| Message ID | 1414484803-10311-2-git-send-email-jiang.liu@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Jiang, On Tue, 2014-10-28 at 16:26 +0800, Jiang Liu wrote: <deleted...> > @@ -471,7 +469,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) > struct irq_domain *domain; > irq_hw_number_t hwirq; > unsigned int type = IRQ_TYPE_NONE; > - unsigned int virq; > + int virq; > > domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain; > if (!domain) { > @@ -480,6 +478,11 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) > return 0; > } > > + if (irq_domain_is_hierarchy(domain)) { > + virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data); > + return virq <= 0 ? 0 : virq; > + } > + > /* If domain has no translation, then we assume interrupt line */ > if (domain->ops->xlate == NULL) > hwirq = irq_data->args[0]; > @@ -540,8 +543,8 @@ unsigned int irq_find_mapping(struct irq_domain *domain, > return 0; > > if (hwirq < domain->revmap_direct_max_irq) { > - data = irq_get_irq_data(hwirq); > - if (data && (data->domain == domain) && (data->hwirq == hwirq)) > + data = irq_domain_get_irq_data(domain, hwirq); > + if (data && data->hwirq == hwirq) > return hwirq; > } Why do you want to move irq_domain_alloc_irqs up there? On the ARM side, the irqchips will be different on different SoCs, so we will need to implement irq_find_mapping check and set_type in several different location. This leads to code duplication. It is preferred to do these in general code [1], [2] Is it acceptable if we do irq_find_mapping and set_type here like [3]? [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/294294.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/294306.html [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/296543.html Joe.C > > @@ -709,3 +712,341 @@ const struct irq_domain_ops irq_domain_simple_ops = { > .xlate = irq_domain_xlate_onetwocell, > }; > EXPORT_SYMBOL_GPL(irq_domain_simple_ops); > + > +static int irq_domain_alloc_descs(int virq, unsigned int cnt, > + irq_hw_number_t hwirq, int node) > +{ > + unsigned int hint; > + > + if (virq >= 0) { > + virq = irq_alloc_descs(virq, virq, cnt, node); > + } else { > + hint = hwirq % nr_irqs; > + if (hint == 0) > + hint++; > + virq = irq_alloc_descs_from(hint, cnt, node); > + if (virq <= 0 && hint > 1) > + virq = irq_alloc_descs_from(1, cnt, node); > + } > + > + return virq; > +} > + > +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY > +static void irq_domain_insert_irq(int virq) > +{ > + struct irq_data *data; > + > + for (data = irq_get_irq_data(virq); data; data = data->parent_data) { > + struct irq_domain *domain = data->domain; > + irq_hw_number_t hwirq = data->hwirq; > + > + if (hwirq < domain->revmap_size) { > + domain->linear_revmap[hwirq] = virq; > + } else { > + mutex_lock(&revmap_trees_mutex); > + radix_tree_insert(&domain->revmap_tree, hwirq, data); > + mutex_unlock(&revmap_trees_mutex); > + } > + > + /* If not already assigned, give the domain the chip's name */ > + if (!domain->name && data->chip) > + domain->name = data->chip->name; > + } > + > + irq_clear_status_flags(virq, IRQ_NOREQUEST); > +} > + > +static void irq_domain_remove_irq(int virq) > +{ > + struct irq_data *data; > + > + irq_set_status_flags(virq, IRQ_NOREQUEST); > + irq_set_chip_and_handler(virq, NULL, NULL); > + synchronize_irq(virq); > + smp_mb(); > + > + for (data = irq_get_irq_data(virq); data; data = data->parent_data) { > + struct irq_domain *domain = data->domain; > + irq_hw_number_t hwirq = data->hwirq; > + > + if (hwirq < domain->revmap_size) { > + domain->linear_revmap[hwirq] = 0; > + } else { > + mutex_lock(&revmap_trees_mutex); > + radix_tree_delete(&domain->revmap_tree, hwirq); > + mutex_unlock(&revmap_trees_mutex); > + } > + } > +} > + > +static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain, > + struct irq_data *child) > +{ > + struct irq_data *irq_data; > + > + irq_data = kzalloc_node(sizeof(*irq_data), GFP_KERNEL, child->node); > + if (irq_data) { > + child->parent_data = irq_data; > + irq_data->irq = child->irq; > + irq_data->node = child->node; > + irq_data->domain = domain; > + } > + > + return irq_data; > +} > + > +static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs) > +{ > + int i; > + struct irq_data *irq_data, *tmp; > + > + for (i = 0; i < nr_irqs; i++) { > + irq_data = irq_get_irq_data(virq + i); > + tmp = irq_data->parent_data; > + irq_data->parent_data = NULL; > + irq_data->domain = NULL; > + > + while (tmp) { > + irq_data = tmp; > + tmp = tmp->parent_data; > + kfree(irq_data); > + } > + } > +} > + > +static int irq_domain_alloc_irq_data(struct irq_domain *domain, > + unsigned int virq, unsigned int nr_irqs) > +{ > + int i; > + struct irq_data *irq_data; > + struct irq_domain *parent; > + > + /* The outermost irq_data is embedded in struct irq_desc */ > + for (i = 0; i < nr_irqs; i++) { > + irq_data = irq_get_irq_data(virq + i); > + irq_data->domain = domain; > + > + for (parent = domain->parent; parent; parent = parent->parent) { > + irq_data = irq_domain_insert_irq_data(parent, irq_data); > + if (!irq_data) { > + irq_domain_free_irq_data(virq, i + 1); > + return -ENOMEM; > + } > + } > + } > + > + return 0; > +} > + > +/** > + * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain > + * @domain: domain to match > + * @virq: IRQ number to get irq_data > + */ > +struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, > + unsigned int virq) > +{ > + struct irq_data *irq_data; > + > + for (irq_data = irq_get_irq_data(virq); irq_data; > + irq_data = irq_data->parent_data) > + if (irq_data->domain == domain) > + return irq_data; > + > + return NULL; > +} > + > +int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, unsigned int virq, > + irq_hw_number_t hwirq, struct irq_chip *chip, > + void *chip_data) > +{ > + struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq); > + > + if (!irq_data) > + return -ENOENT; > + > + irq_data->hwirq = hwirq; > + irq_data->chip = chip ? chip : &no_irq_chip; > + irq_data->chip_data = chip_data; > + > + return 0; > +} > + > +void irq_domain_reset_irq_data(struct irq_data *irq_data) > +{ > + irq_data->hwirq = 0; > + irq_data->chip = &no_irq_chip; > + irq_data->chip_data = NULL; > +} > + > +/** > + * __irq_domain_alloc_irqs - Allocate IRQs from domain > + * @domain: domain to allocate from > + * @irq_base: allocate specified IRQ nubmer if irq_base >= 0 > + * @nr_irqs: number of IRQs to allocate > + * @node: NUMA node id for memory allocation > + * @arg: domain specific argument > + * @realloc: IRQ descriptors have already been allocated if true > + * > + * Allocate IRQ numbers and initialized all data structures to support > + * hiearchy IRQ domains. > + * Parameter @realloc is mainly to support legacy IRQs. > + * Returns error code or allocated IRQ number > + * > + * The whole process to setup an IRQ has been split into two steps. > + * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ > + * descriptor and required hardware resources. The second step, > + * irq_domain_activate_irq(), is to program hardwares with preallocated > + * resources. In this way, it's easier to rollback when failing to > + * allocate resources. > + */ > +int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, > + unsigned int nr_irqs, int node, void *arg, > + bool realloc) > +{ > + int i, ret, virq; > + > + if (domain == NULL) { > + domain = irq_default_domain; > + if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n")) > + return -EINVAL; > + } > + > + if (!domain->ops->alloc) { > + pr_debug("domain->ops->alloc() is NULL\n"); > + return -ENOSYS; > + } > + > + if (realloc && irq_base >= 0) { > + virq = irq_base; > + } else { > + virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node); > + if (virq < 0) { > + pr_debug("cannot allocate IRQ(base %d, count %d)\n", > + irq_base, nr_irqs); > + return virq; > + } > + } > + > + if (irq_domain_alloc_irq_data(domain, virq, nr_irqs)) { > + pr_debug("cannot allocate memory for IRQ%d\n", virq); > + ret = -ENOMEM; > + goto out_free_desc; > + } > + > + mutex_lock(&irq_domain_mutex); > + ret = domain->ops->alloc(domain, virq, nr_irqs, arg); > + if (ret < 0) { > + mutex_unlock(&irq_domain_mutex); > + goto out_free_irq_data; > + } > + for (i = 0; i < nr_irqs; i++) > + irq_domain_insert_irq(virq + i); > + mutex_unlock(&irq_domain_mutex); > + > + return virq; > + > +out_free_irq_data: > + irq_domain_free_irq_data(virq, nr_irqs); > +out_free_desc: > + irq_free_descs(virq, nr_irqs); > + return ret; > +} > + > +/** > + * irq_domain_free_irqs - Free IRQ number and associated data structures > + * @virq: base IRQ number > + * @nr_irqs: number of IRQs to free > + */ > +void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs) > +{ > + int i; > + struct irq_data *data = irq_get_irq_data(virq); > + > + if (WARN(!data || !data->domain || !data->domain->ops->free, > + "NULL pointer, cannot free irq\n")) > + return; > + > + mutex_lock(&irq_domain_mutex); > + for (i = 0; i < nr_irqs; i++) > + irq_domain_remove_irq(virq + i); > + data->domain->ops->free(data->domain, virq, nr_irqs); > + mutex_unlock(&irq_domain_mutex); > + > + irq_domain_free_irq_data(virq, nr_irqs); > + irq_free_descs(virq, nr_irqs); > +} > + > +/** > + * irq_domain_activate_irq - Call domain_ops->activate recursively to activate > + * interrupt > + * @irq_data: outermost irq_data associated with interrupt > + * > + * This is the second step to call domain_ops->activate to program interrupt > + * controllers, so the interrupt could actually get delivered. > + */ > +int irq_domain_activate_irq(struct irq_data *irq_data) > +{ > + int ret = 0; > + > + if (irq_data && irq_data->domain) { > + struct irq_domain *domain = irq_data->domain; > + > + if (irq_data->parent_data) > + ret = irq_domain_activate_irq(irq_data->parent_data); > + if (ret == 0 && domain->ops->activate) > + ret = domain->ops->activate(domain, irq_data); > + } > + > + return ret; > +} > + > +/** > + * irq_domain_deactivate_irq - Call domain_ops->deactivate recursively to > + * deactivate interrupt > + * @irq_data: outermost irq_data associated with interrupt > + * > + * It calls domain_ops->deactivate to program interrupt controllers to disable > + * interrupt delivery. > + */ > +int irq_domain_deactivate_irq(struct irq_data *irq_data) > +{ > + int ret = 0; > + > + if (irq_data && irq_data->domain) { > + struct irq_domain *domain = irq_data->domain; > + > + if (domain->ops->deactivate) > + ret = domain->ops->deactivate(domain, irq_data); > + if (ret == 0 && irq_data->parent_data) > + ret = irq_domain_deactivate_irq(irq_data->parent_data); > + } > + > + return ret; > +} > + > +static void irq_domain_check_hierarchy(struct irq_domain *domain) > +{ > + /* Hierarchy irq_domains must implement callback alloc() */ > + if (domain->ops->alloc) > + domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY; > +} > +#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */ > +/** > + * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain > + * @domain: domain to match > + * @virq: IRQ number to get irq_data > + */ > +struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, > + unsigned int virq) > +{ > + struct irq_data *irq_data = irq_get_irq_data(virq); > + > + return (irq_data && irq_data->domain == domain) ? irq_data : NULL; > +} > + > +static void irq_domain_check_hierarchy(struct irq_domain *domain) > +{ > +} > +#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
On Tue, 28 Oct 2014, Yingjoe Chen wrote: > On Tue, 2014-10-28 at 16:26 +0800, Jiang Liu wrote: > <deleted...> > > @@ -471,7 +469,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) > > struct irq_domain *domain; > > irq_hw_number_t hwirq; > > unsigned int type = IRQ_TYPE_NONE; > > - unsigned int virq; > > + int virq; > > > > domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain; > > if (!domain) { > > @@ -480,6 +478,11 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) > > return 0; > > } > > > > + if (irq_domain_is_hierarchy(domain)) { > > + virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data); > > + return virq <= 0 ? 0 : virq; > > + } > > + > > /* If domain has no translation, then we assume interrupt line */ > > if (domain->ops->xlate == NULL) > > hwirq = irq_data->args[0]; > > @@ -540,8 +543,8 @@ unsigned int irq_find_mapping(struct irq_domain *domain, > > return 0; > > > > if (hwirq < domain->revmap_direct_max_irq) { > > - data = irq_get_irq_data(hwirq); > > - if (data && (data->domain == domain) && (data->hwirq == hwirq)) > > + data = irq_domain_get_irq_data(domain, hwirq); > > + if (data && data->hwirq == hwirq) > > return hwirq; > > } > > Why do you want to move irq_domain_alloc_irqs up there? That's the wrong question. The proper question is whether we can move it after the xlate part. I don't see a reason why we cannot do that. Jiang was right not to incorporate your patch to do that simply because we want to keep the history of the evolution of this code. Your patch is an enhancement and it needs to be discussed and applied seperately. So while we are at it: > + if (irq_domain_is_hierarchy(domain)) { > + if (domain->ops->xlate) { > + /* > + * If we've already configured this interrupt, > + * don't do it again, or hell will break loose. > + */ > + virq = irq_find_mapping(domain, hwirq); > + if (virq) > + return virq; I can understand that it is an issue if the mapping exists already, but I have to ask WHY is it correct behaviour to call into that code for an existing mapping. And why would this check only apply if domain->ops->xlate is set? irq_create_mapping() does it unconditionally. > Joe.C > > > > @@ -709,3 +712,341 @@ const struct irq_domain_ops irq_domain_simple_ops = { Please remove the rest of the mail to which you are not answering next time. Thanks, tglx
On 28/10/14 19:37, Thomas Gleixner wrote: > On Tue, 28 Oct 2014, Yingjoe Chen wrote: >> On Tue, 2014-10-28 at 16:26 +0800, Jiang Liu wrote: >> <deleted...> >>> @@ -471,7 +469,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) >>> struct irq_domain *domain; >>> irq_hw_number_t hwirq; >>> unsigned int type = IRQ_TYPE_NONE; >>> - unsigned int virq; >>> + int virq; >>> >>> domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain; >>> if (!domain) { >>> @@ -480,6 +478,11 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) >>> return 0; >>> } >>> >>> + if (irq_domain_is_hierarchy(domain)) { >>> + virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data); >>> + return virq <= 0 ? 0 : virq; >>> + } >>> + >>> /* If domain has no translation, then we assume interrupt line */ >>> if (domain->ops->xlate == NULL) >>> hwirq = irq_data->args[0]; >>> @@ -540,8 +543,8 @@ unsigned int irq_find_mapping(struct irq_domain *domain, >>> return 0; >>> >>> if (hwirq < domain->revmap_direct_max_irq) { >>> - data = irq_get_irq_data(hwirq); >>> - if (data && (data->domain == domain) && (data->hwirq == hwirq)) >>> + data = irq_domain_get_irq_data(domain, hwirq); >>> + if (data && data->hwirq == hwirq) >>> return hwirq; >>> } >> >> Why do you want to move irq_domain_alloc_irqs up there? > > That's the wrong question. The proper question is whether we can move > it after the xlate part. I don't see a reason why we cannot do that. > > Jiang was right not to incorporate your patch to do that simply > because we want to keep the history of the evolution of this > code. Your patch is an enhancement and it needs to be discussed and > applied seperately. > > So while we are at it: > >> + if (irq_domain_is_hierarchy(domain)) { >> + if (domain->ops->xlate) { >> + /* >> + * If we've already configured this interrupt, >> + * don't do it again, or hell will break loose. >> + */ >> + virq = irq_find_mapping(domain, hwirq); >> + if (virq) >> + return virq; > > I can understand that it is an issue if the mapping exists already, > but I have to ask WHY is it correct behaviour to call into that code > for an existing mapping. As I have originally looked at this, I'll answer the question: The generic DT code parses the whole tree, and generates platform devices as it goes. As part of the platform device creation, it populates the IRQ resources, which translates into calling into irq_create_of_mapping(). You could argue that this behaviour is crazy, and I wouldn't disagree. See http://www.spinics.net/lists/devicetree/msg53164.html for more gory details. > And why would this check only apply if domain->ops->xlate is set? > irq_create_mapping() does it unconditionally. My original code used the xlate callback to parse the opaque irq_data, computing hwirq, and I suspect this is a leftover of it. The above code seems to pull hwirq out of thin air, which is probably not the intended behaviour. Joe? Thanks, M.
On Tue, 28 Oct 2014, Marc Zyngier wrote: > On 28/10/14 19:37, Thomas Gleixner wrote: > > So while we are at it: > > > >> + if (irq_domain_is_hierarchy(domain)) { > >> + if (domain->ops->xlate) { > >> + /* > >> + * If we've already configured this interrupt, > >> + * don't do it again, or hell will break loose. > >> + */ > >> + virq = irq_find_mapping(domain, hwirq); > >> + if (virq) > >> + return virq; > > > > I can understand that it is an issue if the mapping exists already, > > but I have to ask WHY is it correct behaviour to call into that code > > for an existing mapping. > > As I have originally looked at this, I'll answer the question: > > The generic DT code parses the whole tree, and generates platform > devices as it goes. As part of the platform device creation, it > populates the IRQ resources, which translates into calling into > irq_create_of_mapping(). You could argue that this behaviour is crazy, > and I wouldn't disagree. Mooo. > See http://www.spinics.net/lists/devicetree/msg53164.html for more gory > details. > > > And why would this check only apply if domain->ops->xlate is set? > > irq_create_mapping() does it unconditionally. > > My original code used the xlate callback to parse the opaque irq_data, > computing hwirq, and I suspect this is a leftover of it. The above code > seems to pull hwirq out of thin air, which is probably not the intended > behaviour. Joe? No. Here is the full patch from Joe: http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/296543.html hwirq gets either set from hwirq = irq_data->args[0] or from the xlate call. But my question still stands: Why would this check only apply if domain->ops->xlate is set? irq_create_mapping() does it unconditionally. Thanks, tglx
On 28/10/14 20:23, Thomas Gleixner wrote: > On Tue, 28 Oct 2014, Marc Zyngier wrote: >> On 28/10/14 19:37, Thomas Gleixner wrote: >>> So while we are at it: >>> >>>> + if (irq_domain_is_hierarchy(domain)) { >>>> + if (domain->ops->xlate) { >>>> + /* >>>> + * If we've already configured this interrupt, >>>> + * don't do it again, or hell will break loose. >>>> + */ >>>> + virq = irq_find_mapping(domain, hwirq); >>>> + if (virq) >>>> + return virq; >>> >>> I can understand that it is an issue if the mapping exists already, >>> but I have to ask WHY is it correct behaviour to call into that code >>> for an existing mapping. >> >> As I have originally looked at this, I'll answer the question: >> >> The generic DT code parses the whole tree, and generates platform >> devices as it goes. As part of the platform device creation, it >> populates the IRQ resources, which translates into calling into >> irq_create_of_mapping(). You could argue that this behaviour is crazy, >> and I wouldn't disagree. > > Mooo. Quite. >> See http://www.spinics.net/lists/devicetree/msg53164.html for more gory >> details. >> >>> And why would this check only apply if domain->ops->xlate is set? >>> irq_create_mapping() does it unconditionally. >> >> My original code used the xlate callback to parse the opaque irq_data, >> computing hwirq, and I suspect this is a leftover of it. The above code >> seems to pull hwirq out of thin air, which is probably not the intended >> behaviour. Joe? > > No. Here is the full patch from Joe: > > http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/296543.html > > hwirq gets either set from hwirq = irq_data->args[0] or from the xlate > call. Ah, that makes a lot more sense. > But my question still stands: > > Why would this check only apply if domain->ops->xlate is set? > irq_create_mapping() does it unconditionally. I don't think we should consider xlate at all. We already resolved hwirq (either directly or through a xlate call), and the check should always be performed (otherwise we're likely to fall into the same trap again). Looks like a bug to me. Thanks, M.
On Wed, 2014-10-29 at 09:27 +0000, Marc Zyngier wrote: > On 28/10/14 20:23, Thomas Gleixner wrote: > > On Tue, 28 Oct 2014, Marc Zyngier wrote: > >> On 28/10/14 19:37, Thomas Gleixner wrote: > >>> So while we are at it: > >>> > >>>> + if (irq_domain_is_hierarchy(domain)) { > >>>> + if (domain->ops->xlate) { > >>>> + /* > >>>> + * If we've already configured this interrupt, > >>>> + * don't do it again, or hell will break loose. > >>>> + */ > >>>> + virq = irq_find_mapping(domain, hwirq); > >>>> + if (virq) > >>>> + return virq; > >>> > >>> I can understand that it is an issue if the mapping exists already, > >>> but I have to ask WHY is it correct behaviour to call into that code > >>> for an existing mapping. > >> > >> As I have originally looked at this, I'll answer the question: > >> > >> The generic DT code parses the whole tree, and generates platform > >> devices as it goes. As part of the platform device creation, it > >> populates the IRQ resources, which translates into calling into > >> irq_create_of_mapping(). You could argue that this behaviour is crazy, > >> and I wouldn't disagree. > > > > Mooo. > > Quite. > > >> See http://www.spinics.net/lists/devicetree/msg53164.html for more gory > >> details. > >> > >>> And why would this check only apply if domain->ops->xlate is set? > >>> irq_create_mapping() does it unconditionally. > >> > >> My original code used the xlate callback to parse the opaque irq_data, > >> computing hwirq, and I suspect this is a leftover of it. The above code > >> seems to pull hwirq out of thin air, which is probably not the intended > >> behaviour. Joe? > > > > No. Here is the full patch from Joe: > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/296543.html > > > > hwirq gets either set from hwirq = irq_data->args[0] or from the xlate > > call. > > Ah, that makes a lot more sense. > > > But my question still stands: > > > > Why would this check only apply if domain->ops->xlate is set? > > irq_create_mapping() does it unconditionally. > > I don't think we should consider xlate at all. We already resolved hwirq > (either directly or through a xlate call), and the check should always > be performed (otherwise we're likely to fall into the same trap again). > Looks like a bug to me. I see it now. When irq_create_of_mapping() is called, we know there exists a mapping between irq_data and hwirq. If xlate exists, we get the mapping from xlate call, otherwise irq_data->args[0] is hwirq. This is true even when using hierarchy irqdomain. So yes, we should also check for existing mapping for empty domain->ops->xlate. I corrected this in my latest version. http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/298158.html Thanks for catching this. Joe.C
diff --git a/Documentation/IRQ-domain.txt b/Documentation/IRQ-domain.txt index 8a8b82c9ca53..39cfa72732ff 100644 --- a/Documentation/IRQ-domain.txt +++ b/Documentation/IRQ-domain.txt @@ -151,3 +151,74 @@ used and no descriptor gets allocated it is very important to make sure that the driver using the simple domain call irq_create_mapping() before any irq_find_mapping() since the latter will actually work for the static IRQ assignment case. + +==== Hierarchy IRQ domain ==== +On some architectures, there may be multiple interrupt controllers +involved in delivering an interrupt from the device to the target CPU. +Let's look at a typical interrupt delivering path on x86 platforms: + +Device --> IOAPIC -> Interrupt remapping Controller -> Local APIC -> CPU + +There are three interrupt controllers involved: +1) IOAPIC controller +2) Interrupt remapping controller +3) Local APIC controller + +To support such a hardware topology and make software architecture match +hardware architecture, an irq_domain data structure is built for each +interrupt controller and those irq_domains are organized into hierarchy. +When building irq_domain hierarchy, the irq_domain near to the device is +child and the irq_domain near to CPU is parent. So a hierarchy structure +as below will be built for the example above. + CPU Vector irq_domain (root irq_domain to manage CPU vectors) + ^ + | + Interrupt Remapping irq_domain (manage irq_remapping entries) + ^ + | + IOAPIC irq_domain (manage IOAPIC delivery entries/pins) + +There are four major interfaces to use hierarchy irq_domain: +1) irq_domain_alloc_irqs(): allocate IRQ descriptors and interrupt + controller related resources to deliver these interrupts. +2) irq_domain_free_irqs(): free IRQ descriptors and interrupt controller + related resources associated with these interrupts. +3) irq_domain_activate_irq(): activate interrupt controller hardware to + deliver the interrupt. +3) irq_domain_deactivate_irq(): deactivate interrupt controller hardware + to stop delivering the interrupt. + +Following changes are needed to support hierarchy irq_domain. +1) a new field 'parent' is added to struct irq_domain; it's used to + maintain irq_domain hierarchy information. +2) a new field 'parent_data' is added to struct irq_data; it's used to + build hierarchy irq_data to match hierarchy irq_domains. The irq_data + is used to store irq_domain pointer and hardware irq number. +3) new callbacks are added to struct irq_domain_ops to support hierarchy + irq_domain operations. + +With support of hierarchy irq_domain and hierarchy irq_data ready, an +irq_domain structure is built for each interrupt controller, and an +irq_data structure is allocated for each irq_domain associated with an +IRQ. Now we could go one step further to support stacked(hierarchy) +irq_chip. That is, an irq_chip is associated with each irq_data along +the hierarchy. A child irq_chip may implement a required action by +itself or by cooperating with its parent irq_chip. + +With stacked irq_chip, interrupt controller driver only needs to deal +with the hardware managed by itself and may ask for services from its +parent irq_chip when needed. So we could achieve a much cleaner +software architecture. + +For an interrupt controller driver to support hierarchy irq_domain, it +needs to: +1) Implement irq_domain_ops.alloc and irq_domain_ops.free +2) Optionally implement irq_domain_ops.activate and + irq_domain_ops.deactivate. +3) Optionally implement an irq_chip to manage the interrupt controller + hardware. +4) No need to implement irq_domain_ops.map and irq_domain_ops.unmap, + they are unused with hierarchy irq_domain. + +Hierarchy irq_domain may also be used to support other architectures, +such as ARM, ARM64 etc. diff --git a/include/linux/irq.h b/include/linux/irq.h index 03f48d936f66..13ba412ce3a0 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -133,6 +133,8 @@ struct irq_domain; * @chip: low level interrupt hardware access * @domain: Interrupt translation domain; responsible for mapping * between hwirq number and linux irq number. + * @parent_data: pointer to parent struct irq_data to support hierarchy + * irq_domain * @handler_data: per-IRQ data for the irq_chip methods * @chip_data: platform-specific per-chip private data for the chip * methods, to allow shared chip implementations @@ -151,6 +153,9 @@ struct irq_data { unsigned int state_use_accessors; struct irq_chip *chip; struct irq_domain *domain; +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + struct irq_data *parent_data; +#endif void *handler_data; void *chip_data; struct msi_desc *msi_desc; diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index b0f9d16e48f6..b20b34b1a8ea 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -38,6 +38,8 @@ struct device_node; struct irq_domain; struct of_device_id; +struct irq_chip; +struct irq_data; /* Number of irqs reserved for a legacy isa controller */ #define NUM_ISA_INTERRUPTS 16 @@ -64,6 +66,16 @@ struct irq_domain_ops { int (*xlate)(struct irq_domain *d, struct device_node *node, const u32 *intspec, unsigned int intsize, unsigned long *out_hwirq, unsigned int *out_type); + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + /* extended V2 interfaces to support hierarchy irq_domains */ + int (*alloc)(struct irq_domain *d, unsigned int virq, + unsigned int nr_irqs, void *arg); + void (*free)(struct irq_domain *d, unsigned int virq, + unsigned int nr_irqs); + int (*activate)(struct irq_domain *d, struct irq_data *irq_data); + int (*deactivate)(struct irq_domain *d, struct irq_data *irq_data); +#endif }; extern struct irq_domain_ops irq_generic_chip_ops; @@ -77,6 +89,7 @@ struct irq_domain_chip_generic; * @ops: pointer to irq_domain methods * @host_data: private data pointer for use by owner. Not touched by irq_domain * core code. + * @flags: host per irq_domain flags * * Optional elements * @of_node: Pointer to device tree nodes associated with the irq_domain. Used @@ -84,6 +97,7 @@ struct irq_domain_chip_generic; * @gc: Pointer to a list of generic chips. There is a helper function for * setting up one or more generic chips for interrupt controllers * drivers using the generic chip library which uses this pointer. + * @parent: Pointer to parent irq_domain to support hierarchy irq_domains * * Revmap data, used internally by irq_domain * @revmap_direct_max_irq: The largest hwirq that can be set for controllers that @@ -97,10 +111,14 @@ struct irq_domain { const char *name; const struct irq_domain_ops *ops; void *host_data; + unsigned int flags; /* Optional data */ struct device_node *of_node; struct irq_domain_chip_generic *gc; +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + struct irq_domain *parent; +#endif /* reverse map data. The linear map gets appended to the irq_domain */ irq_hw_number_t hwirq_max; @@ -110,6 +128,9 @@ struct irq_domain { unsigned int linear_revmap[]; }; +#define IRQ_DOMAIN_FLAG_HIERARCHY 0x1 +#define IRQ_DOMAIN_FLAG_ARCH1 0x10000 + #ifdef CONFIG_IRQ_DOMAIN struct irq_domain *__irq_domain_add(struct device_node *of_node, int size, irq_hw_number_t hwirq_max, int direct_max, @@ -220,8 +241,68 @@ int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr, const u32 *intspec, unsigned int intsize, irq_hw_number_t *out_hwirq, unsigned int *out_type); +/* V2 interfaces to support hierarchy IRQ domains. */ +extern struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, + unsigned int virq); +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY +extern int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, + unsigned int virq, + irq_hw_number_t hwirq, + struct irq_chip *chip, + void *chip_data); +extern void irq_domain_reset_irq_data(struct irq_data *irq_data); +extern int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, + unsigned int nr_irqs, int node, void *arg, + bool realloc); +extern void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs); +extern int irq_domain_activate_irq(struct irq_data *irq_data); +extern int irq_domain_deactivate_irq(struct irq_data *irq_data); + +static inline int irq_domain_alloc_irqs(struct irq_domain *domain, + unsigned int nr_irqs, int node, void *arg) +{ + return __irq_domain_alloc_irqs(domain, -1, nr_irqs, node, arg, false); +} + +static inline int irq_domain_alloc_irqs_parent(struct irq_domain *domain, + int irq_base, unsigned int nr_irqs, void *arg) +{ + if (domain->parent && domain->parent->ops->alloc) + return domain->parent->ops->alloc(domain->parent, irq_base, + nr_irqs, arg); + return -ENOSYS; +} + +static inline void irq_domain_free_irqs_parent(struct irq_domain *domain, + int irq_base, unsigned int nr_irqs) +{ + if (domain->parent && domain->parent->ops->free) + domain->parent->ops->free(domain->parent, irq_base, nr_irqs); +} + +static inline bool irq_domain_is_hierarchy(struct irq_domain *domain) +{ + return domain->flags & IRQ_DOMAIN_FLAG_HIERARCHY; +} +#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */ +static inline int irq_domain_activate_irq(struct irq_data *data) { return 0; } +static inline int irq_domain_deactivate_irq(struct irq_data *data) { return 0; } +static inline int irq_domain_alloc_irqs(struct irq_domain *domain, + unsigned int nr_irqs, int node, void *arg) +{ + return -1; +} + +static inline bool irq_domain_is_hierarchy(struct irq_domain *domain) +{ + return false; +} +#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ + #else /* CONFIG_IRQ_DOMAIN */ static inline void irq_dispose_mapping(unsigned int virq) { } +static inline int irq_domain_activate_irq(struct irq_data *data) { return 0; } +static inline int irq_domain_deactivate_irq(struct irq_data *data) { return 0; } #endif /* !CONFIG_IRQ_DOMAIN */ #endif /* _LINUX_IRQDOMAIN_H */ diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 225086b2652e..e9b580eccc01 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -55,6 +55,10 @@ config GENERIC_IRQ_CHIP config IRQ_DOMAIN bool +config IRQ_DOMAIN_HIERARCHY + bool + depends on IRQ_DOMAIN + config HANDLE_DOMAIN_IRQ bool diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index e5202f00cabc..72a93086216b 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -15,6 +15,7 @@ #include <linux/module.h> #include <linux/interrupt.h> #include <linux/kernel_stat.h> +#include <linux/irqdomain.h> #include <trace/events/irq.h> @@ -178,6 +179,7 @@ int irq_startup(struct irq_desc *desc, bool resend) irq_state_clr_disabled(desc); desc->depth = 0; + irq_domain_activate_irq(&desc->irq_data); if (desc->irq_data.chip->irq_startup) { ret = desc->irq_data.chip->irq_startup(&desc->irq_data); irq_state_clr_masked(desc); @@ -199,6 +201,7 @@ void irq_shutdown(struct irq_desc *desc) desc->irq_data.chip->irq_disable(&desc->irq_data); else desc->irq_data.chip->irq_mask(&desc->irq_data); + irq_domain_deactivate_irq(&desc->irq_data); irq_state_set_masked(desc); } diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 6534ff6ce02e..7cc9cbb0f240 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -23,6 +23,10 @@ static DEFINE_MUTEX(irq_domain_mutex); static DEFINE_MUTEX(revmap_trees_mutex); static struct irq_domain *irq_default_domain; +static int irq_domain_alloc_descs(int virq, unsigned int nr_irqs, + irq_hw_number_t hwirq, int node); +static void irq_domain_check_hierarchy(struct irq_domain *domain); + /** * __irq_domain_add() - Allocate a new irq_domain data structure * @of_node: optional device-tree node of the interrupt controller @@ -30,7 +34,7 @@ static struct irq_domain *irq_default_domain; * @hwirq_max: Maximum number of interrupts supported by controller * @direct_max: Maximum value of direct maps; Use ~0 for no limit; 0 for no * direct mapping - * @ops: map/unmap domain callbacks + * @ops: domain callbacks * @host_data: Controller private data pointer * * Allocates and initialize and irq_domain structure. @@ -56,6 +60,7 @@ struct irq_domain *__irq_domain_add(struct device_node *of_node, int size, domain->hwirq_max = hwirq_max; domain->revmap_size = size; domain->revmap_direct_max_irq = direct_max; + irq_domain_check_hierarchy(domain); mutex_lock(&irq_domain_mutex); list_add(&domain->link, &irq_domain_list); @@ -109,7 +114,7 @@ EXPORT_SYMBOL_GPL(irq_domain_remove); * @first_irq: first number of irq block assigned to the domain, * pass zero to assign irqs on-the-fly. If first_irq is non-zero, then * pre-map all of the irqs in the domain to virqs starting at first_irq. - * @ops: map/unmap domain callbacks + * @ops: domain callbacks * @host_data: Controller private data pointer * * Allocates an irq_domain, and optionally if first_irq is positive then also @@ -174,10 +179,8 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, domain = __irq_domain_add(of_node, first_hwirq + size, first_hwirq + size, 0, ops, host_data); - if (!domain) - return NULL; - - irq_domain_associate_many(domain, first_irq, first_hwirq, size); + if (domain) + irq_domain_associate_many(domain, first_irq, first_hwirq, size); return domain; } @@ -388,7 +391,6 @@ EXPORT_SYMBOL_GPL(irq_create_direct_mapping); unsigned int irq_create_mapping(struct irq_domain *domain, irq_hw_number_t hwirq) { - unsigned int hint; int virq; pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); @@ -410,12 +412,8 @@ unsigned int irq_create_mapping(struct irq_domain *domain, } /* Allocate a virtual interrupt number */ - hint = hwirq % nr_irqs; - if (hint == 0) - hint++; - virq = irq_alloc_desc_from(hint, of_node_to_nid(domain->of_node)); - if (virq <= 0) - virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node)); + virq = irq_domain_alloc_descs(-1, 1, hwirq, + of_node_to_nid(domain->of_node)); if (virq <= 0) { pr_debug("-> virq allocation failed\n"); return 0; @@ -471,7 +469,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) struct irq_domain *domain; irq_hw_number_t hwirq; unsigned int type = IRQ_TYPE_NONE; - unsigned int virq; + int virq; domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain; if (!domain) { @@ -480,6 +478,11 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) return 0; } + if (irq_domain_is_hierarchy(domain)) { + virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data); + return virq <= 0 ? 0 : virq; + } + /* If domain has no translation, then we assume interrupt line */ if (domain->ops->xlate == NULL) hwirq = irq_data->args[0]; @@ -540,8 +543,8 @@ unsigned int irq_find_mapping(struct irq_domain *domain, return 0; if (hwirq < domain->revmap_direct_max_irq) { - data = irq_get_irq_data(hwirq); - if (data && (data->domain == domain) && (data->hwirq == hwirq)) + data = irq_domain_get_irq_data(domain, hwirq); + if (data && data->hwirq == hwirq) return hwirq; } @@ -709,3 +712,341 @@ const struct irq_domain_ops irq_domain_simple_ops = { .xlate = irq_domain_xlate_onetwocell, }; EXPORT_SYMBOL_GPL(irq_domain_simple_ops); + +static int irq_domain_alloc_descs(int virq, unsigned int cnt, + irq_hw_number_t hwirq, int node) +{ + unsigned int hint; + + if (virq >= 0) { + virq = irq_alloc_descs(virq, virq, cnt, node); + } else { + hint = hwirq % nr_irqs; + if (hint == 0) + hint++; + virq = irq_alloc_descs_from(hint, cnt, node); + if (virq <= 0 && hint > 1) + virq = irq_alloc_descs_from(1, cnt, node); + } + + return virq; +} + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY +static void irq_domain_insert_irq(int virq) +{ + struct irq_data *data; + + for (data = irq_get_irq_data(virq); data; data = data->parent_data) { + struct irq_domain *domain = data->domain; + irq_hw_number_t hwirq = data->hwirq; + + if (hwirq < domain->revmap_size) { + domain->linear_revmap[hwirq] = virq; + } else { + mutex_lock(&revmap_trees_mutex); + radix_tree_insert(&domain->revmap_tree, hwirq, data); + mutex_unlock(&revmap_trees_mutex); + } + + /* If not already assigned, give the domain the chip's name */ + if (!domain->name && data->chip) + domain->name = data->chip->name; + } + + irq_clear_status_flags(virq, IRQ_NOREQUEST); +} + +static void irq_domain_remove_irq(int virq) +{ + struct irq_data *data; + + irq_set_status_flags(virq, IRQ_NOREQUEST); + irq_set_chip_and_handler(virq, NULL, NULL); + synchronize_irq(virq); + smp_mb(); + + for (data = irq_get_irq_data(virq); data; data = data->parent_data) { + struct irq_domain *domain = data->domain; + irq_hw_number_t hwirq = data->hwirq; + + if (hwirq < domain->revmap_size) { + domain->linear_revmap[hwirq] = 0; + } else { + mutex_lock(&revmap_trees_mutex); + radix_tree_delete(&domain->revmap_tree, hwirq); + mutex_unlock(&revmap_trees_mutex); + } + } +} + +static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain, + struct irq_data *child) +{ + struct irq_data *irq_data; + + irq_data = kzalloc_node(sizeof(*irq_data), GFP_KERNEL, child->node); + if (irq_data) { + child->parent_data = irq_data; + irq_data->irq = child->irq; + irq_data->node = child->node; + irq_data->domain = domain; + } + + return irq_data; +} + +static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs) +{ + int i; + struct irq_data *irq_data, *tmp; + + for (i = 0; i < nr_irqs; i++) { + irq_data = irq_get_irq_data(virq + i); + tmp = irq_data->parent_data; + irq_data->parent_data = NULL; + irq_data->domain = NULL; + + while (tmp) { + irq_data = tmp; + tmp = tmp->parent_data; + kfree(irq_data); + } + } +} + +static int irq_domain_alloc_irq_data(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + int i; + struct irq_data *irq_data; + struct irq_domain *parent; + + /* The outermost irq_data is embedded in struct irq_desc */ + for (i = 0; i < nr_irqs; i++) { + irq_data = irq_get_irq_data(virq + i); + irq_data->domain = domain; + + for (parent = domain->parent; parent; parent = parent->parent) { + irq_data = irq_domain_insert_irq_data(parent, irq_data); + if (!irq_data) { + irq_domain_free_irq_data(virq, i + 1); + return -ENOMEM; + } + } + } + + return 0; +} + +/** + * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain + * @domain: domain to match + * @virq: IRQ number to get irq_data + */ +struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, + unsigned int virq) +{ + struct irq_data *irq_data; + + for (irq_data = irq_get_irq_data(virq); irq_data; + irq_data = irq_data->parent_data) + if (irq_data->domain == domain) + return irq_data; + + return NULL; +} + +int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, unsigned int virq, + irq_hw_number_t hwirq, struct irq_chip *chip, + void *chip_data) +{ + struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq); + + if (!irq_data) + return -ENOENT; + + irq_data->hwirq = hwirq; + irq_data->chip = chip ? chip : &no_irq_chip; + irq_data->chip_data = chip_data; + + return 0; +} + +void irq_domain_reset_irq_data(struct irq_data *irq_data) +{ + irq_data->hwirq = 0; + irq_data->chip = &no_irq_chip; + irq_data->chip_data = NULL; +} + +/** + * __irq_domain_alloc_irqs - Allocate IRQs from domain + * @domain: domain to allocate from + * @irq_base: allocate specified IRQ nubmer if irq_base >= 0 + * @nr_irqs: number of IRQs to allocate + * @node: NUMA node id for memory allocation + * @arg: domain specific argument + * @realloc: IRQ descriptors have already been allocated if true + * + * Allocate IRQ numbers and initialized all data structures to support + * hiearchy IRQ domains. + * Parameter @realloc is mainly to support legacy IRQs. + * Returns error code or allocated IRQ number + * + * The whole process to setup an IRQ has been split into two steps. + * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ + * descriptor and required hardware resources. The second step, + * irq_domain_activate_irq(), is to program hardwares with preallocated + * resources. In this way, it's easier to rollback when failing to + * allocate resources. + */ +int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, + unsigned int nr_irqs, int node, void *arg, + bool realloc) +{ + int i, ret, virq; + + if (domain == NULL) { + domain = irq_default_domain; + if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n")) + return -EINVAL; + } + + if (!domain->ops->alloc) { + pr_debug("domain->ops->alloc() is NULL\n"); + return -ENOSYS; + } + + if (realloc && irq_base >= 0) { + virq = irq_base; + } else { + virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node); + if (virq < 0) { + pr_debug("cannot allocate IRQ(base %d, count %d)\n", + irq_base, nr_irqs); + return virq; + } + } + + if (irq_domain_alloc_irq_data(domain, virq, nr_irqs)) { + pr_debug("cannot allocate memory for IRQ%d\n", virq); + ret = -ENOMEM; + goto out_free_desc; + } + + mutex_lock(&irq_domain_mutex); + ret = domain->ops->alloc(domain, virq, nr_irqs, arg); + if (ret < 0) { + mutex_unlock(&irq_domain_mutex); + goto out_free_irq_data; + } + for (i = 0; i < nr_irqs; i++) + irq_domain_insert_irq(virq + i); + mutex_unlock(&irq_domain_mutex); + + return virq; + +out_free_irq_data: + irq_domain_free_irq_data(virq, nr_irqs); +out_free_desc: + irq_free_descs(virq, nr_irqs); + return ret; +} + +/** + * irq_domain_free_irqs - Free IRQ number and associated data structures + * @virq: base IRQ number + * @nr_irqs: number of IRQs to free + */ +void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs) +{ + int i; + struct irq_data *data = irq_get_irq_data(virq); + + if (WARN(!data || !data->domain || !data->domain->ops->free, + "NULL pointer, cannot free irq\n")) + return; + + mutex_lock(&irq_domain_mutex); + for (i = 0; i < nr_irqs; i++) + irq_domain_remove_irq(virq + i); + data->domain->ops->free(data->domain, virq, nr_irqs); + mutex_unlock(&irq_domain_mutex); + + irq_domain_free_irq_data(virq, nr_irqs); + irq_free_descs(virq, nr_irqs); +} + +/** + * irq_domain_activate_irq - Call domain_ops->activate recursively to activate + * interrupt + * @irq_data: outermost irq_data associated with interrupt + * + * This is the second step to call domain_ops->activate to program interrupt + * controllers, so the interrupt could actually get delivered. + */ +int irq_domain_activate_irq(struct irq_data *irq_data) +{ + int ret = 0; + + if (irq_data && irq_data->domain) { + struct irq_domain *domain = irq_data->domain; + + if (irq_data->parent_data) + ret = irq_domain_activate_irq(irq_data->parent_data); + if (ret == 0 && domain->ops->activate) + ret = domain->ops->activate(domain, irq_data); + } + + return ret; +} + +/** + * irq_domain_deactivate_irq - Call domain_ops->deactivate recursively to + * deactivate interrupt + * @irq_data: outermost irq_data associated with interrupt + * + * It calls domain_ops->deactivate to program interrupt controllers to disable + * interrupt delivery. + */ +int irq_domain_deactivate_irq(struct irq_data *irq_data) +{ + int ret = 0; + + if (irq_data && irq_data->domain) { + struct irq_domain *domain = irq_data->domain; + + if (domain->ops->deactivate) + ret = domain->ops->deactivate(domain, irq_data); + if (ret == 0 && irq_data->parent_data) + ret = irq_domain_deactivate_irq(irq_data->parent_data); + } + + return ret; +} + +static void irq_domain_check_hierarchy(struct irq_domain *domain) +{ + /* Hierarchy irq_domains must implement callback alloc() */ + if (domain->ops->alloc) + domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY; +} +#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */ +/** + * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain + * @domain: domain to match + * @virq: IRQ number to get irq_data + */ +struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain, + unsigned int virq) +{ + struct irq_data *irq_data = irq_get_irq_data(virq); + + return (irq_data && irq_data->domain == domain) ? irq_data : NULL; +} + +static void irq_domain_check_hierarchy(struct irq_domain *domain) +{ +} +#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
We plan to use hierarchy irqdomain to suppport CPU vector assignment, interrupt remapping controller, IO-APIC controller, MSI interrupt and hypertransport interrupt etc on x86 platforms. So extend irqdomain interfaces to support hierarchy irqdomain. There are already many clients of current irqdomain interfaces. To minimize the changes, we choose to introduce new version 2 interfaces to support hierarchy instead of extending existing irqdomain interfaces. According to Thomas's suggestion, the most important design decision is to build hierarchy struct irq_data to support hierarchy irqdomain, so hierarchy irqdomain related data could be saved in struct irq_data. With support of hierarchy irq_data, we could also support stacked irq_chips. This is most useful in case of set_affinity(). The new hierarchy irqdomain introduces following interfaces: 1) irq_domain_alloc_irqs()/irq_domain_free_irqs(): allocate/release IRQ and related resources. 2) __irq_domain_alloc_irqs(): a special version to support legacy IRQs. 3) irq_domain_activate_irq()/irq_domain_deactivate_irq(): program interrupt controllers to activate/deactivate interrupt. There are also several help functions to ease irqdomain implemenations: 1) irq_domain_get_irq_data(): get irq_data associated with a specific irqdomain. 2) irq_domain_set_hwirq_and_chip(): save irqdomain specific data into irq_data. 3) irq_domain_alloc_irqs_parent()/irq_domain_free_irqs_parent(): invoke parent irqdomain's alloc/free callbacks. We also changed irq_startup()/irq_shutdown() to invoke irq_domain_activate_irq()/irq_domain_deactivate_irq() to program interrupt controller when start/stop interrupts. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> --- Documentation/IRQ-domain.txt | 71 ++++++++ include/linux/irq.h | 5 + include/linux/irqdomain.h | 81 +++++++++ kernel/irq/Kconfig | 4 + kernel/irq/chip.c | 3 + kernel/irq/irqdomain.c | 373 ++++++++++++++++++++++++++++++++++++++++-- 6 files changed, 521 insertions(+), 16 deletions(-)