diff options
author | Marc Zyngier <maz@kernel.org> | 2020-10-10 12:16:24 +0100 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2020-10-10 12:16:24 +0100 |
commit | 408f110ef6974b336cc0958bf123f5234f583869 (patch) | |
tree | 4ee91bd69b6a2f0b3bfe0a752402faf7c93ed760 /kernel/irq | |
parent | 04e8c5b2fa9a2ad66496c810562454fc324446a8 (diff) | |
parent | c351ab7bf2a565951172cadbdebe686137c3fd43 (diff) | |
download | linux-stable-408f110ef6974b336cc0958bf123f5234f583869.tar.gz linux-stable-408f110ef6974b336cc0958bf123f5234f583869.tar.bz2 linux-stable-408f110ef6974b336cc0958bf123f5234f583869.zip |
Merge branch 'irq/tegra-pmc' into irq/irqchip-next
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'kernel/irq')
-rw-r--r-- | kernel/irq/irqdomain.c | 99 |
1 files changed, 95 insertions, 4 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 76cd7ebd1178..cf8b374b892d 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -1136,6 +1136,17 @@ static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain, return irq_data; } +static void __irq_domain_free_hierarchy(struct irq_data *irq_data) +{ + struct irq_data *tmp; + + while (irq_data) { + tmp = irq_data; + irq_data = irq_data->parent_data; + kfree(tmp); + } +} + static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs) { struct irq_data *irq_data, *tmp; @@ -1147,12 +1158,83 @@ static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs) irq_data->parent_data = NULL; irq_data->domain = NULL; - while (tmp) { - irq_data = tmp; - tmp = tmp->parent_data; - kfree(irq_data); + __irq_domain_free_hierarchy(tmp); + } +} + +/** + * irq_domain_disconnect_hierarchy - Mark the first unused level of a hierarchy + * @domain: IRQ domain from which the hierarchy is to be disconnected + * @virq: IRQ number where the hierarchy is to be trimmed + * + * Marks the @virq level belonging to @domain as disconnected. + * Returns -EINVAL if @virq doesn't have a valid irq_data pointing + * to @domain. + * + * Its only use is to be able to trim levels of hierarchy that do not + * have any real meaning for this interrupt, and that the driver marks + * as such from its .alloc() callback. + */ +int irq_domain_disconnect_hierarchy(struct irq_domain *domain, + unsigned int virq) +{ + struct irq_data *irqd; + + irqd = irq_domain_get_irq_data(domain, virq); + if (!irqd) + return -EINVAL; + + irqd->chip = ERR_PTR(-ENOTCONN); + return 0; +} + +static int irq_domain_trim_hierarchy(unsigned int virq) +{ + struct irq_data *tail, *irqd, *irq_data; + + irq_data = irq_get_irq_data(virq); + tail = NULL; + + /* The first entry must have a valid irqchip */ + if (!irq_data->chip || IS_ERR(irq_data->chip)) + return -EINVAL; + + /* + * Validate that the irq_data chain is sane in the presence of + * a hierarchy trimming marker. + */ + for (irqd = irq_data->parent_data; irqd; irq_data = irqd, irqd = irqd->parent_data) { + /* Can't have a valid irqchip after a trim marker */ + if (irqd->chip && tail) + return -EINVAL; + + /* Can't have an empty irqchip before a trim marker */ + if (!irqd->chip && !tail) + return -EINVAL; + + if (IS_ERR(irqd->chip)) { + /* Only -ENOTCONN is a valid trim marker */ + if (PTR_ERR(irqd->chip) != -ENOTCONN) + return -EINVAL; + + tail = irq_data; } } + + /* No trim marker, nothing to do */ + if (!tail) + return 0; + + pr_info("IRQ%d: trimming hierarchy from %s\n", + virq, tail->parent_data->domain->name); + + /* Sever the inner part of the hierarchy... */ + irqd = tail; + tail = tail->parent_data; + irqd->parent_data = NULL; + __irq_domain_free_hierarchy(tail); + + return 0; } static int irq_domain_alloc_irq_data(struct irq_domain *domain, @@ -1362,6 +1444,15 @@ int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base, mutex_unlock(&irq_domain_mutex); goto out_free_irq_data; } + + for (i = 0; i < nr_irqs; i++) { + ret = irq_domain_trim_hierarchy(virq + i); + if (ret) { + 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); |