Re: [PATCH V3 1/2] ACPI: Add support for ResourceSource/IRQ domain mapping

From: Marc Zyngier
Date: Sat Jun 04 2016 - 08:30:37 EST

Next message: Marc Zyngier: "Re: [PATCH V3 2/2] irqchip: qcom: Add IRQ combiner driver"
Previous message: Jeff Layton: "Re: Dcache oops"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Fri, 13 May 2016 12:16:42 -0400
Agustin Vega-Frias <agustinv@xxxxxxxxxxxxxx> wrote:

> This allows irqchip drivers to associate an ACPI DSDT device to
> an IRQ domain and provides support for using the ResourceSource
> in Extended IRQ Resources to find the domain and map the IRQs
> specified on that domain.
>
> Signed-off-by: Agustin Vega-Frias <agustinv@xxxxxxxxxxxxxx>
> ---
> drivers/acpi/Makefile | 1 +
> drivers/acpi/irqdomain.c | 108 +++++++++++++++++++++++++++++++++++++++++++++++
> drivers/acpi/resource.c | 23 ++++++----
> include/linux/acpi.h | 6 +++
> 4 files changed, 130 insertions(+), 8 deletions(-)
> create mode 100644 drivers/acpi/irqdomain.c
>
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index b12fa64..79db78f 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -56,6 +56,7 @@ acpi-$(CONFIG_ACPI_NUMA) += numa.o
> acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
> acpi-y += acpi_lpat.o
> acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
> +acpi-y += irqdomain.o
>
> # These are (potentially) separate modules
>
> diff --git a/drivers/acpi/irqdomain.c b/drivers/acpi/irqdomain.c
> new file mode 100644
> index 0000000..0fd10a9
> --- /dev/null
> +++ b/drivers/acpi/irqdomain.c
> @@ -0,0 +1,108 @@
> +/*
> + * ACPI ResourceSource/IRQ domain mapping support
> + *
> + * Copyright (c) 2016, The Linux Foundation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +#include <linux/acpi.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +
> +/**
> + * acpi_irq_domain_register_irq() - Register the mapping for an IRQ produced
> + * by the given acpi_resource_source to a
> + * Linux IRQ number
> + * @source: IRQ source

I'm a bit uncertain if this describe the interrupt producer (the device
that shakes an interrupt line) or the interrupt collator (the device
that presents a bunch of interrupts to a downstream element). I'm
tempted to say that this is the latter, but that's far from being clear.

> + * @rcirq: IRQ number
> + * @trigger: trigger type of the IRQ number to be mapped
> + * @polarity: polarity of the IRQ to be mapped

So if I'm right in my above understanding, you've reinvented an
existing abstraction (irq_fwspec).

> + *
> + * Returns: a valid linux IRQ number on success
> + * -ENODEV if the given acpi_resource_source cannot be found
> + * -EPROBE_DEFER if the IRQ domain has not been registered
> + * -EINVAL for all other errors
> + */
> +int acpi_irq_domain_register_irq(struct acpi_resource_source *source, u32 rcirq,
> + int trigger, int polarity)
> +{
> + struct irq_domain *domain;
> + struct acpi_device *device;
> + acpi_handle handle;
> + acpi_status status;
> + unsigned int type;
> + int ret;
> +
> + status = acpi_get_handle(NULL, source->string_ptr, &handle);
> + if (ACPI_FAILURE(status))
> + return -ENODEV;
> +
> + device = acpi_bus_get_acpi_device(handle);
> + if (!device)
> + return -ENODEV;
> +

So at this point, you should be able to create a irq_fwspec, and call
into irq_create_fwspec_mapping(), without the need to open-code stuff
we already have. And as a bonus point, you'd end-up with code that'd be
similar to what is in gsi.c...

> + domain = irq_find_matching_fwnode(&device->fwnode, DOMAIN_BUS_ANY);
> + if (!domain) {
> + ret = -EPROBE_DEFER;
> + goto out_put_device;
> + }
> +
> + type = acpi_dev_get_irq_type(trigger, polarity);
> + ret = irq_create_mapping(domain, rcirq);
> + if (ret)
> + irq_set_irq_type(ret, type);
> +
> +out_put_device:
> + acpi_bus_put_acpi_device(device);
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(acpi_irq_domain_register_irq);
> +
> +/**
> + * acpi_irq_domain_unregister_irq() - Delete the mapping for an IRQ produced
> + * by the given acpi_resource_source to a
> + * Linux IRQ number
> + * @source: IRQ source
> + * @rcirq: IRQ number
> + *
> + * Returns: 0 on success
> + * -ENODEV if the given acpi_resource_source cannot be found
> + * -EINVAL for all other errors
> + */
> +int acpi_irq_domain_unregister_irq(struct acpi_resource_source *source,
> + u32 rcirq)
> +{
> + struct irq_domain *domain;
> + struct acpi_device *device;
> + acpi_handle handle;
> + acpi_status status;
> + int ret = 0;
> +
> + status = acpi_get_handle(NULL, source->string_ptr, &handle);
> + if (ACPI_FAILURE(status))
> + return -ENODEV;
> +
> + device = acpi_bus_get_acpi_device(handle);
> + if (!device)
> + return -ENODEV;
> +
> + domain = irq_find_matching_fwnode(&device->fwnode, DOMAIN_BUS_ANY);
> + if (!domain) {
> + ret = -EINVAL;
> + goto out_put_device;
> + }
> +
> + irq_dispose_mapping(irq_find_mapping(domain, rcirq));
> +
> +out_put_device:
> + acpi_bus_put_acpi_device(device);
> + return ret;
> +}

Again, this smell a lot like gsi.c, with added sugar on top.

> +EXPORT_SYMBOL_GPL(acpi_irq_domain_unregister_irq);
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index 56241eb..1551698 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -381,14 +381,15 @@ static void acpi_dev_irqresource_disabled(struct resource *res, u32 gsi)
> res->flags = IORESOURCE_IRQ | IORESOURCE_DISABLED | IORESOURCE_UNSET;
> }
>
> -static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
> +static void acpi_dev_get_irqresource(struct resource *res, u32 rcirq,
> + struct acpi_resource_source *source,
> u8 triggering, u8 polarity, u8 shareable,
> bool legacy)
> {
> int irq, p, t;
>
> - if (!valid_IRQ(gsi)) {
> - acpi_dev_irqresource_disabled(res, gsi);
> + if ((source->string_length == 0) && !valid_IRQ(rcirq)) {
> + acpi_dev_irqresource_disabled(res, rcirq);
> return;
> }
>
> @@ -402,12 +403,12 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
> * using extended IRQ descriptors we take the IRQ configuration
> * from _CRS directly.
> */
> - if (legacy && !acpi_get_override_irq(gsi, &t, &p)) {
> + if (legacy && !acpi_get_override_irq(rcirq, &t, &p)) {
> u8 trig = t ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
> u8 pol = p ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
>
> if (triggering != trig || polarity != pol) {
> - pr_warning("ACPI: IRQ %d override to %s, %s\n", gsi,
> + pr_warning("ACPI: IRQ %d override to %s, %s\n", rcirq,
> t ? "level" : "edge", p ? "low" : "high");
> triggering = trig;
> polarity = pol;
> @@ -415,12 +416,16 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
> }
>
> res->flags = acpi_dev_irq_flags(triggering, polarity, shareable);
> - irq = acpi_register_gsi(NULL, gsi, triggering, polarity);
> + if (source->string_length > 0)
> + irq = acpi_irq_domain_register_irq(source, rcirq, triggering,
> + polarity);
> + else
> + irq = acpi_register_gsi(NULL, rcirq, triggering, polarity);

Do you see what I mean about these being similar?

> if (irq >= 0) {
> res->start = irq;
> res->end = irq;
> } else {
> - acpi_dev_irqresource_disabled(res, gsi);
> + acpi_dev_irqresource_disabled(res, rcirq);
> }
> }
>
> @@ -448,6 +453,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> {
> struct acpi_resource_irq *irq;
> struct acpi_resource_extended_irq *ext_irq;
> + struct acpi_resource_source dummy = { 0, 0, NULL };
>
> switch (ares->type) {
> case ACPI_RESOURCE_TYPE_IRQ:
> @@ -460,7 +466,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> acpi_dev_irqresource_disabled(res, 0);
> return false;
> }
> - acpi_dev_get_irqresource(res, irq->interrupts[index],
> + acpi_dev_get_irqresource(res, irq->interrupts[index], &dummy,
> irq->triggering, irq->polarity,
> irq->sharable, true);
> break;
> @@ -471,6 +477,7 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> return false;
> }
> acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> + &ext_irq->resource_source,
> ext_irq->triggering, ext_irq->polarity,
> ext_irq->sharable, false);
> break;
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 06ed7e5..f4f515e 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -26,6 +26,7 @@
> #include <linux/resource_ext.h>
> #include <linux/device.h>
> #include <linux/property.h>
> +#include <linux/irqdomain.h>
>
> #ifndef _LINUX
> #define _LINUX
> @@ -294,6 +295,11 @@ int acpi_isa_irq_to_gsi (unsigned isa_irq, u32 *gsi);
> void acpi_set_irq_model(enum acpi_irq_model_id model,
> struct fwnode_handle *fwnode);
>
> +int acpi_irq_domain_register_irq(struct acpi_resource_source *source, u32 rcirq,
> + int trigger, int polarity);
> +int acpi_irq_domain_unregister_irq(struct acpi_resource_source *source,
> + u32 rcirq);
> +
> #ifdef CONFIG_X86_IO_APIC
> extern int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity);
> #else

Thanks,

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

Next message: Marc Zyngier: "Re: [PATCH V3 2/2] irqchip: qcom: Add IRQ combiner driver"
Previous message: Jeff Layton: "Re: Dcache oops"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]