From mboxrd@z Thu Jan 1 00:00:00 1970 From: lv.zheng@intel.com (Zheng, Lv) Date: Tue, 16 Aug 2016 02:15:44 +0000 Subject: [PATCH V8 2/8] ACPI: Add new IORT functions to support MSI domain handling In-Reply-To: <20160812164234.GB17734@red-moon> References: <1470909998-16710-1-git-send-email-tn@semihalf.com> <1470909998-16710-3-git-send-email-tn@semihalf.com> <20160812164234.GB17734@red-moon> Message-ID: <1AE640813FDE7649BE1B193DEA596E883BC0E3F2@SHSMSX101.ccr.corp.intel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, > From: linux-acpi-owner at vger.kernel.org [mailto:linux-acpi-owner at vger.kernel.org] On Behalf Of Lorenzo > Pieralisi > Subject: Re: [PATCH V8 2/8] ACPI: Add new IORT functions to support MSI domain handling > > 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. If we can ensure that all table device probe entries are created during link stage or early stage. I think you can safely unlock probe lock before invoking acpi_table_parse() in __acpi_probe_device_table(). Thanks Lv > > 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 > > +#include > > +#include > > > > +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 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html