On Mon, 7 Jan 2019 at 12:23, Simon Goldschmidt <simon.k.r.goldschm...@gmail.com> wrote: > > Improve some things in the documentation of OF_PLATDATA that I found > while porting socfgpa_gen5 to it. > > Signed-off-by: Simon Goldschmidt <simon.k.r.goldschm...@gmail.com> > --- > > doc/driver-model/of-plat.txt | 18 ++++++++++++------ > dts/Kconfig | 6 ++---- > 2 files changed, 14 insertions(+), 10 deletions(-)
Reviewed-by: Simon Glass <s...@chromium.org> > > diff --git a/doc/driver-model/of-plat.txt b/doc/driver-model/of-plat.txt > index 732bc34f06..ecb5f1724b 100644 > --- a/doc/driver-model/of-plat.txt > +++ b/doc/driver-model/of-plat.txt > @@ -69,12 +69,12 @@ How it works > ------------ > > The feature is enabled by CONFIG SPL_OF_PLATDATA. This is only available > -in SPL and should be tested with: > +in SPL/TPL and should be tested with: > > #if CONFIG_IS_ENABLED(SPL_OF_PLATDATA) Actually that seems wrong. Shouldn't it omit the SPL_ part? > > A new tool called 'dtoc' converts a device tree file either into a set of > -struct declarations, one for each compatible node, or a set of > +struct declarations, one for each compatible node, and a set of > U_BOOT_DEVICE() declarations along with the actual platform data for each > device. As an example, consider this MMC node: > > @@ -156,6 +156,12 @@ This avoids the code overhead of converting the device > tree data to > platform data in the driver. The ofdata_to_platdata() method should > therefore do nothing in such a driver. > > +Note that for the platform data to be matched with a driver, the 'name' > +property of the U_BOOT_DEVICE() declaration has to match a driver declared > +via U_BOOT_DRIVER(). This effectively means that a U_BOOT_DRIVER() with a > +'name' identical to the devicetree 'compatible' string is needed, so a > +dedicated driver is required for each 'compatible' string. Not identical - e.g. hyphens change to underscores. > + > Where a node has multiple compatible strings, a #define is used to make them > equivalent, e.g.: > > @@ -165,8 +171,8 @@ equivalent, e.g.: > Converting of-platdata to a useful form > --------------------------------------- > > -Of course it would be possible use the of-platdata directly in your driver > -whenever configuration information is required. However this meands that the > +Of course it would be possible to use the of-platdata directly in your driver > +whenever configuration information is required. However this means that the > driver will not be able to support device tree, since the of-platdata > structure is not available when device tree is used. It would make no sense > to use this structure if device tree were available, since the structure has > @@ -282,8 +288,8 @@ prevents them being used inadvertently. All usage must be > bracketed with > The dt-platdata.c file contains the device declarations and is is built in > spl/dt-platdata.c. > > -Some phandles (thsoe that are recognised as such) are converted into > -points to platform data. This pointer can potentially be used to access the > +Some phandles (those that are recognised as such) are converted into > +pointer to platform data. This pointer can potentially be used to access the a pointer to platform data > referenced device (by searching for the pointer value). This feature is not > yet implemented, however. > > diff --git a/dts/Kconfig b/dts/Kconfig > index 8917f42444..3e85914d11 100644 > --- a/dts/Kconfig > +++ b/dts/Kconfig > @@ -265,8 +265,7 @@ config SPL_OF_PLATDATA > > This option works by generating C structure declarations for each > compatible string, then adding platform data and U_BOOT_DEVICE > - declarations for each node. See README.platdata for more > - information. > + declarations for each node. See of-plat.txt for more information. > > config TPL_OF_PLATDATA > bool "Generate platform data for use in TPL" > @@ -287,8 +286,7 @@ config TPL_OF_PLATDATA > > This option works by generating C structure declarations for each > compatible string, then adding platform data and U_BOOT_DEVICE > - declarations for each node. See README.platdata for more > - information. > + declarations for each node. See of-plat.txt for more information. > > endmenu > > -- > 2.17.1 > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
