| Message ID | 1424378462-22105-1-git-send-email-nikhil.nd@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Feb 20, 2015 at 02:11:02AM +0530, Nikhil Devshatwar wrote: > This patch changes the dtc grammar to allow following syntax > > i2cexp: &i2c2 { > ... > }; > > Current device tree compiler allows to define multiple labels when defining > the device node the first time. Typically device nodes are defined in > DTSI files. Now these nodes can be overwritten for updating some of the > properties. Typically, device nodes are overridden in DTS files. > > When working with adapter boards, most of the time adapter board can fit to > multiple base boards. But depending on which base board it is connected to, > the devices on the adapter board would be children of different devices. > > e.g. On dra7-evm.dts, i2c2 is exported for expansion connector whereas > on dra72-evm.dts, i2c5 is exported for expansion connector. > This causes a problem when writing a generic device tree file for > the adapter board. Because, you cannot know whether all the devices on > adapter board are present on i2c or i2c5. > > The problem can be solved by adding a common label (e.g. i2cexp) in both > of the DTS files when overriding the device nodes for i2c2 or i2c5. > This way, generic adapter board file would override the i2cexp. And > depending on which base board you use the adapter board, all the devices > are automatically added for correct device nodes. > > Signed-off-by: Nikhil Devshatwar <nikhil.nd@ti.com> Applied, thanks. I did tweak the testcase to use dtbs_unordered_equal instead of going through the set of tree1 tests. The fact that you can only apply a single label by this method is a bit of a wart, but it's something we can fix later. I had a look at it and (as I suspect you already discovered) it's surprisingly complicated to do so.
> -----Original Message----- > From: David Gibson [mailto:david@gibson.dropbear.id.au] > Sent: Monday, February 23, 2015 7:18 AM > To: Devshatwar, Nikhil > Cc: jdl@jdl.com; devicetree-compiler@vger.kernel.org; linux- > omap@vger.kernel.org > Subject: Re: [PATCH v2] dtc: parser: Add label while overriding nodes > > On Fri, Feb 20, 2015 at 02:11:02AM +0530, Nikhil Devshatwar wrote: > > This patch changes the dtc grammar to allow following syntax > > > > i2cexp: &i2c2 { > > ... > > }; > > > > Current device tree compiler allows to define multiple labels when > > defining the device node the first time. Typically device nodes are > > defined in DTSI files. Now these nodes can be overwritten for > updating > > some of the properties. Typically, device nodes are overridden in DTS > files. > > > > When working with adapter boards, most of the time adapter board can > > fit to multiple base boards. But depending on which base board it is > > connected to, the devices on the adapter board would be children of > different devices. > > > > e.g. On dra7-evm.dts, i2c2 is exported for expansion connector > whereas > > on dra72-evm.dts, i2c5 is exported for expansion connector. > > This causes a problem when writing a generic device tree file for the > > adapter board. Because, you cannot know whether all the devices on > > adapter board are present on i2c or i2c5. > > > > The problem can be solved by adding a common label (e.g. i2cexp) in > > both of the DTS files when overriding the device nodes for i2c2 or > i2c5. > > This way, generic adapter board file would override the i2cexp. And > > depending on which base board you use the adapter board, all the > > devices are automatically added for correct device nodes. > > > > Signed-off-by: Nikhil Devshatwar <nikhil.nd@ti.com> > > Applied, thanks. > OK, thanks, that's first upstream contribution! > I did tweak the testcase to use dtbs_unordered_equal instead of going > through the set of tree1 tests. > > The fact that you can only apply a single label by this method is a bit > of a wart, but it's something we can fix later. I had a look at it and > (as I suspect you already discovered) it's surprisingly complicated to > do so. Yes, but for now even one label can suffice the needs of the problem > > -- > David Gibson | I'll have my music baroque, and my code > david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ > _other_ > | _way_ _around_! > http://www.ozlabs.org/~dgibson -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/dtc-parser.y b/dtc-parser.y index ea57e0a..5a897e3 100644 --- a/dtc-parser.y +++ b/dtc-parser.y @@ -140,6 +140,18 @@ devicetree: { $$ = merge_nodes($1, $3); } + + | devicetree DT_LABEL DT_REF nodedef + { + struct node *target = get_node_by_ref($1, $3); + + add_label(&target->labels, $2); + if (target) + merge_nodes(target, $4); + else + ERROR(&@3, "Label or path %s not found", $3); + $$ = $1; + } | devicetree DT_REF nodedef { struct node *target = get_node_by_ref($1, $2); diff --git a/tests/run_tests.sh b/tests/run_tests.sh index c5856d9..7c5f6ac 100755 --- a/tests/run_tests.sh +++ b/tests/run_tests.sh @@ -399,6 +399,8 @@ dtc_tests () { tree1_tests dtc_tree1_merge.test.dtb test_tree1.dtb run_dtc_test -I dts -O dtb -o dtc_tree1_merge_labelled.test.dtb test_tree1_merge_labelled.dts tree1_tests dtc_tree1_merge_labelled.test.dtb test_tree1.dtb + run_dtc_test -I dts -O dtb -o dtc_tree1_label_noderef.test.dtb test_tree1_label_noderef.dts + tree1_tests dtc_tree1_label_noderef.test.dtb test_tree1.dtb run_dtc_test -I dts -O dtb -o multilabel_merge.test.dtb multilabel_merge.dts run_test references multilabel.test.dtb run_test dtbs_equal_ordered multilabel.test.dtb multilabel_merge.test.dtb diff --git a/tests/test_tree1_label_noderef.dts b/tests/test_tree1_label_noderef.dts new file mode 100644 index 0000000..b2b194c --- /dev/null +++ b/tests/test_tree1_label_noderef.dts @@ -0,0 +1,55 @@ +/dts-v1/; + +/memreserve/ 0xdeadbeef00000000 0x100000; +/memreserve/ 123456789 010000; + +/ { + compatible = "test_tree1"; + prop-int = <0xdeadbeef>; + prop-int64 = /bits/ 64 <0xdeadbeef01abcdef>; + prop-str = "hello world"; + #address-cells = <1>; + #size-cells = <0>; + + subnode@1 { + compatible = "subnode1"; + reg = <1>; + prop-int = [deadbeef]; + + subsubnode { + compatible = "subsubnode1", "subsubnode"; + prop-int = <0xdeadbeef>; + }; + + ss1 { + }; + }; + + subnode@2 { + reg = <2>; + linux,phandle = <0x2000>; + prop-int = <123456789>; + #address-cells = <1>; + #size-cells = <0>; + + ssn0: subsubnode@0 { + phandle = <0x2001>; + prop-int = <0xbad>; + }; + + ss2 { + }; + }; +}; + +/* Add label to a noderef */ +ssn1: &ssn0 { + reg = <0>; + prop-int = <123456789>; +}; + +/* Use the new label for merging */ +&ssn1 { + prop-int = <0726746425>; + compatible = "subsubnode2", "subsubnode"; +};
This patch changes the dtc grammar to allow following syntax i2cexp: &i2c2 { ... }; Current device tree compiler allows to define multiple labels when defining the device node the first time. Typically device nodes are defined in DTSI files. Now these nodes can be overwritten for updating some of the properties. Typically, device nodes are overridden in DTS files. When working with adapter boards, most of the time adapter board can fit to multiple base boards. But depending on which base board it is connected to, the devices on the adapter board would be children of different devices. e.g. On dra7-evm.dts, i2c2 is exported for expansion connector whereas on dra72-evm.dts, i2c5 is exported for expansion connector. This causes a problem when writing a generic device tree file for the adapter board. Because, you cannot know whether all the devices on adapter board are present on i2c or i2c5. The problem can be solved by adding a common label (e.g. i2cexp) in both of the DTS files when overriding the device nodes for i2c2 or i2c5. This way, generic adapter board file would override the i2cexp. And depending on which base board you use the adapter board, all the devices are automatically added for correct device nodes. Signed-off-by: Nikhil Devshatwar <nikhil.nd@ti.com> --- dtc-parser.y | 12 ++++++++ tests/run_tests.sh | 2 ++ tests/test_tree1_label_noderef.dts | 55 ++++++++++++++++++++++++++++++++++++ 3 files changed, 69 insertions(+) create mode 100644 tests/test_tree1_label_noderef.dts