On 2014/11/12 21:43, Thomas Gleixner wrote:

> From: Jiang Liu <[email protected]>
> 
> Implement the basic functions for MSI interrupt support with
> hierarchical interrupt domains.
> 
> [ tglx: Extracted and combined from several patches ]
> 
> Signed-off-by: Jiang Liu <[email protected]>
> Cc: Bjorn Helgaas <[email protected]>
> Cc: Grant Likely <[email protected]>
> Cc: Marc Zyngier <[email protected]>
> Cc: Yingjoe Chen <[email protected]>
> Cc: Yijing Wang <[email protected]>
> Signed-off-by: Thomas Gleixner <[email protected]>
> ---
>  include/linux/msi.h |   35 +++++++++++++++
>  kernel/irq/Kconfig  |   10 ++++
>  kernel/irq/Makefile |    1 
>  kernel/irq/msi.c    |  119 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 165 insertions(+)
> 
> Index: tip/include/linux/msi.h
> ===================================================================
> --- tip.orig/include/linux/msi.h
> +++ tip/include/linux/msi.h
> @@ -77,4 +77,39 @@ struct msi_chip {
>       void (*teardown_irq)(struct msi_chip *chip, unsigned int irq);
>  };
>  
> +#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
> +struct irq_domain;
> +struct irq_chip;
> +struct device_node;
> +struct msi_domain_info;
> +
> +struct msi_domain_ops {
> +     void            (*calc_hwirq)(struct msi_domain_info *info, void *arg,
> +                                   struct msi_desc *desc);
> +     irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, void *arg);
> +     int             (*msi_init)(struct irq_domain *domain,
> +                                 struct msi_domain_info *info,
> +                                 unsigned int virq, irq_hw_number_t hwirq,
> +                                 void *arg);
> +     void            (*msi_free)(struct irq_domain *domain,
> +                                 struct msi_domain_info *info,
> +                                 unsigned int virq);
> +};
> +
> +struct msi_domain_info {
> +     struct msi_domain_ops   *ops;
> +     struct irq_chip         *chip;
> +     void                    *data;
> +};
> +
> +int msi_domain_set_affinity(struct irq_data *data, const struct cpumask 
> *mask,
> +                         bool force);
> +
> +struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
> +                                      struct msi_domain_info *info,
> +                                      struct irq_domain *parent);
> +struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);
> +
> +#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
> +
>  #endif /* LINUX_MSI_H */
> Index: tip/kernel/irq/Kconfig
> ===================================================================
> --- tip.orig/kernel/irq/Kconfig
> +++ tip/kernel/irq/Kconfig
> @@ -60,6 +60,16 @@ config IRQ_DOMAIN_HIERARCHY
>       bool
>       select IRQ_DOMAIN
>  
> +# Generic MSI interrupt support
> +config GENERIC_MSI_IRQ
> +     bool
> +
> +# Generic MSI hierarchical interrupt domain support
> +config GENERIC_MSI_IRQ_DOMAIN
> +     bool
> +     select IRQ_DOMAIN_HIERARCHY
> +     select GENERIC_MSI_IRQ
> +
>  config HANDLE_DOMAIN_IRQ
>       bool
>  
> Index: tip/kernel/irq/Makefile
> ===================================================================
> --- tip.orig/kernel/irq/Makefile
> +++ tip/kernel/irq/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o
>  obj-$(CONFIG_PROC_FS) += proc.o
>  obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
>  obj-$(CONFIG_PM_SLEEP) += pm.o
> +obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o
> Index: tip/kernel/irq/msi.c
> ===================================================================
> --- /dev/null
> +++ tip/kernel/irq/msi.c
> @@ -0,0 +1,119 @@
> +/*
> + * linux/kernel/irq/msi.c
> + *
> + * Copyright (C) 2014 Intel Corp.
> + * Author: Jiang Liu <[email protected]>
> + *
> + * This file is licensed under GPLv2.
> + *
> + * This file contains common code to support Message Signalled Interrupt for
> + * PCI compatible and non PCI compatible devices.
> + */
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/msi.h>
> +
> +#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
> +int msi_domain_set_affinity(struct irq_data *irq_data,
> +                         const struct cpumask *mask, bool force)
> +{
> +     struct irq_data *parent = irq_data->parent_data;
> +     struct msi_msg msg;
> +     int ret;
> +
> +     ret = parent->chip->irq_set_affinity(parent, mask, force);
> +     if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
> +             BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
> +             irq_chip_write_msi_msg(irq_data, &msg);
> +     }
> +
> +     return ret;
> +}
> +
> +static void msi_domain_activate(struct irq_domain *domain,
> +                             struct irq_data *irq_data)
> +{
> +     struct msi_msg msg;
> +
> +     BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg));
> +     irq_chip_write_msi_msg(irq_data, &msg);
> +}
> +
> +static void msi_domain_deactivate(struct irq_domain *domain,
> +                               struct irq_data *irq_data)
> +{
> +     struct msi_msg msg;
> +
> +     memset(&msg, 0, sizeof(msg));
> +     irq_chip_write_msi_msg(irq_data, &msg);
> +}
> +
> +static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
> +                         unsigned int nr_irqs, void *arg)
> +{
> +     struct msi_domain_info *info = domain->host_data;
> +     struct msi_domain_ops *ops = info->ops;
> +     irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
> +     int i, ret;
> +
> +     if (irq_find_mapping(domain, hwirq) > 0)
> +             return -EEXIST;

I think we need to check range here.
I fixed this by applying a patch showed in the bottom.

> +
> +     ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
> +     if (ret < 0)
> +             return ret;
> +
> +     for (i = 0; i < nr_irqs; i++) {
> +             ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
> +             if (ret < 0) {
> +                     if (ops->msi_free) {
> +                             for (i--; i > 0; i--)

while (i--) ?

Regards,
        Abel

> +                                     ops->msi_free(domain, info, virq + i);
> +                     }
> +                     irq_domain_free_irqs_top(domain, virq, nr_irqs);
> +                     return ret;
> +             }
> +     }
> +
> +     return 0;
> +}
> +
> +static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
> +                         unsigned int nr_irqs)
> +{
> +     struct msi_domain_info *info = domain->host_data;
> +     int i;
> +
> +     if (info->ops->msi_free) {
> +             for (i = 0; i < nr_irqs; i++)
> +                     info->ops->msi_free(domain, info, virq + i);
> +     }
> +     irq_domain_free_irqs_top(domain, virq, nr_irqs);
> +}
> +
> +static struct irq_domain_ops msi_domain_ops = {
> +     .alloc          = msi_domain_alloc,
> +     .free           = msi_domain_free,
> +     .activate       = msi_domain_activate,
> +     .deactivate     = msi_domain_deactivate,
> +};
> +
> +struct irq_domain *msi_create_irq_domain(struct device_node *of_node,
> +                                      struct msi_domain_info *info,
> +                                      struct irq_domain *parent)
> +{
> +     struct irq_domain *domain;
> +
> +     domain = irq_domain_add_tree(of_node, &msi_domain_ops, info);
> +     if (domain)
> +             domain->parent = parent;
> +
> +     return domain;
> +}
> +
> +struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
> +{
> +     return (struct msi_domain_info *)domain->host_data;
> +}
> +
> +#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */
> 
> 

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index cc18182..6d1be00 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -568,6 +568,34 @@ unsigned int irq_find_mapping(struct irq_domain *domain,
 }
 EXPORT_SYMBOL_GPL(irq_find_mapping);

+/**
+ * irq_find_mapping_many() - Find a range of linux irqs from a range of hwirqs.
+ * @domain:    domain owning these hardware interrupts
+ * @hwirq:     start hardware irq number in @domain space
+ * @count:     number of interrupts to find
+ *
+ * Returns the first linux irq number on success, or 0 when not found, or 
error.
+ */
+int irq_find_mapping_many(struct irq_domain *domain, irq_hw_number_t hwirq,
+                         int count)
+{
+       unsigned int from;
+       int i;
+
+       for (i = from = 0; i < count; i++) {
+               if (!from) {
+                       from = irq_find_mapping(domain, hwirq + i);
+                       if (from && i)
+                               return -1;
+               } else if ((from + i) != irq_find_mapping(domain, hwirq + i)) {
+                       return -1;
+               }
+       }
+
+       return from;
+}
+EXPORT_SYMBOL_GPL(irq_find_mapping_many);
+
 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 static int virq_debug_show(struct seq_file *m, void *private)
 {



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to