Re: [PATCH v6 09/12] irqchip: ti-sci-inta: Add support for Interrupt Aggregator driver

From: Marc Zyngier
Date: Wed Apr 17 2019 - 10:15:06 EST


Hi Lokesh,

On 10/04/2019 05:13, Lokesh Vutla wrote:
> 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 <lokeshvutla@xxxxxx>
> ---
> Changes since v5:
> - Moved all the allocation of events and parent irqs to .irq_request_resources
> callback of irqchip. This is based on the offline discussion with Marc.
>
> Marc,
> This version has a deviation from our discussion:
> - Could not create separate irq_domains for each output(vint) of INTA, instead
> stick to a single irq_domain for the entire INTA. Because when creating
> msi_domain there is no parent available to attach. Even then I create
> irq_domains for all the available vints during probe, how do we decide
> which is the parent of msi_domain?

Yeah, you're right. The top-down allocation assumes that we already have
setup the domain hierarchy, and this delayed allocation scheme breaks
it. Oh well, never mind.

>
>
> MAINTAINERS | 1 +
> drivers/irqchip/Kconfig | 11 +
> drivers/irqchip/Makefile | 1 +
> drivers/irqchip/irq-ti-sci-inta.c | 622 ++++++++++++++++++++++++++++++
> 4 files changed, 635 insertions(+)
> create mode 100644 drivers/irqchip/irq-ti-sci-inta.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 90173038f674..ba88b3033fe4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -15352,6 +15352,7 @@ F: drivers/reset/reset-ti-sci.c
> F: Documentation/devicetree/bindings/interrupt-controller/ti,sci-intr.txt
> F: Documentation/devicetree/bindings/interrupt-controller/ti,sci-inta.txt
> F: drivers/irqchip/irq-ti-sci-intr.c
> +F: drivers/irqchip/irq-ti-sci-inta.c
>
> Texas Instruments ASoC drivers
> M: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index a1ff64c1d40d..946c062fcec0 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -436,6 +436,17 @@ 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
> + 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 fa5c865788b5..8a33013da953 100644
> --- a/drivers/irqchip/Makefile
> +++ b/drivers/irqchip/Makefile
> @@ -98,3 +98,4 @@ 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
> +obj-$(CONFIG_TI_SCI_INTA_IRQCHIP) += irq-ti-sci-inta.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..3eb935ebe10f
> --- /dev/null
> +++ b/drivers/irqchip/irq-ti-sci-inta.c
> @@ -0,0 +1,622 @@
> +// 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@xxxxxx>
> + */
> +
> +#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/irqchip/chained_irq.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 between global
> + * event and hwirq.
> + * @global_event: Global event number corresponding to this event
> + * @hwirq: Hwirq of the incoming interrupt
> + */
> +struct ti_sci_inta_event_desc {
> + u16 global_event;
> + u32 hwirq;
> +};
> +
> +/**
> + * 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.
> + * @event_mutex: Mutex to protect allocation of events.
> + * @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;
> + unsigned long *event_map;
> + /* Mutex to protect allocation of events */
> + struct mutex event_mutex;

As mentioned in another email, this needs to be a spinlock, as the lock
may be taken in atomic context.

> + 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;
> +};
> +
> +/**
> + * 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;
> + 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) {
> + 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)

nit: do not split lines like this, specially not with the * on a
different line than the type it applies to.

> +{
> + struct ti_sci_inta_irq_domain *inta = domain->host_data;
> + struct ti_sci_inta_vint_desc *vint_desc;
> + struct irq_fwspec parent_fwspec;
> + 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->event_map = kcalloc(BITS_TO_LONGS(MAX_EVENTS_PER_VINT),
> + sizeof(*vint_desc->event_map),
> + GFP_KERNEL);

You already have an array of MAX_EVENTS_PER_VINT (events) in this
structure. Why don't you simply declare it as a
MAX_EVENTS_PER_VINT-sized bitmap and save yourself the allocation?

> + if (!vint_desc->event_map) {
> + kfree(vint_desc);
> + return ERR_PTR(-ENOMEM);
> + }
> + mutex_init(&vint_desc->event_mutex);
> +
> + vint_desc->domain = domain;
> + vint_desc->vint_id = vint_id;
> + INIT_LIST_HEAD(&vint_desc->list);
> +
> + mutex_lock(&inta->vint_mutex);
> + list_add_tail(&vint_desc->list, &inta->vint_list);
> + mutex_unlock(&inta->vint_mutex);
> +
> + parent_fwspec.fwnode =
> + of_node_to_fwnode(of_irq_find_parent(dev_of_node(&inta->pdev->dev)));

single line.

> + parent_fwspec.param_count = 3;
> + parent_fwspec.param[0] = inta->pdev->id;
> + parent_fwspec.param[1] = vint_desc->vint_id;
> + parent_fwspec.param[2] = 1;
> +
> + vint_desc->parent_virq = irq_create_fwspec_mapping(&parent_fwspec);
> + if (vint_desc->parent_virq <= 0)
> + return ERR_PTR(vint_desc->parent_virq);

Don't you need to free vint_desc (and its event_map) here?

> +
> + 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.
> + * @inta: Pointer to INTA domain descriptor
> + * @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 global_event if all went ok else appropriate error value.
> + */
> +static
> +int ti_sci_inta_alloc_event(struct ti_sci_inta_irq_domain *inta,
> + struct ti_sci_inta_vint_desc *vint_desc,
> + u16 free_bit, u32 hwirq)
> +{
> + 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];
> + mutex_lock(&vint_desc->event_mutex);
> + event_desc->hwirq = hwirq;
> + 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_vint_bit;
> + }
> +
> + 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;
> +
> + mutex_unlock(&vint_desc->event_mutex);
> + return 0;
> +free_global_event:
> + ti_sci_release_resource(inta->global_event, event_desc->global_event);
> +free_vint_bit:
> + clear_bit(free_bit, vint_desc->event_map);
> + mutex_unlock(&vint_desc->event_mutex);
> + return 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 vint_desc if all went ok else appropriate error value.
> + */
> +static struct ti_sci_inta_vint_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;
> + u16 free_bit;
> + int ret;
> +
> + mutex_lock(&inta->vint_mutex);
> + list_for_each_entry(vint_desc, &inta->vint_list, list) {
> + mutex_lock(&vint_desc->event_mutex);
> + 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_mutex);
> + mutex_unlock(&inta->vint_mutex);
> + goto alloc_event;
> + }
> + mutex_unlock(&vint_desc->event_mutex);
> + }
> + mutex_unlock(&inta->vint_mutex);
> +
> + /* No free bits available. Allocate a new vint */
> + vint_desc = ti_sci_inta_alloc_parent_irq(domain);
> + if (IS_ERR(vint_desc))
> + return vint_desc;
> +
> + mutex_lock(&vint_desc->event_mutex);
> + free_bit = find_first_zero_bit(vint_desc->event_map,
> + MAX_EVENTS_PER_VINT);
> + set_bit(free_bit, vint_desc->event_map);
> + mutex_unlock(&vint_desc->event_mutex);
> +
> +alloc_event:
> + ret = ti_sci_inta_alloc_event(inta, vint_desc, free_bit, hwirq);
> + if (ret)
> + return ERR_PTR(ret);

Without freeing the allocated bit?

> +
> + return vint_desc;
> +}
> +
> +/**
> + * __get_event_index() - Convert the hwirq to corresponding bit inside vint.
> + * @vint_desc: Pointer to vint_desc to which the hwirq is attached
> + * @hwirq: hwirq number within the domain
> + *
> + * Return the vint bit to which the hwirq is attached.
> + */
> +static int __get_event_index(struct ti_sci_inta_vint_desc *vint_desc, u32 hwirq)
> +{
> + int i;
> +
> + mutex_lock(&vint_desc->event_mutex);
> + for (i = 0; i < MAX_EVENTS_PER_VINT; i++)
> + if (vint_desc->events[i].hwirq == hwirq) {
> + mutex_unlock(&vint_desc->event_mutex);
> + return i;
> + }
> +
> + mutex_unlock(&vint_desc->event_mutex);
> + return -ENODEV;

OK, this is terrible. Having this loop on every mask/unmask/ack, plus
the contention on the lock (64:1, great) is just going to ruin latency.

Can't you spare 5 bits in hwirq to encode the index? Somehow, I don't
really believe that you do have 16bits of DEVID *and* 16bits of IRQID
(whatever the later is). Or allocate some per interrupt data that allows
the retrieval of the index in O(1)?

It would also solve your locking issue...

> +}
> +
> +/**
> + * ti_sci_inta_free_parent_irq() - Free a parent irq to INTA
> + * domain: domain corresponding to INTA
> + */
> +static void ti_sci_inta_free_parent_irq(struct irq_domain *domain,
> + struct ti_sci_inta_vint_desc *vint_desc)
> +{
> + struct ti_sci_inta_irq_domain *inta = domain->host_data;
> +
> + mutex_lock(&inta->vint_mutex);
> + list_del(&vint_desc->list);
> + mutex_unlock(&inta->vint_mutex);
> + irq_dispose_mapping(vint_desc->parent_virq);
> + ti_sci_release_resource(inta->vint, vint_desc->vint_id);
> + kfree(vint_desc->event_map);
> + kfree(vint_desc);
> +}
> +
> +/**
> + * ti_sci_inta_free_irq() - Free an IRQ within INTA domain
> + * domain: Domain corresponding to INTA
> + * vint_desc: Pointer to vint_desc from which irq needs to be freed
> + * hwirq: Hwirq number within INTA domain that needs to be freed
> + */
> +static void ti_sci_inta_free_irq(struct irq_domain *domain,
> + struct ti_sci_inta_vint_desc *vint_desc,
> + u32 hwirq)
> +{
> + struct ti_sci_inta_irq_domain *inta = domain->host_data;
> + struct ti_sci_inta_event_desc *event_desc;
> + int event_index = 0;
> +
> + /* free event irq */
> + event_index = __get_event_index(vint_desc, hwirq);
> + event_desc = &vint_desc->events[event_index];
> + mutex_lock(&vint_desc->event_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_index);
> +
> + clear_bit(event_index, 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;
> + mutex_unlock(&vint_desc->event_mutex);
> +
> + /* Free parent irq */
> + if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) ==
> + MAX_EVENTS_PER_VINT)

Single line. Also, how do you ensure that this doesn't race with the
allocation if you're not holding the lock?

> + ti_sci_inta_free_parent_irq(domain, vint_desc);
> +}
> +
> +/**
> + * 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_vint_desc *vint_desc;
> +
> + vint_desc = ti_sci_inta_alloc_irq(data->domain, data->hwirq);
> + if (IS_ERR(vint_desc))
> + return PTR_ERR(vint_desc);
> +
> + data->chip_data = vint_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_vint_desc *vint_desc;
> +
> + vint_desc = irq_data_get_irq_chip_data(data);
> + ti_sci_inta_free_irq(data->domain, vint_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_vint_desc *vint_desc;
> + struct ti_sci_inta_irq_domain *inta;
> + int event_index;
> +
> + vint_desc = irq_data_get_irq_chip_data(data);
> + inta = data->domain->host_data;
> + event_index = __get_event_index(vint_desc, data->hwirq);
> + if (event_index < 0)
> + return;
> +
> + writeq_relaxed(BIT(event_index), 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)
> +{
> + __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)
> +{
> + struct irq_desc *desc = irq_to_desc(data->irq);
> +
> + /*
> + * .alloc default sets handle_edge_irq. But if the user specifies
> + * that IRQ is level MSI, then update the handle to handle_level_irq
> + */
> + if (type & IRQF_TRIGGER_HIGH)
> + desc->handle_irq = handle_level_irq;
> +
> + return 0;

How about invalid values?

> +}
> +
> +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_ack = ti_sci_inta_ack_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,
> + .irq_set_type = ti_sci_inta_set_type,
> +};
> +
> +/**
> + * 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 = {
> + .alloc = ti_sci_inta_irq_domain_alloc,
> + .free = ti_sci_inta_irq_domain_free,
> +};
> +
> +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");
>

The biggest things to fix here is the hwirq thing, which I believe would
simplify the locking a bit.

Thanks,

M.
--
Jazz is not dead. It just smells funny...