From 515085ef7ee74694bc9b02bc45196452defad59a Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Thu, 6 Nov 2014 22:20:17 +0800 Subject: [PATCH] genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip Add callback irq_compose_msi_msg to struct irq_chip, which will be used to support stacked irqchip. Signed-off-by: Jiang Liu Cc: Bjorn Helgaas Cc: Grant Likely Cc: Marc Zyngier Cc: Yingjoe Chen Cc: Yijing Wang Signed-off-by: Thomas Gleixner --- include/linux/irq.h | 5 +++++ kernel/irq/chip.c | 26 ++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/include/linux/irq.h b/include/linux/irq.h index fad4bf6f15f6..d58e58935465 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -29,6 +29,7 @@ struct seq_file; struct module; struct irq_desc; struct irq_data; +struct msi_msg; typedef void (*irq_flow_handler_t)(unsigned int irq, struct irq_desc *desc); typedef void (*irq_preflow_handler_t)(struct irq_data *data); @@ -320,6 +321,7 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) * any other callback related to this irq * @irq_release_resources: optional to release resources acquired with * irq_request_resources + * @irq_compose_msi_msg: optional to compose message content for MSI * @flags: chip specific flags */ struct irq_chip { @@ -356,6 +358,8 @@ struct irq_chip { int (*irq_request_resources)(struct irq_data *data); void (*irq_release_resources)(struct irq_data *data); + void (*irq_compose_msi_msg)(struct irq_data *data, struct msi_msg *msg); + unsigned long flags; }; @@ -443,6 +447,7 @@ extern void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc); extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc); extern void handle_nested_irq(unsigned int irq); +extern int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg); #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY extern void irq_chip_ack_parent(struct irq_data *data); extern int irq_chip_retrigger_hierarchy(struct irq_data *data); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 47f4c6469a43..63c16d165e78 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -926,3 +926,29 @@ int irq_chip_retrigger_hierarchy(struct irq_data *data) return -ENOSYS; } #endif + +/** + * irq_chip_compose_msi_msg - Componse msi message for a irq chip + * @data: Pointer to interrupt specific data + * @msg: Pointer to the MSI message + * + * For hierarchical domains we find the first chip in the hierarchy + * which implements the irq_compose_msi_msg callback. For non + * hierarchical we use the top level chip. + */ +int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct irq_data *pos = NULL; + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + for (; data; data = data->parent_data) +#endif + if (data->chip && data->chip->irq_compose_msi_msg) + pos = data; + if (!pos) + return -ENOSYS; + + pos->chip->irq_compose_msi_msg(pos, msg); + + return 0; +} -- 2.30.2