Re: [PATCH v4 04/15] drivers: acpi: iort: add support for IOMMU fwnode registration

[Hanjun Guo <hanjun.guo@linaro.org>]

On 2016/8/15 23:23, Lorenzo Pieralisi wrote:
> The ACPI IORT table provide entries for IOMMU (aka SMMU in ARM world)
> components that allow creating the kernel data structures required to
> probe and initialize the IOMMU devices.
>
> This patch provides support in the IORT kernel code to register IOMMU
> components and their respective fwnode.
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Hanjun Guo <hanjun.guo@linaro.org>
> Cc: Tomasz Nowicki <tn@semihalf.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> ---
>  drivers/acpi/arm64/iort.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/iort.h      |  8 ++++++
>  2 files changed, 73 insertions(+)
>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index cad7d1d..01a5258 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -20,7 +20,9 @@
>
>  #include <linux/iort.h>
>  #include <linux/kernel.h>
> +#include <linux/list.h>
>  #include <linux/pci.h>
> +#include <linux/slab.h>
>
>  struct iort_its_msi_chip {
>  	struct list_head	list;
> @@ -28,6 +30,69 @@ struct iort_its_msi_chip {
>  	u32			translation_id;
>  };
>
> +struct iort_fwnode {
> +	struct list_head list;
> +	struct acpi_iort_node *iort_node;
> +	struct fwnode_handle *fwnode;
> +};
> +static LIST_HEAD(iort_fwnode_list);
> +static DEFINE_SPINLOCK(iort_fwnode_lock);
> +
> +/**
> + * iort_set_fwnode() - Create iort_fwnode and use it to register
> + *		       iommu data in the iort_fwnode_list
> + *
> + * @node: IORT table node associated with the IOMMU
> + * @fwnode: fwnode associated with the IORT node
> + *
> + * Returns: 0 on success
> + *          <0 on failure
> + */
> +int iort_set_fwnode(struct acpi_iort_node *iort_node,
> +		    struct fwnode_handle *fwnode)
> +{
> +	struct iort_fwnode *np;
> +
> +	np = kzalloc(sizeof(struct iort_fwnode), GFP_ATOMIC);
> +
> +	if (WARN_ON(!np))
> +		return -ENOMEM;
> +
> +	INIT_LIST_HEAD(&np->list);
> +	np->iort_node = iort_node;
> +	np->fwnode = fwnode;
> +
> +	spin_lock(&iort_fwnode_lock);
> +	list_add_tail(&np->list, &iort_fwnode_list);
> +	spin_unlock(&iort_fwnode_lock);
> +
> +	return 0;
> +}
> +
> +/**
> + * iort_get_fwnode() - Retrieve fwnode associated with an IORT node
> + *
> + * @node: IORT table node to be looked-up
> + *
> + * Returns: fwnode_handle pointer on success, NULL on failure
> +*/
> +struct fwnode_handle *iort_get_fwnode(struct acpi_iort_node *node)
> +{
> +	struct iort_fwnode *curr;
> +	struct fwnode_handle *fwnode = NULL;
> +
> +	spin_lock(&iort_fwnode_lock);
> +	list_for_each_entry(curr, &iort_fwnode_list, list) {
> +		if (curr->iort_node == node) {
> +			fwnode = curr->fwnode;
> +			break;
> +		}
> +	}
> +	spin_unlock(&iort_fwnode_lock);
> +
> +	return fwnode;
> +}
> +
>  typedef acpi_status (*iort_find_node_callback)
>  	(struct acpi_iort_node *node, void *context);
>
> diff --git a/include/linux/iort.h b/include/linux/iort.h
> index 9bb30c5..666a3de 100644
> --- a/include/linux/iort.h
> +++ b/include/linux/iort.h
> @@ -30,12 +30,20 @@ struct fwnode_handle *iort_find_domain_token(int trans_id);
>  void iort_table_detect(void);
>  u32 iort_msi_map_rid(struct device *dev, u32 req_id);
>  struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id);
> +int iort_set_fwnode(struct acpi_iort_node *iort_node,
> +		    struct fwnode_handle *fwnode);
> +struct fwnode_handle *iort_get_fwnode(struct acpi_iort_node *node);
>  #else
>  static inline void iort_table_detect(void) { }
>  static inline u32 iort_msi_map_rid(struct device *dev, u32 req_id)
>  { return req_id; }
>  static inline struct irq_domain *
>  iort_get_device_domain(struct device *dev, u32 req_id) { return NULL; }
> +static inline int iort_set_fwnode(struct acpi_iort_node *iort_node,
> +				  struct fwnode_handle *fwnode)
> +{ return -ENODEV; }
> +static inline struct fwnode_handle *
> +iort_get_fwnode(struct acpi_iort_node *node) { return NULL; }
>  #endif
>
>  #define IORT_ACPI_DECLARE(name, table_id, fn)		\

Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>

Thanks
Hanjun