Commit e251c213 authored by Thierry Reding's avatar Thierry Reding Committed by Joerg Roedel
Browse files

of: Introduce of_translate_dma_region() 



This function is similar to of_translate_dma_address() but also reads a
length in addition to an address from a device tree property.

Reviewed-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20230120174251.4004100-2-thierry.reding@gmail.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent bb649412

drivers/of/address.c

+41 −0
Original line number Diff line number Diff line
@@ -626,6 +626,47 @@ u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr) 
}

EXPORT_SYMBOL(of_translate_dma_address);



/**

 * of_translate_dma_region - Translate device tree address and size tuple

 * @dev: device tree node for which to translate

 * @prop: pointer into array of cells

 * @start: return value for the start of the DMA range

 * @length: return value for the length of the DMA range

 *

 * Returns a pointer to the cell immediately following the translated DMA region.

 */

const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop,

				      phys_addr_t *start, size_t *length)

{

	struct device_node *parent;

	u64 address, size;

	int na, ns;



	parent = __of_get_dma_parent(dev);

	if (!parent)

		return NULL;



	na = of_bus_n_addr_cells(parent);

	ns = of_bus_n_size_cells(parent);



	of_node_put(parent);



	address = of_translate_dma_address(dev, prop);

	if (address == OF_BAD_ADDR)

		return NULL;



	size = of_read_number(prop + na, ns);



	if (start)

		*start = address;



	if (length)

		*length = size;



	return prop + na + ns;

}

EXPORT_SYMBOL(of_translate_dma_region);



const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no,

			       u64 *size, unsigned int *flags)

{

include/linux/of_address.h

+2 −0
Original line number Diff line number Diff line
@@ -38,6 +38,8 @@ struct of_pci_range { 
/* Translate a DMA address from device space to CPU space */

extern u64 of_translate_dma_address(struct device_node *dev,

				    const __be32 *in_addr);

extern const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *addr,

					     phys_addr_t *start, size_t *length);



#ifdef CONFIG_OF_ADDRESS

extern u64 of_translate_address(struct device_node *np, const __be32 *addr);