[PATCH v7 09/14] irqchip: ti-sci-intr: Add support for Interrupt Router driver

From: Lokesh Vutla
Date: Sat Apr 20 2019 - 06:11:50 EST


Texas Instruments' K3 generation SoCs has an IP Interrupt Router
that does allows for redirection of input interrupts to host
interrupt controller. Interrupt Router inputs are either from a
peripheral or from an Interrupt Aggregator which is another
interrupt controller.

Configuration of the interrupt router registers can only be done by
a system co-processor and the driver needs to send a message to this
co processor over TISCI protocol.

Add support for Interrupt Router driver over TISCI protocol.

Signed-off-by: Lokesh Vutla <lokeshvutla@xxxxxx>
---
Changes since v6:
- Arranged header files in alphabetical order
- Dropped few unused members in ti_sci_intr_irq_domain structure

MAINTAINERS | 1 +
drivers/irqchip/Kconfig | 11 ++
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-ti-sci-intr.c | 285 ++++++++++++++++++++++++++++++
4 files changed, 298 insertions(+)
create mode 100644 drivers/irqchip/irq-ti-sci-intr.c

diff --git a/MAINTAINERS b/MAINTAINERS
index b40762656a6d..63851f106b5c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15350,6 +15350,7 @@ F: Documentation/devicetree/bindings/clock/ti,sci-clk.txt
F: drivers/clk/keystone/sci-clk.c
F: drivers/reset/reset-ti-sci.c
F: Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
+F: drivers/irqchip/irq-ti-sci-intr.c

Texas Instruments ASoC drivers
M: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 5438abb1baba..4f84e7902626 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -425,6 +425,17 @@ config LS1X_IRQ
help
Support for the Loongson-1 platform Interrupt Controller.

+config TI_SCI_INTR_IRQCHIP
+ bool
+ depends on TI_SCI_PROTOCOL
+ select IRQ_DOMAIN
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ This enables the irqchip driver support for K3 Interrupt router
+ over TI System Control Interface available on some new TI's SoCs.
+ If you wish to use interrupt router irq resources managed by the
+ TI System Controller, say Y here. Otherwise, say N.
+
endmenu

config SIFIVE_PLIC
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 85972ae1bd7f..fa5c865788b5 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -97,3 +97,4 @@ obj-$(CONFIG_SIFIVE_PLIC) += irq-sifive-plic.o
obj-$(CONFIG_IMX_IRQSTEER) += irq-imx-irqsteer.o
obj-$(CONFIG_MADERA_IRQ) += irq-madera.o
obj-$(CONFIG_LS1X_IRQ) += irq-ls1x.o
+obj-$(CONFIG_TI_SCI_INTR_IRQCHIP) += irq-ti-sci-intr.o
diff --git a/drivers/irqchip/irq-ti-sci-intr.c b/drivers/irqchip/irq-ti-sci-intr.c
new file mode 100644
index 000000000000..354b9d53798d
--- /dev/null
+++ b/drivers/irqchip/irq-ti-sci-intr.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Texas Instruments' K3 Interrupt Router irqchip driver
+ *
+ * Copyright (C) 2018-2019 Texas Instruments Incorporated - http://www.ti.com/
+ * Lokesh Vutla <lokeshvutla@xxxxxx>
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+
+#define TI_SCI_DEV_ID_MASK 0xffff
+#define TI_SCI_DEV_ID_SHIFT 16
+#define TI_SCI_IRQ_ID_MASK 0xffff
+#define TI_SCI_IRQ_ID_SHIFT 0
+#define HWIRQ_TO_DEVID(hwirq) (((hwirq) >> (TI_SCI_DEV_ID_SHIFT)) & \
+ (TI_SCI_DEV_ID_MASK))
+#define HWIRQ_TO_IRQID(hwirq) ((hwirq) & (TI_SCI_IRQ_ID_MASK))
+#define TO_HWIRQ(dev, index) ((((dev) & TI_SCI_DEV_ID_MASK) << \
+ TI_SCI_DEV_ID_SHIFT) | \
+ ((index) & TI_SCI_IRQ_ID_MASK))
+
+/**
+ * struct ti_sci_intr_irq_domain - Structure representing a TISCI based
+ * Interrupt Router IRQ domain.
+ * @sci: Pointer to TISCI handle
+ * @dst_irq: TISCI resource pointer representing GIC irq controller.
+ * @dst_id: TISCI device ID of the GIC irq controller.
+ * @type: Specifies the trigger type supported by this Interrupt Router
+ */
+struct ti_sci_intr_irq_domain {
+ const struct ti_sci_handle *sci;
+ struct ti_sci_resource *dst_irq;
+ u32 dst_id;
+ u32 type;
+};
+
+static struct irq_chip ti_sci_intr_irq_chip = {
+ .name = "INTR",
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_set_type = irq_chip_set_type_parent,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+};
+
+/**
+ * ti_sci_intr_irq_domain_translate() - Retrieve hwirq and type from
+ * IRQ firmware specific handler.
+ * @domain: Pointer to IRQ domain
+ * @fwspec: Pointer to IRQ specific firmware structure
+ * @hwirq: IRQ number identified by hardware
+ * @type: IRQ type
+ *
+ * Return 0 if all went ok else appropriate error.
+ */
+static int ti_sci_intr_irq_domain_translate(struct irq_domain *domain,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ struct ti_sci_intr_irq_domain *intr = domain->host_data;
+
+ if (fwspec->param_count != 3)
+ return -EINVAL;
+
+ *hwirq = TO_HWIRQ(fwspec->param[0], fwspec->param[1]);
+ *type = intr->type;
+
+ /* Third parameter can be either 0 or 1 */
+ if (fwspec->param[2] != 0 && fwspec->param[2] != 1)
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * ti_sci_intr_irq_domain_free() - Free the specified IRQs from the domain.
+ * @domain: Domain to which the irqs belong
+ * @virq: Linux virtual IRQ to be freed.
+ * @nr_irqs: Number of continuous irqs to be freed
+ */
+static void ti_sci_intr_irq_domain_free(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs)
+{
+ struct ti_sci_intr_irq_domain *intr = domain->host_data;
+ struct irq_data *data, *parent_data;
+ u16 dev_id, irq_index;
+ u8 flags;
+
+ parent_data = irq_domain_get_irq_data(domain->parent, virq);
+ data = irq_domain_get_irq_data(domain, virq);
+ flags = (uintptr_t)irq_data_get_irq_chip_data(data);
+ irq_index = HWIRQ_TO_IRQID(data->hwirq);
+ dev_id = HWIRQ_TO_DEVID(data->hwirq);
+
+ intr->sci->ops.rm_irq_ops.free_irq(intr->sci, dev_id, irq_index,
+ intr->dst_id, parent_data->hwirq,
+ flags);
+ ti_sci_release_resource(intr->dst_irq, parent_data->hwirq);
+ irq_domain_free_irqs_parent(domain, virq, 1);
+ irq_domain_reset_irq_data(data);
+}
+
+/**
+ * ti_sci_intr_alloc_gic_irq() - Allocate GIC specific IRQ
+ * @domain: Pointer to the interrupt router IRQ domain
+ * @virq: Corresponding Linux virtual IRQ number
+ * @hwirq: Corresponding hwirq for the IRQ within this IRQ domain
+ * @flags: Corresponding flags to the IRQ
+ *
+ * Returns 0 if all went well else appropriate error pointer.
+ */
+static int ti_sci_intr_alloc_gic_irq(struct irq_domain *domain,
+ unsigned int virq, u32 hwirq, u8 flags)
+{
+ struct ti_sci_intr_irq_domain *intr = domain->host_data;
+ struct irq_fwspec fwspec;
+ u16 dev_id, irq_index;
+ u16 dst_irq;
+ int err;
+
+ dev_id = HWIRQ_TO_DEVID(hwirq);
+ irq_index = HWIRQ_TO_IRQID(hwirq);
+
+ dst_irq = ti_sci_get_free_resource(intr->dst_irq);
+ if (dst_irq == TI_SCI_RESOURCE_NULL)
+ return -EINVAL;
+
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 3;
+ fwspec.param[0] = 0; /* SPI */
+ fwspec.param[1] = dst_irq - 32; /* SPI offset */
+ fwspec.param[2] = intr->type;
+
+ err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
+ if (err)
+ goto err_irqs;
+
+ err = intr->sci->ops.rm_irq_ops.set_irq(intr->sci, dev_id, irq_index,
+ intr->dst_id, dst_irq, flags);
+ if (err)
+ goto err_msg;
+
+ return 0;
+
+err_msg:
+ irq_domain_free_irqs_parent(domain, virq, 1);
+err_irqs:
+ ti_sci_release_resource(intr->dst_irq, dst_irq);
+ return err;
+}
+
+/**
+ * ti_sci_intr_irq_domain_alloc() - Allocate Interrupt router IRQs
+ * @domain: Point to the interrupt router IRQ domain
+ * @virq: Corresponding Linux virtual IRQ number
+ * @nr_irqs: Continuous irqs to be allocated
+ * @data: Pointer to firmware specifier
+ *
+ * Return 0 if all went well else appropriate error value.
+ */
+static int ti_sci_intr_irq_domain_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *data)
+{
+ struct irq_fwspec *fwspec = data;
+ unsigned long hwirq;
+ unsigned int flags;
+ int err;
+
+ err = ti_sci_intr_irq_domain_translate(domain, fwspec, &hwirq, &flags);
+ if (err)
+ return err;
+
+ flags = fwspec->param[2];
+ err = ti_sci_intr_alloc_gic_irq(domain, virq, hwirq, flags);
+ if (err)
+ return err;
+
+ irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &ti_sci_intr_irq_chip,
+ (void *)(uintptr_t)flags);
+
+ return 0;
+}
+
+static const struct irq_domain_ops ti_sci_intr_irq_domain_ops = {
+ .free = ti_sci_intr_irq_domain_free,
+ .alloc = ti_sci_intr_irq_domain_alloc,
+ .translate = ti_sci_intr_irq_domain_translate,
+};
+
+static int ti_sci_intr_irq_domain_probe(struct platform_device *pdev)
+{
+ struct irq_domain *parent_domain, *domain;
+ struct ti_sci_intr_irq_domain *intr;
+ struct device_node *parent_node;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ parent_node = of_irq_find_parent(dev_of_node(dev));
+ if (!parent_node) {
+ dev_err(dev, "Failed to get IRQ parent node\n");
+ return -ENODEV;
+ }
+
+ parent_domain = irq_find_host(parent_node);
+ if (!parent_domain) {
+ dev_err(dev, "Failed to find IRQ parent domain\n");
+ return -ENODEV;
+ }
+
+ intr = devm_kzalloc(dev, sizeof(*intr), GFP_KERNEL);
+ if (!intr)
+ return -ENOMEM;
+
+ ret = of_property_read_u32(dev_of_node(dev), "ti,intr-trigger-type",
+ &intr->type);
+ if (ret) {
+ dev_err(dev, "missing ti,intr-trigger-type property\n");
+ return -EINVAL;
+ }
+
+ intr->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
+ if (IS_ERR(intr->sci)) {
+ ret = PTR_ERR(intr->sci);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "ti,sci read fail %d\n", ret);
+ intr->sci = NULL;
+ return ret;
+ }
+
+ ret = of_property_read_u32(dev_of_node(dev), "ti,sci-dst-id",
+ &intr->dst_id);
+ if (ret) {
+ dev_err(dev, "missing 'ti,sci-dst-id' property\n");
+ return -EINVAL;
+ }
+
+ intr->dst_irq = devm_ti_sci_get_of_resource(intr->sci, dev,
+ intr->dst_id,
+ "ti,sci-rm-range-girq");
+ if (IS_ERR(intr->dst_irq)) {
+ dev_err(dev, "Destination irq resource allocation failed\n");
+ return PTR_ERR(intr->dst_irq);
+ }
+
+ domain = irq_domain_add_hierarchy(parent_domain, 0, 0, dev_of_node(dev),
+ &ti_sci_intr_irq_domain_ops, intr);
+ if (!domain) {
+ dev_err(dev, "Failed to allocate IRQ domain\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id ti_sci_intr_irq_domain_of_match[] = {
+ { .compatible = "ti,sci-intr", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_sci_intr_irq_domain_of_match);
+
+static struct platform_driver ti_sci_intr_irq_domain_driver = {
+ .probe = ti_sci_intr_irq_domain_probe,
+ .driver = {
+ .name = "ti-sci-intr",
+ .of_match_table = ti_sci_intr_irq_domain_of_match,
+ },
+};
+module_platform_driver(ti_sci_intr_irq_domain_driver);
+
+MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ticom>");
+MODULE_DESCRIPTION("K3 Interrupt Router driver over TI SCI protocol");
+MODULE_LICENSE("GPL v2");
--
2.21.0