[PATCH v4 3/4] PCI: tegra: Add Tegra264 support

Thierry Reding
2026-04-02T14:28:03Z

Add a driver for the PCIe controller found on NVIDIA Tegra264 SoCs. The
driver is very small, with its main purpose being to set up the address
translation registers and then creating a standard PCI host using ECAM.

Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
---
Changes in v2:
- specify generations applicable for PCI_TEGRA driver to avoid confusion
- drop SPDX-FileCopyrightText tag
- rename link_state to link_up to clarify meaning
- replace memset() by an empty initializer
- sanity-check only enable BAR regions
- bring PCI link out of reset in case firmware didn't
- use common wait times instead of defining our own
- use core helpers to parse and print PCI link speed
- fix multi-line comment
- use dev_err_probe() more ubiquitously
- fix probe sequence and error cleanup
- use DEFINE_NOIRQ_DEV_PM_OPS() to avoid warnings for !PM_SUSPEND
- reuse more standard registers and remove unused register definitions
- use %pe and ERR_PTR() to print symbolic errors
- add signed-off-by from Manikanta as the original author
- add myself as author after significantly modifying the driver
---
drivers/pci/controller/Kconfig | 10 +-
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-tegra264.c | 527 +++++++++++++++++++++++++++++++++
3 files changed, 537 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index 5aaed8ac6e44..6ead04f7bd6e 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -254,7 +254,15 @@ config PCI_TEGRA
select IRQ_MSI_LIB
help
Say Y here if you want support for the PCIe host controller found
- on NVIDIA Tegra SoCs.
+ on NVIDIA Tegra SoCs (Tegra20 through Tegra186).
+
+config PCIE_TEGRA264
+ bool "NVIDIA Tegra264 PCIe controller"
+ depends on ARCH_TEGRA || COMPILE_TEST
+ depends on PCI_MSI
+ help
+ Say Y here if you want support for the PCIe host controller found
+ on NVIDIA Tegra264 SoCs.

config PCIE_RCAR_HOST
bool "Renesas R-Car PCIe controller (host mode)"
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index ac8db283f0fe..d478743b5142 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_PCI_HYPERV_INTERFACE) += pci-hyperv-intf.o
obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
obj-$(CONFIG_PCI_AARDVARK) += pci-aardvark.o
obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
+obj-$(CONFIG_PCIE_TEGRA264) += pcie-tegra264.o
obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
obj-$(CONFIG_PCIE_RCAR_HOST) += pcie-rcar.o pcie-rcar-host.o
obj-$(CONFIG_PCIE_RCAR_EP) += pcie-rcar.o pcie-rcar-ep.o
diff --git a/drivers/pci/controller/pcie-tegra264.c b/drivers/pci/controller/pcie-tegra264.c
new file mode 100644
index 000000000000..3ce1ad971bdb
--- /dev/null
+++ b/drivers/pci/controller/pcie-tegra264.c
@@ -0,0 +1,527 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCIe host controller driver for Tegra264 SoC
+ *
+ * Copyright (c) 2022-2026, NVIDIA CORPORATION. All rights reserved.
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/interconnect.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci-ecam.h>
+#include <linux/pci.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <soc/tegra/bpmp.h>
+#include <soc/tegra/bpmp-abi.h>
+#include <soc/tegra/fuse.h>
+
+#include "../pci.h"
+
+/* XAL registers */
+#define XAL_RC_ECAM_BASE_HI 0x00
+#define XAL_RC_ECAM_BASE_LO 0x04
+#define XAL_RC_ECAM_BUSMASK 0x08
+#define XAL_RC_IO_BASE_HI 0x0c
+#define XAL_RC_IO_BASE_LO 0x10
+#define XAL_RC_IO_LIMIT_HI 0x14
+#define XAL_RC_IO_LIMIT_LO 0x18
+#define XAL_RC_MEM_32BIT_BASE_HI 0x1c
+#define XAL_RC_MEM_32BIT_BASE_LO 0x20
+#define XAL_RC_MEM_32BIT_LIMIT_HI 0x24
+#define XAL_RC_MEM_32BIT_LIMIT_LO 0x28
+#define XAL_RC_MEM_64BIT_BASE_HI 0x2c
+#define XAL_RC_MEM_64BIT_BASE_LO 0x30
+#define XAL_RC_MEM_64BIT_LIMIT_HI 0x34
+#define XAL_RC_MEM_64BIT_LIMIT_LO 0x38
+#define XAL_RC_BAR_CNTL_STANDARD 0x40
+#define XAL_RC_BAR_CNTL_STANDARD_IOBAR_EN BIT(0)
+#define XAL_RC_BAR_CNTL_STANDARD_32B_BAR_EN BIT(1)
+#define XAL_RC_BAR_CNTL_STANDARD_64B_BAR_EN BIT(2)
+
+/* XTL registers */
+#define XTL_RC_PCIE_CFG_LINK_STATUS 0x5a
+
+#define XTL_RC_MGMT_PERST_CONTROL 0x218
+#define XTL_RC_MGMT_PERST_CONTROL_PERST_O_N BIT(0)
+
+#define XTL_RC_MGMT_CLOCK_CONTROL 0x47c
+#define XTL_RC_MGMT_CLOCK_CONTROL_PEX_CLKREQ_I_N_PIN_USE_CONV_TO_PRSNT BIT(9)
+
+struct tegra264_pcie {
+ struct device *dev;
+ bool link_up;
+
+ /* I/O memory */
+ void __iomem *xal;
+ void __iomem *xtl;
+ void __iomem *ecam;
+
+ /* bridge configuration */
+ struct pci_config_window *cfg;
+ struct pci_host_bridge *bridge;
+
+ /* wake IRQ */
+ struct gpio_desc *wake_gpio;
+ unsigned int wake_irq;
+
+ /* BPMP and bandwidth management */
+ struct icc_path *icc_path;
+ struct tegra_bpmp *bpmp;
+ u32 ctl_id;
+};
+
+static int tegra264_pcie_parse_dt(struct tegra264_pcie *pcie)
+{
+ int err;
+
+ pcie->wake_gpio = devm_gpiod_get_optional(pcie->dev, "nvidia,pex-wake",
+ GPIOD_IN);
+ if (IS_ERR(pcie->wake_gpio))
+ return PTR_ERR(pcie->wake_gpio);
+
+ if (pcie->wake_gpio) {
+ device_init_wakeup(pcie->dev, true);
+
+ err = gpiod_to_irq(pcie->wake_gpio);
+ if (err < 0) {
+ dev_err(pcie->dev, "failed to get wake IRQ: %pe\n",
+ ERR_PTR(err));
+ return err;
+ }
+
+ pcie->wake_irq = (unsigned int)err;
+ }
+
+ return 0;
+}
+
+static void tegra264_pcie_bpmp_set_rp_state(struct tegra264_pcie *pcie)
+{
+ struct tegra_bpmp_message msg = {};
+ struct mrq_pcie_request req = {};
+ int err;
+
+ req.cmd = CMD_PCIE_RP_CONTROLLER_OFF;
+ req.rp_ctrlr_off.rp_controller = pcie->ctl_id;
+
+ msg.mrq = MRQ_PCIE;
+ msg.tx.data = &req;
+ msg.tx.size = sizeof(req);
+
+ err = tegra_bpmp_transfer(pcie->bpmp, &msg);
+ if (err)
+ dev_info(pcie->dev, "failed to turn off PCIe #%u: %pe\n",
+ pcie->ctl_id, ERR_PTR(err));
+
+ if (msg.rx.ret)
+ dev_info(pcie->dev, "failed to turn off PCIe #%u: %d\n",
+ pcie->ctl_id, msg.rx.ret);
+}
+
+static void tegra264_pcie_icc_set(struct tegra264_pcie *pcie)
+{
+ u32 value, speed, width, bw;
+ int err;
+
+ value = readw(pcie->ecam + XTL_RC_PCIE_CFG_LINK_STATUS);
+ speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, value);
+ width = FIELD_GET(PCI_EXP_LNKSTA_NLW, value);
+
+ bw = width * (PCIE_SPEED2MBS_ENC(speed) / BITS_PER_BYTE);
+ value = MBps_to_icc(bw);
+
+ err = icc_set_bw(pcie->icc_path, bw, bw);
+ if (err < 0)
+ dev_err(pcie->dev,
+ "failed to request bandwidth (%u MBps): %pe\n",
+ bw, ERR_PTR(err));
+}
+
+/*
+ * The various memory regions used by the controller (I/O, memory, ECAM) are
+ * set up during early boot and have hardware-level protections in place. If
+ * the DT ranges don't match what's been setup, the controller won't be able
+ * to write the address endpoints properly, so make sure to validate that DT
+ * and firmware programming agree on these ranges.
+ */
+static bool tegra264_pcie_check_ranges(struct platform_device *pdev)
+{
+ struct tegra264_pcie *pcie = platform_get_drvdata(pdev);
+ struct device_node *np = pcie->dev->of_node;
+ struct of_pci_range_parser parser;
+ phys_addr_t phys, limit, hi, lo;
+ struct of_pci_range range;
+ struct resource *res;
+ bool status = true;
+ u32 value;
+ int err;
+
+ err = of_pci_range_parser_init(&parser, np);
+ if (err < 0)
+ return false;
+
+ for_each_of_pci_range(&parser, &range) {
+ unsigned int addr_hi, addr_lo, limit_hi, limit_lo, enable;
+ unsigned long type = range.flags & IORESOURCE_TYPE_BITS;
+ phys_addr_t start, end, mask;
+ const char *region = NULL;
+
+ end = range.cpu_addr + range.size - 1;
+ start = range.cpu_addr;
+
+ switch (type) {
+ case IORESOURCE_IO:
+ addr_hi = XAL_RC_IO_BASE_HI;
+ addr_lo = XAL_RC_IO_BASE_LO;
+ limit_hi = XAL_RC_IO_LIMIT_HI;
+ limit_lo = XAL_RC_IO_LIMIT_LO;
+ enable = XAL_RC_BAR_CNTL_STANDARD_IOBAR_EN;
+ mask = SZ_64K - 1;
+ region = "I/O";
+ break;
+
+ case IORESOURCE_MEM:
+ if (range.flags & IORESOURCE_PREFETCH) {
+ addr_hi = XAL_RC_MEM_64BIT_BASE_HI;
+ addr_lo = XAL_RC_MEM_64BIT_BASE_LO;
+ limit_hi = XAL_RC_MEM_64BIT_LIMIT_HI;
+ limit_lo = XAL_RC_MEM_64BIT_LIMIT_LO;
+ enable = XAL_RC_BAR_CNTL_STANDARD_64B_BAR_EN;
+ region = "prefetchable memory";
+ } else {
+ addr_hi = XAL_RC_MEM_32BIT_BASE_HI;
+ addr_lo = XAL_RC_MEM_32BIT_BASE_LO;
+ limit_hi = XAL_RC_MEM_32BIT_LIMIT_HI;
+ limit_lo = XAL_RC_MEM_32BIT_LIMIT_LO;
+ enable = XAL_RC_BAR_CNTL_STANDARD_32B_BAR_EN;
+ region = "memory";
+ }
+
+ mask = SZ_1M - 1;
+ break;
+ }
+
+ /* not interested in anything that's not I/O or memory */
+ if (!region)
+ continue;
+
+ /* don't check regions that haven't been enabled */
+ value = readl(pcie->xal + XAL_RC_BAR_CNTL_STANDARD);
+ if ((value & enable) == 0)
+ continue;
+
+ hi = readl(pcie->xal + addr_hi);
+ lo = readl(pcie->xal + addr_lo);
+ phys = hi << 32 | lo;
+
+ hi = readl(pcie->xal + limit_hi);
+ lo = readl(pcie->xal + limit_lo);
+ limit = hi << 32 | lo | mask;
+
+ if (phys != start || limit != end) {
+ dev_err(pcie->dev,
+ "%s region mismatch: %pap-%pap -> %pap-%pap\n",
+ region, &phys, &limit, &start, &end);
+ status = false;
+ }
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ecam");
+ if (!res)
+ return false;
+
+ hi = readl(pcie->xal + XAL_RC_ECAM_BASE_HI);
+ lo = readl(pcie->xal + XAL_RC_ECAM_BASE_LO);
+ phys = hi << 32 | lo;
+
+ value = readl(pcie->xal + XAL_RC_ECAM_BUSMASK);
+ limit = phys + ((value + 1) << 20) - 1;
+
+ if (phys != res->start || limit != res->end) {
+ dev_err(pcie->dev,
+ "ECAM region mismatch: %pap-%pap -> %pap-%pap\n",
+ &phys, &limit, &res->start, &res->end);
+ status = false;
+ }
+
+ return status;
+}
+
+static bool tegra264_pcie_link_up(struct tegra264_pcie *pcie,
+ enum pci_bus_speed *speed)
+{
+ u16 value = readw(pcie->ecam + XTL_RC_PCIE_CFG_LINK_STATUS);
+
+ if (value & PCI_EXP_LNKSTA_DLLLA) {
+ if (speed)
+ *speed = pcie_link_speed[FIELD_GET(PCI_EXP_LNKSTA_CLS,
+ value)];
+
+ return true;
+ }
+
+ return false;
+}
+
+static void tegra264_pcie_init(struct tegra264_pcie *pcie)
+{
+ enum pci_bus_speed speed;
+ unsigned int i;
+ u32 value;
+
+ /* bring the link out of reset */
+ value = readl(pcie->xtl + XTL_RC_MGMT_PERST_CONTROL);
+ value |= XTL_RC_MGMT_PERST_CONTROL_PERST_O_N;
+ writel(value, pcie->xtl + XTL_RC_MGMT_PERST_CONTROL);
+
+ if (!tegra_is_silicon()) {
+ dev_info(pcie->dev,
+ "skipping link state for PCIe #%u in simulation\n",
+ pcie->ctl_id);
+ pcie->link_up = true;
+ return;
+ }
+
+ for (i = 0; i < PCIE_LINK_WAIT_MAX_RETRIES; i++) {
+ if (tegra264_pcie_link_up(pcie, NULL))
+ break;
+
+ usleep_range(PCIE_LINK_WAIT_US_MIN, PCIE_LINK_WAIT_US_MAX);
+ }
+
+ if (tegra264_pcie_link_up(pcie, &speed)) {
+ /* Per PCIe r5.0, 6.6.1 wait for 100ms after DLL up */
+ msleep(PCIE_RESET_CONFIG_WAIT_MS);
+
+ dev_info(pcie->dev, "PCIe #%u link is up (speed: %s)\n",
+ pcie->ctl_id, pci_speed_string(speed));
+ tegra264_pcie_icc_set(pcie);
+ pcie->link_up = true;
+ } else {
+ dev_info(pcie->dev, "PCIe #%u link is down\n", pcie->ctl_id);
+
+ value = readl(pcie->xtl + XTL_RC_MGMT_CLOCK_CONTROL);
+
+ /*
+ * Set link state only when link fails and no hot-plug feature
+ * is present.
+ */
+ if ((value & XTL_RC_MGMT_CLOCK_CONTROL_PEX_CLKREQ_I_N_PIN_USE_CONV_TO_PRSNT) == 0) {
+ dev_info(pcie->dev,
+ "PCIe #%u link is down and not hotplug-capable, turning off\n",
+ pcie->ctl_id);
+ tegra264_pcie_bpmp_set_rp_state(pcie);
+ pcie->link_up = false;
+ } else {
+ pcie->link_up = true;
+ }
+ }
+}
+
+static int tegra264_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pci_host_bridge *bridge;
+ struct tegra264_pcie *pcie;
+ struct resource_entry *bus;
+ struct resource *res;
+ int err;
+
+ bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct tegra264_pcie));
+ if (!bridge)
+ return dev_err_probe(dev, -ENOMEM,
+ "failed to allocate host bridge\n");
+
+ pcie = pci_host_bridge_priv(bridge);
+ platform_set_drvdata(pdev, pcie);
+ pcie->bridge = bridge;
+ pcie->dev = dev;
+
+ err = pinctrl_pm_select_default_state(dev);
+ if (err < 0)
+ return dev_err_probe(dev, err,
+ "failed to configure sideband pins\n");
+
+ err = tegra264_pcie_parse_dt(pcie);
+ if (err < 0)
+ return dev_err_probe(dev, err, "failed to parse device tree");
+
+ pcie->xal = devm_platform_ioremap_resource_byname(pdev, "xal");
+ if (IS_ERR(pcie->xal))
+ return dev_err_probe(dev, PTR_ERR(pcie->xal),
+ "failed to map XAL memory\n");
+
+ pcie->xtl = devm_platform_ioremap_resource_byname(pdev, "xtl-pri");
+ if (IS_ERR(pcie->xtl))
+ return dev_err_probe(dev, PTR_ERR(pcie->xtl),
+ "failed to map XTL-PRI memory\n");
+
+ bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
+ if (!bus)
+ return dev_err_probe(dev, -ENODEV,
+ "failed to get bus resources\n");
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ecam");
+ if (!res)
+ return dev_err_probe(dev, -ENXIO,
+ "failed to get ECAM resource\n");
+
+ pcie->icc_path = devm_of_icc_get(&pdev->dev, "write");
+ if (IS_ERR(pcie->icc_path))
+ return dev_err_probe(&pdev->dev, PTR_ERR(pcie->icc_path),
+ "failed to get ICC");
+
+ /*
+ * Parse BPMP property only for silicon, as interaction with BPMP is
+ * not needed for other platforms.
+ */
+ if (tegra_is_silicon()) {
+ pcie->bpmp = tegra_bpmp_get_with_id(dev, &pcie->ctl_id);
+ if (IS_ERR(pcie->bpmp))
+ return dev_err_probe(dev, PTR_ERR(pcie->bpmp),
+ "failed to get BPMP\n");
+ }
+
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+
+ /* sanity check that programmed ranges match what's in DT */
+ if (!tegra264_pcie_check_ranges(pdev)) {
+ err = -EINVAL;
+ goto put_pm;
+ }
+
+ pcie->cfg = pci_ecam_create(dev, res, bus->res, &pci_generic_ecam_ops);
+ if (IS_ERR(pcie->cfg)) {
+ err = dev_err_probe(dev, PTR_ERR(pcie->cfg),
+ "failed to create ECAM\n");
+ goto put_pm;
+ }
+
+ bridge->ops = (struct pci_ops *)&pci_generic_ecam_ops.pci_ops;
+ bridge->sysdata = pcie->cfg;
+ pcie->ecam = pcie->cfg->win;
+
+ tegra264_pcie_init(pcie);
+
+ if (!pcie->link_up)
+ goto free;
+
+ err = pci_host_probe(bridge);
+ if (err < 0) {
+ dev_err(dev, "failed to register host: %pe\n", ERR_PTR(err));
+ goto free;
+ }
+
+ return err;
+
+free:
+ pci_ecam_free(pcie->cfg);
+put_pm:
+ pm_runtime_put_sync(dev);
+ pm_runtime_disable(dev);
+
+ if (tegra_is_silicon())
+ tegra_bpmp_put(pcie->bpmp);
+
+ return err;
+}
+
+static void tegra264_pcie_remove(struct platform_device *pdev)
+{
+ struct tegra264_pcie *pcie = platform_get_drvdata(pdev);
+
+ /*
+ * If we undo tegra264_pcie_init() then link goes down and need
+ * controller reset to bring up the link again. Remove intention is
+ * to clean up the root bridge and re-enumerate during bind.
+ */
+ pci_lock_rescan_remove();
+ pci_stop_root_bus(pcie->bridge->bus);
+ pci_remove_root_bus(pcie->bridge->bus);
+ pci_unlock_rescan_remove();
+
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ if (tegra_is_silicon())
+ tegra_bpmp_put(pcie->bpmp);
+
+ pci_ecam_free(pcie->cfg);
+}
+
+static int tegra264_pcie_suspend_noirq(struct device *dev)
+{
+ struct tegra264_pcie *pcie = dev_get_drvdata(dev);
+ int err;
+
+ if (pcie->wake_gpio && device_may_wakeup(dev)) {
+ err = enable_irq_wake(pcie->wake_irq);
+ if (err < 0)
+ dev_err(dev, "failed to enable wake IRQ: %pe\n",
+ ERR_PTR(err));
+ }
+
+ return 0;
+}
+
+static int tegra264_pcie_resume_noirq(struct device *dev)
+{
+ struct tegra264_pcie *pcie = dev_get_drvdata(dev);
+ int err;
+
+ if (pcie->wake_gpio && device_may_wakeup(dev)) {
+ err = disable_irq_wake(pcie->wake_irq);
+ if (err < 0)
+ dev_err(dev, "failed to disable wake IRQ: %pe\n",
+ ERR_PTR(err));
+ }
+
+ if (pcie->link_up == false)
+ return 0;
+
+ tegra264_pcie_init(pcie);
+
+ return 0;
+}
+
+static DEFINE_NOIRQ_DEV_PM_OPS(tegra264_pcie_pm_ops,
+ tegra264_pcie_suspend_noirq,
+ tegra264_pcie_resume_noirq);
+
+static const struct of_device_id tegra264_pcie_of_match[] = {
+ {
+ .compatible = "nvidia,tegra264-pcie",
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tegra264_pcie_of_match);
+
+static struct platform_driver tegra264_pcie_driver = {
+ .probe = tegra264_pcie_probe,
+ .remove = tegra264_pcie_remove,
+ .driver = {
+ .name = "tegra264-pcie",
+ .pm = &tegra264_pcie_pm_ops,
+ .of_match_table = tegra264_pcie_of_match,
+ },
+};
+module_platform_driver(tegra264_pcie_driver);
+
+MODULE_AUTHOR("Manikanta Maddireddy <mmaddireddy@nvidia.com>");
+MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
+MODULE_DESCRIPTION("NVIDIA Tegra264 PCIe host controller driver");
+MODULE_LICENSE("GPL");

--
2.52.0