by Hanjun Guo

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Subject: Re: [PATCH v3 11/14] ACPI: irq: introduce interrupt producer

Hi Aleksey,

On 2016/12/1 19:12, Aleksey Makarov wrote:
>
> Hi Hanjun,
>
> On 10/25/2016 09:09 PM, Hanjun Guo wrote:
>> From: Hanjun Guo <[email protected]>
>>
>> In ACPI 6.1 spec, section 19.6.62, Interrupt Resource Descriptor Macro,
>
> [ ... ]
>
>> ---
>> drivers/acpi/gsi.c | 10 ++++--
>> drivers/acpi/resource.c | 85
>> ++++++++++++++++++++++++++++++++++---------------
>> include/acpi/acpi_bus.h | 1 +
>> 3 files changed, 68 insertions(+), 28 deletions(-)
>>
>> diff --git a/drivers/acpi/gsi.c b/drivers/acpi/gsi.c
>> index ee9e0f2..29ee547 100644
>> --- a/drivers/acpi/gsi.c
>> +++ b/drivers/acpi/gsi.c
>> @@ -55,13 +55,19 @@ int acpi_register_gsi(struct device *dev, u32 gsi,
>> int trigger,
>> int polarity)
>> {
>> struct irq_fwspec fwspec;
>> + struct acpi_device *adev = dev ? to_acpi_device(dev) : NULL;
>
> Why are you sure dev is always an acpi device?
> Look for example at drivers/acpi/pci_irq.c:377 where this function
> is called for a PCI device

Good catch, but I will drop this patch and use Agustin's one [1].

[1]: https://mail-archive.com/[email protected]/msg1283116.html

Thanks
Hanjun

2016-12-03 12:18:25

by Graeme Gregory

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Subject: Re: [PATCH v3 11/14] ACPI: irq: introduce interrupt producer

On Tue, Oct 25, 2016 at 11:09:26PM +0800, Hanjun Guo wrote:
> From: Hanjun Guo <[email protected]>
>
> In ACPI 6.1 spec, section 19.6.62, Interrupt Resource Descriptor Macro,
>
> Interrupt (ResourceUsage, EdgeLevel, ActiveLevel, Shared,
> ResourceSourceIndex, ResourceSource, DescriptorName)
> { InterruptList } => Buffer
>
> For the arguement ResourceUsage and DescriptorName, which means:
>
> ResourceUsage describes whether the device consumes the specified
> interrupt ( ResourceConsumer ) or produces it for use by a child
> device ( ResourceProducer ).
> If nothing is specified, then ResourceConsumer is assumed.
>
> DescriptorName evaluates to a name string which refers to the
> entire resource descriptor.
>
> So it can be used for devices connecting to a specific interrupt
> prodcucer instead of the main interrupt controller in MADT. In the
> real world, we have irqchip such as mbi-gen which connecting to
> a group of wired interrupts and then issue msi to the ITS, devices
> connecting to such interrupt controller fit this scope.
>
> For now the irq for ACPI only pointer to the main interrupt
> controller's irqdomain, for devices not connecting to those
> irqdomains, which need to present its irq parent, we can use
> following ASL code to represent it:
>
> Interrupt(ResourceConsumer,..., "\_SB.IRQP") {12,14,....}
>
> then we can parse the interrupt producer with the full
> path name "\_SB.IRQP".
>
> In order to do that, we introduce a pointer interrupt_producer
> in struct acpi_device, and fill it when scanning irq resources
> for acpi device if it specifies the interrupt producer.
>
> But for now when parsing the resources for acpi devices, we don't
> pass the acpi device for acpi_walk_resoures() in drivers/acpi/resource.c,
> so introduce a adev in struct res_proc_context to pass it as a context
> to scan the interrupt resources, then finally pass to acpi_register_gsi()
> to find its interrupt producer to get the virq from diffrent domains.
>
> With steps above ready, rework acpi_register_gsi() to get other
> interrupt producer if devices not connecting to main interrupt
> controller.
>
> Since we often pass NULL to acpi_register_gsi() and there is no interrupt
> producer for devices connect to gicd on ARM or io-apic on X86, so it will
> use the default irqdomain for those deivces and no functional changes to
> those devices.
>
> Signed-off-by: Hanjun Guo <[email protected]>
> Cc: Rafael J. Wysocki <[email protected]>
> Cc: Marc Zyngier <[email protected]>
> Cc: Agustin Vega-Frias <[email protected]>
> Cc: Lorenzo Pieralisi <[email protected]>
> ---
> drivers/acpi/gsi.c | 10 ++++--
> drivers/acpi/resource.c | 85 ++++++++++++++++++++++++++++++++++---------------
> include/acpi/acpi_bus.h | 1 +
> 3 files changed, 68 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/acpi/gsi.c b/drivers/acpi/gsi.c
> index ee9e0f2..29ee547 100644
> --- a/drivers/acpi/gsi.c
> +++ b/drivers/acpi/gsi.c
> @@ -55,13 +55,19 @@ int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
> int polarity)
> {
> struct irq_fwspec fwspec;
> + struct acpi_device *adev = dev ? to_acpi_device(dev) : NULL;
>
> - if (WARN_ON(!acpi_gsi_domain_id)) {
> + if (adev && &adev->fwnode && adev->interrupt_producer)
> + /* devices in DSDT connecting to spefic interrupt producer */
> + fwspec.fwnode = adev->interrupt_producer;
> + else if (acpi_gsi_domain_id)
> + /* devices connecting to gicd in default */
> + fwspec.fwnode = acpi_gsi_domain_id;
> + else {
> pr_warn("GSI: No registered irqchip, giving up\n");
> return -EINVAL;
> }
>
> - fwspec.fwnode = acpi_gsi_domain_id;
> fwspec.param[0] = gsi;
> fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
> fwspec.param_count = 2;
> diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
> index 56241eb..f1371cf 100644
> --- a/drivers/acpi/resource.c
> +++ b/drivers/acpi/resource.c
> @@ -381,7 +381,7 @@ 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 acpi_device *adev, struct resource *res, u32 gsi,
> u8 triggering, u8 polarity, u8 shareable,
> bool legacy)
> {
> @@ -415,7 +415,7 @@ 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);
> + irq = acpi_register_gsi(&adev->dev, gsi, triggering, polarity);
> if (irq >= 0) {
> res->start = irq;
> res->end = irq;
> @@ -424,27 +424,9 @@ static void acpi_dev_get_irqresource(struct resource *res, u32 gsi,
> }
> }
>
> -/**
> - * acpi_dev_resource_interrupt - Extract ACPI interrupt resource information.
> - * @ares: Input ACPI resource object.
> - * @index: Index into the array of GSIs represented by the resource.
> - * @res: Output generic resource object.
> - *
> - * Check if the given ACPI resource object represents an interrupt resource
> - * and @index does not exceed the resource's interrupt count (true is returned
> - * in that case regardless of the results of the other checks)). If that's the
> - * case, register the GSI corresponding to @index from the array of interrupts
> - * represented by the resource and populate the generic resource object pointed
> - * to by @res accordingly. If the registration of the GSI is not successful,
> - * IORESOURCE_DISABLED will be set it that object's flags.
> - *
> - * Return:
> - * 1) false with res->flags setting to zero: not the expected resource type
> - * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
> - * 3) true: valid assigned resource
> - */
> -bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> - struct resource *res)
> +static bool __acpi_dev_resource_interrupt(struct acpi_device *adev,
> + struct acpi_resource *ares, int index,
> + struct resource *res)
> {
> struct acpi_resource_irq *irq;
> struct acpi_resource_extended_irq *ext_irq;
> @@ -460,7 +442,7 @@ 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(adev, res, irq->interrupts[index],
> irq->triggering, irq->polarity,
> irq->sharable, true);
> break;
> @@ -470,7 +452,31 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> acpi_dev_irqresource_disabled(res, 0);
> return false;
> }
> - acpi_dev_get_irqresource(res, ext_irq->interrupts[index],
> +
> + /*
> + * It's a interrupt consumer device and connecting to specfic
> + * interrupt controller. For now, we only support connecting
> + * interrupts to one irq controller for a single device
> + */
> + if (ext_irq->producer_consumer == ACPI_CONSUMER
> + && ext_irq->resource_source.string_length != 0
> + && !adev->interrupt_producer) {
> + acpi_status status;
> + acpi_handle handle;
> + struct acpi_device *device;
> +
> + status = acpi_get_handle(NULL, ext_irq->resource_source.string_ptr, &handle);
> + if (ACPI_FAILURE(status))
> + return false;
> +
> + device = acpi_bus_get_acpi_device(handle);
> + if (!device)
> + return false;
> +
> + adev->interrupt_producer = &device->fwnode;
> + }
> +
> + acpi_dev_get_irqresource(adev, res, ext_irq->interrupts[index],
> ext_irq->triggering, ext_irq->polarity,
> ext_irq->sharable, false);
> break;
> @@ -481,6 +487,31 @@ bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
>
> return true;
> }
> +
> +/**
> + * acpi_dev_resource_interrupt - Extract ACPI interrupt resource information.
> + * @ares: Input ACPI resource object.
> + * @index: Index into the array of GSIs represented by the resource.
> + * @res: Output generic resource object.
> + *
> + * Check if the given ACPI resource object represents an interrupt resource
> + * and @index does not exceed the resource's interrupt count (true is returned
> + * in that case regardless of the results of the other checks)). If that's the
> + * case, register the GSI corresponding to @index from the array of interrupts
> + * represented by the resource and populate the generic resource object pointed
> + * to by @res accordingly. If the registration of the GSI is not successful,
> + * IORESOURCE_DISABLED will be set it that object's flags.
> + *
> + * Return:
> + * 1) false with res->flags setting to zero: not the expected resource type
> + * 2) false with IORESOURCE_DISABLED in res->flags: valid unassigned resource
> + * 3) true: valid assigned resource
> + */
> +bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
> + struct resource *res)
> +{
> + return __acpi_dev_resource_interrupt(NULL, ares, index, res);
> +}
> EXPORT_SYMBOL_GPL(acpi_dev_resource_interrupt);

You cannot do this as &adev->dev is deferenced in acpi_dev_get_irqresource
without a check that adev is NULL, and so passes an offset from NULL to
acpi_register_gsi() which breaks everything.

Graeme

>
> /**
> @@ -499,6 +530,7 @@ struct res_proc_context {
> void *preproc_data;
> int count;
> int error;
> + struct acpi_device *adev;
> };
>
> static acpi_status acpi_dev_new_resource_entry(struct resource_win *win,
> @@ -546,7 +578,7 @@ static acpi_status acpi_dev_process_resource(struct acpi_resource *ares,
> || acpi_dev_resource_ext_address_space(ares, &win))
> return acpi_dev_new_resource_entry(&win, c);
>
> - for (i = 0; acpi_dev_resource_interrupt(ares, i, res); i++) {
> + for (i = 0; __acpi_dev_resource_interrupt(c->adev, ares, i, res); i++) {
> acpi_status status;
>
> status = acpi_dev_new_resource_entry(&win, c);
> @@ -599,6 +631,7 @@ int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
> c.preproc_data = preproc_data;
> c.count = 0;
> c.error = 0;
> + c.adev = adev;
> status = acpi_walk_resources(adev->handle, METHOD_NAME__CRS,
> acpi_dev_process_resource, &c);
> if (ACPI_FAILURE(status)) {
> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> index 4242c31..5410d3b 100644
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -355,6 +355,7 @@ struct acpi_device {
> int device_type;
> acpi_handle handle; /* no handle for fixed hardware */
> struct fwnode_handle fwnode;
> + struct fwnode_handle *interrupt_producer;
> struct acpi_device *parent;
> struct list_head children;
> struct list_head node;
> --
> 1.7.12.4
>