From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/iommu/of_iommu.c | 186 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 drivers/iommu/of_iommu.c (limited to 'drivers/iommu/of_iommu.c') diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c new file mode 100644 index 000000000..43429ab62 --- /dev/null +++ b/drivers/iommu/of_iommu.c @@ -0,0 +1,186 @@ +/* + * OF helpers for IOMMU + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include +#include +#include +#include +#include +#include + +static const struct of_device_id __iommu_of_table_sentinel + __used __section(__iommu_of_table_end); + +/** + * of_get_dma_window - Parse *dma-window property and returns 0 if found. + * + * @dn: device node + * @prefix: prefix for property name if any + * @index: index to start to parse + * @busno: Returns busno if supported. Otherwise pass NULL + * @addr: Returns address that DMA starts + * @size: Returns the range that DMA can handle + * + * This supports different formats flexibly. "prefix" can be + * configured if any. "busno" and "index" are optionally + * specified. Set 0(or NULL) if not used. + */ +int of_get_dma_window(struct device_node *dn, const char *prefix, int index, + unsigned long *busno, dma_addr_t *addr, size_t *size) +{ + const __be32 *dma_window, *end; + int bytes, cur_index = 0; + char propname[NAME_MAX], addrname[NAME_MAX], sizename[NAME_MAX]; + + if (!dn || !addr || !size) + return -EINVAL; + + if (!prefix) + prefix = ""; + + snprintf(propname, sizeof(propname), "%sdma-window", prefix); + snprintf(addrname, sizeof(addrname), "%s#dma-address-cells", prefix); + snprintf(sizename, sizeof(sizename), "%s#dma-size-cells", prefix); + + dma_window = of_get_property(dn, propname, &bytes); + if (!dma_window) + return -ENODEV; + end = dma_window + bytes / sizeof(*dma_window); + + while (dma_window < end) { + u32 cells; + const void *prop; + + /* busno is one cell if supported */ + if (busno) + *busno = be32_to_cpup(dma_window++); + + prop = of_get_property(dn, addrname, NULL); + if (!prop) + prop = of_get_property(dn, "#address-cells", NULL); + + cells = prop ? be32_to_cpup(prop) : of_n_addr_cells(dn); + if (!cells) + return -EINVAL; + *addr = of_read_number(dma_window, cells); + dma_window += cells; + + prop = of_get_property(dn, sizename, NULL); + cells = prop ? be32_to_cpup(prop) : of_n_size_cells(dn); + if (!cells) + return -EINVAL; + *size = of_read_number(dma_window, cells); + dma_window += cells; + + if (cur_index++ == index) + break; + } + return 0; +} +EXPORT_SYMBOL_GPL(of_get_dma_window); + +struct of_iommu_node { + struct list_head list; + struct device_node *np; + struct iommu_ops *ops; +}; +static LIST_HEAD(of_iommu_list); +static DEFINE_SPINLOCK(of_iommu_lock); + +void of_iommu_set_ops(struct device_node *np, struct iommu_ops *ops) +{ + struct of_iommu_node *iommu = kzalloc(sizeof(*iommu), GFP_KERNEL); + + if (WARN_ON(!iommu)) + return; + + INIT_LIST_HEAD(&iommu->list); + iommu->np = np; + iommu->ops = ops; + spin_lock(&of_iommu_lock); + list_add_tail(&iommu->list, &of_iommu_list); + spin_unlock(&of_iommu_lock); +} + +struct iommu_ops *of_iommu_get_ops(struct device_node *np) +{ + struct of_iommu_node *node; + struct iommu_ops *ops = NULL; + + spin_lock(&of_iommu_lock); + list_for_each_entry(node, &of_iommu_list, list) + if (node->np == np) { + ops = node->ops; + break; + } + spin_unlock(&of_iommu_lock); + return ops; +} + +struct iommu_ops *of_iommu_configure(struct device *dev, + struct device_node *master_np) +{ + struct of_phandle_args iommu_spec; + struct device_node *np; + struct iommu_ops *ops = NULL; + int idx = 0; + + if (dev_is_pci(dev)) { + dev_err(dev, "IOMMU is currently not supported for PCI\n"); + return NULL; + } + + /* + * We don't currently walk up the tree looking for a parent IOMMU. + * See the `Notes:' section of + * Documentation/devicetree/bindings/iommu/iommu.txt + */ + while (!of_parse_phandle_with_args(master_np, "iommus", + "#iommu-cells", idx, + &iommu_spec)) { + np = iommu_spec.np; + ops = of_iommu_get_ops(np); + + if (!ops || !ops->of_xlate || ops->of_xlate(dev, &iommu_spec)) + goto err_put_node; + + of_node_put(np); + idx++; + } + + return ops; + +err_put_node: + of_node_put(np); + return NULL; +} + +void __init of_iommu_init(void) +{ + struct device_node *np; + const struct of_device_id *match, *matches = &__iommu_of_table; + + for_each_matching_node_and_match(np, matches, &match) { + const of_iommu_init_fn init_fn = match->data; + + if (init_fn(np)) + pr_err("Failed to initialise IOMMU %s\n", + of_node_full_name(np)); + } +} -- cgit v1.2.3