diff options
| author | Simon Glass <sjg@chromium.org> | 2014-07-23 06:55:03 -0600 |
|---|---|---|
| committer | Simon Glass <sjg@chromium.org> | 2014-07-23 14:07:24 +0100 |
| commit | 00606d7e39da4a8ecfbbc19d5af252bdfdd1fcc9 (patch) | |
| tree | 53f8d51b84e75120a3b673946e515ffcbe250ceb /include/dm/device-internal.h | |
| parent | 6133683320ece056e49051e52a180adb21992b40 (diff) | |
dm: Allow drivers to be marked 'before relocation'
Driver model currently only operates after relocation is complete. In this
state U-Boot typically has a small amount of memory available. In adding
support for driver model prior to relocation we must try to use as little
memory as possible.
In addition, on some machines the memory has not be inited and/or the CPU
is not running at full speed or the data cache is off. These can reduce
execution performance, so the less initialisation that is done before
relocation the better.
An immediately-obvious improvement is to only initialise drivers which are
actually going to be used before relocation. On many boards the only such
driver is a serial UART, so this provides a very large potential benefit.
Allow drivers to mark themselves as 'pre-reloc' which means that they will
be initialised prior to relocation. This can be done either with a driver
flag or with a 'dm,pre-reloc' device tree property.
To support this, the various dm scanning function now take a 'pre_reloc_only'
parameter which indicates that only drivers marked pre-reloc should be
bound.
Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'include/dm/device-internal.h')
| -rw-r--r-- | include/dm/device-internal.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/dm/device-internal.h b/include/dm/device-internal.h index 26e5cf530e..7005d03d08 100644 --- a/include/dm/device-internal.h +++ b/include/dm/device-internal.h @@ -45,12 +45,14 @@ int device_bind(struct udevice *parent, struct driver *drv, * tree. * * @parent: Pointer to device's parent + * @pre_reloc_only: If true, bind the driver only if its DM_INIT_F flag is set. + * If false bind the driver always. * @info: Name and platdata for this device * @devp: Returns a pointer to the bound device * @return 0 if OK, -ve on error */ -int device_bind_by_name(struct udevice *parent, const struct driver_info *info, - struct udevice **devp); +int device_bind_by_name(struct udevice *parent, bool pre_reloc_only, + const struct driver_info *info, struct udevice **devp); /** * device_probe() - Probe a device, activating it |