Texas Instruments' K3 generation SoCs has an IP Interrupt Aggregator
which is an interrupt controller that does the following:
- Converts events to interrupts that can be understood by
  an interrupt router.
- Allows for multiplexing of events to interrupts.

Configuration of the interrupt aggregator 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 Aggregator driver with 2 IRQ Domains:
- INTA MSI domain that interfaces the devices using which interrupts can be
  allocated dynamically.
- INTA domain that is parent to the MSI domain that manages the interrupt
  resources.

Signed-off-by: Lokesh Vutla <lokeshvu...@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfal...@ti.com>
---
Changes since v4:
- Allocate the INTA output interrupts during probe.

 MAINTAINERS                       |   1 +
 drivers/irqchip/Kconfig           |  12 +
 drivers/irqchip/Makefile          |   1 +
 drivers/irqchip/irq-ti-sci-inta.c | 531 ++++++++++++++++++++++++++++++
 4 files changed, 545 insertions(+)
 create mode 100644 drivers/irqchip/irq-ti-sci-inta.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 970c732b7158..44a3392239d9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15069,6 +15069,7 @@ F:      
Documentation/devicetree/bindings/interrupt-controller/ti,sci-inta.txt
 F:     drivers/irqchip/irq-ti-sci-intr.c
 F:     drivers/irqchip/irq-ti-sci-common.c
 F:     drivers/irqchip/irq-ti-sci-common.h
+F:     drivers/irqchip/irq-ti-sci-inta.c
 
 Texas Instruments ASoC drivers
 M:     Peter Ujfalusi <peter.ujfal...@ti.com>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a8d9bed0254b..d16fd39408ad 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -417,6 +417,18 @@ config TI_SCI_INTR_IRQCHIP
          If you wish to use interrupt router irq resources managed by the
          TI System Controller, say Y here. Otherwise, say N.
 
+config TI_SCI_INTA_IRQCHIP
+       bool
+       depends on TI_SCI_PROTOCOL && ARCH_K3
+       select IRQ_DOMAIN
+       select IRQ_DOMAIN_HIERARCHY
+       select K3_INTA_MSI_DOMAIN
+       help
+         This enables the irqchip driver support for K3 Interrupt aggregator
+         over TI System Control Interface available on some new TI's SoCs.
+         If you wish to use interrupt aggregator 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 0499fae148a9..caf6d084e0d4 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -95,3 +95,4 @@ 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_TI_SCI_INTR_IRQCHIP)      += irq-ti-sci-intr.o irq-ti-sci-common.o
+obj-$(CONFIG_TI_SCI_INTA_IRQCHIP)      += irq-ti-sci-inta.o irq-ti-sci-common.o
diff --git a/drivers/irqchip/irq-ti-sci-inta.c 
b/drivers/irqchip/irq-ti-sci-inta.c
new file mode 100644
index 000000000000..131944fec6fe
--- /dev/null
+++ b/drivers/irqchip/irq-ti-sci-inta.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Texas Instruments' K3 Interrupt Aggregator irqchip driver
+ *
+ * Copyright (C) 2018-2019 Texas Instruments Incorporated - http://www.ti.com/
+ *     Lokesh Vutla <lokeshvu...@ti.com>
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/msi.h>
+#include <linux/irqchip.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/irqdomain.h>
+#include <linux/interrupt.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+#include <linux/soc/ti/k3_inta_msi.h>
+#include <linux/irqchip/chained_irq.h>
+#include <asm-generic/msi.h>
+#include "irq-ti-sci-common.h"
+
+#define MAX_EVENTS_PER_VINT    64
+
+#define VINT_ENABLE_SET_OFFSET 0x0
+#define VINT_ENABLE_CLR_OFFSET 0x8
+#define VINT_STATUS_OFFSET     0x18
+
+/**
+ * struct ti_sci_inta_event_desc - Description of an event coming to
+ *                                Interrupt Aggregator.
+ * @global_event:      Global event number corresponding to this event
+ * @src_id:            TISCI device ID of the event source
+ * @src_index:         Event source index within the device.
+ */
+struct ti_sci_inta_event_desc {
+       u16 global_event;
+       u16 src_id;
+       u16 src_index;
+};
+
+/**
+ * struct ti_sci_inta_vint_desc - Description of a virtual interrupt coming out
+ *                               of Interrupt Aggregator.
+ * @domain:            Pointer to IRQ domain to which this vint belongs.
+ * @list:              List entry for the vint list
+ * @event_lock:                lock to guard the event map
+ * @event_map:         Bitmap to manage the allocation of events to vint.
+ * @events:            Array of event descriptors assigned to this vint.
+ * @parent_virq:       Linux IRQ number that gets attached to parent
+ * @vint_id:           TISCI vint ID
+ */
+struct ti_sci_inta_vint_desc {
+       struct irq_domain *domain;
+       struct list_head list;
+       struct mutex event_lock;
+       unsigned long *event_map;
+       struct ti_sci_inta_event_desc events[MAX_EVENTS_PER_VINT];
+       unsigned int parent_virq;
+       u16 vint_id;
+};
+
+/**
+ * struct ti_sci_inta_irq_domain - Structure representing a TISCI based
+ *                                Interrupt Aggregator IRQ domain.
+ * @sci:               Pointer to TISCI handle
+ * @vint:              TISCI resource pointer representing IA inerrupts.
+ * @global_event:      TISCI resource pointer representing global events.
+ * @vint_list:         List of the vints active in the system
+ * @base:              Base address of the memory mapped IO registers
+ * @ia_id:             TISCI device ID of this Interrupt Aggregator.
+ */
+struct ti_sci_inta_irq_domain {
+       const struct ti_sci_handle *sci;
+       struct ti_sci_resource *vint;
+       struct ti_sci_resource *global_event;
+       struct list_head vint_list;
+       void __iomem *base;
+       u16 ia_id;
+};
+
+static int __get_event_index(struct ti_sci_inta_vint_desc *vint_desc,
+                            int global_event)
+{
+       int event_index = -ENODEV, i;
+
+       for (i = 0; i < MAX_EVENTS_PER_VINT; i++) {
+               if (vint_desc->events[i].global_event == global_event) {
+                       event_index = i;
+                       break;
+               }
+       }
+
+       return event_index;
+}
+
+static void __ti_sci_inta_manage_event(struct irq_data *data, u32 offset)
+{
+       struct ti_sci_inta_vint_desc *vint_desc;
+       struct ti_sci_inta_irq_domain *inta;
+       int global_event, event_index;
+
+       vint_desc = irq_data_get_irq_chip_data(data);
+       global_event = data->hwirq;
+       event_index = __get_event_index(vint_desc, global_event);
+       inta = vint_desc->domain->host_data;
+
+       if (event_index < 0)
+               return;
+
+       writeq_relaxed(BIT(event_index), inta->base +
+                      vint_desc->vint_id * 0x1000 + offset);
+}
+
+static void ti_sci_inta_mask_irq(struct irq_data *data)
+{
+       __ti_sci_inta_manage_event(data, VINT_ENABLE_CLR_OFFSET);
+}
+
+static void ti_sci_inta_unmask_irq(struct irq_data *data)
+{
+       __ti_sci_inta_manage_event(data, VINT_ENABLE_SET_OFFSET);
+}
+
+static int ti_sci_inta_set_affinity(struct irq_data *d,
+                                   const struct cpumask *mask_val, bool force)
+{
+       struct ti_sci_inta_vint_desc *vint_desc = irq_data_get_irq_chip_data(d);
+       struct irq_chip *chip = irq_get_chip(vint_desc->parent_virq);
+       struct irq_data *data = irq_get_irq_data(vint_desc->parent_virq);
+
+       if (chip && chip->irq_set_affinity)
+               return chip->irq_set_affinity(data, mask_val, force);
+       else
+               return -EINVAL;
+}
+
+static struct irq_chip ti_sci_inta_irq_chip = {
+       .name                   = "INTA",
+       .irq_mask               = ti_sci_inta_mask_irq,
+       .irq_unmask             = ti_sci_inta_unmask_irq,
+       .irq_set_affinity       = ti_sci_inta_set_affinity,
+};
+
+/**
+ * ti_sci_free_event_irq() - Free an event from vint
+ * @domain:    Pointer to Interrupt Aggregator IRQ domain
+ * @vint_desc: Virtual interrupt descriptor containing the event.
+ * @global_event: Global event id to be freed.
+ */
+static void ti_sci_free_event_irq(struct irq_domain *domain,
+                                 struct ti_sci_inta_vint_desc *vint_desc,
+                                 u16 global_event)
+{
+       struct ti_sci_inta_irq_domain *inta = domain->host_data;
+       struct ti_sci_inta_event_desc *event_desc;
+       int event_index = 0;
+
+       event_index = __get_event_index(vint_desc, global_event);
+       event_desc = &vint_desc->events[event_index];
+       inta->sci->ops.rm_irq_ops.free_event_map(inta->sci,
+                                                event_desc->src_id,
+                                                event_desc->src_index,
+                                                inta->ia_id,
+                                                vint_desc->vint_id,
+                                                event_desc->global_event,
+                                                event_index);
+
+       clear_bit(event_index, vint_desc->event_map);
+
+       ti_sci_release_resource(inta->global_event, event_desc->global_event);
+}
+
+static void ti_sci_inta_free_vint(struct ti_sci_inta_irq_domain *inta,
+                                 struct ti_sci_inta_vint_desc *vint_desc)
+{
+       /* If all events are cleared, release vint */
+       if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) ==
+           MAX_EVENTS_PER_VINT)
+               ti_sci_release_resource(inta->vint, vint_desc->vint_id);
+}
+
+/**
+ * ti_sci_inta_irq_domain_free() - Free an IRQ from the IRQ domain
+ * @domain:    Domain to which the irqs belong
+ * @virq:      base linux virtual IRQ to be freed.
+ * @nr_irqs:   Number of continuous irqs to be freed
+ */
+static void ti_sci_inta_irq_domain_free(struct irq_domain *domain,
+                                       unsigned int virq, unsigned int nr_irqs)
+{
+       struct ti_sci_inta_vint_desc *vint_desc;
+       struct irq_data *data;
+
+       data = irq_domain_get_irq_data(domain, virq);
+       vint_desc = irq_data_get_irq_chip_data(data);
+
+       ti_sci_free_event_irq(domain, vint_desc, data->hwirq);
+       ti_sci_inta_free_vint(domain->host_data, vint_desc);
+       irq_domain_reset_irq_data(data);
+}
+
+/**
+ * ti_sci_allocate_event_irq() - Allocate an event to a IA vint.
+ *
+ * Return global_event if all went ok else appropriate error value.
+ */
+static
+int ti_sci_allocate_event_irq(struct irq_domain *domain, msi_alloc_info_t *arg)
+{
+       struct ti_sci_inta_irq_domain *inta = domain->host_data;
+       struct ti_sci_inta_event_desc *event_desc;
+       struct ti_sci_inta_vint_desc *vint_desc;
+       u16 free_bit, src_id, src_index;
+       int err;
+
+       src_id = HWIRQ_TO_DEVID(arg->hwirq);
+       src_index = HWIRQ_TO_IRQID(arg->hwirq);
+       vint_desc = arg->scratchpad[0].ptr;
+
+       mutex_lock(&vint_desc->event_lock);
+       free_bit = find_first_zero_bit(vint_desc->event_map,
+                                      MAX_EVENTS_PER_VINT);
+       if (free_bit != MAX_EVENTS_PER_VINT)
+               set_bit(free_bit, vint_desc->event_map);
+       mutex_unlock(&vint_desc->event_lock);
+
+       event_desc = &vint_desc->events[free_bit];
+
+       event_desc->src_id = src_id;
+       event_desc->src_index = src_index;
+       event_desc->global_event = ti_sci_get_free_resource(inta->global_event);
+       if (event_desc->global_event == TI_SCI_RESOURCE_NULL) {
+               err = -EINVAL;
+               goto free_event;
+       }
+
+       err = inta->sci->ops.rm_irq_ops.set_event_map(inta->sci,
+                                                     src_id, src_index,
+                                                     inta->ia_id,
+                                                     vint_desc->vint_id,
+                                                     event_desc->global_event,
+                                                     free_bit);
+       if (err)
+               goto free_global_event;
+
+       return event_desc->global_event;
+free_global_event:
+       ti_sci_release_resource(inta->global_event, event_desc->global_event);
+free_event:
+       clear_bit(free_bit, vint_desc->event_map);
+       return err;
+}
+
+struct ti_sci_inta_vint_desc *
+ti_sci_inta_get_vint(struct ti_sci_inta_irq_domain *inta, u16 vint)
+{
+       struct ti_sci_inta_vint_desc *vint_desc;
+
+       list_for_each_entry(vint_desc, &inta->vint_list, list)
+               if (vint_desc->vint_id == vint)
+                       return vint_desc;
+       return NULL;
+}
+
+/**
+ * ti_sci_inta_irq_domain_alloc() - Allocate Interrupt aggregator IRQs
+ * @domain:    Point to the interrupt aggregator 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_inta_irq_domain_alloc(struct irq_domain *domain,
+                                       unsigned int virq, unsigned int nr_irqs,
+                                       void *data)
+{
+       struct ti_sci_inta_irq_domain *inta = domain->host_data;
+       msi_alloc_info_t *arg = data;
+       int hwirq;
+       u16 vint;
+
+       if (arg->desc->inta.share) {
+               if (!arg->scratchpad[0].ptr) {
+                       vint = ti_sci_get_free_resource(inta->vint);
+                       arg->scratchpad[0].ptr = ti_sci_inta_get_vint(inta,
+                                                                     vint);
+               }
+       } else {
+               vint = ti_sci_get_free_resource(inta->vint);
+               arg->scratchpad[0].ptr = ti_sci_inta_get_vint(inta, vint);
+       }
+
+       hwirq = ti_sci_allocate_event_irq(domain, arg);
+       if (hwirq < 0)
+               return hwirq;
+
+       irq_domain_set_info(domain, virq, hwirq, &ti_sci_inta_irq_chip,
+                           arg->scratchpad[0].ptr, handle_simple_irq,
+                           NULL, NULL);
+
+       return 0;
+}
+
+static const struct irq_domain_ops ti_sci_inta_irq_domain_ops = {
+       .alloc          = ti_sci_inta_irq_domain_alloc,
+       .free           = ti_sci_inta_irq_domain_free,
+};
+
+static struct irq_chip inta_msi_irq_chip = {
+       .name           = "MSI-INTA",
+};
+
+static void inta_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+       arg->desc = desc;
+       arg->hwirq = TO_HWIRQ(desc->inta.dev_id, desc->inta.index);
+}
+
+static struct msi_domain_ops inta_msi_ops = {
+       .set_desc       = inta_msi_set_desc,
+};
+
+static struct msi_domain_info inta_msi_domain_info = {
+       .flags  = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
+       .ops    = &inta_msi_ops,
+       .chip   = &inta_msi_irq_chip,
+};
+
+static void inta_msi_irq_handler(struct irq_desc *desc)
+{
+       struct ti_sci_inta_vint_desc *vint_desc;
+       struct ti_sci_inta_irq_domain *inta;
+       struct irq_domain *domain;
+       struct irq_data *irq_data;
+       u32 hwirq, bit, virq;
+       u64 val;
+
+       vint_desc = irq_desc_get_handler_data(desc);
+       domain = vint_desc->domain;
+       inta = domain->host_data;
+
+       chained_irq_enter(irq_desc_get_chip(desc), desc);
+
+       val = readq_relaxed(inta->base + vint_desc->vint_id * 0x1000 +
+                           VINT_STATUS_OFFSET);
+
+       for (bit = 0; bit < MAX_EVENTS_PER_VINT; bit++) {
+               if (BIT(bit) & val) {
+                       hwirq = vint_desc->events[bit].global_event;
+                       virq = irq_find_mapping(domain, hwirq);
+                       irq_data = irq_get_irq_data(virq);
+                       if (irqd_get_trigger_type(irq_data) ==
+                           IRQF_TRIGGER_HIGH)
+                               writeq_relaxed(BIT(bit),
+                                              inta->base + vint_desc->vint_id *
+                                              0x1000 + VINT_STATUS_OFFSET);
+
+                       if (virq)
+                               generic_handle_irq(virq);
+               }
+       }
+
+       chained_irq_exit(irq_desc_get_chip(desc), desc);
+}
+
+/**
+ * ti_sci_inta_alloc_parent_irq() - Allocate parent irq to Interrupt aggregator
+ * @domain:    IRQ domain corresponding to Interrupt Aggregator
+ * @virq:      Linux virtual IRQ number
+ *
+ * Return 0 if all went well else corresponding error value.
+ */
+static int ti_sci_inta_alloc_parent_irq(struct irq_domain *domain, u16 vint_id)
+{
+       struct ti_sci_inta_irq_domain *inta = domain->host_data;
+       struct ti_sci_inta_vint_desc *vint_desc;
+       struct irq_fwspec parent_fwspec;
+       unsigned int virq;
+
+       vint_desc = kzalloc(sizeof(*vint_desc), GFP_KERNEL);
+       if (!vint_desc)
+               return -ENOMEM;
+
+       vint_desc->event_map = kcalloc(BITS_TO_LONGS(MAX_EVENTS_PER_VINT),
+                                      sizeof(*vint_desc->event_map),
+                                      GFP_KERNEL);
+       if (!vint_desc->event_map) {
+               kfree(vint_desc);
+               return -ENOMEM;
+       }
+
+       vint_desc->domain = domain;
+       vint_desc->vint_id = vint_id;
+       INIT_LIST_HEAD(&vint_desc->list);
+       list_add_tail(&vint_desc->list, &inta->vint_list);
+
+       parent_fwspec.fwnode = domain->parent->fwnode;
+       parent_fwspec.param_count = 4;
+       /* Interrupt parent is Interrupt Router */
+       parent_fwspec.param[0] = inta->ia_id;
+       parent_fwspec.param[1] = vint_desc->vint_id;
+       parent_fwspec.param[2] = IRQF_TRIGGER_HIGH;
+       parent_fwspec.param[3] = 1;
+
+       virq = irq_create_fwspec_mapping(&parent_fwspec);
+       if (virq <= 0) {
+               kfree(vint_desc->event_map);
+               kfree(vint_desc);
+               return -ERANGE;
+       }
+
+       irq_set_chained_handler_and_data(virq, inta_msi_irq_handler, vint_desc);
+
+       mutex_init(&vint_desc->event_lock);
+
+       return 0;
+}
+
+static int ti_sci_inta_irq_domain_probe(struct platform_device *pdev)
+{
+       struct irq_domain *parent_domain, *domain, *msi_domain;
+       struct device_node *parent_node, *node;
+       struct ti_sci_inta_irq_domain *inta;
+       struct device *dev = &pdev->dev;
+       struct resource *res;
+       int ret, set, i;
+
+       node = dev_of_node(dev);
+       parent_node = of_irq_find_parent(node);
+       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)
+               return -EPROBE_DEFER;
+
+       inta = devm_kzalloc(dev, sizeof(*inta), GFP_KERNEL);
+       if (!inta)
+               return -ENOMEM;
+
+       inta->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
+       if (IS_ERR(inta->sci)) {
+               ret = PTR_ERR(inta->sci);
+               if (ret != -EPROBE_DEFER)
+                       dev_err(dev, "ti,sci read fail %d\n", ret);
+               inta->sci = NULL;
+               return ret;
+       }
+
+       ret = of_property_read_u32(dev->of_node, "ti,sci-dev-id",
+                                  (u32 *)&inta->ia_id);
+       if (ret) {
+               dev_err(dev, "missing 'ti,sci-dev-id' property\n");
+               return -EINVAL;
+       }
+
+       inta->vint = devm_ti_sci_get_of_resource(inta->sci, dev,
+                                                inta->ia_id,
+                                                "ti,sci-rm-range-vint");
+       if (IS_ERR(inta->vint)) {
+               dev_err(dev, "VINT resource allocation failed\n");
+               return PTR_ERR(inta->vint);
+       }
+
+       inta->global_event =
+               devm_ti_sci_get_of_resource(inta->sci, dev,
+                                           inta->ia_id,
+                                           "ti,sci-rm-range-global-event");
+       if (IS_ERR(inta->global_event)) {
+               dev_err(dev, "Global event resource allocation failed\n");
+               return PTR_ERR(inta->global_event);
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       inta->base = devm_ioremap_resource(dev, res);
+       if (IS_ERR(inta->base))
+               return -ENODEV;
+
+       domain = irq_domain_add_hierarchy(parent_domain, 0, 0, dev_of_node(dev),
+                                         &ti_sci_inta_irq_domain_ops, inta);
+       if (!domain) {
+               dev_err(dev, "Failed to allocate IRQ domain\n");
+               return -ENOMEM;
+       }
+
+       msi_domain = inta_msi_create_irq_domain(of_node_to_fwnode(node),
+                                               &inta_msi_domain_info,
+                                               domain);
+       if (!msi_domain) {
+               irq_domain_remove(domain);
+               dev_err(dev, "Failed to allocate msi domain\n");
+               return -ENOMEM;
+       }
+
+       INIT_LIST_HEAD(&inta->vint_list);
+       for (set = 0; set < inta->vint->sets; set++) {
+               for (i = 0; i < inta->vint->desc[set].num; i++) {
+                       if (ti_sci_inta_alloc_parent_irq(domain,
+                                       inta->vint->desc[set].start + i))
+                               break;
+               }
+       }
+
+       return 0;
+}
+
+static const struct of_device_id ti_sci_inta_irq_domain_of_match[] = {
+       { .compatible = "ti,sci-inta", },
+       { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_sci_inta_irq_domain_of_match);
+
+static struct platform_driver ti_sci_inta_irq_domain_driver = {
+       .probe = ti_sci_inta_irq_domain_probe,
+       .driver = {
+               .name = "ti-sci-inta",
+               .of_match_table = ti_sci_inta_irq_domain_of_match,
+       },
+};
+module_platform_driver(ti_sci_inta_irq_domain_driver);
+
+MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ticom>");
+MODULE_DESCRIPTION("K3 Interrupt Aggregator driver over TI SCI protocol");
+MODULE_LICENSE("GPL v2");
-- 
2.19.2

Reply via email to