Hi Shameer, On 11/19/20 1:11 PM, Shameer Kolothum wrote: > Add support for parsing RMR node information from ACPI. > Find associated stream ids and smmu node info from the > RMR node and populate a linked list with RMR memory > descriptors. > > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx> > --- > drivers/acpi/arm64/iort.c | 122 +++++++++++++++++++++++++++++++++++++- > 1 file changed, 121 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index 9929ff50c0c0..a9705aa35028 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -40,6 +40,25 @@ struct iort_fwnode { > static LIST_HEAD(iort_fwnode_list); > static DEFINE_SPINLOCK(iort_fwnode_lock); > > +struct iort_rmr_id { > + u32 sid; > + struct acpi_iort_node *smmu; > +}; > + > +/* > + * One entry for IORT RMR. > + */ > +struct iort_rmr_entry { > + struct list_head list; > + > + unsigned int rmr_ids_num; > + struct iort_rmr_id *rmr_ids; > + > + struct acpi_iort_rmr_desc *rmr_desc; > +}; > + > +static LIST_HEAD(iort_rmr_list); /* list of RMR regions from ACPI */ > + > /** > * iort_set_fwnode() - Create iort_fwnode and use it to register > * iommu data in the iort_fwnode_list > @@ -393,7 +412,8 @@ static struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node, > if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT || > node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX || > node->type == ACPI_IORT_NODE_SMMU_V3 || > - node->type == ACPI_IORT_NODE_PMCG) { > + node->type == ACPI_IORT_NODE_PMCG || > + node->type == ACPI_IORT_NODE_RMR) { > *id_out = map->output_base; > return parent; > } > @@ -1647,6 +1667,103 @@ static void __init iort_enable_acs(struct acpi_iort_node *iort_node) > #else > static inline void iort_enable_acs(struct acpi_iort_node *iort_node) { } > #endif > +static int iort_rmr_desc_valid(struct acpi_iort_rmr_desc *desc) > +{ > + struct iort_rmr_entry *e; > + u64 end, start = desc->base_address, length = desc->length; > + > + if (!IS_ALIGNED(start, SZ_64K) || !IS_ALIGNED(length, SZ_64K)) > + return -EINVAL; > + > + end = start + length - 1; > + > + /* Check for address overlap */ I don't get this check. What is the problem if you attach the same range to different stream ids. Shouldn't you check there is no overlap for the same sid? > + list_for_each_entry(e, &iort_rmr_list, list) { > + u64 e_start = e->rmr_desc->base_address; > + u64 e_end = e_start + e->rmr_desc->length - 1; > + > + if (start <= e_end && end >= e_start) > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int __init iort_parse_rmr(struct acpi_iort_node *iort_node) > +{ > + struct iort_rmr_id *rmr_ids, *ids; > + struct iort_rmr_entry *e; > + struct acpi_iort_rmr *rmr; > + struct acpi_iort_rmr_desc *rmr_desc; > + u32 map_count = iort_node->mapping_count; > + int i, ret = 0, desc_count = 0; > + > + if (iort_node->type != ACPI_IORT_NODE_RMR) > + return 0; > + > + if (!iort_node->mapping_offset || !map_count) { > + pr_err(FW_BUG "Invalid ID mapping, skipping RMR node %p\n", > + iort_node); > + return -EINVAL; > + } > + > + rmr_ids = kmalloc(sizeof(*rmr_ids) * map_count, GFP_KERNEL); > + if (!rmr_ids) > + return -ENOMEM; > + > + /* Retrieve associated smmu and stream id */ > + ids = rmr_ids; nit: do you need both rmr_ids and ids? > + for (i = 0; i < map_count; i++, ids++) { > + ids->smmu = iort_node_get_id(iort_node, &ids->sid, i); > + if (!ids->smmu) { > + pr_err(FW_BUG "Invalid SMMU reference, skipping RMR node %p\n", > + iort_node); > + ret = -EINVAL; > + goto out; > + } > + } > + > + /* Retrieve RMR data */ > + rmr = (struct acpi_iort_rmr *)iort_node->node_data; > + if (!rmr->rmr_offset || !rmr->rmr_count) { > + pr_err(FW_BUG "Invalid RMR descriptor array, skipping RMR node %p\n", > + iort_node); > + ret = -EINVAL; > + goto out; > + } > + > + rmr_desc = ACPI_ADD_PTR(struct acpi_iort_rmr_desc, iort_node, > + rmr->rmr_offset); > + > + for (i = 0; i < rmr->rmr_count; i++, rmr_desc++) { > + ret = iort_rmr_desc_valid(rmr_desc); > + if (ret) { > + pr_err(FW_BUG "Invalid RMR descriptor[%d] for node %p, skipping...\n", > + i, iort_node); > + goto out; so I understand you skip the whole node and not just that rmr desc, otherwise you would continue. so in that case don't you need to free both rmr_ids and already allocated 'e'? > + } > + > + e = kmalloc(sizeof(*e), GFP_KERNEL); > + if (!e) { > + ret = -ENOMEM; > + goto out; > + } > + > + e->rmr_ids_num = map_count; > + e->rmr_ids = rmr_ids; > + e->rmr_desc = rmr_desc; > + > + list_add_tail(&e->list, &iort_rmr_list); > + desc_count++; > + } > + > + return 0; > + > +out: > + if (!desc_count) don't you want to test ret instead? see comment above. + free allocated ''e' > + kfree(rmr_ids); > + return ret; > +} > > static void __init iort_init_platform_devices(void) > { > @@ -1676,6 +1793,9 @@ static void __init iort_init_platform_devices(void) > > iort_enable_acs(iort_node); > > + if (iort_table->revision == 1) > + iort_parse_rmr(iort_node); > + > ops = iort_get_dev_cfg(iort_node); > if (ops) { > fwnode = acpi_alloc_fwnode_static(); > Thanks Eric