Linux supports platform_get_resource_byname() to look up a resource
by name.

We want a similar helper.  It is useful when a device node has named
register regions.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

This function is usefull to get phandle number contained
in a property list.
For example,  this allows to allocate the right amount
of memory to keep clock's reference contained into the
"clocks" property.

To implement it, either of_count_phandle_with_args() or
fdtdec_parse_phandle_with_args() are used respectively
for live tree and flat tree.
By passing index = -1, these 2 functions returns the
number of phandle contained into the property list.

Add also the dev_count_phandle_with_args() based on
ofnode_count_phandle_with_args()
Signed-off-by: NPatrice Chotard <patrice.chotard@st.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

At present this function only supports 32-bit (single-cell) values. Update
it to support two-cell values also.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Tested-by: NMarcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-on: Beaver, Jetson-TK1
Tested-by: NStephen Warren <swarren@nvidia.com>

We sometimes need to read a resource from an arbitrary node. In any case
for consistency we should not put the live-tree switching code in
a dev_read_...() function. Update this to suit.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Tested-by: NMarcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-on: Beaver, Jetson-TK1
Tested-by: NStephen Warren <swarren@nvidia.com>

DTB is encoded in big endian.  When we retrieve property values,
we need to use fdt32_to_cpu (aka be32_to_cpu) for endian conversion.
This is a bit error-prone, but sparse is useful to detect endian
mismatch.

We need to use (fdt32_t *) instead of (u32 *) for a pointer of a
property value.  Otherwise sparse warns "cast to restricted __be32".
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

Reuse ofnode_get_property() to simplify the implementation.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NSimon Glass <sjg@chromium.org>

This function returns the pointer to the value of a node property.
The current name ofnode_read_prop() is confusing.  Follow the naming
of_get_property() from Linux.

The return type (const u32 *) is wrong.  DT property values can be
strings as well as integers.  This is why of_get_property/fdt_getprop
returns an opaque pointer.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NSimon Glass <sjg@chromium.org>

The code inside the if-block is the same as of_get_property().
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NSimon Glass <sjg@chromium.org>

This will clarify the code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NSimon Glass <sjg@chromium.org>

The of_n_addr_cells() and of_n_size_cells() functions are useful for
getting the size of addresses in a node, but in a few places U-Boot needs
to obtain the actual property value for a node without walking up the
stack. Add functions for this and just the existing code to use it.

Add a comment to the existing ofnode functions which do not do the right
thing with a flat tree.

This fixes a problem reading PCI addresses.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Tested-by: NMarcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-on: Beaver, Jetson-TK1

This provides a way to find the number of strings in a string list. Add it
and also fix up the comment for ofnode_read_string_index().
Signed-off-by: NSimon Glass <sjg@chromium.org>
Tested-by: NMarcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-on: Beaver, Jetson-TK1

Add some definitions and helpers for livetree in the main of.h header
file. These include:

- reading multi-cell integers
- default number of address/size cells
- functions for comparing names
Signed-off-by: NSimon Glass <sjg@chromium.org>

These two functions have an of_ prefix which conflicts with naming used
in of_addr. Rename them:

   fdt_read_number
   fdt_support_bus_default_count_cells
Signed-off-by: NSimon Glass <sjg@chromium.org>

Add functions to add addresses in the device tree using ofnode references.
Signed-off-by: NSimon Glass <sjg@chromium.org>

Since U-Boot supports both a live tree and a flat tree, we need an easy
way to access the tree without worrying about which is currently active.
To support this, U-Boot has the concept of an ofnode, which can refer
either to a live tree node or a flat tree node.

For the live tree, the reference contains a pointer to the node (struct
device_node *) or NULL if the node is invalid. For the flat tree, the
reference contains the node offset or -1 if the node is invalid.

Add a basic set of operations using ofnodes. These are implemented by
using either libfdt functions (in the case of a flat DT reference) or
the live-tree of_...() functions.

Note that it is not possible to have both live and flat references active
at the same time. As soon as the live tree is available, everything in
U-Boot should switch to using that. This avoids confusion and allows us to
assume that the type of a reference is simply based on whether we have a
live tree yet, or not.
Signed-off-by: NSimon Glass <sjg@chromium.org>