lkml.org 
[lkml]   [2014]   [Sep]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH] ARM: /proc/cpuinfo: Use DT machine name when possible
    Date
    On Friday 05 September 2014 15:45:42 Mark Rutland wrote:
    > On Fri, Sep 05, 2014 at 12:38:40PM +0100, Pali Rohár wrote:
    > > On Wednesday 18 June 2014 18:54:24 Pali Rohár wrote:
    > > > Machine name from board description is some generic name
    > > > on DT kernel. DT provides machine name property which is
    > > > specific for board, so use it instead generic one when
    > > > possible.
    > > >
    > > > Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
    > > > ---
    > > >
    > > > arch/arm/kernel/setup.c | 7 +++++--
    > > > 1 file changed, 5 insertions(+), 2 deletions(-)
    > > >
    > > > diff --git a/arch/arm/kernel/setup.c
    > > > b/arch/arm/kernel/setup.c index 8a16ee5..fbc7b4f 100644
    > > > --- a/arch/arm/kernel/setup.c
    > > > +++ b/arch/arm/kernel/setup.c
    > > > @@ -875,10 +875,13 @@ void __init setup_arch(char
    > > > **cmdline_p)
    > > >
    > > > setup_processor();
    > > > mdesc = setup_machine_fdt(__atags_pointer);
    > > >
    > > > - if (!mdesc)
    > > > + if (mdesc)
    > > > + machine_name = of_flat_dt_get_machine_name();
    > > > + else
    > > >
    > > > mdesc = setup_machine_tags(__atags_pointer,
    > > >
    > > > __machine_arch_type); machine_desc = mdesc;
    > > > - machine_name = mdesc->name;
    > > > + if (!machine_name)
    > > > + machine_name = mdesc->name;
    > > >
    > > > if (mdesc->reboot_mode != REBOOT_HARD)
    > > >
    > > > reboot_mode = mdesc->reboot_mode;
    > >
    > > So, do you really want to break userspace which reading file
    > > /proc/cpuinfo (after migration from boardcode --> DT)?
    >
    > You have no guarantee model name in the DT == the name in a
    > board file anyhow, and trying to force that is wrong. So
    > further to Russell's reply, I must NAK this from a DT
    > perspective.
    >
    > Realistically your userspace is already broken if relying on
    > such things. You built something that only ever worked for a
    > particular arbitrary string. So it was already broken for
    > every other board, and there was never any guarantee that new
    > boards where your userspace could have worked would share the
    > same name.
    >
    > You're trying to fix the wrong side of the equation.
    >
    > Mark.

    So what is your suggestion for identifing board (name/type) which
    will work with any kernel (and will not be broken again by kernel
    later)?

    --
    Pali Rohár
    pali.rohar@gmail.com
    [unhandled content-type:application/pgp-signature]
    \
     
     \ /
      Last update: 2014-09-05 16:21    [W:4.115 / U:0.124 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site