Hi Agustin,
On Tue, Oct 18, 2016 at 01:41:48PM -0400, Agustin Vega-Frias 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 | 141 ++++++++++++++++++++++++++++++++++++++
> drivers/acpi/resource.c | 21 +++---
> include/asm-generic/vmlinux.lds.h | 1 +
> include/linux/acpi.h | 71 +++++++++++++++++++
> include/linux/irqchip.h | 17 ++++-
> 6 files changed, 240 insertions(+), 12 deletions(-)
> create mode 100644 drivers/acpi/irqdomain.c
>
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 9ed0878..880401b 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -57,6 +57,7 @@ acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
> acpi-y += acpi_lpat.o
> acpi-$(CONFIG_ACPI_GENERIC_GSI) += gsi.o
> acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o
> +acpi-$(CONFIG_IRQ_DOMAIN) += 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..c53b9f4
> --- /dev/null
> +++ b/drivers/acpi/irqdomain.c
> @@ -0,0 +1,141 @@
> +/*
> + * 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_ensure_probed() - Check if the device has registered
> + * an IRQ domain and probe as necessary
> + *
> + * @device: Device to check and probe
> + *
> + * Returns: 0 on success, -ENODEV otherwise
This is not correct (ie it depends on what
struct acpi_dsdt_probe_entry.probe
returns) and I would like to take this nit as an opportunity
to take a step back and ask you a question below.
> + */
> +static int acpi_irq_domain_ensure_probed(struct acpi_device *device)
> +{
> + struct acpi_dsdt_probe_entry *entry;
> +
> + if (irq_find_matching_fwnode(&device->fwnode, DOMAIN_BUS_ANY) != 0)
> + return 0;
> +
> + for (entry = &__dsdt_acpi_probe_table;
> + entry < &__dsdt_acpi_probe_table_end; entry++)
> + if (strcmp(entry->_hid, acpi_device_hid(device)) == 0)
> + return entry->probe(device);
Through this approch we are forcing an irqchip (that by the way it
has a physical node ACPI companion by being a DSDT device object so it
could be managed by a platform driver) to be probed. The question is: is
there a reason (apart from the current ACPI resource parsing API) why
this can't be implemented through deferred probing and the device
dependencies framework Rafael is working on:
http://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1246897.html
The DT layer, through the of_irq_get() API, supports probe deferral
and what I am asking you is if there is any blocking point (again,
apart from the current ACPI API) to implement the same mechanism.
I have not reviewed the previous versions so I am certainly missing
some of the bits and pieces already discussed, apologies for that.
Thanks,
Lorenzo
> +
> + return -ENODEV;
> +}
> +
> +/**
> + * 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
> + * @hwirq: Hardware IRQ number
> + * @trigger: trigger type of the IRQ number to be mapped
> + * @polarity: polarity of the IRQ to be mapped
> + *
> + * 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(const struct acpi_resource_source *source,
> + u32 hwirq, int trigger, int polarity)
> +{
> + struct irq_fwspec fwspec;
> + struct acpi_device *device;
> + acpi_handle handle;
> + acpi_status status;
> + int ret;
> +
> + /* An empty acpi_resource_source means it is a GSI */
> + if (!source->string_length)
> + return acpi_register_gsi(NULL, hwirq, trigger, polarity);
> +
> + 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;
> +
> + ret = acpi_irq_domain_ensure_probed(device);
> + if (ret)
> + goto out_put_device;
> +
> + fwspec.fwnode = &device->fwnode;
> + fwspec.param[0] = hwirq;
> + fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
> + fwspec.param_count = 2;
> +
> + ret = irq_create_fwspec_mapping(&fwspec);
> +
> +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
> + * @hwirq: Hardware 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(const struct acpi_resource_source *source,
> + u32 hwirq)
> +{
> + struct irq_domain *domain;
> + struct acpi_device *device;
> + acpi_handle handle;
> + acpi_status status;
> + int ret = 0;
> +
> + if (!source->string_length) {
> + acpi_unregister_gsi(hwirq);
> + return 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, hwirq));
> +
> +out_put_device:
> + acpi_bus_put_acpi_device(device);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(acpi_irq_domain_unregister_irq);
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index 56241eb..3fb7abf 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 hwirq,
> + const 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(hwirq)) {
> + acpi_dev_irqresource_disabled(res, hwirq);
> return;
> }
>
> @@ -402,25 +403,25 @@ 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(hwirq, &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,
> - t ? "level" : "edge", p ? "low" : "high");
> + pr_warn("ACPI: IRQ %d override to %s, %s\n", hwirq,
> + t ? "level" : "edge", p ? "low" : "high");
> triggering = trig;
> polarity = pol;
> }
> }
>
> res->flags = acpi_dev_irq_flags(triggering, polarity, shareable);
> - irq = acpi_register_gsi(NULL, gsi, triggering, polarity);
> + irq = acpi_irq_domain_register_irq(source, hwirq, triggering, polarity);
> if (irq >= 0) {
> res->start = irq;
> res->end = irq;
> } else {
> - acpi_dev_irqresource_disabled(res, gsi);
> + acpi_dev_irqresource_disabled(res, hwirq);
> }
> }
>
> @@ -446,6 +447,7 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
> bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> struct resource *res)
> {
> + const struct acpi_resource_source dummy = { 0, 0, NULL };
> struct acpi_resource_irq *irq;
> struct acpi_resource_extended_irq *ext_irq;
>
> @@ -460,7 +462,7 @@ 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 +473,7 @@ 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/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
> index 3074796..f808afdc 100644
> --- a/include/asm-generic/vmlinux.lds.h
> +++ b/include/asm-generic/vmlinux.lds.h
> @@ -563,6 +563,7 @@
> IRQCHIP_OF_MATCH_TABLE() \
> ACPI_PROBE_TABLE(irqchip) \
> ACPI_PROBE_TABLE(clksrc) \
> + ACPI_PROBE_TABLE(dsdt) \
> EARLYCON_TABLE()
>
> #define INIT_TEXT \
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index ddbeda6..bb1a838 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
> @@ -321,6 +322,31 @@ void acpi_set_irq_model(enum acpi_irq_model_id model,
> */
> void acpi_unregister_gsi (u32 gsi);
>
> +#ifdef CONFIG_IRQ_DOMAIN
> +
> +int acpi_irq_domain_register_irq(const struct acpi_resource_source *source,
> + u32 hwirq, int trigger, int polarity);
> +int acpi_irq_domain_unregister_irq(const struct acpi_resource_source *source,
> + u32 hwirq);
> +
> +#else
> +
> +static inline int acpi_irq_domain_register_irq(
> + const struct acpi_resource_source *source, u32 hwirq, int trigger,
> + int polarity)
> +{
> + return acpi_register_gsi(NULL, hwirq, trigger, polarity);
> +}
> +
> +static inline int acpi_irq_domain_unregister_irq(
> + const struct acpi_resource_source *source, u32 hwirq)
> +{
> + acpi_unregister_gsi(hwirq);
> + return 0;
> +}
> +
> +#endif /* CONFIG_IRQ_DOMAIN */
> +
> struct pci_dev;
>
> int acpi_pci_irq_enable (struct pci_dev *dev);
> @@ -1024,6 +1050,34 @@ struct acpi_probe_entry {
> (&ACPI_PROBE_TABLE_END(t) - \
> &ACPI_PROBE_TABLE(t))); \
> })
> +
> +/* Length of Hardware ID field in DSDT entries as per ACPI spec */
> +#define ACPI_HID_LEN 9
> +
> +typedef int (*acpi_dsdt_handler)(struct acpi_device *);
> +
> +/**
> + * struct acpi_probe_dsdt_entry - boot-time probing entry for DSDT devices
> + * @hid: _HID of the device
> + * @fn: Callback to the driver being probed
> + * @driver_data: Sideband data provided back to the driver
> + */
> +struct acpi_dsdt_probe_entry {
> + __u8 _hid[ACPI_HID_LEN];
> + acpi_dsdt_handler probe;
> +};
> +
> +#define ACPI_DECLARE_DSDT_PROBE_ENTRY(name, hid, fn) \
> + static const struct acpi_dsdt_probe_entry __acpi_probe_##name \
> + __used __section(__dsdt_acpi_probe_table) = \
> + { \
> + ._hid = hid, \
> + .probe = fn, \
> + }
> +
> +extern struct acpi_dsdt_probe_entry __dsdt_acpi_probe_table;
> +extern struct acpi_dsdt_probe_entry __dsdt_acpi_probe_table_end;
> +
> #else
> static inline int acpi_dev_get_property(struct acpi_device *adev,
> const char *name, acpi_object_type type,
> @@ -1101,8 +1155,25 @@ static inline struct fwnode_handle *acpi_get_next_subnode(struct device *dev,
> (void *) data }
>
> #define acpi_probe_device_table(t) ({ int __r = 0; __r;})
> +
> +#define ACPI_DECLARE_DSDT_PROBE_ENTRY(name, hid, fn) \
> + static const void *__acpi_probe_##name[] \
> + __attribute__((unused)) \
> + = { (void *) hid, \
> + (void *) fn }
> +
> #endif
>
> +#define MADT_IRQCHIP_ACPI_DECLARE(name, subtable, validate, data, fn) \
> + ACPI_DECLARE_PROBE_ENTRY(irqchip, name, ACPI_SIG_MADT, \
> + subtable, validate, data, fn)
> +
> +#define DSDT_IRQCHIP_ACPI_DECLARE(name, hid, fn) \
> + ACPI_DECLARE_DSDT_PROBE_ENTRY(name, hid, fn)
> +
> +#define __IRQCHIP_ACPI_DECLARE(_a1, _a2, _a3, _a4, _a5, type, ...) \
> + type##_IRQCHIP_ACPI_DECLARE
> +
> #ifdef CONFIG_ACPI_TABLE_UPGRADE
> void acpi_table_upgrade(void);
> #else
> diff --git a/include/linux/irqchip.h b/include/linux/irqchip.h
> index 89c34b2..c2d0c12 100644
> --- a/include/linux/irqchip.h
> +++ b/include/linux/irqchip.h
> @@ -29,6 +29,10 @@
> /*
> * This macro must be used by the different irqchip drivers to declare
> * the association between their version and their initialization function.
> + * Two syntaxes are supported depending on the table where the irqchip device
> + * is declared:
> + *
> + * - MADT irqchip syntax, which requires the following five arguments:
> *
> * @name: name that must be unique accross all IRQCHIP_ACPI_DECLARE of the
> * same file.
> @@ -37,10 +41,17 @@
> * Can be NULL.
> * @data: data to be checked by the validate function.
> * @fn: initialization function
> + *
> + * - DSDT irqchip syntax, which requires the following three arguments:
> + *
> + * @name: name that must be unique across all IRQCHIP_ACPI_DECLARE of the
> + * same file.
> + * @hid: _HID of the DSDT device
> + * @fn: initialization function
> */
> -#define IRQCHIP_ACPI_DECLARE(name, subtable, validate, data, fn) \
> - ACPI_DECLARE_PROBE_ENTRY(irqchip, name, ACPI_SIG_MADT, \
> - subtable, validate, data, fn)
> +
> +#define IRQCHIP_ACPI_DECLARE(...) \
> + __IRQCHIP_ACPI_DECLARE(__VA_ARGS__, MADT, _unused, DSDT)(__VA_ARGS__)
>
> #ifdef CONFIG_IRQCHIP
> void irqchip_init(void);
> --
> Qualcomm Datacenter Technologies, Inc. on behalf of the Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
>
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