diff options
| author | Tom Rini <trini@konsulko.com> | 2018-10-10 13:35:17 -0400 |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2018-10-10 13:35:17 -0400 |
| commit | 3d5ced9e22d32112a20f9dc0f5fb1f22ef088079 (patch) | |
| tree | 2c1e1f34c4dad05dfd08bd3687e6aee634c58500 /doc | |
| parent | 98068b3be51a77d8b931a2f5097b5c22c57bcea5 (diff) | |
| parent | 41b781ddf1869f5349e05ace888979f3673fe8c6 (diff) | |
| download | u-boot-3d5ced9e22d32112a20f9dc0f5fb1f22ef088079.tar.gz | |
Merge tag 'dm-9oct18' of git://git.denx.de/u-boot-dm
Test improvements to tidy up output and drop duplicate tests
Sandbox SPL/TPL support
Various dm-related improvements
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/README.fdt-control | 16 | ||||
| -rw-r--r-- | doc/driver-model/README.txt | 7 |
2 files changed, 20 insertions, 3 deletions
diff --git a/doc/README.fdt-control b/doc/README.fdt-control index 634a10616f..d6ab7bf570 100644 --- a/doc/README.fdt-control +++ b/doc/README.fdt-control @@ -56,7 +56,11 @@ In case you are wondering, OF stands for Open Firmware. Tools ----- -To use this feature you will need to get the device tree compiler here: +To use this feature you will need to get the device tree compiler. This is +provided by U-Boot automatically. If you have a system version of dtc +(typically in the 'device-tree-compiler' package), it is currently not used. + +If you want to build your own dtc, it is kept here: git://git.kernel.org/pub/scm/utils/dtc/dtc.git @@ -170,6 +174,16 @@ After board configuration is done, fdt supported u-boot can be build in two ways $ make DEVICE_TREE=<dts-file-name> +Relocation, SPL and TPL +----------------------- + +U-Boot can be divided into three phases: TPL, SPL and U-Boot proper. + +The full device tree is available to U-Boot proper, but normally only a subset +(or none at all) is available to TPL and SPL. See 'Pre-Relocation Support' and +'SPL Support' in doc/driver-model/README.txt for more details. + + Limitations ----------- diff --git a/doc/driver-model/README.txt b/doc/driver-model/README.txt index e949ff63ba..36541630a2 100644 --- a/doc/driver-model/README.txt +++ b/doc/driver-model/README.txt @@ -832,11 +832,14 @@ Pre-Relocation Support For pre-relocation we simply call the driver model init function. Only drivers marked with DM_FLAG_PRE_RELOC or the device tree 'u-boot,dm-pre-reloc' flag are initialised prior to relocation. This helps -to reduce the driver model overhead. +to reduce the driver model overhead. This flag applies to SPL and TPL as +well, if device tree is enabled there. It is possible to limit this to specific relocation steps, by using the more specialized 'u-boot,dm-spl' and 'u-boot,dm-tpl' flags -in the devicetree. +in the device tree node. For U-Boot proper you can use 'u-boot,dm-pre-proper' +which means that it will be processed (and a driver bound) in U-Boot proper +prior to relocation, but will not be available in SPL or TPL. Then post relocation we throw that away and re-init driver model again. For drivers which require some sort of continuity between pre- and |