--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+
+#define pr_fmt(fmt) "mvebu-sei: " fmt
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/msi.h>
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+
+/* Cause register */
+#define GICP_SECR(idx) (0x0 + ((idx) * 0x4))
+/* Mask register */
+#define GICP_SEMR(idx) (0x20 + ((idx) * 0x4))
+#define GICP_SET_SEI_OFFSET 0x30
+
+#define SEI_IRQ_COUNT_PER_REG 32
+#define SEI_IRQ_REG_COUNT 2
+#define SEI_IRQ_COUNT (SEI_IRQ_COUNT_PER_REG * SEI_IRQ_REG_COUNT)
+#define SEI_IRQ_REG_IDX(irq_id) ((irq_id) / SEI_IRQ_COUNT_PER_REG)
+#define SEI_IRQ_REG_BIT(irq_id) ((irq_id) % SEI_IRQ_COUNT_PER_REG)
+
+struct mvebu_sei_interrupt_range {
+ u32 first;
+ u32 size;
+};
+
+struct mvebu_sei_caps {
+ struct mvebu_sei_interrupt_range ap_range;
+ struct mvebu_sei_interrupt_range cp_range;
+};
+
+struct mvebu_sei {
+ struct device *dev;
+ void __iomem *base;
+ struct resource *res;
+ struct irq_domain *sei_domain;
+ struct irq_domain *ap_domain;
+ struct irq_domain *cp_domain;
+ const struct mvebu_sei_caps *caps;
+
+ /* Lock on MSI allocations/releases */
+ struct mutex cp_msi_lock;
+ DECLARE_BITMAP(cp_msi_bitmap, SEI_IRQ_COUNT);
+
+ /* Lock on IRQ masking register */
+ raw_spinlock_t mask_lock;
+};
+
+static void mvebu_sei_ack_irq(struct irq_data *d)
+{
+ struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
+ u32 reg_idx = SEI_IRQ_REG_IDX(d->hwirq);
+
+ writel_relaxed(BIT(SEI_IRQ_REG_BIT(d->hwirq)),
+ sei->base + GICP_SECR(reg_idx));
+}
+
+static void mvebu_sei_mask_irq(struct irq_data *d)
+{
+ struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
+ u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq);
+ unsigned long flags;
+
+ /* 1 disables the interrupt */
+ raw_spin_lock_irqsave(&sei->mask_lock, flags);
+ reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx));
+ reg |= BIT(SEI_IRQ_REG_BIT(d->hwirq));
+ writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx));
+ raw_spin_unlock_irqrestore(&sei->mask_lock, flags);
+}
+
+static void mvebu_sei_unmask_irq(struct irq_data *d)
+{
+ struct mvebu_sei *sei = irq_data_get_irq_chip_data(d);
+ u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq);
+ unsigned long flags;
+
+ /* 0 enables the interrupt */
+ raw_spin_lock_irqsave(&sei->mask_lock, flags);
+ reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx));
+ reg &= ~BIT(SEI_IRQ_REG_BIT(d->hwirq));
+ writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx));
+ raw_spin_unlock_irqrestore(&sei->mask_lock, flags);
+}
+
+static int mvebu_sei_set_affinity(struct irq_data *d,
+ const struct cpumask *mask_val,
+ bool force)
+{
+ return -EINVAL;
+}
+
+static int mvebu_sei_set_irqchip_state(struct irq_data *d,
+ enum irqchip_irq_state which,
+ bool state)
+{
+ /* We can only clear the pending state by acking the interrupt */
+ if (which != IRQCHIP_STATE_PENDING || state)
+ return -EINVAL;
+
+ mvebu_sei_ack_irq(d);
+ return 0;
+}
+
+static struct irq_chip mvebu_sei_irq_chip = {
+ .name = "SEI",
+ .irq_ack = mvebu_sei_ack_irq,
+ .irq_mask = mvebu_sei_mask_irq,
+ .irq_unmask = mvebu_sei_unmask_irq,
+ .irq_set_affinity = mvebu_sei_set_affinity,
+ .irq_set_irqchip_state = mvebu_sei_set_irqchip_state,
+};
+
+static int mvebu_sei_ap_set_type(struct irq_data *data, unsigned int type)
+{
+ if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_HIGH)
+ return -EINVAL;
+
+ return 0;
+}
+
+static struct irq_chip mvebu_sei_ap_irq_chip = {
+ .name = "AP SEI",
+ .irq_ack = irq_chip_ack_parent,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .irq_set_type = mvebu_sei_ap_set_type,
+};
+
+static void mvebu_sei_cp_compose_msi_msg(struct irq_data *data,
+ struct msi_msg *msg)
+{
+ struct mvebu_sei *sei = data->chip_data;
+ phys_addr_t set = sei->res->start + GICP_SET_SEI_OFFSET;
+
+ msg->data = data->hwirq + sei->caps->cp_range.first;
+ msg->address_lo = lower_32_bits(set);
+ msg->address_hi = upper_32_bits(set);
+}
+
+static int mvebu_sei_cp_set_type(struct irq_data *data, unsigned int type)
+{
+ if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_EDGE_RISING)
+ return -EINVAL;
+
+ return 0;
+}
+
+static struct irq_chip mvebu_sei_cp_irq_chip = {
+ .name = "CP SEI",
+ .irq_ack = irq_chip_ack_parent,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .irq_set_type = mvebu_sei_cp_set_type,
+ .irq_compose_msi_msg = mvebu_sei_cp_compose_msi_msg,
+};
+
+static int mvebu_sei_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct mvebu_sei *sei = domain->host_data;
+ struct irq_fwspec *fwspec = arg;
+
+ /* Not much to do, just setup the irqdata */
+ irq_domain_set_hwirq_and_chip(domain, virq, fwspec->param[0],
+ &mvebu_sei_irq_chip, sei);
+
+ return 0;
+}
+
+static void mvebu_sei_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ int i;
+
+ for (i = 0; i < nr_irqs; i++) {
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
+ irq_set_handler(virq + i, NULL);
+ irq_domain_reset_irq_data(d);
+ }
+}
+
+static const struct irq_domain_ops mvebu_sei_domain_ops = {
+ .alloc = mvebu_sei_domain_alloc,
+ .free = mvebu_sei_domain_free,
+};
+
+static int mvebu_sei_ap_translate(struct irq_domain *domain,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ *hwirq = fwspec->param[0];
+ *type = IRQ_TYPE_LEVEL_HIGH;
+
+ return 0;
+}
+
+static int mvebu_sei_ap_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct mvebu_sei *sei = domain->host_data;
+ struct irq_fwspec fwspec;
+ unsigned long hwirq;
+ unsigned int type;
+ int err;
+
+ mvebu_sei_ap_translate(domain, arg, &hwirq, &type);
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 1;
+ fwspec.param[0] = hwirq + sei->caps->ap_range.first;
+
+ err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
+ if (err)
+ return err;
+
+ irq_domain_set_info(domain, virq, hwirq,
+ &mvebu_sei_ap_irq_chip, sei,
+ handle_level_irq, NULL, NULL);
+ irq_set_probe(virq);
+
+ return 0;
+}
+
+static const struct irq_domain_ops mvebu_sei_ap_domain_ops = {
+ .translate = mvebu_sei_ap_translate,
+ .alloc = mvebu_sei_ap_alloc,
+ .free = irq_domain_free_irqs_parent,
+};
+
+static void mvebu_sei_cp_release_irq(struct mvebu_sei *sei, unsigned long hwirq)
+{
+ mutex_lock(&sei->cp_msi_lock);
+ clear_bit(hwirq, sei->cp_msi_bitmap);
+ mutex_unlock(&sei->cp_msi_lock);
+}
+
+static int mvebu_sei_cp_domain_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *args)
+{
+ struct mvebu_sei *sei = domain->host_data;
+ struct irq_fwspec fwspec;
+ unsigned long hwirq;
+ int ret;
+
+ /* The software only supports single allocations for now */
+ if (nr_irqs != 1)
+ return -ENOTSUPP;
+
+ mutex_lock(&sei->cp_msi_lock);
+ hwirq = find_first_zero_bit(sei->cp_msi_bitmap,
+ sei->caps->cp_range.size);
+ if (hwirq < sei->caps->cp_range.size)
+ set_bit(hwirq, sei->cp_msi_bitmap);
+ mutex_unlock(&sei->cp_msi_lock);
+
+ if (hwirq == sei->caps->cp_range.size)
+ return -ENOSPC;
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 1;
+ fwspec.param[0] = hwirq + sei->caps->cp_range.first;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
+ if (ret)
+ goto free_irq;
+
+ irq_domain_set_info(domain, virq, hwirq,
+ &mvebu_sei_cp_irq_chip, sei,
+ handle_edge_irq, NULL, NULL);
+
+ return 0;
+
+free_irq:
+ mvebu_sei_cp_release_irq(sei, hwirq);
+ return ret;
+}
+
+static void mvebu_sei_cp_domain_free(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct mvebu_sei *sei = domain->host_data;
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+
+ if (nr_irqs != 1 || d->hwirq >= sei->caps->cp_range.size) {
+ dev_err(sei->dev, "Invalid hwirq %lu\n", d->hwirq);
+ return;
+ }
+
+ mvebu_sei_cp_release_irq(sei, d->hwirq);
+ irq_domain_free_irqs_parent(domain, virq, 1);
+}
+
+static const struct irq_domain_ops mvebu_sei_cp_domain_ops = {
+ .alloc = mvebu_sei_cp_domain_alloc,
+ .free = mvebu_sei_cp_domain_free,
+};
+
+static struct irq_chip mvebu_sei_msi_irq_chip = {
+ .name = "SEI pMSI",
+ .irq_ack = irq_chip_ack_parent,
+ .irq_set_type = irq_chip_set_type_parent,
+};
+
+static struct msi_domain_ops mvebu_sei_msi_ops = {
+};
+
+static struct msi_domain_info mvebu_sei_msi_domain_info = {
+ .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS,
+ .ops = &mvebu_sei_msi_ops,
+ .chip = &mvebu_sei_msi_irq_chip,
+};
+
+static void mvebu_sei_handle_cascade_irq(struct irq_desc *desc)
+{
+ struct mvebu_sei *sei = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 idx;
+
+ chained_irq_enter(chip, desc);
+
+ for (idx = 0; idx < SEI_IRQ_REG_COUNT; idx++) {
+ unsigned long irqmap;
+ int bit;
+
+ irqmap = readl_relaxed(sei->base + GICP_SECR(idx));
+ for_each_set_bit(bit, &irqmap, SEI_IRQ_COUNT_PER_REG) {
+ unsigned long hwirq;
+ unsigned int virq;
+
+ hwirq = idx * SEI_IRQ_COUNT_PER_REG + bit;
+ virq = irq_find_mapping(sei->sei_domain, hwirq);
+ if (likely(virq)) {
+ generic_handle_irq(virq);
+ continue;
+ }
+
+ dev_warn(sei->dev,
+ "Spurious IRQ detected (hwirq %lu)\n", hwirq);
+ }
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+static void mvebu_sei_reset(struct mvebu_sei *sei)
+{
+ u32 reg_idx;
+
+ /* Clear IRQ cause registers, mask all interrupts */
+ for (reg_idx = 0; reg_idx < SEI_IRQ_REG_COUNT; reg_idx++) {
+ writel_relaxed(0xFFFFFFFF, sei->base + GICP_SECR(reg_idx));
+ writel_relaxed(0xFFFFFFFF, sei->base + GICP_SEMR(reg_idx));
+ }
+}
+
+static int mvebu_sei_probe(struct platform_device *pdev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct irq_domain *plat_domain;
+ struct mvebu_sei *sei;
+ u32 parent_irq;
+ int ret;
+
+ sei = devm_kzalloc(&pdev->dev, sizeof(*sei), GFP_KERNEL);
+ if (!sei)
+ return -ENOMEM;
+
+ sei->dev = &pdev->dev;
+
+ mutex_init(&sei->cp_msi_lock);
+ raw_spin_lock_init(&sei->mask_lock);
+
+ sei->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sei->base = devm_ioremap_resource(sei->dev, sei->res);
+ if (!sei->base) {
+ dev_err(sei->dev, "Failed to remap SEI resource\n");
+ return -ENODEV;
+ }
+
+ /* Retrieve the SEI capabilities with the interrupt ranges */
+ sei->caps = of_device_get_match_data(&pdev->dev);
+ if (!sei->caps) {
+ dev_err(sei->dev,
+ "Could not retrieve controller capabilities\n");
+ return -EINVAL;
+ }
+
+ /*
+ * Reserve the single (top-level) parent SPI IRQ from which all the
+ * interrupts handled by this driver will be signaled.
+ */
+ parent_irq = irq_of_parse_and_map(node, 0);
+ if (parent_irq <= 0) {
+ dev_err(sei->dev, "Failed to retrieve top-level SPI IRQ\n");
+ return -ENODEV;
+ }
+
+ /* Create the root SEI domain */
+ sei->sei_domain = irq_domain_create_linear(of_node_to_fwnode(node),
+ (sei->caps->ap_range.size +
+ sei->caps->cp_range.size),
+ &mvebu_sei_domain_ops,
+ sei);
+ if (!sei->sei_domain) {
+ dev_err(sei->dev, "Failed to create SEI IRQ domain\n");
+ ret = -ENOMEM;
+ goto dispose_irq;
+ }
+
+ irq_domain_update_bus_token(sei->sei_domain, DOMAIN_BUS_NEXUS);
+
+ /* Create the 'wired' domain */
+ sei->ap_domain = irq_domain_create_hierarchy(sei->sei_domain, 0,
+ sei->caps->ap_range.size,
+ of_node_to_fwnode(node),
+ &mvebu_sei_ap_domain_ops,
+ sei);
+ if (!sei->ap_domain) {
+ dev_err(sei->dev, "Failed to create AP IRQ domain\n");
+ ret = -ENOMEM;
+ goto remove_sei_domain;
+ }
+
+ irq_domain_update_bus_token(sei->ap_domain, DOMAIN_BUS_WIRED);
+
+ /* Create the 'MSI' domain */
+ sei->cp_domain = irq_domain_create_hierarchy(sei->sei_domain, 0,
+ sei->caps->cp_range.size,
+ of_node_to_fwnode(node),
+ &mvebu_sei_cp_domain_ops,
+ sei);
+ if (!sei->cp_domain) {
+ pr_err("Failed to create CPs IRQ domain\n");
+ ret = -ENOMEM;
+ goto remove_ap_domain;
+ }
+
+ irq_domain_update_bus_token(sei->cp_domain, DOMAIN_BUS_GENERIC_MSI);
+
+ plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node),
+ &mvebu_sei_msi_domain_info,
+ sei->cp_domain);
+ if (!plat_domain) {
+ pr_err("Failed to create CPs MSI domain\n");
+ ret = -ENOMEM;
+ goto remove_cp_domain;
+ }
+
+ mvebu_sei_reset(sei);
+
+ irq_set_chained_handler_and_data(parent_irq,
+ mvebu_sei_handle_cascade_irq,
+ sei);
+
+ return 0;
+
+remove_cp_domain:
+ irq_domain_remove(sei->cp_domain);
+remove_ap_domain:
+ irq_domain_remove(sei->ap_domain);
+remove_sei_domain:
+ irq_domain_remove(sei->sei_domain);
+dispose_irq:
+ irq_dispose_mapping(parent_irq);
+
+ return ret;
+}
+
+struct mvebu_sei_caps mvebu_sei_ap806_caps = {
+ .ap_range = {
+ .first = 0,
+ .size = 21,
+ },
+ .cp_range = {
+ .first = 21,
+ .size = 43,
+ },
+};
+
+static const struct of_device_id mvebu_sei_of_match[] = {
+ {
+ .compatible = "marvell,ap806-sei",
+ .data = &mvebu_sei_ap806_caps,
+ },
+ {},
+};
+
+static struct platform_driver mvebu_sei_driver = {
+ .probe = mvebu_sei_probe,
+ .driver = {
+ .name = "mvebu-sei",
+ .of_match_table = mvebu_sei_of_match,
+ },
+};
+builtin_platform_driver(mvebu_sei_driver);