Commit Graph

11 Commits

Author SHA1 Message Date
Thierry Reding
7dfb61ba96 libfdt: Use fdt_find_max_phandle()
Use the fdt_find_max_phandle() function instead of the deprecated
fdt_get_max_phandle() function.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Message-Id: <20190326153302.17109-2-thierry.reding@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-29 13:31:16 +11:00
David Gibson
04b5b4062c libfdt: Clean up header checking functions
Many of the libfdt entry points call some sort of sanity check function
before doing anything else.  These need to do slightly different things for
the various classes of functions.

The read-only version is shared with the exported fdt_check_header(), which
limits us a bit in how we can improve it.  For that reason split the two
functions apart (though the exported one just calls the ro one for now).

We also rename the functions for more consistency - they're all named
fdt_XX_probe_() where the XX indicates which class of functions they're
for.  "probe" is a better "term" than the previous check, since they really
only do minimal validation.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2018-06-07 11:45:44 +10:00
Maxime Ripard
65893da4ae libfdt: overlay: Add missing license
The overlay support has been introduced, but the copyright and license
header was missing. Make sure that this is no longer the case.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-10 19:56:14 +11:00
Pantelis Antoniou
1bb00655d3 fdt: Allow stacked overlays phandle references
This patch enables an overlay to refer to a previous overlay's
labels by performing a merge of symbol information at application
time.

In a nutshell it allows an overlay to refer to a symbol that a previous
overlay has defined. It requires both the base and all the overlays
to be compiled with the -@ command line switch so that symbol
information is included.

base.dts
--------

	/dts-v1/;
	/ {
		foo: foonode {
			foo-property;
		};
	};

	$ dtc -@ -I dts -O dtb -o base.dtb base.dts

bar.dts
-------

	/dts-v1/;
	/plugin/;
	/ {
		fragment@1 {
			target = <&foo>;
			__overlay__ {
				overlay-1-property;
				bar: barnode {
					bar-property;
				};
			};
		};
	};

	$ dtc -@ -I dts -O dtb -o bar.dtb bar.dts

baz.dts
-------

	/dts-v1/;
	/plugin/;
	/ {
		fragment@1 {
			target = <&bar>;
			__overlay__ {
				overlay-2-property;
				baz: baznode {
					baz-property;
				};
			};
		};
	};

	$ dtc -@ -I dts -O dtb -o baz.dtb baz.dts

Applying the overlays:

	$ fdtoverlay -i base.dtb -o target.dtb bar.dtb baz.dtb

Dumping:

	$ fdtdump target.dtb
	/ {
            foonode {
                overlay-1-property;
                foo-property;
                linux,phandle = <0x00000001>;
                phandle = <0x00000001>;
                barnode {
                    overlay-2-property;
                    phandle = <0x00000002>;
                    linux,phandle = <0x00000002>;
                    bar-property;
                    baznode {
                        phandle = <0x00000003>;
                        linux,phandle = <0x00000003>;
                        baz-property;
                    };
                };
            };
            __symbols__ {
                baz = "/foonode/barnode/baznode";
                bar = "/foonode/barnode";
                foo = "/foonode";
            };
	};

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-08-09 17:18:47 +10:00
Nicolas Iooss
921cc17fec libfdt: overlay: Check the value of the right variable
overlay_update_local_node_references() saves the result of
fdt_subnode_offset() into variable tree_child but checks for variable
ret afterwards. As this does not make sense, check tree_child instead of
ret.

This bug has been found by compiling with clang. The compiler reported
the following warning:

    libfdt/fdt_overlay.c:275:7: error: variable 'ret' may be
    uninitialized when used here
          [-Werror,-Wconditional-uninitialized]
                    if (ret == -FDT_ERR_NOTFOUND)
                        ^~~
    libfdt/fdt_overlay.c:210:9: note: initialize the variable 'ret' to
    silence this
          warning
            int ret;
                   ^
                    = 0

Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-03-06 14:19:26 +11:00
David Gibson
bad5b28049 Fix assorted sparse warnings
This fixes a great many sparse warnings on the fdt and libfdt sources.
These are mostly due to incorrect mixing of endian annotated and native
integer types.

This includes fixing a couple of quasi-bugs where we had endian conversions
the wrong way around (this will have the right effect in practice, but is
certainly conceptually incorrect).

This doesn't make the whole tree sparse clean: there are many warnings in
bison and lex generated code, and there are a handful of other remaining
warnings that are (for now) more trouble than they're worth to fix (and
are not genuine bugs).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-03-06 12:08:53 +11:00
David Gibson
7d8ef6e1db tests: Correct fdt handling of overlays without fixups and base trees without symbols
The fdt_overlay_apply() function purports to support the edge cases where
an overlay has no fixups to be applied, or a base tree which has no
symbols (the latter can only work if the former is also true).  However it
gets it wrong in a couple of small ways:

  * In the no fixups case, it doesn't fail immediately, but will attempt
    fdt_for_each_property_offset() giving -FDT_ERR_NOTFOUND as the node
    offset, which will fail.  Instead it should succeed immediately, since
    there's nothing to do.
  * In the case of no symbols, it again doesn't fail immediately.  However
    if there is an actual fixup it will fail with an unexpected error,
    because -FDT_ERR_NOTFOUND is passed to fdt_getprop() when attempting to
    look up the symbols.  We should instead return -FDT_ERR_NOTFOUND
    directly.

Both of these errors lead to the code returning misleading error codes in
failing cases.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-12-09 16:13:29 +11:00
Maxime Ripard
7a72d89d3f libfdt: overlay: Fix symbols and fixups nodes condition
Some base device tree might not have any __symbols__ nodes, since they
might not have any phandle at all.

Similarly, if an overlay doesn't use any base device tree phandles, its
__fixups__ node will be empty.

In such cases, we don't want to stop the phandle parsing, but rather just
ignore the error reported about the missing node.

If it's actually an issue for the overlay we're trying to apply on a given
base device tree, it will be caught later on, but we cannot make the
assumption that early in the application process.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-07 12:28:58 +11:00
Maxime Ripard
cabbaa972c libfdt: overlay: Report a bad overlay for mismatching local fixups
The __local_fixups__ node as a structure that mimics the structure of the
main overlay part.

This means that if we have a child node somewhere in the local fixups
sub-tree and if that node is not present in the main tree, the overlay is
poorly formatted, and we should report it as such.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-07 12:28:58 +11:00
David Gibson
7b7a6be9ba libfdt: Don't use 'index' as a local variable name
Using 'index' as a local variable name shadows the standard library index()
function.  This causes warnings on at least some compiler versions.  The
recently added overlay code has a number of instances of this.

This patch replaces 'index' with 'poffset', since 'index' is being used to
mean "offset within a property value" in these cases.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-06 20:45:14 +11:00
Maxime Ripard
0cdd06c513 libfdt: Add overlay application function
The device tree overlays are a good way to deal with user-modifyable
boards or boards with some kind of an expansion mechanism where we can
easily plug new board in (like the BBB, the Raspberry Pi or the CHIP).

Add a new function to merge overlays with a base device tree.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-06 19:22:41 +11:00