[PATCH v5 07/11] drivers: dma-coherent: add initialization from device tree
From: m.szyprowski@samsung.com (Marek Szyprowski)
Date: 2014-02-21 12:26:21
Also in:
linux-devicetree, lkml
Subsystem:
driver core, kobjects, debugfs and sysfs, the rest · Maintainers:
Greg Kroah-Hartman, "Rafael J. Wysocki", Danilo Krummrich, Linus Torvalds
Add support for handling 'shared-dma-pool' reserved-memory device tree nodes. Based on previous code provided by Josh Cartwright [off-list ref] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- drivers/base/dma-coherent.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+)
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index bc256b641027..2343ba5d6d43 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c@@ -218,3 +218,44 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma, return 0; } EXPORT_SYMBOL(dma_mmap_from_coherent); + +/* + * Support for reserved memory regions defined in device tree + */ +#ifdef CONFIG_OF_RESERVED_MEM +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> + +static void rmem_dma_device_init(struct reserved_mem *rmem, + struct device *dev, struct of_phandle_args *args) +{ + dma_declare_coherent_memory(dev, rmem->base, rmem->base, + rmem->size, DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE); +} + +static void rmem_dma_device_release(struct reserved_mem *rmem, + struct device *dev) +{ + dma_release_declared_memory(dev); +} + +static const struct reserved_mem_ops rmem_dma_ops = { + .device_init = rmem_dma_device_init, + .device_release = rmem_dma_device_release, +}; + +static int __init rmem_dma_setup(struct reserved_mem *rmem, + unsigned long node, + const char *uname) +{ + if (of_get_flat_dt_prop(node, "reusable", NULL)) + return -EINVAL; + + rmem->ops = &rmem_dma_ops; + pr_info("Reserved memory: created DMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + return 0; +} +RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup); +#endif
--
1.7.9.5