[Patch Part2 v3 01/24] irqdomain: Introduce new interfaces to support hierarchy irqdomains

Yingjoe Chen
2014-10-28T09:48:31Z

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 */