On 26 March 2016 at 09:12, Jan Viktorin [off-list ref] wrote:

Hello,

while extending the DPDK by a kind of platform devices (for the 16.07), an
access to the FDT might be necessary (or at least very helpful). This patch
series for 16.07 introduces an approach to solve this topic.

The API is designed from scratch and there is only the Linux backend for it.
The Linux backend can read and traverse the /proc/device-tree structure. The
API, however, stays as independent as possible. It is possible to:

* open the FDT in a platform independent way (rte_fdt_open/close)
* define a path in the FDT in an abstract way (rte_fdt_path)
* read strings, 32 and 64 bit values, a binary content (rte_fdt_path_readX)
* walk the FDT structure from a selected point (rte_fdt_path_walk)

I've included unit tests of the API and of the Linux implemention. Some basic
API tests are introduced in the patch 3. Then a simplified device-tree file
structure is added together with more tests testing the Linux backend (4,5).
I've left those 3 patches separated for now but I think they can be aggregated
into a single patch later.

Here, I've encounter an issue. The testing FDT files (app/test/linux-fdt) need
to be copied (or linked) to the working directory of the _test_ executable. I
have no idea, how to integrate such logic into the build system.

Why not store FDT files in the code, for example, as a group of binary arrays?
When test is executed, it firstly creates the files in the working
directory from those arrays.

Jianbo