--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SG2042 MSI Controller
+ *
+ * Copyright (C) 2024 Sophgo Technology Inc.
+ * Copyright (C) 2024 Chen Wang <unicorn_wang@outlook.com>
+ */
+
+#include <linux/cleanup.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+
+#include "irq-msi-lib.h"
+
+#define SG2042_MAX_MSI_VECTOR 32
+
+struct sg2042_msi_chipdata {
+ void __iomem *reg_clr; // clear reg, see TRM, 10.1.33, GP_INTR0_CLR
+
+ phys_addr_t doorbell_addr; // see TRM, 10.1.32, GP_INTR0_SET
+
+ u32 irq_first; // The vector number that MSIs starts
+ u32 num_irqs; // The number of vectors for MSIs
+
+ DECLARE_BITMAP(msi_map, SG2042_MAX_MSI_VECTOR);
+ struct mutex msi_map_lock; // lock for msi_map
+};
+
+static int sg2042_msi_allocate_hwirq(struct sg2042_msi_chipdata *data, int num_req)
+{
+ int first;
+
+ guard(mutex)(&data->msi_map_lock);
+ first = bitmap_find_free_region(data->msi_map, data->num_irqs,
+ get_count_order(num_req));
+ return first >= 0 ? first : -ENOSPC;
+}
+
+static void sg2042_msi_free_hwirq(struct sg2042_msi_chipdata *data, int hwirq, int num_req)
+{
+ guard(mutex)(&data->msi_map_lock);
+ bitmap_release_region(data->msi_map, hwirq, get_count_order(num_req));
+}
+
+static void sg2042_msi_irq_ack(struct irq_data *d)
+{
+ struct sg2042_msi_chipdata *data = irq_data_get_irq_chip_data(d);
+ int bit_off = d->hwirq;
+
+ writel(1 << bit_off, data->reg_clr);
+
+ irq_chip_ack_parent(d);
+}
+
+static void sg2042_msi_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg)
+{
+ struct sg2042_msi_chipdata *data = irq_data_get_irq_chip_data(d);
+
+ msg->address_hi = upper_32_bits(data->doorbell_addr);
+ msg->address_lo = lower_32_bits(data->doorbell_addr);
+ msg->data = 1 << d->hwirq;
+}
+
+static const struct irq_chip sg2042_msi_middle_irq_chip = {
+ .name = "SG2042 MSI",
+ .irq_ack = sg2042_msi_irq_ack,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+#endif
+ .irq_compose_msi_msg = sg2042_msi_irq_compose_msi_msg,
+};
+
+static int sg2042_msi_parent_domain_alloc(struct irq_domain *domain, unsigned int virq, int hwirq)
+{
+ struct sg2042_msi_chipdata *data = domain->host_data;
+ struct irq_fwspec fwspec;
+ struct irq_data *d;
+ int ret;
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 2;
+ fwspec.param[0] = data->irq_first + hwirq;
+ fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
+ if (ret)
+ return ret;
+
+ d = irq_domain_get_irq_data(domain->parent, virq);
+ return d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING);
+}
+
+static int sg2042_msi_middle_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ struct sg2042_msi_chipdata *data = domain->host_data;
+ int hwirq, err, i;
+
+ hwirq = sg2042_msi_allocate_hwirq(data, nr_irqs);
+ if (hwirq < 0)
+ return hwirq;
+
+ for (i = 0; i < nr_irqs; i++) {
+ err = sg2042_msi_parent_domain_alloc(domain, virq + i, hwirq + i);
+ if (err)
+ goto err_hwirq;
+
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &sg2042_msi_middle_irq_chip, data);
+ }
+
+ return 0;
+
+err_hwirq:
+ sg2042_msi_free_hwirq(data, hwirq, nr_irqs);
+ irq_domain_free_irqs_parent(domain, virq, i);
+
+ return err;
+}
+
+static void sg2042_msi_middle_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+ struct sg2042_msi_chipdata *data = irq_data_get_irq_chip_data(d);
+
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+ sg2042_msi_free_hwirq(data, d->hwirq, nr_irqs);
+}
+
+static const struct irq_domain_ops sg2042_msi_middle_domain_ops = {
+ .alloc = sg2042_msi_middle_domain_alloc,
+ .free = sg2042_msi_middle_domain_free,
+ .select = msi_lib_irq_domain_select,
+};
+
+#define SG2042_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS | \
+ MSI_FLAG_USE_DEF_CHIP_OPS)
+
+#define SG2042_MSI_FLAGS_SUPPORTED MSI_GENERIC_FLAGS_MASK
+
+static const struct msi_parent_ops sg2042_msi_parent_ops = {
+ .required_flags = SG2042_MSI_FLAGS_REQUIRED,
+ .supported_flags = SG2042_MSI_FLAGS_SUPPORTED,
+ .bus_select_mask = MATCH_PCI_MSI,
+ .bus_select_token = DOMAIN_BUS_NEXUS,
+ .prefix = "SG2042-",
+ .init_dev_msi_info = msi_lib_init_dev_msi_info,
+};
+
+static int sg2042_msi_init_domains(struct sg2042_msi_chipdata *data,
+ struct irq_domain *plic_domain, struct device *dev)
+{
+ struct fwnode_handle *fwnode = dev_fwnode(dev);
+ struct irq_domain *middle_domain;
+
+ middle_domain = irq_domain_create_hierarchy(plic_domain, 0, data->num_irqs, fwnode,
+ &sg2042_msi_middle_domain_ops, data);
+ if (!middle_domain) {
+ pr_err("Failed to create the MSI middle domain\n");
+ return -ENOMEM;
+ }
+
+ irq_domain_update_bus_token(middle_domain, DOMAIN_BUS_NEXUS);
+
+ middle_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT;
+ middle_domain->msi_parent_ops = &sg2042_msi_parent_ops;
+
+ return 0;
+}
+
+static int sg2042_msi_probe(struct platform_device *pdev)
+{
+ struct fwnode_reference_args args = { };
+ struct sg2042_msi_chipdata *data;
+ struct device *dev = &pdev->dev;
+ struct irq_domain *plic_domain;
+ struct resource *res;
+ int ret;
+
+ data = devm_kzalloc(dev, sizeof(struct sg2042_msi_chipdata), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->reg_clr = devm_platform_ioremap_resource_byname(pdev, "clr");
+ if (IS_ERR(data->reg_clr)) {
+ dev_err(dev, "Failed to map clear register\n");
+ return PTR_ERR(data->reg_clr);
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "doorbell");
+ if (!res) {
+ dev_err(dev, "Failed get resource from set\n");
+ return -EINVAL;
+ }
+ data->doorbell_addr = res->start;
+
+ ret = fwnode_property_get_reference_args(dev_fwnode(dev), "msi-ranges",
+ "#interrupt-cells", 0, 0, &args);
+ if (ret) {
+ dev_err(dev, "Unable to parse MSI vec base\n");
+ return ret;
+ }
+ fwnode_handle_put(args.fwnode);
+
+ ret = fwnode_property_get_reference_args(dev_fwnode(dev), "msi-ranges", NULL,
+ args.nargs + 1, 0, &args);
+ if (ret) {
+ dev_err(dev, "Unable to parse MSI vec number\n");
+ return ret;
+ }
+
+ plic_domain = irq_find_matching_fwnode(args.fwnode, DOMAIN_BUS_ANY);
+ fwnode_handle_put(args.fwnode);
+ if (!plic_domain) {
+ pr_err("Failed to find the PLIC domain\n");
+ return -ENXIO;
+ }
+
+ data->irq_first = (u32)args.args[0];
+ data->num_irqs = (u32)args.args[args.nargs - 1];
+
+ mutex_init(&data->msi_map_lock);
+
+ return sg2042_msi_init_domains(data, plic_domain, dev);
+}
+
+static const struct of_device_id sg2042_msi_of_match[] = {
+ { .compatible = "sophgo,sg2042-msi" },
+ { }
+};
+
+static struct platform_driver sg2042_msi_driver = {
+ .driver = {
+ .name = "sg2042-msi",
+ .of_match_table = sg2042_msi_of_match,
+ },
+ .probe = sg2042_msi_probe,
+};
+builtin_platform_driver(sg2042_msi_driver);
projects / thirdparty / kernel / linux.git / commitdiff
