On Thu, Aug 11, 2016 at 12:06:32PM +0200, Tomasz Nowicki wrote:
[...]
> +/**
> + * iort_register_domain_token() - register domain token and related ITS ID
> + * to the list from where we can get it back later on.
> + * @trans_id: ITS ID.
> + * @fw_node: Domain token.
> + *
> + * Returns: 0 on success, -ENOMEM if no memory when allocating list element
> + */
> +int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node)
> +{
> + struct iort_its_msi_chip *its_msi_chip;
> +
> + its_msi_chip = kzalloc(sizeof(*its_msi_chip), GFP_KERNEL);
I spotted this while reworking my ARM SMMU series, this may sleep
and that's no good given that we call it within the acpi_probe_lock.
Same goes for irq_domain_alloc_fwnode() (that we call in
gic_v2_acpi_init()), we have got to fix this usage, I will see with
Marc what's the best way to do it.
Lorenzo
> + if (!its_msi_chip)
> + return -ENOMEM;
> +
> + its_msi_chip->fw_node = fw_node;
> + its_msi_chip->translation_id = trans_id;
> +
> + spin_lock(&iort_msi_chip_lock);
> + list_add(&its_msi_chip->list, &iort_msi_chip_list);
> + spin_unlock(&iort_msi_chip_lock);
> +
> + return 0;
> +}
> +
> +/**
> + * iort_deregister_domain_token() - Deregister domain token based on ITS ID
> + * @trans_id: ITS ID.
> + *
> + * Returns: none.
> + */
> +void iort_deregister_domain_token(int trans_id)
> +{
> + struct iort_its_msi_chip *its_msi_chip, *t;
> +
> + spin_lock(&iort_msi_chip_lock);
> + list_for_each_entry_safe(its_msi_chip, t, &iort_msi_chip_list, list) {
> + if (its_msi_chip->translation_id == trans_id) {
> + list_del(&its_msi_chip->list);
> + kfree(its_msi_chip);
> + break;
> + }
> + }
> + spin_unlock(&iort_msi_chip_lock);
> +}
> +
> +/**
> + * iort_find_domain_token() - Find domain token based on given ITS ID
> + * @trans_id: ITS ID.
> + *
> + * Returns: domain token when find on the list, NULL otherwise
> + */
> +struct fwnode_handle *iort_find_domain_token(int trans_id)
> +{
> + struct fwnode_handle *fw_node = NULL;
> + struct iort_its_msi_chip *its_msi_chip;
> +
> + spin_lock(&iort_msi_chip_lock);
> + list_for_each_entry(its_msi_chip, &iort_msi_chip_list, list) {
> + if (its_msi_chip->translation_id == trans_id) {
> + fw_node = its_msi_chip->fw_node;
> + break;
> + }
> + }
> + spin_unlock(&iort_msi_chip_lock);
> +
> + return fw_node;
> +}
> +
> static struct acpi_iort_node *
> iort_scan_node(enum acpi_iort_node_type type,
> iort_find_node_callback callback, void *context)
> @@ -206,6 +285,96 @@ iort_find_dev_node(struct device *dev)
> iort_match_node_callback, &pbus->dev);
> }
>
> +/**
> + * iort_msi_map_rid() - Map a MSI requester ID for a device
> + * @dev: The device for which the mapping is to be done.
> + * @req_id: The device requester ID.
> + *
> + * Returns: mapped MSI RID on success, input requester ID otherwise
> + */
> +u32 iort_msi_map_rid(struct device *dev, u32 req_id)
> +{
> + struct acpi_iort_node *node;
> + u32 dev_id;
> +
> + if (!iort_table)
> + return req_id;
> +
> + node = iort_find_dev_node(dev);
> + if (!node) {
> + dev_err(dev, "can't find related IORT node\n");
> + return req_id;
> + }
> +
> + iort_node_map_rid(node, req_id, &dev_id, ACPI_IORT_NODE_ITS_GROUP);
> + return dev_id;
> +}
> +
> +/**
> + * iort_dev_find_its_id() - Find the ITS identifier for a device
> + * @dev: The device.
> + * @idx: Index of the ITS identifier list.
> + * @its_id: ITS identifier.
> + *
> + * Returns: 0 on success, appropriate error value otherwise
> + */
> +static int
> +iort_dev_find_its_id(struct device *dev, u32 req_id, unsigned int idx,
> + int *its_id)
> +{
> + struct acpi_iort_its_group *its;
> + struct acpi_iort_node *node;
> +
> + node = iort_find_dev_node(dev);
> + if (!node) {
> + dev_err(dev, "can't find related IORT node\n");
> + return -ENXIO;
> + }
> +
> + node = iort_node_map_rid(node, req_id, NULL, ACPI_IORT_NODE_ITS_GROUP);
> + if (!node) {
> + dev_err(dev, "can't find related ITS node\n");
> + return -ENXIO;
> + }
> +
> + /* Move to ITS specific data */
> + its = (struct acpi_iort_its_group *)node->node_data;
> + if (idx > its->its_count) {
> + dev_err(dev, "requested ITS ID index [%d] is greater than
> available [%d]\n",
> + idx, its->its_count);
> + return -ENXIO;
> + }
> +
> + *its_id = its->identifiers[idx];
> + return 0;
> +}
> +
> +/**
> + * iort_get_device_domain() - Find MSI domain related to a device
> + * @dev: The device.
> + * @req_id: Requester ID for the device.
> + *
> + * Returns: the MSI domain for this device, NULL otherwise
> + */
> +struct irq_domain *
> +iort_get_device_domain(struct device *dev, u32 req_id)
> +{
> + static struct fwnode_handle *handle;
> + int its_id;
> +
> + if (!iort_table)
> + return NULL;
> +
> + if (iort_dev_find_its_id(dev, req_id, 0, &its_id))
> + return NULL;
> +
> + handle = iort_find_domain_token(its_id);
> + if (!handle)
> + return NULL;
> +
> + return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
> +}
> +
> void __init iort_table_detect(void)
> {
> acpi_status status;
> diff --git a/include/linux/iort.h b/include/linux/iort.h
> index cde6809..d7daba1 100644
> --- a/include/linux/iort.h
> +++ b/include/linux/iort.h
> @@ -20,11 +20,22 @@
> #define __IORT_H__
>
> #include <linux/acpi.h>
> +#include <linux/fwnode.h>
> +#include <linux/irqdomain.h>
>
> +int iort_register_domain_token(int trans_id, struct fwnode_handle *fw_node);
> +void iort_deregister_domain_token(int trans_id);
> +struct fwnode_handle *iort_find_domain_token(int trans_id);
> #ifdef CONFIG_IORT_TABLE
> 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);
> #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; }
> #endif
>
> #endif /* __IORT_H__ */
> --
> 1.9.1
>
