[PATCH 1/2] dm: core: Add functions to read 8/16-bit integers

Simon Glass sjg at chromium.org
Wed Jul 13 17:28:08 CEST 2022


Hi Stefan,

On Tue, 12 Jul 2022 at 12:31, Stefan Herbrechtsmeier
<stefan.herbrechtsmeier-oss at weidmueller.com> wrote:
>
> Hi Simon,
>
> Am 12.07.2022 um 12:58 schrieb Simon Glass:
> > Hi Stefan,
> >
> > On Tue, 14 Jun 2022 at 07:22, Stefan Herbrechtsmeier
> > <stefan.herbrechtsmeier-oss at weidmueller.com> wrote:
> >>
> >> From: Stefan Herbrechtsmeier <stefan.herbrechtsmeier at weidmueller.com>
> >>
> >> Add functions to read 8/16-bit integers like the existing functions for
> >> 32/64-bit to simplify read of 8/16-bit integers from device tree
> >> properties.
> >>
> >> Signed-off-by: Stefan Herbrechtsmeier <stefan.herbrechtsmeier at weidmueller.com>
> >> ---
> >>
> >>   arch/sandbox/dts/test.dts |  2 ++
> >>   drivers/core/of_access.c  | 38 +++++++++++++++++++++++
> >>   drivers/core/ofnode.c     | 62 +++++++++++++++++++++++++++++++++++++
> >>   drivers/core/read.c       | 21 +++++++++++++
> >>   include/dm/of_access.h    | 32 +++++++++++++++++++
> >>   include/dm/ofnode.h       | 40 ++++++++++++++++++++++++
> >>   include/dm/read.h         | 65 +++++++++++++++++++++++++++++++++++++++
> >>   test/dm/test-fdt.c        | 19 ++++++++++++
> >>   8 files changed, 279 insertions(+)
> >
> > This looks good but is very expensive in terms of code size. Can you
> > update your u8 and u16 functions to reuse the existing u32 function
> > and just convert the value?
>
> The u32 function requires a 32 bit value inside the device tree because
> it checks the size and maybe swap the bytes.
>
> The u8 and u16 function requires only a 8 and 16 bit value inside the
> device tree.

Yes that's true. What is the use case for these functions?

Reviewed-by: Simon Glass <sjg at chromium.org>

Regards,
Simon


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