Commit ec331c6f authored by Jordan Yates's avatar Jordan Yates Committed by Anas Nashif
Browse files

device: simplify structure of handles array 



Force the inclusion of a `DEVICE_HANDLE_SEP` at the end of the
devicetree dependency section of the array. This lets us simplify the
implementation of `device_required_handles_get`, as there is only one
symbol the section ends with.

This does not use any extra ROM as the array is padded out to the
original size with `DEVICE_HANDLE_ENDS` anyway.

Also adds a description of the array format where the array is
instantiated.

Signed-off-by: default avatarJordan Yates <jordan.yates@data61.csiro.au>
parent b5c4140a

include/device.h

+17 −2
Original line number Diff line number Diff line
@@ -478,8 +478,7 @@ device_required_handles_get(const struct device *dev, 
	if (rv != NULL) {

		size_t i = 0;



		while ((rv[i] != DEVICE_HANDLE_ENDS)

		       && (rv[i] != DEVICE_HANDLE_SEP)) {

		while (rv[i] != DEVICE_HANDLE_SEP) {

			++i;

		}

		*count = i;
@@ -674,6 +673,22 @@ static inline bool device_is_ready(const struct device *dev) 
 * in a distinct pass1 section (which will be replaced by

 * postprocessing).

 *

 * Before processing in gen_handles.py, the array format is:

 * {

 *     DEVICE_ORDINAL (or DEVICE_HANDLE_NULL if not a devicetree node),

 *     List of devicetree dependency ordinals (if any),

 *     DEVICE_HANDLE_SEP,

 *     List of injected dependency ordinals (if any),

 * }

 *

 * After processing in gen_handles.py, the format is updated to:

 * {

 *     List of existing devicetree dependency handles (if any),

 *     DEVICE_HANDLE_SEP,

 *     List of injected dependency ordinals (if any),

 *     DEVICE_HANDLE_NULL padding to original length (at least one)

 * }

 *

 * It is also (experimentally) necessary to provide explicit alignment

 * on each object. Otherwise x86-64 builds will introduce padding

 * between objects in the same input section in individual object

scripts/gen_handles.py

+2 −1
Original line number Diff line number Diff line
@@ -294,10 +294,11 @@ def main(): 
                        dep_paths.append(dn.path)

                    else:

                        dep_paths.append('(%s)' % dn.path)

            # Force separator to signal start of injected dependencies

            hdls.append(DEVICE_HANDLE_SEP)

            if len(hs.ext_deps) > 0:

                # TODO: map these to something smaller?

                ext_paths.extend(map(str, hs.ext_deps))

                hdls.append(DEVICE_HANDLE_SEP)

                hdls.extend(hs.ext_deps)



            # When CONFIG_USERSPACE is enabled the pre-built elf is

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