diff options
| -rw-r--r-- | drivers/acpi/resource.c | 35 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 79 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 2 | ||||
| -rw-r--r-- | include/linux/acpi.h | 8 |
4 files changed, 124 insertions, 0 deletions
diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c index 93f1b5ce89b9..d85e010ee2cc 100644 --- a/drivers/acpi/resource.c +++ b/drivers/acpi/resource.c @@ -635,6 +635,41 @@ int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list, } EXPORT_SYMBOL_GPL(acpi_dev_get_resources); +static int is_memory(struct acpi_resource *ares, void *not_used) +{ + struct resource_win win; + struct resource *res = &win.res; + + memset(&win, 0, sizeof(win)); + + return !(acpi_dev_resource_memory(ares, res) + || acpi_dev_resource_address_space(ares, &win) + || acpi_dev_resource_ext_address_space(ares, &win)); +} + +/** + * acpi_dev_get_dma_resources - Get current DMA resources of a device. + * @adev: ACPI device node to get the resources for. + * @list: Head of the resultant list of resources (must be empty). + * + * Evaluate the _DMA method for the given device node and process its + * output. + * + * The resultant struct resource objects are put on the list pointed to + * by @list, that must be empty initially, as members of struct + * resource_entry objects. Callers of this routine should use + * %acpi_dev_free_resource_list() to free that list. + * + * The number of resources in the output list is returned on success, + * an error code reflecting the error condition is returned otherwise. + */ +int acpi_dev_get_dma_resources(struct acpi_device *adev, struct list_head *list) +{ + return __acpi_dev_get_resources(adev, list, is_memory, NULL, + METHOD_NAME__DMA); +} +EXPORT_SYMBOL_GPL(acpi_dev_get_dma_resources); + /** * acpi_dev_filter_resource_type - Filter ACPI resource according to resource * types diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 33897298f03e..94500d99f2d6 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1360,6 +1360,85 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) } /** + * acpi_dma_get_range() - Get device DMA parameters. + * + * @dev: device to configure + * @dma_addr: pointer device DMA address result + * @offset: pointer to the DMA offset result + * @size: pointer to DMA range size result + * + * Evaluate DMA regions and return respectively DMA region start, offset + * and size in dma_addr, offset and size on parsing success; it does not + * update the passed in values on failure. + * + * Return 0 on success, < 0 on failure. + */ +int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset, + u64 *size) +{ + struct acpi_device *adev; + LIST_HEAD(list); + struct resource_entry *rentry; + int ret; + struct device *dma_dev = dev; + u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0; + + /* + * Walk the device tree chasing an ACPI companion with a _DMA + * object while we go. Stop if we find a device with an ACPI + * companion containing a _DMA method. + */ + do { + adev = ACPI_COMPANION(dma_dev); + if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA)) + break; + + dma_dev = dma_dev->parent; + } while (dma_dev); + + if (!dma_dev) + return -ENODEV; + + if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) { + acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n"); + return -EINVAL; + } + + ret = acpi_dev_get_dma_resources(adev, &list); + if (ret > 0) { + list_for_each_entry(rentry, &list, node) { + if (dma_offset && rentry->offset != dma_offset) { + ret = -EINVAL; + dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n"); + goto out; + } + dma_offset = rentry->offset; + + /* Take lower and upper limits */ + if (rentry->res->start < dma_start) + dma_start = rentry->res->start; + if (rentry->res->end > dma_end) + dma_end = rentry->res->end; + } + + if (dma_start >= dma_end) { + ret = -EINVAL; + dev_dbg(dma_dev, "Invalid DMA regions configuration\n"); + goto out; + } + + *dma_addr = dma_start - dma_offset; + len = dma_end - dma_start; + *size = max(len, len + 1); + *offset = dma_offset; + } + out: + acpi_dev_free_resource_list(&list); + + return ret >= 0 ? 0 : ret; +} + +/** * acpi_dma_configure - Set-up DMA configuration for the device. * @dev: The pointer to the device * @attr: device dma attributes diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 68bc6be447fd..07eb963b5026 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -578,6 +578,8 @@ struct acpi_pci_root { bool acpi_dma_supported(struct acpi_device *adev); enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev); +int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset, + u64 *size); int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); void acpi_dma_deconfigure(struct device *dev); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index c749eef1daa1..a5eaff9f2c6d 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -427,6 +427,8 @@ void acpi_dev_free_resource_list(struct list_head *list); int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list, int (*preproc)(struct acpi_resource *, void *), void *preproc_data); +int acpi_dev_get_dma_resources(struct acpi_device *adev, + struct list_head *list); int acpi_dev_filter_resource_type(struct acpi_resource *ares, unsigned long types); @@ -774,6 +776,12 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) return DEV_DMA_NOT_SUPPORTED; } +static inline int acpi_dma_get_range(struct device *dev, u64 *dma_addr, + u64 *offset, u64 *size) +{ + return -ENODEV; +} + static inline int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) { |