1 files changed, 333 insertions, 0 deletions

diff --git a/drivers/misc/rp1/rp1_pci.c b/drivers/misc/rp1/rp1_pci.c
new file mode 100644
index 000000000000..803832006ec8
--- /dev/null
+++ b/drivers/misc/rp1/rp1_pci.c
@@ -0,0 +1,333 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018-2025 Raspberry Pi Ltd.
+ *
+ * All rights reserved.
+ */
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+
+#define RP1_HW_IRQ_MASK		GENMASK(5, 0)
+
+#define REG_SET			0x800
+#define REG_CLR			0xc00
+
+/* MSI-X CFG registers start at 0x8 */
+#define MSIX_CFG(x) (0x8 + (4 * (x)))
+
+#define MSIX_CFG_IACK_EN        BIT(3)
+#define MSIX_CFG_IACK           BIT(2)
+#define MSIX_CFG_ENABLE         BIT(0)
+
+/* Address map */
+#define RP1_PCIE_APBS_BASE	0x108000
+
+/* Interrupts */
+#define RP1_INT_END		61
+
+/* Embedded dtbo symbols created by cmd_wrap_S_dtb in scripts/Makefile.lib */
+extern char __dtbo_rp1_pci_begin[];
+extern char __dtbo_rp1_pci_end[];
+
+struct rp1_dev {
+	struct pci_dev *pdev;
+	struct irq_domain *domain;
+	struct irq_data *pcie_irqds[64];
+	void __iomem *bar1;
+	int ovcs_id;	/* overlay changeset id */
+	bool level_triggered_irq[RP1_INT_END];
+};
+
+static void msix_cfg_set(struct rp1_dev *rp1, unsigned int hwirq, u32 value)
+{
+	iowrite32(value, rp1->bar1 + RP1_PCIE_APBS_BASE + REG_SET + MSIX_CFG(hwirq));
+}
+
+static void msix_cfg_clr(struct rp1_dev *rp1, unsigned int hwirq, u32 value)
+{
+	iowrite32(value, rp1->bar1 + RP1_PCIE_APBS_BASE + REG_CLR + MSIX_CFG(hwirq));
+}
+
+static void rp1_mask_irq(struct irq_data *irqd)
+{
+	struct rp1_dev *rp1 = irqd->domain->host_data;
+	struct irq_data *pcie_irqd = rp1->pcie_irqds[irqd->hwirq];
+
+	pci_msi_mask_irq(pcie_irqd);
+}
+
+static void rp1_unmask_irq(struct irq_data *irqd)
+{
+	struct rp1_dev *rp1 = irqd->domain->host_data;
+	struct irq_data *pcie_irqd = rp1->pcie_irqds[irqd->hwirq];
+
+	pci_msi_unmask_irq(pcie_irqd);
+}
+
+static int rp1_irq_set_type(struct irq_data *irqd, unsigned int type)
+{
+	struct rp1_dev *rp1 = irqd->domain->host_data;
+	unsigned int hwirq = (unsigned int)irqd->hwirq;
+
+	switch (type) {
+	case IRQ_TYPE_LEVEL_HIGH:
+		dev_dbg(&rp1->pdev->dev, "MSIX IACK EN for IRQ %u\n", hwirq);
+		msix_cfg_set(rp1, hwirq, MSIX_CFG_IACK_EN);
+		rp1->level_triggered_irq[hwirq] = true;
+	break;
+	case IRQ_TYPE_EDGE_RISING:
+		msix_cfg_clr(rp1, hwirq, MSIX_CFG_IACK_EN);
+		rp1->level_triggered_irq[hwirq] = false;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct irq_chip rp1_irq_chip = {
+	.name		= "rp1_irq_chip",
+	.irq_mask	= rp1_mask_irq,
+	.irq_unmask	= rp1_unmask_irq,
+	.irq_set_type	= rp1_irq_set_type,
+};
+
+static void rp1_chained_handle_irq(struct irq_desc *desc)
+{
+	unsigned int hwirq = desc->irq_data.hwirq & RP1_HW_IRQ_MASK;
+	struct rp1_dev *rp1 = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	unsigned int virq;
+
+	chained_irq_enter(chip, desc);
+
+	virq = irq_find_mapping(rp1->domain, hwirq);
+	generic_handle_irq(virq);
+	if (rp1->level_triggered_irq[hwirq])
+		msix_cfg_set(rp1, hwirq, MSIX_CFG_IACK);
+
+	chained_irq_exit(chip, desc);
+}
+
+static int rp1_irq_xlate(struct irq_domain *d, struct device_node *node,
+			 const u32 *intspec, unsigned int intsize,
+			 unsigned long *out_hwirq, unsigned int *out_type)
+{
+	struct rp1_dev *rp1 = d->host_data;
+	struct irq_data *pcie_irqd;
+	unsigned long hwirq;
+	int pcie_irq;
+	int ret;
+
+	ret = irq_domain_xlate_twocell(d, node, intspec, intsize,
+				       &hwirq, out_type);
+	if (ret)
+		return ret;
+
+	pcie_irq = pci_irq_vector(rp1->pdev, hwirq);
+	pcie_irqd = irq_get_irq_data(pcie_irq);
+	rp1->pcie_irqds[hwirq] = pcie_irqd;
+	*out_hwirq = hwirq;
+
+	return 0;
+}
+
+static int rp1_irq_activate(struct irq_domain *d, struct irq_data *irqd,
+			    bool reserve)
+{
+	struct rp1_dev *rp1 = d->host_data;
+
+	msix_cfg_set(rp1, (unsigned int)irqd->hwirq, MSIX_CFG_ENABLE);
+
+	return 0;
+}
+
+static void rp1_irq_deactivate(struct irq_domain *d, struct irq_data *irqd)
+{
+	struct rp1_dev *rp1 = d->host_data;
+
+	msix_cfg_clr(rp1, (unsigned int)irqd->hwirq, MSIX_CFG_ENABLE);
+}
+
+static const struct irq_domain_ops rp1_domain_ops = {
+	.xlate      = rp1_irq_xlate,
+	.activate   = rp1_irq_activate,
+	.deactivate = rp1_irq_deactivate,
+};
+
+static void rp1_unregister_interrupts(struct pci_dev *pdev)
+{
+	struct rp1_dev *rp1 = pci_get_drvdata(pdev);
+	int irq, i;
+
+	if (rp1->domain) {
+		for (i = 0; i < RP1_INT_END; i++) {
+			irq = irq_find_mapping(rp1->domain, i);
+			irq_dispose_mapping(irq);
+		}
+
+		irq_domain_remove(rp1->domain);
+	}
+
+	pci_free_irq_vectors(pdev);
+}
+
+static int rp1_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	u32 dtbo_size = __dtbo_rp1_pci_end - __dtbo_rp1_pci_begin;
+	void *dtbo_start = __dtbo_rp1_pci_begin;
+	struct device *dev = &pdev->dev;
+	struct device_node *rp1_node;
+	bool skip_ovl = true;
+	struct rp1_dev *rp1;
+	int err = 0;
+	int i;
+
+	/*
+	 * Either use rp1_nexus node if already present in DT, or
+	 * set a flag to load it from overlay at runtime
+	 */
+	rp1_node = of_find_node_by_name(NULL, "rp1_nexus");
+	if (!rp1_node) {
+		rp1_node = dev_of_node(dev);
+		skip_ovl = false;
+	}
+
+	if (!rp1_node) {
+		dev_err(dev, "Missing of_node for device\n");
+		err = -EINVAL;
+		goto err_put_node;
+	}
+
+	rp1 = devm_kzalloc(&pdev->dev, sizeof(*rp1), GFP_KERNEL);
+	if (!rp1) {
+		err = -ENOMEM;
+		goto err_put_node;
+	}
+
+	rp1->pdev = pdev;
+
+	if (pci_resource_len(pdev, 1) <= 0x10000) {
+		dev_err(&pdev->dev,
+			"Not initialized - is the firmware running?\n");
+		err = -EINVAL;
+		goto err_put_node;
+	}
+
+	err = pcim_enable_device(pdev);
+	if (err < 0) {
+		err = dev_err_probe(&pdev->dev, err,
+				    "Enabling PCI device has failed");
+		goto err_put_node;
+	}
+
+	rp1->bar1 = pcim_iomap(pdev, 1, 0);
+	if (!rp1->bar1) {
+		dev_err(&pdev->dev, "Cannot map PCI BAR\n");
+		err = -EIO;
+		goto err_put_node;
+	}
+
+	pci_set_master(pdev);
+
+	err = pci_alloc_irq_vectors(pdev, RP1_INT_END, RP1_INT_END,
+				    PCI_IRQ_MSIX);
+	if (err < 0) {
+		err = dev_err_probe(&pdev->dev, err,
+				    "Failed to allocate MSI-X vectors\n");
+		goto err_put_node;
+	} else if (err != RP1_INT_END) {
+		dev_err(&pdev->dev, "Cannot allocate enough interrupts\n");
+		err = -EINVAL;
+		goto err_put_node;
+	}
+
+	pci_set_drvdata(pdev, rp1);
+	rp1->domain = irq_domain_add_linear(rp1_node, RP1_INT_END,
+					    &rp1_domain_ops, rp1);
+	if (!rp1->domain) {
+		dev_err(&pdev->dev, "Error creating IRQ domain\n");
+		err = -ENOMEM;
+		goto err_unregister_interrupts;
+	}
+
+	for (i = 0; i < RP1_INT_END; i++) {
+		unsigned int irq = irq_create_mapping(rp1->domain, i);
+
+		if (!irq) {
+			dev_err(&pdev->dev, "Failed to create IRQ mapping\n");
+			err = -EINVAL;
+			goto err_unregister_interrupts;
+		}
+
+		irq_set_chip_and_handler(irq, &rp1_irq_chip, handle_level_irq);
+		irq_set_probe(irq);
+		irq_set_chained_handler_and_data(pci_irq_vector(pdev, i),
+						 rp1_chained_handle_irq, rp1);
+	}
+
+	if (!skip_ovl) {
+		err = of_overlay_fdt_apply(dtbo_start, dtbo_size, &rp1->ovcs_id,
+					   rp1_node);
+		if (err)
+			goto err_unregister_interrupts;
+	}
+
+	err = of_platform_default_populate(rp1_node, NULL, dev);
+	if (err) {
+		dev_err_probe(&pdev->dev, err, "Error populating devicetree\n");
+		goto err_unload_overlay;
+	}
+
+	return 0;
+
+err_unload_overlay:
+	of_overlay_remove(&rp1->ovcs_id);
+err_unregister_interrupts:
+	rp1_unregister_interrupts(pdev);
+err_put_node:
+	if (skip_ovl)
+		of_node_put(rp1_node);
+
+	return err;
+}
+
+static void rp1_remove(struct pci_dev *pdev)
+{
+	struct rp1_dev *rp1 = pci_get_drvdata(pdev);
+	struct device *dev = &pdev->dev;
+
+	of_platform_depopulate(dev);
+	of_overlay_remove(&rp1->ovcs_id);
+	rp1_unregister_interrupts(pdev);
+}
+
+static const struct pci_device_id dev_id_table[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_RPI, PCI_DEVICE_ID_RPI_RP1_C0), },
+	{ }
+};
+MODULE_DEVICE_TABLE(pci, dev_id_table);
+
+static struct pci_driver rp1_driver = {
+	.name		= KBUILD_MODNAME,
+	.id_table	= dev_id_table,
+	.probe		= rp1_probe,
+	.remove		= rp1_remove,
+};
+
+module_pci_driver(rp1_driver);
+
+MODULE_AUTHOR("Phil Elwell <phil@raspberrypi.com>");
+MODULE_AUTHOR("Andrea della Porta <andrea.porta@suse.com>");
+MODULE_DESCRIPTION("RaspberryPi RP1 misc device");
+MODULE_LICENSE("GPL");