diff options
author | Lokesh Vutla <lokeshvutla@ti.com> | 2019-04-30 13:12:27 +0300 |
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committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-05-01 12:49:13 +0300 |
commit | 9f1463b86c13277d0bd88d5ee359577ef40f4da7 (patch) | |
tree | 6a9d4da6e6fa9c3f1a03f5b4ad22800569069e51 /drivers/irqchip/irq-ti-sci-inta.c | |
parent | accaf1fbfb5daebc9e5ea55644ff8fff3679b838 (diff) | |
download | linux-9f1463b86c13277d0bd88d5ee359577ef40f4da7.tar.xz |
irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver
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 the required infrastructure to
allow the allocation and routing of these events.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'drivers/irqchip/irq-ti-sci-inta.c')
-rw-r--r-- | drivers/irqchip/irq-ti-sci-inta.c | 577 |
1 files changed, 577 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-ti-sci-inta.c b/drivers/irqchip/irq-ti-sci-inta.c new file mode 100644 index 000000000000..87e0abe0041f --- /dev/null +++ b/drivers/irqchip/irq-ti-sci-inta.c @@ -0,0 +1,577 @@ +// 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 <lokeshvutla@ti.com> + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/interrupt.h> +#include <linux/msi.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/soc/ti/ti_sci_protocol.h> +#include <asm-generic/msi.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 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. This serves + * as a mapping table for global event, + * hwirq and vint bit. + * @global_event: Global event number corresponding to this event + * @hwirq: Hwirq of the incoming interrupt + * @vint_bit: Corresponding vint bit to which this event is attached. + */ +struct ti_sci_inta_event_desc { + u16 global_event; + u32 hwirq; + u8 vint_bit; +}; + +/** + * 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_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; + DECLARE_BITMAP(event_map, MAX_EVENTS_PER_VINT); + 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 + * @vint_mutex: Mutex to protect vint_list + * @base: Base address of the memory mapped IO registers + * @pdev: Pointer to platform device. + */ +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; + /* Mutex to protect vint list */ + struct mutex vint_mutex; + void __iomem *base; + struct platform_device *pdev; +}; + +#define to_vint_desc(e, i) container_of(e, struct ti_sci_inta_vint_desc, \ + events[i]) + +/** + * ti_sci_inta_irq_handler() - Chained IRQ handler for the vint irqs + * @desc: Pointer to irq_desc corresponding to the irq + */ +static void ti_sci_inta_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; + unsigned int virq, bit; + unsigned long 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_each_set_bit(bit, &val, MAX_EVENTS_PER_VINT) { + virq = irq_find_mapping(domain, vint_desc->events[bit].hwirq); + 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 + * + * Return 0 if all went well else corresponding error value. + */ +static struct ti_sci_inta_vint_desc *ti_sci_inta_alloc_parent_irq(struct irq_domain *domain) +{ + 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 parent_virq; + u16 vint_id; + + vint_id = ti_sci_get_free_resource(inta->vint); + if (vint_id == TI_SCI_RESOURCE_NULL) + return ERR_PTR(-EINVAL); + + vint_desc = kzalloc(sizeof(*vint_desc), GFP_KERNEL); + if (!vint_desc) + return ERR_PTR(-ENOMEM); + + vint_desc->domain = domain; + vint_desc->vint_id = vint_id; + INIT_LIST_HEAD(&vint_desc->list); + + parent_fwspec.fwnode = of_node_to_fwnode(of_irq_find_parent(dev_of_node(&inta->pdev->dev))); + parent_fwspec.param_count = 2; + parent_fwspec.param[0] = inta->pdev->id; + parent_fwspec.param[1] = vint_desc->vint_id; + + parent_virq = irq_create_fwspec_mapping(&parent_fwspec); + if (parent_virq <= 0) { + kfree(vint_desc); + return ERR_PTR(parent_virq); + } + vint_desc->parent_virq = parent_virq; + + list_add_tail(&vint_desc->list, &inta->vint_list); + irq_set_chained_handler_and_data(vint_desc->parent_virq, + ti_sci_inta_irq_handler, vint_desc); + + return vint_desc; +} + +/** + * ti_sci_inta_alloc_event() - Attach an event to a IA vint. + * @vint_desc: Pointer to vint_desc to which the event gets attached + * @free_bit: Bit inside vint to which event gets attached + * @hwirq: hwirq of the input event + * + * Return event_desc pointer if all went ok else appropriate error value. + */ +static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_event(struct ti_sci_inta_vint_desc *vint_desc, + u16 free_bit, + u32 hwirq) +{ + struct ti_sci_inta_irq_domain *inta = vint_desc->domain->host_data; + struct ti_sci_inta_event_desc *event_desc; + u16 dev_id, dev_index; + int err; + + dev_id = HWIRQ_TO_DEVID(hwirq); + dev_index = HWIRQ_TO_IRQID(hwirq); + + event_desc = &vint_desc->events[free_bit]; + event_desc->hwirq = hwirq; + event_desc->vint_bit = free_bit; + event_desc->global_event = ti_sci_get_free_resource(inta->global_event); + if (event_desc->global_event == TI_SCI_RESOURCE_NULL) + return ERR_PTR(-EINVAL); + + err = inta->sci->ops.rm_irq_ops.set_event_map(inta->sci, + dev_id, dev_index, + inta->pdev->id, + vint_desc->vint_id, + event_desc->global_event, + free_bit); + if (err) + goto free_global_event; + + return event_desc; +free_global_event: + ti_sci_release_resource(inta->global_event, event_desc->global_event); + return ERR_PTR(err); +} + +/** + * ti_sci_inta_alloc_irq() - Allocate an irq within INTA domain + * @domain: irq_domain pointer corresponding to INTA + * @hwirq: hwirq of the input event + * + * Note: Allocation happens in the following manner: + * - Find a free bit available in any of the vints available in the list. + * - If not found, allocate a vint from the vint pool + * - Attach the free bit to input hwirq. + * Return event_desc if all went ok else appropriate error value. + */ +static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_irq(struct irq_domain *domain, + u32 hwirq) +{ + struct ti_sci_inta_irq_domain *inta = domain->host_data; + struct ti_sci_inta_vint_desc *vint_desc = NULL; + struct ti_sci_inta_event_desc *event_desc; + u16 free_bit; + + mutex_lock(&inta->vint_mutex); + list_for_each_entry(vint_desc, &inta->vint_list, list) { + 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); + goto alloc_event; + } + } + + /* No free bits available. Allocate a new vint */ + vint_desc = ti_sci_inta_alloc_parent_irq(domain); + if (IS_ERR(vint_desc)) { + mutex_unlock(&inta->vint_mutex); + return ERR_PTR(PTR_ERR(vint_desc)); + } + + free_bit = find_first_zero_bit(vint_desc->event_map, + MAX_EVENTS_PER_VINT); + set_bit(free_bit, vint_desc->event_map); + +alloc_event: + event_desc = ti_sci_inta_alloc_event(vint_desc, free_bit, hwirq); + if (IS_ERR(event_desc)) + clear_bit(free_bit, vint_desc->event_map); + + mutex_unlock(&inta->vint_mutex); + return event_desc; +} + +/** + * ti_sci_inta_free_parent_irq() - Free a parent irq to INTA + * @inta: Pointer to inta domain. + * @vint_desc: Pointer to vint_desc that needs to be freed. + */ +static void ti_sci_inta_free_parent_irq(struct ti_sci_inta_irq_domain *inta, + struct ti_sci_inta_vint_desc *vint_desc) +{ + if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) == MAX_EVENTS_PER_VINT) { + list_del(&vint_desc->list); + ti_sci_release_resource(inta->vint, vint_desc->vint_id); + irq_dispose_mapping(vint_desc->parent_virq); + kfree(vint_desc); + } +} + +/** + * ti_sci_inta_free_irq() - Free an IRQ within INTA domain + * @event_desc: Pointer to event_desc that needs to be freed. + * @hwirq: Hwirq number within INTA domain that needs to be freed + */ +static void ti_sci_inta_free_irq(struct ti_sci_inta_event_desc *event_desc, + u32 hwirq) +{ + struct ti_sci_inta_vint_desc *vint_desc; + struct ti_sci_inta_irq_domain *inta; + + vint_desc = to_vint_desc(event_desc, event_desc->vint_bit); + inta = vint_desc->domain->host_data; + /* free event irq */ + mutex_lock(&inta->vint_mutex); + inta->sci->ops.rm_irq_ops.free_event_map(inta->sci, + HWIRQ_TO_DEVID(hwirq), + HWIRQ_TO_IRQID(hwirq), + inta->pdev->id, + vint_desc->vint_id, + event_desc->global_event, + event_desc->vint_bit); + + clear_bit(event_desc->vint_bit, vint_desc->event_map); + ti_sci_release_resource(inta->global_event, event_desc->global_event); + event_desc->global_event = TI_SCI_RESOURCE_NULL; + event_desc->hwirq = 0; + + ti_sci_inta_free_parent_irq(inta, vint_desc); + mutex_unlock(&inta->vint_mutex); +} + +/** + * ti_sci_inta_request_resources() - Allocate resources for input irq + * @data: Pointer to corresponding irq_data + * + * Note: This is the core api where the actual allocation happens for input + * hwirq. This allocation involves creating a parent irq for vint. + * If this is done in irq_domain_ops.alloc() then a deadlock is reached + * for allocation. So this allocation is being done in request_resources() + * + * Return: 0 if all went well else corresponding error. + */ +static int ti_sci_inta_request_resources(struct irq_data *data) +{ + struct ti_sci_inta_event_desc *event_desc; + + event_desc = ti_sci_inta_alloc_irq(data->domain, data->hwirq); + if (IS_ERR(event_desc)) + return PTR_ERR(event_desc); + + data->chip_data = event_desc; + + return 0; +} + +/** + * ti_sci_inta_release_resources - Release resources for input irq + * @data: Pointer to corresponding irq_data + * + * Note: Corresponding to request_resources(), all the unmapping and deletion + * of parent vint irqs happens in this api. + */ +static void ti_sci_inta_release_resources(struct irq_data *data) +{ + struct ti_sci_inta_event_desc *event_desc; + + event_desc = irq_data_get_irq_chip_data(data); + ti_sci_inta_free_irq(event_desc, data->hwirq); +} + +/** + * ti_sci_inta_manage_event() - Control the event based on the offset + * @data: Pointer to corresponding irq_data + * @offset: register offset using which event is controlled. + */ +static void ti_sci_inta_manage_event(struct irq_data *data, u32 offset) +{ + struct ti_sci_inta_event_desc *event_desc; + struct ti_sci_inta_vint_desc *vint_desc; + struct ti_sci_inta_irq_domain *inta; + + event_desc = irq_data_get_irq_chip_data(data); + vint_desc = to_vint_desc(event_desc, event_desc->vint_bit); + inta = data->domain->host_data; + + writeq_relaxed(BIT(event_desc->vint_bit), + inta->base + vint_desc->vint_id * 0x1000 + offset); +} + +/** + * ti_sci_inta_mask_irq() - Mask an event + * @data: Pointer to corresponding irq_data + */ +static void ti_sci_inta_mask_irq(struct irq_data *data) +{ + ti_sci_inta_manage_event(data, VINT_ENABLE_CLR_OFFSET); +} + +/** + * ti_sci_inta_unmask_irq() - Unmask an event + * @data: Pointer to corresponding irq_data + */ +static void ti_sci_inta_unmask_irq(struct irq_data *data) +{ + ti_sci_inta_manage_event(data, VINT_ENABLE_SET_OFFSET); +} + +/** + * ti_sci_inta_ack_irq() - Ack an event + * @data: Pointer to corresponding irq_data + */ +static void ti_sci_inta_ack_irq(struct irq_data *data) +{ + /* + * Do not clear the event if hardware is capable of sending + * a down event. + */ + if (irqd_get_trigger_type(data) != IRQF_TRIGGER_HIGH) + ti_sci_inta_manage_event(data, VINT_STATUS_OFFSET); +} + +static int ti_sci_inta_set_affinity(struct irq_data *d, + const struct cpumask *mask_val, bool force) +{ + return -EINVAL; +} + +/** + * ti_sci_inta_set_type() - Update the trigger type of the irq. + * @data: Pointer to corresponding irq_data + * @type: Trigger type as specified by user + * + * Note: This updates the handle_irq callback for level msi. + * + * Return 0 if all went well else appropriate error. + */ +static int ti_sci_inta_set_type(struct irq_data *data, unsigned int type) +{ + /* + * .alloc default sets handle_edge_irq. But if the user specifies + * that IRQ is level MSI, then update the handle to handle_level_irq + */ + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQF_TRIGGER_HIGH: + irq_set_handler_locked(data, handle_level_irq); + return 0; + case IRQF_TRIGGER_RISING: + return 0; + default: + return -EINVAL; + } + + return -EINVAL; +} + +static struct irq_chip ti_sci_inta_irq_chip = { + .name = "INTA", + .irq_ack = ti_sci_inta_ack_irq, + .irq_mask = ti_sci_inta_mask_irq, + .irq_set_type = ti_sci_inta_set_type, + .irq_unmask = ti_sci_inta_unmask_irq, + .irq_set_affinity = ti_sci_inta_set_affinity, + .irq_request_resources = ti_sci_inta_request_resources, + .irq_release_resources = ti_sci_inta_release_resources, +}; + +/** + * 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 irq_data *data = irq_domain_get_irq_data(domain, virq); + + irq_domain_reset_irq_data(data); +} + +/** + * 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 + * + * No actual allocation happens here. + * + * 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) +{ + msi_alloc_info_t *arg = data; + + irq_domain_set_info(domain, virq, arg->hwirq, &ti_sci_inta_irq_chip, + NULL, handle_edge_irq, NULL, NULL); + + return 0; +} + +static const struct irq_domain_ops ti_sci_inta_irq_domain_ops = { + .free = ti_sci_inta_irq_domain_free, + .alloc = ti_sci_inta_irq_domain_alloc, +}; + +static int ti_sci_inta_irq_domain_probe(struct platform_device *pdev) +{ + struct irq_domain *parent_domain, *domain; + struct device_node *parent_node, *node; + struct ti_sci_inta_irq_domain *inta; + struct device *dev = &pdev->dev; + struct resource *res; + int ret; + + 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->pdev = pdev; + 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", &pdev->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, pdev->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, pdev->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_linear(dev_of_node(dev), + ti_sci_get_num_resources(inta->vint), + &ti_sci_inta_irq_domain_ops, inta); + if (!domain) { + dev_err(dev, "Failed to allocate IRQ domain\n"); + return -ENOMEM; + } + + INIT_LIST_HEAD(&inta->vint_list); + mutex_init(&inta->vint_mutex); + + 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"); |