[PATCH v2 2/3] irqchip: Add the Sophgo SG2042 MSI interrupt controller

Chen Wang
2024-12-09T07:12:16Z

From: Chen Wang <unicorn_wang@outlook.com>

Add driver for Sophgo SG2042 MSI interrupt controller.

Signed-off-by: Chen Wang <unicorn_wang@outlook.com>
---
drivers/irqchip/Kconfig | 12 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-sg2042-msi.c | 285 +++++++++++++++++++++++++++++++
3 files changed, 298 insertions(+)
create mode 100644 drivers/irqchip/irq-sg2042-msi.c

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 9bee02db1643..161fb5df857f 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -749,6 +749,18 @@ config MCHP_EIC
help
Support for Microchip External Interrupt Controller.

+config SOPHGO_SG2042_MSI
+ bool "Sophgo SG2042 MSI Controller"
+ depends on ARCH_SOPHGO || COMPILE_TEST
+ depends on PCI
+ select IRQ_DOMAIN_HIERARCHY
+ select IRQ_MSI_LIB
+ select PCI_MSI
+ help
+ Support for the Sophgo SG2042 MSI Controller.
+ This on-chip interrupt controller enables MSI sources to be
+ routed to the primary PLIC controller on SoC.
+
config SUNPLUS_SP7021_INTC
bool "Sunplus SP7021 interrupt controller" if COMPILE_TEST
default SOC_SP7021
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 25e9ad29b8c4..dd60e597491d 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -128,4 +128,5 @@ obj-$(CONFIG_WPCM450_AIC) += irq-wpcm450-aic.o
obj-$(CONFIG_IRQ_IDT3243X) += irq-idt3243x.o
obj-$(CONFIG_APPLE_AIC) += irq-apple-aic.o
obj-$(CONFIG_MCHP_EIC) += irq-mchp-eic.o
+obj-$(CONFIG_SOPHGO_SG2042_MSI) += irq-sg2042-msi.o
obj-$(CONFIG_SUNPLUS_SP7021_INTC) += irq-sp7021-intc.o
diff --git a/drivers/irqchip/irq-sg2042-msi.c b/drivers/irqchip/irq-sg2042-msi.c
new file mode 100644
index 000000000000..495ee2b45eb2
--- /dev/null
+++ b/drivers/irqchip/irq-sg2042-msi.c
@@ -0,0 +1,285 @@
+// 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/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "irq-msi-lib.h"
+
+#define SG2042_VECTOR_MIN 64
+#define SG2042_VECTOR_MAX 95
+
+struct sg2042_msi_data {
+ void __iomem *reg_clr; // clear reg, see TRM, 10.1.33, GP_INTR0_CLR
+
+ u64 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
+
+ unsigned long *msi_map;
+ struct mutex msi_map_lock; // lock for msi_map
+};
+
+static int sg2042_msi_allocate_hwirq(struct sg2042_msi_data *priv, int num_req)
+{
+ int first;
+
+ guard(mutex)(&priv->msi_map_lock);
+ first = bitmap_find_free_region(priv->msi_map, priv->num_irqs,
+ get_count_order(num_req));
+ return first >= 0 ? priv->irq_first + first : -ENOSPC;
+}
+
+static void sg2042_msi_free_hwirq(struct sg2042_msi_data *priv,
+ int hwirq, int num_req)
+{
+ int first = hwirq - priv->irq_first;
+
+ guard(mutex)(&priv->msi_map_lock);
+ bitmap_release_region(priv->msi_map, first, get_count_order(num_req));
+}
+
+static void sg2042_msi_irq_ack(struct irq_data *d)
+{
+ struct sg2042_msi_data *data = irq_data_get_irq_chip_data(d);
+ int bit_off = d->hwirq - data->irq_first;
+
+ writel(1 << bit_off, (unsigned int *)data->reg_clr);
+
+ irq_chip_ack_parent(d);
+}
+
+static void sg2042_msi_irq_compose_msi_msg(struct irq_data *data,
+ struct msi_msg *msg)
+{
+ struct sg2042_msi_data *priv = irq_data_get_irq_chip_data(data);
+
+ msg->address_hi = upper_32_bits(priv->doorbell_addr);
+ msg->address_lo = lower_32_bits(priv->doorbell_addr);
+ msg->data = 1 << (data->hwirq - priv->irq_first);
+
+ pr_debug("%s hwirq[%ld]: address_hi[%#x], address_lo[%#x], data[%#x]\n",
+ __func__, data->hwirq, msg->address_hi, msg->address_lo, msg->data);
+}
+
+static 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 irq_fwspec fwspec;
+ struct irq_data *d;
+ int ret;
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 2;
+ fwspec.param[0] = 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_data *priv = domain->host_data;
+ int hwirq, err, i;
+
+ hwirq = sg2042_msi_allocate_hwirq(priv, 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;
+
+ pr_debug("%s: virq[%d], hwirq[%d]\n", __func__, virq + i, hwirq + i);
+
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &sg2042_msi_middle_irq_chip, priv);
+ }
+
+ return 0;
+
+err_hwirq:
+ sg2042_msi_free_hwirq(priv, 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_data *priv = irq_data_get_irq_chip_data(d);
+
+ irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+ sg2042_msi_free_hwirq(priv, 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 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_data *priv,
+ struct device_node *node)
+{
+ struct fwnode_handle *fwnode = of_node_to_fwnode(node);
+ struct irq_domain *plic_domain, *middle_domain;
+ struct device_node *plic_node;
+
+ if (!of_find_property(node, "interrupt-parent", NULL)) {
+ pr_err("Can't find interrupt-parent!\n");
+ return -EINVAL;
+ }
+
+ plic_node = of_irq_find_parent(node);
+ if (!plic_node) {
+ pr_err("Failed to find the PLIC node!\n");
+ return -ENXIO;
+ }
+
+ plic_domain = irq_find_host(plic_node);
+ of_node_put(plic_node);
+ if (!plic_domain) {
+ pr_err("Failed to find the PLIC domain\n");
+ return -ENXIO;
+ }
+
+ middle_domain = irq_domain_create_hierarchy(plic_domain, 0, priv->num_irqs,
+ fwnode,
+ &sg2042_msi_middle_domain_ops,
+ priv);
+ 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 of_phandle_args args = {};
+ struct sg2042_msi_data *data;
+ int ret;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(struct sg2042_msi_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->reg_clr = devm_platform_ioremap_resource_byname(pdev, "clr");
+ if (IS_ERR(data->reg_clr)) {
+ dev_err(&pdev->dev, "Failed to map clear register\n");
+ return PTR_ERR(data->reg_clr);
+ }
+
+ if (of_property_read_u64(pdev->dev.of_node, "sophgo,msi-doorbell-addr",
+ &data->doorbell_addr)) {
+ dev_err(&pdev->dev, "Unable to parse MSI doorbell addr\n");
+ return -EINVAL;
+ }
+
+ ret = of_parse_phandle_with_args(pdev->dev.of_node, "msi-ranges",
+ "#interrupt-cells", 0, &args);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to parse MSI vec base\n");
+ return ret;
+ }
+ data->irq_first = (u32)args.args[0];
+
+ ret = of_property_read_u32_index(pdev->dev.of_node, "msi-ranges",
+ args.args_count + 1, &data->num_irqs);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to parse MSI vec number\n");
+ return ret;
+ }
+
+ if (data->irq_first < SG2042_VECTOR_MIN ||
+ (data->irq_first + data->num_irqs - 1) > SG2042_VECTOR_MAX) {
+ dev_err(&pdev->dev, "msi-ranges is incorrect!\n");
+ return -EINVAL;
+ }
+
+ mutex_init(&data->msi_map_lock);
+
+ data->msi_map = bitmap_zalloc(data->num_irqs, GFP_KERNEL);
+ if (!data->msi_map)
+ return -ENOMEM;
+
+ ret = sg2042_msi_init_domains(data, pdev->dev.of_node);
+ if (ret)
+ bitmap_free(data->msi_map);
+
+ return ret;
+}
+
+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 = of_match_ptr(sg2042_msi_of_match),
+ },
+ .probe = sg2042_msi_probe,
+};
+builtin_platform_driver(sg2042_msi_driver);
--
2.34.1