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| author |   Maxime Ripard <maxime.ripard@bootlin.com> | 2019-04-01 10:56:44 +0200 |
|---|---|---|
| committer |   Rob Herring <robh@kernel.org> | 2019-04-10 16:33:47 -0500 |
| commit | f83a6e5dea6cf71d39c6b70a07cbe99b4ef48fe1 (patch) | |
| tree | 773797721d7faffa0054dc42421db2667a2d761e /drivers/of | |
| parent | of: address: Retrieve a parent through a callback in __of_translate_address (diff) | |
| download | linux-dev-f83a6e5dea6cf71d39c6b70a07cbe99b4ef48fe1.tar.xz linux-dev-f83a6e5dea6cf71d39c6b70a07cbe99b4ef48fe1.zip | |
of: address: Add support for the parent DMA bus
Some SoCs have devices that are using a separate bus from the main bus to
perform DMA.
These buses might have some restrictions and/or different mapping than from
the CPU side, so we'd need to express those using the usual dma-ranges, but
using a different DT node than the node's parent.
Now that the generic interconnect bindings are available, we can model an
interconnect with the reserved name "dma-mem" for those use-cases.
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Diffstat (limited to 'drivers/of')
| -rw-r--r-- | drivers/of/address.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c index 5359a80c4e8c..978427a9d5e6 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -677,12 +677,30 @@ u64 of_translate_address(struct device_node *dev, const __be32 *in_addr) } EXPORT_SYMBOL(of_translate_address); +static struct device_node *__of_get_dma_parent(const struct device_node *np) +{ + struct of_phandle_args args; + int ret, index; + + index = of_property_match_string(np, "interconnect-names", "dma-mem"); + if (index < 0) + return of_get_parent(np); + + ret = of_parse_phandle_with_args(np, "interconnects", + "#interconnect-cells", + index, &args); + if (ret < 0) + return of_get_parent(np); + + return of_node_get(args.np); +} + u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr) { struct device_node *host; u64 ret; - ret = __of_translate_address(dev, of_get_parent, + ret = __of_translate_address(dev, __of_get_dma_parent, in_addr, "dma-ranges", &host); if (host) { @@ -912,9 +930,15 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz return -EINVAL; while (1) { + struct device_node *parent; + naddr = of_n_addr_cells(node); nsize = of_n_size_cells(node); - node = of_get_next_parent(node); + + parent = __of_get_dma_parent(node); + of_node_put(node); + + node = parent; if (!node) break; |