == -ENODEV) {
+ pcie->phy[i] = NULL;
+ break;
+ }
+
+ if (IS_ERR(pcie->phy[i]))
+ return PTR_ERR(pcie->phy[i]);
+ }
+
return 0;
}

@@ -799,16 +868,22 @@ static int nwl_pcie_probe(struct platform_device *pdev)
return err;
}

+ err = nwl_pcie_phy_enable(pcie);
+ if (err) {
+ dev_err(dev, "could not enable PHYs\n");
+ goto err_clk;
+ }
+
err = nwl_pcie_bridge_init(pcie);
if (err) {
dev_err(dev, "HW Initialization failed\n");
- goto err_clk;
+ goto err_phy;
}

err = nwl_pcie_init_irq_domain(pcie);
if (err) {
dev_err(dev, "Failed creating IRQ Domain\n");
- goto err_clk;
+ goto err_phy;
}

bridge->sysdata = pcie;
@@ -818,7 +893,7 @@ static int nwl_pcie_probe(struct platform_device *pdev)
err = nwl_pcie_enable_msi(pcie);
if (err < 0) {
dev_err(dev, "failed to enable MSI support: %d\n", err);
- goto err_clk;
+ goto err_phy;
}
}

@@ -826,6 +901,8 @@ static int nwl_pcie_probe(struct platform_device *pdev)
if (!err)
return 0;

+err_phy:
+ nwl_pcie_phy_disable(pcie);
err_clk:
clk_disable_unprepare(pcie->clk);
return err;
@@ -835,6 +912,7 @@ static void nwl_pcie_remove(struct platform_device *pdev)
{
struct nwl_pcie *pcie = platform_get_drvdata(pdev);

+ nwl_pcie_phy_disable(pcie);
clk_disable_unprepare(pcie->clk);
}

--
2.35.1.1320.gc452695387.dirty